libnetwork: remove consul-related code and tests

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
This commit is contained in:
Sebastiaan van Stijn 2021-12-16 14:22:19 +01:00
parent 25594c33b9
commit 147173b099
No known key found for this signature in database
GPG Key ID: 76698F39D527CE8C
24 changed files with 2 additions and 3988 deletions

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@ -114,7 +114,7 @@ type ScopeClientCfg struct {
const (
// LocalScope indicates to store the KV object in local datastore such as boltdb
LocalScope = "local"
// GlobalScope indicates to store the KV object in global datastore such as consul/etcd
// GlobalScope indicates to store the KV object in global datastore such as etcd
GlobalScope = "global"
// SwarmScope is not indicating a datastore location. It is defined here
// along with the other two scopes just for consistency.

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@ -1,153 +0,0 @@
# Overlay Driver
### Design
TODO
### Multi-Host Overlay Driver Quick Start
This example is to provision two Docker Hosts with the **experimental** Libnetwork overlay network driver.
### Pre-Requisites
- Kernel >= 3.16
- Experimental Docker client
### Install Docker Experimental
Follow Docker experimental installation instructions at: [https://github.com/docker/docker/tree/master/experimental](https://github.com/docker/docker/tree/master/experimental)
To ensure you are running the experimental Docker branch, check the version and look for the experimental tag:
```
$ docker -v
Docker version 1.8.0-dev, build f39b9a0, experimental
```
### Install and Bootstrap K/V Store
Multi-host networking uses a pluggable Key-Value store backend to distribute states using `libkv`.
`libkv` supports multiple pluggable backends such as `consul`, `etcd` (more to come).
In this example we will use `consul`
Install:
```
$ curl -OL https://dl.bintray.com/mitchellh/consul/0.5.2_linux_amd64.zip
$ unzip 0.5.2_linux_amd64.zip
$ mv consul /usr/local/bin/
```
**host-1** Start Consul as a server in bootstrap mode:
```
$ consul agent -server -bootstrap -data-dir /tmp/consul -bind=<host-1-ip-address>
```
**host-2** Start the Consul agent:
```
$ consul agent -data-dir /tmp/consul -bind=<host-2-ip-address>
$ consul join <host-1-ip-address>
```
### Start the Docker Daemon with the Network Driver Daemon Flags
**host-1** Docker daemon:
```
$ docker -d --kv-store=consul:localhost:8500 --label=com.docker.network.driver.overlay.bind_interface=eth0
```
**host-2** Start the Docker Daemon with the neighbor ID configuration:
```
$ docker -d --kv-store=consul:localhost:8500 --label=com.docker.network.driver.overlay.bind_interface=eth0 --label=com.docker.network.driver.overlay.neighbor_ip=<host-1-ip-address>
```
### QuickStart Containers Attached to a Network
**host-1** Start a container that publishes a service svc1 in the network dev that is managed by overlay driver.
```
$ docker run -i -t --publish-service=svc1.dev.overlay debian
root@21578ff721a9:/# ip add show eth0
34: eth0: <BROADCAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default
link/ether 02:42:ec:41:35:bf brd ff:ff:ff:ff:ff:ff
inet 172.21.0.16/16 scope global eth0
valid_lft forever preferred_lft forever
inet6 fe80::42:ecff:fe41:35bf/64 scope link
valid_lft forever preferred_lft forever
```
**host-2** Start a container that publishes a service svc2 in the network dev that is managed by overlay driver.
```
$ docker run -i -t --publish-service=svc2.dev.overlay debian
root@d217828eb876:/# ping svc1
PING svc1 (172.21.0.16): 56 data bytes
64 bytes from 172.21.0.16: icmp_seq=0 ttl=64 time=0.706 ms
64 bytes from 172.21.0.16: icmp_seq=1 ttl=64 time=0.687 ms
64 bytes from 172.21.0.16: icmp_seq=2 ttl=64 time=0.841 ms
```
### Detailed Setup
You can also setup networks and services and then attach a running container to them.
**host-1**:
```
docker network create -d overlay prod
docker network ls
docker network info prod
docker service publish db1.prod
cid=$(docker run -itd -p 8000:8000 ubuntu)
docker service attach $cid db1.prod
```
**host-2**:
```
docker network ls
docker network info prod
docker service publish db2.prod
cid=$(docker run -itd -p 8000:8000 ubuntu)
docker service attach $cid db2.prod
```
Once a container is started, a container on `host-1` and `host-2` both containers should be able to ping one another via IP, service name, \<service name>.\<network name>
View information about the networks and services using `ls` and `info` subcommands like so:
```
$ docker service ls
SERVICE ID NAME NETWORK CONTAINER
0771deb5f84b db2 prod 0e54a527f22c
aea23b224acf db1 prod 4b0a309ca311
$ docker network info prod
Network Id: 5ac68be2518959b48ad102e9ec3d8f42fb2ec72056aa9592eb5abd0252203012
Name: prod
Type: overlay
$ docker service info db1.prod
Service Id: aea23b224acfd2da9b893870e0d632499188a1a4b3881515ba042928a9d3f465
Name: db1
Network: prod
```
To detach and unpublish a service:
```
$ docker service detach $cid <service>.<network>
$ docker service unpublish <service>.<network>
# Example:
$ docker service detach $cid db2.prod
$ docker service unpublish db2.prod
```
To reiterate, this is experimental, and will be under active development.

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@ -6,13 +6,11 @@ import (
"github.com/docker/docker/libnetwork/datastore"
"github.com/docker/libkv/store/boltdb"
"github.com/docker/libkv/store/consul"
"github.com/docker/libkv/store/etcd"
"github.com/sirupsen/logrus"
)
func registerKVStores() {
consul.Register()
etcd.Register()
boltdb.Register()
}

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@ -40,23 +40,6 @@ function net_disconnect() {
dnet_cmd $(inst_id2port ${1}) service unpublish ${2}.${3}
}
function start_consul() {
stop_consul
docker run -d \
--name=pr_consul \
-p 8500:8500 \
-p 8300-8302:8300-8302/tcp \
-p 8300-8302:8300-8302/udp \
-h consul \
progrium/consul -server -bootstrap
sleep 2
}
function stop_consul() {
echo "consul started"
docker rm -f pr_consul || true
}
hrun() {
local e E T oldIFS
[[ ! "$-" =~ e ]] || e=1
@ -151,8 +134,6 @@ function start_dnet() {
neighbors=""
if [ "$store" = "etcd" ]; then
read discovery provider address < <(parse_discovery_str etcd://${bridge_ip}:42000/custom_prefix)
elif [ "$store" = "consul" ]; then
read discovery provider address < <(parse_discovery_str consul://${bridge_ip}:8500/custom_prefix)
else
if [ "$nip" != "" ]; then
neighbors=${nip}

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@ -1,8 +0,0 @@
# -*- mode: sh -*-
#!/usr/bin/env bats
load helpers
@test "Test overlay network hostmode with consul" {
test_overlay_hostmode consul
}

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@ -1,56 +0,0 @@
# -*- mode: sh -*-
#!/usr/bin/env bats
load helpers
@test "Test overlay network with consul" {
test_overlay consul
}
@test "Test overlay network singlehost with consul" {
test_overlay_singlehost consul
}
@test "Test overlay network with dnet restart" {
test_overlay consul skip_rm
docker restart dnet-1-consul
wait_for_dnet $(inst_id2port 1) dnet-1-consul
docker restart dnet-2-consul
wait_for_dnet $(inst_id2port 2) dnet-2-consul
docker restart dnet-3-consul
wait_for_dnet $(inst_id2port 3) dnet-3-consul
test_overlay consul skip_add
}
@test "Test overlay network internal network with consul" {
test_overlay consul internal
}
@test "Test overlay network with dnet ungraceful shutdown" {
dnet_cmd $(inst_id2port 1) network create -d overlay multihost
start=1
end=3
for i in `seq ${start} ${end}`;
do
dnet_cmd $(inst_id2port $i) container create container_${i}
net_connect ${i} container_${i} multihost
done
hrun runc $(dnet_container_name 1 consul) $(get_sbox_id 1 container_1) "ifconfig eth0"
container_1_ip=$(echo ${output} | grep 'inet addr:' | cut -d: -f2 | awk '{ print $1}')
# ungracefully kill dnet-1-consul container
docker rm -f dnet-1-consul
# forcefully unpublish the service from dnet2 when dnet1 is dead.
dnet_cmd $(inst_id2port 2) service unpublish -f container_1.multihost
dnet_cmd $(inst_id2port 2) container create container_1
net_connect 2 container_1 multihost
hrun runc $(dnet_container_name 2 consul) $(get_sbox_id 2 container_1) "ifconfig eth0"
container_1_new_ip=$(echo ${output} | grep 'inet addr:' | cut -d: -f2 | awk '{ print $1}')
if [ "$container_1_ip" != "$container_1_new_ip" ]; then
exit 1
fi
}

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@ -52,43 +52,6 @@ function run_overlay_local_tests() {
unset cmap[dnet-3-local]
}
function run_overlay_consul_tests() {
## Test overlay network with consul
## Setup
start_dnet 1 consul 1>> ${INTEGRATION_ROOT}/test.log 2>&1
cmap[dnet - 1 - consul]=dnet-1-consul
start_dnet 2 consul 1>> ${INTEGRATION_ROOT}/test.log 2>&1
cmap[dnet - 2 - consul]=dnet-2-consul
start_dnet 3 consul 1>> ${INTEGRATION_ROOT}/test.log 2>&1
cmap[dnet - 3 - consul]=dnet-3-consul
## Run the test cases
./integration-tmp/bin/bats ./test/integration/dnet/overlay-consul.bats
## Teardown
stop_dnet 1 consul 1>> ${INTEGRATION_ROOT}/test.log 2>&1
unset cmap[dnet-1-consul]
stop_dnet 2 consul 1>> ${INTEGRATION_ROOT}/test.log 2>&1
unset cmap[dnet-2-consul]
stop_dnet 3 consul 1>> ${INTEGRATION_ROOT}/test.log 2>&1
unset cmap[dnet-3-consul]
}
function run_overlay_consul_host_tests() {
export _OVERLAY_HOST_MODE="true"
## Setup
start_dnet 1 consul 1>> ${INTEGRATION_ROOT}/test.log 2>&1
cmap[dnet - 1 - consul]=dnet-1-consul
## Run the test cases
./integration-tmp/bin/bats ./test/integration/dnet/overlay-consul-host.bats
## Teardown
stop_dnet 1 consul 1>> ${INTEGRATION_ROOT}/test.log 2>&1
unset cmap[dnet-1-consul]
unset _OVERLAY_HOST_MODE
}
function run_overlay_etcd_tests() {
## Test overlay network with etcd
start_dnet 1 etcd 1>> ${INTEGRATION_ROOT}/test.log 2>&1
@ -113,29 +76,6 @@ function run_dnet_tests() {
./integration-tmp/bin/bats ./test/integration/dnet/dnet.bats
}
function run_multi_consul_tests() {
# Test multi node configuration with a global scope test driver backed by consul
## Setup
start_dnet 1 multi_consul consul 1>> ${INTEGRATION_ROOT}/test.log 2>&1
cmap[dnet - 1 - multi_consul]=dnet-1-multi_consul
start_dnet 2 multi_consul consul 1>> ${INTEGRATION_ROOT}/test.log 2>&1
cmap[dnet - 2 - multi_consul]=dnet-2-multi_consul
start_dnet 3 multi_consul consul 1>> ${INTEGRATION_ROOT}/test.log 2>&1
cmap[dnet - 3 - multi_consul]=dnet-3-multi_consul
## Run the test cases
./integration-tmp/bin/bats ./test/integration/dnet/multi.bats
## Teardown
stop_dnet 1 multi_consul 1>> ${INTEGRATION_ROOT}/test.log 2>&1
unset cmap[dnet-1-multi_consul]
stop_dnet 2 multi_consul 1>> ${INTEGRATION_ROOT}/test.log 2>&1
unset cmap[dnet-2-multi_consul]
stop_dnet 3 multi_consul 1>> ${INTEGRATION_ROOT}/test.log 2>&1
unset cmap[dnet-3-multi_consul]
}
function run_multi_etcd_tests() {
# Test multi node configuration with a global scope test driver backed by etcd
@ -178,17 +118,11 @@ fi
# Suite setup
if [ -z "$SUITES" ]; then
suites="dnet multi_consul multi_etcd bridge overlay_consul overlay_consul_host overlay_etcd"
suites="dnet multi_etcd bridge overlay_etcd"
else
suites="$SUITES"
fi
if [[ ("$suites" =~ .*consul.*) || ("$suites" =~ .*bridge.*) ]]; then
echo "Starting consul ..."
start_consul 1>> ${INTEGRATION_ROOT}/test.log 2>&1
cmap[pr_consul]=pr_consul
fi
if [[ "$suites" =~ .*etcd.* ]]; then
echo "Starting etcd ..."
start_etcd 1>> ${INTEGRATION_ROOT}/test.log 2>&1

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@ -63,7 +63,6 @@ github.com/google/btree 479b5e81b0a93ec038d201b0b33d
github.com/deckarep/golang-set ef32fa3046d9f249d399f98ebaf9be944430fd1d
github.com/coreos/etcd 973882f697a8db3d59815bf132c6c506434334bd # v3.3.27
github.com/coreos/go-semver 8ab6407b697782a06568d4b7f1db25550ec2e4c6 # v0.2.0
github.com/hashicorp/consul 9a9cc9341bb487651a0399e3fc5e1e8a42e62dd9 # v0.5.2
github.com/miekg/dns 6c0c4e6581f8e173cc562c8b3363ab984e4ae071 # v1.1.27
github.com/ishidawataru/sctp f2269e66cdee387bd321445d5d300893449805be
go.etcd.io/bbolt 232d8fc87f50244f9c808f4745759e08a304c029 # v1.3.5

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@ -1,558 +0,0 @@
package consul
import (
"crypto/tls"
"errors"
"net/http"
"strings"
"sync"
"time"
"github.com/docker/libkv"
"github.com/docker/libkv/store"
api "github.com/hashicorp/consul/api"
)
const (
// DefaultWatchWaitTime is how long we block for at a
// time to check if the watched key has changed. This
// affects the minimum time it takes to cancel a watch.
DefaultWatchWaitTime = 15 * time.Second
// RenewSessionRetryMax is the number of time we should try
// to renew the session before giving up and throwing an error
RenewSessionRetryMax = 5
// MaxSessionDestroyAttempts is the maximum times we will try
// to explicitely destroy the session attached to a lock after
// the connectivity to the store has been lost
MaxSessionDestroyAttempts = 5
// defaultLockTTL is the default ttl for the consul lock
defaultLockTTL = 20 * time.Second
)
var (
// ErrMultipleEndpointsUnsupported is thrown when there are
// multiple endpoints specified for Consul
ErrMultipleEndpointsUnsupported = errors.New("consul does not support multiple endpoints")
// ErrSessionRenew is thrown when the session can't be
// renewed because the Consul version does not support sessions
ErrSessionRenew = errors.New("cannot set or renew session for ttl, unable to operate on sessions")
)
// Consul is the receiver type for the
// Store interface
type Consul struct {
sync.Mutex
config *api.Config
client *api.Client
}
type consulLock struct {
lock *api.Lock
renewCh chan struct{}
}
// Register registers consul to libkv
func Register() {
libkv.AddStore(store.CONSUL, New)
}
// New creates a new Consul client given a list
// of endpoints and optional tls config
func New(endpoints []string, options *store.Config) (store.Store, error) {
if len(endpoints) > 1 {
return nil, ErrMultipleEndpointsUnsupported
}
s := &Consul{}
// Create Consul client
config := api.DefaultConfig()
s.config = config
config.HttpClient = http.DefaultClient
config.Address = endpoints[0]
config.Scheme = "http"
// Set options
if options != nil {
if options.TLS != nil {
s.setTLS(options.TLS)
}
if options.ConnectionTimeout != 0 {
s.setTimeout(options.ConnectionTimeout)
}
}
// Creates a new client
client, err := api.NewClient(config)
if err != nil {
return nil, err
}
s.client = client
return s, nil
}
// SetTLS sets Consul TLS options
func (s *Consul) setTLS(tls *tls.Config) {
s.config.HttpClient.Transport = &http.Transport{
TLSClientConfig: tls,
}
s.config.Scheme = "https"
}
// SetTimeout sets the timeout for connecting to Consul
func (s *Consul) setTimeout(time time.Duration) {
s.config.WaitTime = time
}
// Normalize the key for usage in Consul
func (s *Consul) normalize(key string) string {
key = store.Normalize(key)
return strings.TrimPrefix(key, "/")
}
func (s *Consul) renewSession(pair *api.KVPair, ttl time.Duration) error {
// Check if there is any previous session with an active TTL
session, err := s.getActiveSession(pair.Key)
if err != nil {
return err
}
if session == "" {
entry := &api.SessionEntry{
Behavior: api.SessionBehaviorDelete, // Delete the key when the session expires
TTL: (ttl / 2).String(), // Consul multiplies the TTL by 2x
LockDelay: 1 * time.Millisecond, // Virtually disable lock delay
}
// Create the key session
session, _, err = s.client.Session().Create(entry, nil)
if err != nil {
return err
}
lockOpts := &api.LockOptions{
Key: pair.Key,
Session: session,
}
// Lock and ignore if lock is held
// It's just a placeholder for the
// ephemeral behavior
lock, _ := s.client.LockOpts(lockOpts)
if lock != nil {
lock.Lock(nil)
}
}
_, _, err = s.client.Session().Renew(session, nil)
return err
}
// getActiveSession checks if the key already has
// a session attached
func (s *Consul) getActiveSession(key string) (string, error) {
pair, _, err := s.client.KV().Get(key, nil)
if err != nil {
return "", err
}
if pair != nil && pair.Session != "" {
return pair.Session, nil
}
return "", nil
}
// Get the value at "key", returns the last modified index
// to use in conjunction to CAS calls
func (s *Consul) Get(key string) (*store.KVPair, error) {
options := &api.QueryOptions{
AllowStale: false,
RequireConsistent: true,
}
pair, meta, err := s.client.KV().Get(s.normalize(key), options)
if err != nil {
return nil, err
}
// If pair is nil then the key does not exist
if pair == nil {
return nil, store.ErrKeyNotFound
}
return &store.KVPair{Key: pair.Key, Value: pair.Value, LastIndex: meta.LastIndex}, nil
}
// Put a value at "key"
func (s *Consul) Put(key string, value []byte, opts *store.WriteOptions) error {
key = s.normalize(key)
p := &api.KVPair{
Key: key,
Value: value,
Flags: api.LockFlagValue,
}
if opts != nil && opts.TTL > 0 {
// Create or renew a session holding a TTL. Operations on sessions
// are not deterministic: creating or renewing a session can fail
for retry := 1; retry <= RenewSessionRetryMax; retry++ {
err := s.renewSession(p, opts.TTL)
if err == nil {
break
}
if retry == RenewSessionRetryMax {
return ErrSessionRenew
}
}
}
_, err := s.client.KV().Put(p, nil)
return err
}
// Delete a value at "key"
func (s *Consul) Delete(key string) error {
if _, err := s.Get(key); err != nil {
return err
}
_, err := s.client.KV().Delete(s.normalize(key), nil)
return err
}
// Exists checks that the key exists inside the store
func (s *Consul) Exists(key string) (bool, error) {
_, err := s.Get(key)
if err != nil {
if err == store.ErrKeyNotFound {
return false, nil
}
return false, err
}
return true, nil
}
// List child nodes of a given directory
func (s *Consul) List(directory string) ([]*store.KVPair, error) {
pairs, _, err := s.client.KV().List(s.normalize(directory), nil)
if err != nil {
return nil, err
}
if len(pairs) == 0 {
return nil, store.ErrKeyNotFound
}
kv := []*store.KVPair{}
for _, pair := range pairs {
if pair.Key == directory {
continue
}
kv = append(kv, &store.KVPair{
Key: pair.Key,
Value: pair.Value,
LastIndex: pair.ModifyIndex,
})
}
return kv, nil
}
// DeleteTree deletes a range of keys under a given directory
func (s *Consul) DeleteTree(directory string) error {
if _, err := s.List(directory); err != nil {
return err
}
_, err := s.client.KV().DeleteTree(s.normalize(directory), nil)
return err
}
// Watch for changes on a "key"
// It returns a channel that will receive changes or pass
// on errors. Upon creation, the current value will first
// be sent to the channel. Providing a non-nil stopCh can
// be used to stop watching.
func (s *Consul) Watch(key string, stopCh <-chan struct{}) (<-chan *store.KVPair, error) {
kv := s.client.KV()
watchCh := make(chan *store.KVPair)
go func() {
defer close(watchCh)
// Use a wait time in order to check if we should quit
// from time to time.
opts := &api.QueryOptions{WaitTime: DefaultWatchWaitTime}
for {
// Check if we should quit
select {
case <-stopCh:
return
default:
}
// Get the key
pair, meta, err := kv.Get(key, opts)
if err != nil {
return
}
// If LastIndex didn't change then it means `Get` returned
// because of the WaitTime and the key didn't changed.
if opts.WaitIndex == meta.LastIndex {
continue
}
opts.WaitIndex = meta.LastIndex
// Return the value to the channel
// FIXME: What happens when a key is deleted?
if pair != nil {
watchCh <- &store.KVPair{
Key: pair.Key,
Value: pair.Value,
LastIndex: pair.ModifyIndex,
}
}
}
}()
return watchCh, nil
}
// WatchTree watches for changes on a "directory"
// It returns a channel that will receive changes or pass
// on errors. Upon creating a watch, the current childs values
// will be sent to the channel .Providing a non-nil stopCh can
// be used to stop watching.
func (s *Consul) WatchTree(directory string, stopCh <-chan struct{}) (<-chan []*store.KVPair, error) {
kv := s.client.KV()
watchCh := make(chan []*store.KVPair)
go func() {
defer close(watchCh)
// Use a wait time in order to check if we should quit
// from time to time.
opts := &api.QueryOptions{WaitTime: DefaultWatchWaitTime}
for {
// Check if we should quit
select {
case <-stopCh:
return
default:
}
// Get all the childrens
pairs, meta, err := kv.List(directory, opts)
if err != nil {
return
}
// If LastIndex didn't change then it means `Get` returned
// because of the WaitTime and the child keys didn't change.
if opts.WaitIndex == meta.LastIndex {
continue
}
opts.WaitIndex = meta.LastIndex
// Return children KV pairs to the channel
kvpairs := []*store.KVPair{}
for _, pair := range pairs {
if pair.Key == directory {
continue
}
kvpairs = append(kvpairs, &store.KVPair{
Key: pair.Key,
Value: pair.Value,
LastIndex: pair.ModifyIndex,
})
}
watchCh <- kvpairs
}
}()
return watchCh, nil
}
// NewLock returns a handle to a lock struct which can
// be used to provide mutual exclusion on a key
func (s *Consul) NewLock(key string, options *store.LockOptions) (store.Locker, error) {
lockOpts := &api.LockOptions{
Key: s.normalize(key),
}
lock := &consulLock{}
ttl := defaultLockTTL
if options != nil {
// Set optional TTL on Lock
if options.TTL != 0 {
ttl = options.TTL
}
// Set optional value on Lock
if options.Value != nil {
lockOpts.Value = options.Value
}
}
entry := &api.SessionEntry{
Behavior: api.SessionBehaviorRelease, // Release the lock when the session expires
TTL: (ttl / 2).String(), // Consul multiplies the TTL by 2x
LockDelay: 1 * time.Millisecond, // Virtually disable lock delay
}
// Create the key session
session, _, err := s.client.Session().Create(entry, nil)
if err != nil {
return nil, err
}
// Place the session and renew chan on lock
lockOpts.Session = session
lock.renewCh = options.RenewLock
l, err := s.client.LockOpts(lockOpts)
if err != nil {
return nil, err
}
// Renew the session ttl lock periodically
s.renewLockSession(entry.TTL, session, options.RenewLock)
lock.lock = l
return lock, nil
}
// renewLockSession is used to renew a session Lock, it takes
// a stopRenew chan which is used to explicitely stop the session
// renew process. The renew routine never stops until a signal is
// sent to this channel. If deleting the session fails because the
// connection to the store is lost, it keeps trying to delete the
// session periodically until it can contact the store, this ensures
// that the lock is not maintained indefinitely which ensures liveness
// over safety for the lock when the store becomes unavailable.
func (s *Consul) renewLockSession(initialTTL string, id string, stopRenew chan struct{}) {
sessionDestroyAttempts := 0
ttl, err := time.ParseDuration(initialTTL)
if err != nil {
return
}
go func() {
for {
select {
case <-time.After(ttl / 2):
entry, _, err := s.client.Session().Renew(id, nil)
if err != nil {
// If an error occurs, continue until the
// session gets destroyed explicitely or
// the session ttl times out
continue
}
if entry == nil {
return
}
// Handle the server updating the TTL
ttl, _ = time.ParseDuration(entry.TTL)
case <-stopRenew:
// Attempt a session destroy
_, err := s.client.Session().Destroy(id, nil)
if err == nil {
return
}
if sessionDestroyAttempts >= MaxSessionDestroyAttempts {
return
}
// We can't destroy the session because the store
// is unavailable, wait for the session renew period
sessionDestroyAttempts++
time.Sleep(ttl / 2)
}
}
}()
}
// Lock attempts to acquire the lock and blocks while
// doing so. It returns a channel that is closed if our
// lock is lost or if an error occurs
func (l *consulLock) Lock(stopChan chan struct{}) (<-chan struct{}, error) {
return l.lock.Lock(stopChan)
}
// Unlock the "key". Calling unlock while
// not holding the lock will throw an error
func (l *consulLock) Unlock() error {
if l.renewCh != nil {
close(l.renewCh)
}
return l.lock.Unlock()
}
// AtomicPut put a value at "key" if the key has not been
// modified in the meantime, throws an error if this is the case
func (s *Consul) AtomicPut(key string, value []byte, previous *store.KVPair, options *store.WriteOptions) (bool, *store.KVPair, error) {
p := &api.KVPair{Key: s.normalize(key), Value: value, Flags: api.LockFlagValue}
if previous == nil {
// Consul interprets ModifyIndex = 0 as new key.
p.ModifyIndex = 0
} else {
p.ModifyIndex = previous.LastIndex
}
ok, _, err := s.client.KV().CAS(p, nil)
if err != nil {
return false, nil, err
}
if !ok {
if previous == nil {
return false, nil, store.ErrKeyExists
}
return false, nil, store.ErrKeyModified
}
pair, err := s.Get(key)
if err != nil {
return false, nil, err
}
return true, pair, nil
}
// AtomicDelete deletes a value at "key" if the key has not
// been modified in the meantime, throws an error if this is the case
func (s *Consul) AtomicDelete(key string, previous *store.KVPair) (bool, error) {
if previous == nil {
return false, store.ErrPreviousNotSpecified
}
p := &api.KVPair{Key: s.normalize(key), ModifyIndex: previous.LastIndex, Flags: api.LockFlagValue}
// Extra Get operation to check on the key
_, err := s.Get(key)
if err != nil && err == store.ErrKeyNotFound {
return false, err
}
if work, _, err := s.client.KV().DeleteCAS(p, nil); err != nil {
return false, err
} else if !work {
return false, store.ErrKeyModified
}
return true, nil
}
// Close closes the client connection
func (s *Consul) Close() {
return
}

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@ -1,354 +0,0 @@
Mozilla Public License, version 2.0
1. Definitions
1.1. “Contributor”
means each individual or legal entity that creates, contributes to the
creation of, or owns Covered Software.
1.2. “Contributor Version”
means the combination of the Contributions of others (if any) used by a
Contributor and that particular Contributors Contribution.
1.3. “Contribution”
means Covered Software of a particular Contributor.
1.4. “Covered Software”
means Source Code Form to which the initial Contributor has attached the
notice in Exhibit A, the Executable Form of such Source Code Form, and
Modifications of such Source Code Form, in each case including portions
thereof.
1.5. “Incompatible With Secondary Licenses”
means
a. that the initial Contributor has attached the notice described in
Exhibit B to the Covered Software; or
b. that the Covered Software was made available under the terms of version
1.1 or earlier of the License, but not also under the terms of a
Secondary License.
1.6. “Executable Form”
means any form of the work other than Source Code Form.
1.7. “Larger Work”
means a work that combines Covered Software with other material, in a separate
file or files, that is not Covered Software.
1.8. “License”
means this document.
1.9. “Licensable”
means having the right to grant, to the maximum extent possible, whether at the
time of the initial grant or subsequently, any and all of the rights conveyed by
this License.
1.10. “Modifications”
means any of the following:
a. any file in Source Code Form that results from an addition to, deletion
from, or modification of the contents of Covered Software; or
b. any new file in Source Code Form that contains any Covered Software.
1.11. “Patent Claims” of a Contributor
means any patent claim(s), including without limitation, method, process,
and apparatus claims, in any patent Licensable by such Contributor that
would be infringed, but for the grant of the License, by the making,
using, selling, offering for sale, having made, import, or transfer of
either its Contributions or its Contributor Version.
1.12. “Secondary License”
means either the GNU General Public License, Version 2.0, the GNU Lesser
General Public License, Version 2.1, the GNU Affero General Public
License, Version 3.0, or any later versions of those licenses.
1.13. “Source Code Form”
means the form of the work preferred for making modifications.
1.14. “You” (or “Your”)
means an individual or a legal entity exercising rights under this
License. For legal entities, “You” includes any entity that controls, is
controlled by, or is under common control with You. For purposes of this
definition, “control” means (a) the power, direct or indirect, to cause
the direction or management of such entity, whether by contract or
otherwise, or (b) ownership of more than fifty percent (50%) of the
outstanding shares or beneficial ownership of such entity.
2. License Grants and Conditions
2.1. Grants
Each Contributor hereby grants You a world-wide, royalty-free,
non-exclusive license:
a. under intellectual property rights (other than patent or trademark)
Licensable by such Contributor to use, reproduce, make available,
modify, display, perform, distribute, and otherwise exploit its
Contributions, either on an unmodified basis, with Modifications, or as
part of a Larger Work; and
b. under Patent Claims of such Contributor to make, use, sell, offer for
sale, have made, import, and otherwise transfer either its Contributions
or its Contributor Version.
2.2. Effective Date
The licenses granted in Section 2.1 with respect to any Contribution become
effective for each Contribution on the date the Contributor first distributes
such Contribution.
2.3. Limitations on Grant Scope
The licenses granted in this Section 2 are the only rights granted under this
License. No additional rights or licenses will be implied from the distribution
or licensing of Covered Software under this License. Notwithstanding Section
2.1(b) above, no patent license is granted by a Contributor:
a. for any code that a Contributor has removed from Covered Software; or
b. for infringements caused by: (i) Your and any other third partys
modifications of Covered Software, or (ii) the combination of its
Contributions with other software (except as part of its Contributor
Version); or
c. under Patent Claims infringed by Covered Software in the absence of its
Contributions.
This License does not grant any rights in the trademarks, service marks, or
logos of any Contributor (except as may be necessary to comply with the
notice requirements in Section 3.4).
2.4. Subsequent Licenses
No Contributor makes additional grants as a result of Your choice to
distribute the Covered Software under a subsequent version of this License
(see Section 10.2) or under the terms of a Secondary License (if permitted
under the terms of Section 3.3).
2.5. Representation
Each Contributor represents that the Contributor believes its Contributions
are its original creation(s) or it has sufficient rights to grant the
rights to its Contributions conveyed by this License.
2.6. Fair Use
This License is not intended to limit any rights You have under applicable
copyright doctrines of fair use, fair dealing, or other equivalents.
2.7. Conditions
Sections 3.1, 3.2, 3.3, and 3.4 are conditions of the licenses granted in
Section 2.1.
3. Responsibilities
3.1. Distribution of Source Form
All distribution of Covered Software in Source Code Form, including any
Modifications that You create or to which You contribute, must be under the
terms of this License. You must inform recipients that the Source Code Form
of the Covered Software is governed by the terms of this License, and how
they can obtain a copy of this License. You may not attempt to alter or
restrict the recipients rights in the Source Code Form.
3.2. Distribution of Executable Form
If You distribute Covered Software in Executable Form then:
a. such Covered Software must also be made available in Source Code Form,
as described in Section 3.1, and You must inform recipients of the
Executable Form how they can obtain a copy of such Source Code Form by
reasonable means in a timely manner, at a charge no more than the cost
of distribution to the recipient; and
b. You may distribute such Executable Form under the terms of this License,
or sublicense it under different terms, provided that the license for
the Executable Form does not attempt to limit or alter the recipients
rights in the Source Code Form under this License.
3.3. Distribution of a Larger Work
You may create and distribute a Larger Work under terms of Your choice,
provided that You also comply with the requirements of this License for the
Covered Software. If the Larger Work is a combination of Covered Software
with a work governed by one or more Secondary Licenses, and the Covered
Software is not Incompatible With Secondary Licenses, this License permits
You to additionally distribute such Covered Software under the terms of
such Secondary License(s), so that the recipient of the Larger Work may, at
their option, further distribute the Covered Software under the terms of
either this License or such Secondary License(s).
3.4. Notices
You may not remove or alter the substance of any license notices (including
copyright notices, patent notices, disclaimers of warranty, or limitations
of liability) contained within the Source Code Form of the Covered
Software, except that You may alter any license notices to the extent
required to remedy known factual inaccuracies.
3.5. Application of Additional Terms
You may choose to offer, and to charge a fee for, warranty, support,
indemnity or liability obligations to one or more recipients of Covered
Software. However, You may do so only on Your own behalf, and not on behalf
of any Contributor. You must make it absolutely clear that any such
warranty, support, indemnity, or liability obligation is offered by You
alone, and You hereby agree to indemnify every Contributor for any
liability incurred by such Contributor as a result of warranty, support,
indemnity or liability terms You offer. You may include additional
disclaimers of warranty and limitations of liability specific to any
jurisdiction.
4. Inability to Comply Due to Statute or Regulation
If it is impossible for You to comply with any of the terms of this License
with respect to some or all of the Covered Software due to statute, judicial
order, or regulation then You must: (a) comply with the terms of this License
to the maximum extent possible; and (b) describe the limitations and the code
they affect. Such description must be placed in a text file included with all
distributions of the Covered Software under this License. Except to the
extent prohibited by statute or regulation, such description must be
sufficiently detailed for a recipient of ordinary skill to be able to
understand it.
5. Termination
5.1. The rights granted under this License will terminate automatically if You
fail to comply with any of its terms. However, if You become compliant,
then the rights granted under this License from a particular Contributor
are reinstated (a) provisionally, unless and until such Contributor
explicitly and finally terminates Your grants, and (b) on an ongoing basis,
if such Contributor fails to notify You of the non-compliance by some
reasonable means prior to 60 days after You have come back into compliance.
Moreover, Your grants from a particular Contributor are reinstated on an
ongoing basis if such Contributor notifies You of the non-compliance by
some reasonable means, this is the first time You have received notice of
non-compliance with this License from such Contributor, and You become
compliant prior to 30 days after Your receipt of the notice.
5.2. If You initiate litigation against any entity by asserting a patent
infringement claim (excluding declaratory judgment actions, counter-claims,
and cross-claims) alleging that a Contributor Version directly or
indirectly infringes any patent, then the rights granted to You by any and
all Contributors for the Covered Software under Section 2.1 of this License
shall terminate.
5.3. In the event of termination under Sections 5.1 or 5.2 above, all end user
license agreements (excluding distributors and resellers) which have been
validly granted by You or Your distributors under this License prior to
termination shall survive termination.
6. Disclaimer of Warranty
Covered Software is provided under this License on an “as is” basis, without
warranty of any kind, either expressed, implied, or statutory, including,
without limitation, warranties that the Covered Software is free of defects,
merchantable, fit for a particular purpose or non-infringing. The entire
risk as to the quality and performance of the Covered Software is with You.
Should any Covered Software prove defective in any respect, You (not any
Contributor) assume the cost of any necessary servicing, repair, or
correction. This disclaimer of warranty constitutes an essential part of this
License. No use of any Covered Software is authorized under this License
except under this disclaimer.
7. Limitation of Liability
Under no circumstances and under no legal theory, whether tort (including
negligence), contract, or otherwise, shall any Contributor, or anyone who
distributes Covered Software as permitted above, be liable to You for any
direct, indirect, special, incidental, or consequential damages of any
character including, without limitation, damages for lost profits, loss of
goodwill, work stoppage, computer failure or malfunction, or any and all
other commercial damages or losses, even if such party shall have been
informed of the possibility of such damages. This limitation of liability
shall not apply to liability for death or personal injury resulting from such
partys negligence to the extent applicable law prohibits such limitation.
Some jurisdictions do not allow the exclusion or limitation of incidental or
consequential damages, so this exclusion and limitation may not apply to You.
8. Litigation
Any litigation relating to this License may be brought only in the courts of
a jurisdiction where the defendant maintains its principal place of business
and such litigation shall be governed by laws of that jurisdiction, without
reference to its conflict-of-law provisions. Nothing in this Section shall
prevent a partys ability to bring cross-claims or counter-claims.
9. Miscellaneous
This License represents the complete agreement concerning the subject matter
hereof. If any provision of this License is held to be unenforceable, such
provision shall be reformed only to the extent necessary to make it
enforceable. Any law or regulation which provides that the language of a
contract shall be construed against the drafter shall not be used to construe
this License against a Contributor.
10. Versions of the License
10.1. New Versions
Mozilla Foundation is the license steward. Except as provided in Section
10.3, no one other than the license steward has the right to modify or
publish new versions of this License. Each version will be given a
distinguishing version number.
10.2. Effect of New Versions
You may distribute the Covered Software under the terms of the version of
the License under which You originally received the Covered Software, or
under the terms of any subsequent version published by the license
steward.
10.3. Modified Versions
If you create software not governed by this License, and you want to
create a new license for such software, you may create and use a modified
version of this License if you rename the license and remove any
references to the name of the license steward (except to note that such
modified license differs from this License).
10.4. Distributing Source Code Form that is Incompatible With Secondary Licenses
If You choose to distribute Source Code Form that is Incompatible With
Secondary Licenses under the terms of this version of the License, the
notice described in Exhibit B of this License must be attached.
Exhibit A - Source Code Form License Notice
This Source Code Form is subject to the
terms of the Mozilla Public License, v.
2.0. If a copy of the MPL was not
distributed with this file, You can
obtain one at
http://mozilla.org/MPL/2.0/.
If it is not possible or desirable to put the notice in a particular file, then
You may include the notice in a location (such as a LICENSE file in a relevant
directory) where a recipient would be likely to look for such a notice.
You may add additional accurate notices of copyright ownership.
Exhibit B - “Incompatible With Secondary Licenses” Notice
This Source Code Form is “Incompatible
With Secondary Licenses”, as defined by
the Mozilla Public License, v. 2.0.

View File

@ -1,85 +0,0 @@
# Consul [![Build Status](https://travis-ci.org/hashicorp/consul.png)](https://travis-ci.org/hashicorp/consul)
* Website: http://www.consul.io
* IRC: `#consul` on Freenode
* Mailing list: [Google Groups](https://groups.google.com/group/consul-tool/)
Consul is a tool for service discovery and configuration. Consul is
distributed, highly available, and extremely scalable.
Consul provides several key features:
* **Service Discovery** - Consul makes it simple for services to register
themselves and to discover other services via a DNS or HTTP interface.
External services such as SaaS providers can be registered as well.
* **Health Checking** - Health Checking enables Consul to quickly alert
operators about any issues in a cluster. The integration with service
discovery prevents routing traffic to unhealthy hosts and enables service
level circuit breakers.
* **Key/Value Storage** - A flexible key/value store enables storing
dynamic configuration, feature flagging, coordination, leader election and
more. The simple HTTP API makes it easy to use anywhere.
* **Multi-Datacenter** - Consul is built to be datacenter aware, and can
support any number of regions without complex configuration.
Consul runs on Linux, Mac OS X, and Windows. It is recommended to run the
Consul servers only on Linux, however.
## Quick Start
An extensive quick quick start is viewable on the Consul website:
http://www.consul.io/intro/getting-started/install.html
## Documentation
Full, comprehensive documentation is viewable on the Consul website:
http://www.consul.io/docs
## Developing Consul
If you wish to work on Consul itself, you'll first need [Go](https://golang.org)
installed (version 1.4+ is _required_). Make sure you have Go properly installed,
including setting up your [GOPATH](https://golang.org/doc/code.html#GOPATH).
Next, clone this repository into `$GOPATH/src/github.com/hashicorp/consul` and
then just type `make`. In a few moments, you'll have a working `consul` executable:
```
$ go get -u ./...
$ make
...
$ bin/consul
...
```
*note: `make` will also place a copy of the binary in the first part of your $GOPATH*
You can run tests by typing `make test`.
If you make any changes to the code, run `make format` in order to automatically
format the code according to Go standards.
### Building Consul on Windows
Make sure Go 1.4+ is installed on your system and that the Go command is in your
%PATH%.
For building Consul on Windows, you also need to have MinGW installed.
[TDM-GCC](http://tdm-gcc.tdragon.net/) is a simple bundle installer which has all
the required tools for building Consul with MinGW.
Install TDM-GCC and make sure it has been added to your %PATH%.
If all goes well, you should be able to build Consul by running `make.bat` from a
command prompt.
See also [golang/winstrap](https://github.com/golang/winstrap) and
[golang/wiki/WindowsBuild](https://github.com/golang/go/wiki/WindowsBuild)
for more information of how to set up a general Go build environment on Windows
with MinGW.

View File

@ -1,39 +0,0 @@
Consul API client
=================
This package provides the `api` package which attempts to
provide programmatic access to the full Consul API.
Currently, all of the Consul APIs included in version 0.3 are supported.
Documentation
=============
The full documentation is available on [Godoc](http://godoc.org/github.com/hashicorp/consul/api)
Usage
=====
Below is an example of using the Consul client:
```go
// Get a new client, with KV endpoints
client, _ := api.NewClient(api.DefaultConfig())
kv := client.KV()
// PUT a new KV pair
p := &api.KVPair{Key: "foo", Value: []byte("test")}
_, err := kv.Put(p, nil)
if err != nil {
panic(err)
}
// Lookup the pair
pair, _, err := kv.Get("foo", nil)
if err != nil {
panic(err)
}
fmt.Printf("KV: %v", pair)
```

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@ -1,140 +0,0 @@
package api
const (
// ACLCLientType is the client type token
ACLClientType = "client"
// ACLManagementType is the management type token
ACLManagementType = "management"
)
// ACLEntry is used to represent an ACL entry
type ACLEntry struct {
CreateIndex uint64
ModifyIndex uint64
ID string
Name string
Type string
Rules string
}
// ACL can be used to query the ACL endpoints
type ACL struct {
c *Client
}
// ACL returns a handle to the ACL endpoints
func (c *Client) ACL() *ACL {
return &ACL{c}
}
// Create is used to generate a new token with the given parameters
func (a *ACL) Create(acl *ACLEntry, q *WriteOptions) (string, *WriteMeta, error) {
r := a.c.newRequest("PUT", "/v1/acl/create")
r.setWriteOptions(q)
r.obj = acl
rtt, resp, err := requireOK(a.c.doRequest(r))
if err != nil {
return "", nil, err
}
defer resp.Body.Close()
wm := &WriteMeta{RequestTime: rtt}
var out struct{ ID string }
if err := decodeBody(resp, &out); err != nil {
return "", nil, err
}
return out.ID, wm, nil
}
// Update is used to update the rules of an existing token
func (a *ACL) Update(acl *ACLEntry, q *WriteOptions) (*WriteMeta, error) {
r := a.c.newRequest("PUT", "/v1/acl/update")
r.setWriteOptions(q)
r.obj = acl
rtt, resp, err := requireOK(a.c.doRequest(r))
if err != nil {
return nil, err
}
defer resp.Body.Close()
wm := &WriteMeta{RequestTime: rtt}
return wm, nil
}
// Destroy is used to destroy a given ACL token ID
func (a *ACL) Destroy(id string, q *WriteOptions) (*WriteMeta, error) {
r := a.c.newRequest("PUT", "/v1/acl/destroy/"+id)
r.setWriteOptions(q)
rtt, resp, err := requireOK(a.c.doRequest(r))
if err != nil {
return nil, err
}
resp.Body.Close()
wm := &WriteMeta{RequestTime: rtt}
return wm, nil
}
// Clone is used to return a new token cloned from an existing one
func (a *ACL) Clone(id string, q *WriteOptions) (string, *WriteMeta, error) {
r := a.c.newRequest("PUT", "/v1/acl/clone/"+id)
r.setWriteOptions(q)
rtt, resp, err := requireOK(a.c.doRequest(r))
if err != nil {
return "", nil, err
}
defer resp.Body.Close()
wm := &WriteMeta{RequestTime: rtt}
var out struct{ ID string }
if err := decodeBody(resp, &out); err != nil {
return "", nil, err
}
return out.ID, wm, nil
}
// Info is used to query for information about an ACL token
func (a *ACL) Info(id string, q *QueryOptions) (*ACLEntry, *QueryMeta, error) {
r := a.c.newRequest("GET", "/v1/acl/info/"+id)
r.setQueryOptions(q)
rtt, resp, err := requireOK(a.c.doRequest(r))
if err != nil {
return nil, nil, err
}
defer resp.Body.Close()
qm := &QueryMeta{}
parseQueryMeta(resp, qm)
qm.RequestTime = rtt
var entries []*ACLEntry
if err := decodeBody(resp, &entries); err != nil {
return nil, nil, err
}
if len(entries) > 0 {
return entries[0], qm, nil
}
return nil, qm, nil
}
// List is used to get all the ACL tokens
func (a *ACL) List(q *QueryOptions) ([]*ACLEntry, *QueryMeta, error) {
r := a.c.newRequest("GET", "/v1/acl/list")
r.setQueryOptions(q)
rtt, resp, err := requireOK(a.c.doRequest(r))
if err != nil {
return nil, nil, err
}
defer resp.Body.Close()
qm := &QueryMeta{}
parseQueryMeta(resp, qm)
qm.RequestTime = rtt
var entries []*ACLEntry
if err := decodeBody(resp, &entries); err != nil {
return nil, nil, err
}
return entries, qm, nil
}

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@ -1,334 +0,0 @@
package api
import (
"fmt"
)
// AgentCheck represents a check known to the agent
type AgentCheck struct {
Node string
CheckID string
Name string
Status string
Notes string
Output string
ServiceID string
ServiceName string
}
// AgentService represents a service known to the agent
type AgentService struct {
ID string
Service string
Tags []string
Port int
Address string
}
// AgentMember represents a cluster member known to the agent
type AgentMember struct {
Name string
Addr string
Port uint16
Tags map[string]string
Status int
ProtocolMin uint8
ProtocolMax uint8
ProtocolCur uint8
DelegateMin uint8
DelegateMax uint8
DelegateCur uint8
}
// AgentServiceRegistration is used to register a new service
type AgentServiceRegistration struct {
ID string `json:",omitempty"`
Name string `json:",omitempty"`
Tags []string `json:",omitempty"`
Port int `json:",omitempty"`
Address string `json:",omitempty"`
Check *AgentServiceCheck
Checks AgentServiceChecks
}
// AgentCheckRegistration is used to register a new check
type AgentCheckRegistration struct {
ID string `json:",omitempty"`
Name string `json:",omitempty"`
Notes string `json:",omitempty"`
ServiceID string `json:",omitempty"`
AgentServiceCheck
}
// AgentServiceCheck is used to create an associated
// check for a service
type AgentServiceCheck struct {
Script string `json:",omitempty"`
Interval string `json:",omitempty"`
Timeout string `json:",omitempty"`
TTL string `json:",omitempty"`
HTTP string `json:",omitempty"`
Status string `json:",omitempty"`
}
type AgentServiceChecks []*AgentServiceCheck
// Agent can be used to query the Agent endpoints
type Agent struct {
c *Client
// cache the node name
nodeName string
}
// Agent returns a handle to the agent endpoints
func (c *Client) Agent() *Agent {
return &Agent{c: c}
}
// Self is used to query the agent we are speaking to for
// information about itself
func (a *Agent) Self() (map[string]map[string]interface{}, error) {
r := a.c.newRequest("GET", "/v1/agent/self")
_, resp, err := requireOK(a.c.doRequest(r))
if err != nil {
return nil, err
}
defer resp.Body.Close()
var out map[string]map[string]interface{}
if err := decodeBody(resp, &out); err != nil {
return nil, err
}
return out, nil
}
// NodeName is used to get the node name of the agent
func (a *Agent) NodeName() (string, error) {
if a.nodeName != "" {
return a.nodeName, nil
}
info, err := a.Self()
if err != nil {
return "", err
}
name := info["Config"]["NodeName"].(string)
a.nodeName = name
return name, nil
}
// Checks returns the locally registered checks
func (a *Agent) Checks() (map[string]*AgentCheck, error) {
r := a.c.newRequest("GET", "/v1/agent/checks")
_, resp, err := requireOK(a.c.doRequest(r))
if err != nil {
return nil, err
}
defer resp.Body.Close()
var out map[string]*AgentCheck
if err := decodeBody(resp, &out); err != nil {
return nil, err
}
return out, nil
}
// Services returns the locally registered services
func (a *Agent) Services() (map[string]*AgentService, error) {
r := a.c.newRequest("GET", "/v1/agent/services")
_, resp, err := requireOK(a.c.doRequest(r))
if err != nil {
return nil, err
}
defer resp.Body.Close()
var out map[string]*AgentService
if err := decodeBody(resp, &out); err != nil {
return nil, err
}
return out, nil
}
// Members returns the known gossip members. The WAN
// flag can be used to query a server for WAN members.
func (a *Agent) Members(wan bool) ([]*AgentMember, error) {
r := a.c.newRequest("GET", "/v1/agent/members")
if wan {
r.params.Set("wan", "1")
}
_, resp, err := requireOK(a.c.doRequest(r))
if err != nil {
return nil, err
}
defer resp.Body.Close()
var out []*AgentMember
if err := decodeBody(resp, &out); err != nil {
return nil, err
}
return out, nil
}
// ServiceRegister is used to register a new service with
// the local agent
func (a *Agent) ServiceRegister(service *AgentServiceRegistration) error {
r := a.c.newRequest("PUT", "/v1/agent/service/register")
r.obj = service
_, resp, err := requireOK(a.c.doRequest(r))
if err != nil {
return err
}
resp.Body.Close()
return nil
}
// ServiceDeregister is used to deregister a service with
// the local agent
func (a *Agent) ServiceDeregister(serviceID string) error {
r := a.c.newRequest("PUT", "/v1/agent/service/deregister/"+serviceID)
_, resp, err := requireOK(a.c.doRequest(r))
if err != nil {
return err
}
resp.Body.Close()
return nil
}
// PassTTL is used to set a TTL check to the passing state
func (a *Agent) PassTTL(checkID, note string) error {
return a.UpdateTTL(checkID, note, "pass")
}
// WarnTTL is used to set a TTL check to the warning state
func (a *Agent) WarnTTL(checkID, note string) error {
return a.UpdateTTL(checkID, note, "warn")
}
// FailTTL is used to set a TTL check to the failing state
func (a *Agent) FailTTL(checkID, note string) error {
return a.UpdateTTL(checkID, note, "fail")
}
// UpdateTTL is used to update the TTL of a check
func (a *Agent) UpdateTTL(checkID, note, status string) error {
switch status {
case "pass":
case "warn":
case "fail":
default:
return fmt.Errorf("Invalid status: %s", status)
}
endpoint := fmt.Sprintf("/v1/agent/check/%s/%s", status, checkID)
r := a.c.newRequest("PUT", endpoint)
r.params.Set("note", note)
_, resp, err := requireOK(a.c.doRequest(r))
if err != nil {
return err
}
resp.Body.Close()
return nil
}
// CheckRegister is used to register a new check with
// the local agent
func (a *Agent) CheckRegister(check *AgentCheckRegistration) error {
r := a.c.newRequest("PUT", "/v1/agent/check/register")
r.obj = check
_, resp, err := requireOK(a.c.doRequest(r))
if err != nil {
return err
}
resp.Body.Close()
return nil
}
// CheckDeregister is used to deregister a check with
// the local agent
func (a *Agent) CheckDeregister(checkID string) error {
r := a.c.newRequest("PUT", "/v1/agent/check/deregister/"+checkID)
_, resp, err := requireOK(a.c.doRequest(r))
if err != nil {
return err
}
resp.Body.Close()
return nil
}
// Join is used to instruct the agent to attempt a join to
// another cluster member
func (a *Agent) Join(addr string, wan bool) error {
r := a.c.newRequest("PUT", "/v1/agent/join/"+addr)
if wan {
r.params.Set("wan", "1")
}
_, resp, err := requireOK(a.c.doRequest(r))
if err != nil {
return err
}
resp.Body.Close()
return nil
}
// ForceLeave is used to have the agent eject a failed node
func (a *Agent) ForceLeave(node string) error {
r := a.c.newRequest("PUT", "/v1/agent/force-leave/"+node)
_, resp, err := requireOK(a.c.doRequest(r))
if err != nil {
return err
}
resp.Body.Close()
return nil
}
// EnableServiceMaintenance toggles service maintenance mode on
// for the given service ID.
func (a *Agent) EnableServiceMaintenance(serviceID, reason string) error {
r := a.c.newRequest("PUT", "/v1/agent/service/maintenance/"+serviceID)
r.params.Set("enable", "true")
r.params.Set("reason", reason)
_, resp, err := requireOK(a.c.doRequest(r))
if err != nil {
return err
}
resp.Body.Close()
return nil
}
// DisableServiceMaintenance toggles service maintenance mode off
// for the given service ID.
func (a *Agent) DisableServiceMaintenance(serviceID string) error {
r := a.c.newRequest("PUT", "/v1/agent/service/maintenance/"+serviceID)
r.params.Set("enable", "false")
_, resp, err := requireOK(a.c.doRequest(r))
if err != nil {
return err
}
resp.Body.Close()
return nil
}
// EnableNodeMaintenance toggles node maintenance mode on for the
// agent we are connected to.
func (a *Agent) EnableNodeMaintenance(reason string) error {
r := a.c.newRequest("PUT", "/v1/agent/maintenance")
r.params.Set("enable", "true")
r.params.Set("reason", reason)
_, resp, err := requireOK(a.c.doRequest(r))
if err != nil {
return err
}
resp.Body.Close()
return nil
}
// DisableNodeMaintenance toggles node maintenance mode off for the
// agent we are connected to.
func (a *Agent) DisableNodeMaintenance() error {
r := a.c.newRequest("PUT", "/v1/agent/maintenance")
r.params.Set("enable", "false")
_, resp, err := requireOK(a.c.doRequest(r))
if err != nil {
return err
}
resp.Body.Close()
return nil
}

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@ -1,442 +0,0 @@
package api
import (
"bytes"
"crypto/tls"
"encoding/json"
"fmt"
"io"
"log"
"net"
"net/http"
"net/url"
"os"
"strconv"
"strings"
"time"
)
// QueryOptions are used to parameterize a query
type QueryOptions struct {
// Providing a datacenter overwrites the DC provided
// by the Config
Datacenter string
// AllowStale allows any Consul server (non-leader) to service
// a read. This allows for lower latency and higher throughput
AllowStale bool
// RequireConsistent forces the read to be fully consistent.
// This is more expensive but prevents ever performing a stale
// read.
RequireConsistent bool
// WaitIndex is used to enable a blocking query. Waits
// until the timeout or the next index is reached
WaitIndex uint64
// WaitTime is used to bound the duration of a wait.
// Defaults to that of the Config, but can be overriden.
WaitTime time.Duration
// Token is used to provide a per-request ACL token
// which overrides the agent's default token.
Token string
}
// WriteOptions are used to parameterize a write
type WriteOptions struct {
// Providing a datacenter overwrites the DC provided
// by the Config
Datacenter string
// Token is used to provide a per-request ACL token
// which overrides the agent's default token.
Token string
}
// QueryMeta is used to return meta data about a query
type QueryMeta struct {
// LastIndex. This can be used as a WaitIndex to perform
// a blocking query
LastIndex uint64
// Time of last contact from the leader for the
// server servicing the request
LastContact time.Duration
// Is there a known leader
KnownLeader bool
// How long did the request take
RequestTime time.Duration
}
// WriteMeta is used to return meta data about a write
type WriteMeta struct {
// How long did the request take
RequestTime time.Duration
}
// HttpBasicAuth is used to authenticate http client with HTTP Basic Authentication
type HttpBasicAuth struct {
// Username to use for HTTP Basic Authentication
Username string
// Password to use for HTTP Basic Authentication
Password string
}
// Config is used to configure the creation of a client
type Config struct {
// Address is the address of the Consul server
Address string
// Scheme is the URI scheme for the Consul server
Scheme string
// Datacenter to use. If not provided, the default agent datacenter is used.
Datacenter string
// HttpClient is the client to use. Default will be
// used if not provided.
HttpClient *http.Client
// HttpAuth is the auth info to use for http access.
HttpAuth *HttpBasicAuth
// WaitTime limits how long a Watch will block. If not provided,
// the agent default values will be used.
WaitTime time.Duration
// Token is used to provide a per-request ACL token
// which overrides the agent's default token.
Token string
}
// DefaultConfig returns a default configuration for the client
func DefaultConfig() *Config {
config := &Config{
Address: "127.0.0.1:8500",
Scheme: "http",
HttpClient: http.DefaultClient,
}
if addr := os.Getenv("CONSUL_HTTP_ADDR"); addr != "" {
config.Address = addr
}
if token := os.Getenv("CONSUL_HTTP_TOKEN"); token != "" {
config.Token = token
}
if auth := os.Getenv("CONSUL_HTTP_AUTH"); auth != "" {
var username, password string
if strings.Contains(auth, ":") {
split := strings.SplitN(auth, ":", 2)
username = split[0]
password = split[1]
} else {
username = auth
}
config.HttpAuth = &HttpBasicAuth{
Username: username,
Password: password,
}
}
if ssl := os.Getenv("CONSUL_HTTP_SSL"); ssl != "" {
enabled, err := strconv.ParseBool(ssl)
if err != nil {
log.Printf("[WARN] client: could not parse CONSUL_HTTP_SSL: %s", err)
}
if enabled {
config.Scheme = "https"
}
}
if verify := os.Getenv("CONSUL_HTTP_SSL_VERIFY"); verify != "" {
doVerify, err := strconv.ParseBool(verify)
if err != nil {
log.Printf("[WARN] client: could not parse CONSUL_HTTP_SSL_VERIFY: %s", err)
}
if !doVerify {
config.HttpClient.Transport = &http.Transport{
TLSClientConfig: &tls.Config{
InsecureSkipVerify: true,
},
}
}
}
return config
}
// Client provides a client to the Consul API
type Client struct {
config Config
}
// NewClient returns a new client
func NewClient(config *Config) (*Client, error) {
// bootstrap the config
defConfig := DefaultConfig()
if len(config.Address) == 0 {
config.Address = defConfig.Address
}
if len(config.Scheme) == 0 {
config.Scheme = defConfig.Scheme
}
if config.HttpClient == nil {
config.HttpClient = defConfig.HttpClient
}
if parts := strings.SplitN(config.Address, "unix://", 2); len(parts) == 2 {
config.HttpClient = &http.Client{
Transport: &http.Transport{
Dial: func(_, _ string) (net.Conn, error) {
return net.Dial("unix", parts[1])
},
},
}
config.Address = parts[1]
}
client := &Client{
config: *config,
}
return client, nil
}
// request is used to help build up a request
type request struct {
config *Config
method string
url *url.URL
params url.Values
body io.Reader
obj interface{}
}
// setQueryOptions is used to annotate the request with
// additional query options
func (r *request) setQueryOptions(q *QueryOptions) {
if q == nil {
return
}
if q.Datacenter != "" {
r.params.Set("dc", q.Datacenter)
}
if q.AllowStale {
r.params.Set("stale", "")
}
if q.RequireConsistent {
r.params.Set("consistent", "")
}
if q.WaitIndex != 0 {
r.params.Set("index", strconv.FormatUint(q.WaitIndex, 10))
}
if q.WaitTime != 0 {
r.params.Set("wait", durToMsec(q.WaitTime))
}
if q.Token != "" {
r.params.Set("token", q.Token)
}
}
// durToMsec converts a duration to a millisecond specified string
func durToMsec(dur time.Duration) string {
return fmt.Sprintf("%dms", dur/time.Millisecond)
}
// setWriteOptions is used to annotate the request with
// additional write options
func (r *request) setWriteOptions(q *WriteOptions) {
if q == nil {
return
}
if q.Datacenter != "" {
r.params.Set("dc", q.Datacenter)
}
if q.Token != "" {
r.params.Set("token", q.Token)
}
}
// toHTTP converts the request to an HTTP request
func (r *request) toHTTP() (*http.Request, error) {
// Encode the query parameters
r.url.RawQuery = r.params.Encode()
// Check if we should encode the body
if r.body == nil && r.obj != nil {
if b, err := encodeBody(r.obj); err != nil {
return nil, err
} else {
r.body = b
}
}
// Create the HTTP request
req, err := http.NewRequest(r.method, r.url.RequestURI(), r.body)
if err != nil {
return nil, err
}
req.URL.Host = r.url.Host
req.URL.Scheme = r.url.Scheme
req.Host = r.url.Host
// Setup auth
if r.config.HttpAuth != nil {
req.SetBasicAuth(r.config.HttpAuth.Username, r.config.HttpAuth.Password)
}
return req, nil
}
// newRequest is used to create a new request
func (c *Client) newRequest(method, path string) *request {
r := &request{
config: &c.config,
method: method,
url: &url.URL{
Scheme: c.config.Scheme,
Host: c.config.Address,
Path: path,
},
params: make(map[string][]string),
}
if c.config.Datacenter != "" {
r.params.Set("dc", c.config.Datacenter)
}
if c.config.WaitTime != 0 {
r.params.Set("wait", durToMsec(r.config.WaitTime))
}
if c.config.Token != "" {
r.params.Set("token", r.config.Token)
}
return r
}
// doRequest runs a request with our client
func (c *Client) doRequest(r *request) (time.Duration, *http.Response, error) {
req, err := r.toHTTP()
if err != nil {
return 0, nil, err
}
start := time.Now()
resp, err := c.config.HttpClient.Do(req)
diff := time.Now().Sub(start)
return diff, resp, err
}
// Query is used to do a GET request against an endpoint
// and deserialize the response into an interface using
// standard Consul conventions.
func (c *Client) query(endpoint string, out interface{}, q *QueryOptions) (*QueryMeta, error) {
r := c.newRequest("GET", endpoint)
r.setQueryOptions(q)
rtt, resp, err := requireOK(c.doRequest(r))
if err != nil {
return nil, err
}
defer resp.Body.Close()
qm := &QueryMeta{}
parseQueryMeta(resp, qm)
qm.RequestTime = rtt
if err := decodeBody(resp, out); err != nil {
return nil, err
}
return qm, nil
}
// write is used to do a PUT request against an endpoint
// and serialize/deserialized using the standard Consul conventions.
func (c *Client) write(endpoint string, in, out interface{}, q *WriteOptions) (*WriteMeta, error) {
r := c.newRequest("PUT", endpoint)
r.setWriteOptions(q)
r.obj = in
rtt, resp, err := requireOK(c.doRequest(r))
if err != nil {
return nil, err
}
defer resp.Body.Close()
wm := &WriteMeta{RequestTime: rtt}
if out != nil {
if err := decodeBody(resp, &out); err != nil {
return nil, err
}
}
return wm, nil
}
// parseQueryMeta is used to help parse query meta-data
func parseQueryMeta(resp *http.Response, q *QueryMeta) error {
header := resp.Header
// Parse the X-Consul-Index
index, err := strconv.ParseUint(header.Get("X-Consul-Index"), 10, 64)
if err != nil {
return fmt.Errorf("Failed to parse X-Consul-Index: %v", err)
}
q.LastIndex = index
// Parse the X-Consul-LastContact
last, err := strconv.ParseUint(header.Get("X-Consul-LastContact"), 10, 64)
if err != nil {
return fmt.Errorf("Failed to parse X-Consul-LastContact: %v", err)
}
q.LastContact = time.Duration(last) * time.Millisecond
// Parse the X-Consul-KnownLeader
switch header.Get("X-Consul-KnownLeader") {
case "true":
q.KnownLeader = true
default:
q.KnownLeader = false
}
return nil
}
// decodeBody is used to JSON decode a body
func decodeBody(resp *http.Response, out interface{}) error {
dec := json.NewDecoder(resp.Body)
return dec.Decode(out)
}
// encodeBody is used to encode a request body
func encodeBody(obj interface{}) (io.Reader, error) {
buf := bytes.NewBuffer(nil)
enc := json.NewEncoder(buf)
if err := enc.Encode(obj); err != nil {
return nil, err
}
return buf, nil
}
// requireOK is used to wrap doRequest and check for a 200
func requireOK(d time.Duration, resp *http.Response, e error) (time.Duration, *http.Response, error) {
if e != nil {
if resp != nil {
resp.Body.Close()
}
return d, nil, e
}
if resp.StatusCode != 200 {
var buf bytes.Buffer
io.Copy(&buf, resp.Body)
resp.Body.Close()
return d, nil, fmt.Errorf("Unexpected response code: %d (%s)", resp.StatusCode, buf.Bytes())
}
return d, resp, nil
}

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@ -1,182 +0,0 @@
package api
type Node struct {
Node string
Address string
}
type CatalogService struct {
Node string
Address string
ServiceID string
ServiceName string
ServiceAddress string
ServiceTags []string
ServicePort int
}
type CatalogNode struct {
Node *Node
Services map[string]*AgentService
}
type CatalogRegistration struct {
Node string
Address string
Datacenter string
Service *AgentService
Check *AgentCheck
}
type CatalogDeregistration struct {
Node string
Address string
Datacenter string
ServiceID string
CheckID string
}
// Catalog can be used to query the Catalog endpoints
type Catalog struct {
c *Client
}
// Catalog returns a handle to the catalog endpoints
func (c *Client) Catalog() *Catalog {
return &Catalog{c}
}
func (c *Catalog) Register(reg *CatalogRegistration, q *WriteOptions) (*WriteMeta, error) {
r := c.c.newRequest("PUT", "/v1/catalog/register")
r.setWriteOptions(q)
r.obj = reg
rtt, resp, err := requireOK(c.c.doRequest(r))
if err != nil {
return nil, err
}
resp.Body.Close()
wm := &WriteMeta{}
wm.RequestTime = rtt
return wm, nil
}
func (c *Catalog) Deregister(dereg *CatalogDeregistration, q *WriteOptions) (*WriteMeta, error) {
r := c.c.newRequest("PUT", "/v1/catalog/deregister")
r.setWriteOptions(q)
r.obj = dereg
rtt, resp, err := requireOK(c.c.doRequest(r))
if err != nil {
return nil, err
}
resp.Body.Close()
wm := &WriteMeta{}
wm.RequestTime = rtt
return wm, nil
}
// Datacenters is used to query for all the known datacenters
func (c *Catalog) Datacenters() ([]string, error) {
r := c.c.newRequest("GET", "/v1/catalog/datacenters")
_, resp, err := requireOK(c.c.doRequest(r))
if err != nil {
return nil, err
}
defer resp.Body.Close()
var out []string
if err := decodeBody(resp, &out); err != nil {
return nil, err
}
return out, nil
}
// Nodes is used to query all the known nodes
func (c *Catalog) Nodes(q *QueryOptions) ([]*Node, *QueryMeta, error) {
r := c.c.newRequest("GET", "/v1/catalog/nodes")
r.setQueryOptions(q)
rtt, resp, err := requireOK(c.c.doRequest(r))
if err != nil {
return nil, nil, err
}
defer resp.Body.Close()
qm := &QueryMeta{}
parseQueryMeta(resp, qm)
qm.RequestTime = rtt
var out []*Node
if err := decodeBody(resp, &out); err != nil {
return nil, nil, err
}
return out, qm, nil
}
// Services is used to query for all known services
func (c *Catalog) Services(q *QueryOptions) (map[string][]string, *QueryMeta, error) {
r := c.c.newRequest("GET", "/v1/catalog/services")
r.setQueryOptions(q)
rtt, resp, err := requireOK(c.c.doRequest(r))
if err != nil {
return nil, nil, err
}
defer resp.Body.Close()
qm := &QueryMeta{}
parseQueryMeta(resp, qm)
qm.RequestTime = rtt
var out map[string][]string
if err := decodeBody(resp, &out); err != nil {
return nil, nil, err
}
return out, qm, nil
}
// Service is used to query catalog entries for a given service
func (c *Catalog) Service(service, tag string, q *QueryOptions) ([]*CatalogService, *QueryMeta, error) {
r := c.c.newRequest("GET", "/v1/catalog/service/"+service)
r.setQueryOptions(q)
if tag != "" {
r.params.Set("tag", tag)
}
rtt, resp, err := requireOK(c.c.doRequest(r))
if err != nil {
return nil, nil, err
}
defer resp.Body.Close()
qm := &QueryMeta{}
parseQueryMeta(resp, qm)
qm.RequestTime = rtt
var out []*CatalogService
if err := decodeBody(resp, &out); err != nil {
return nil, nil, err
}
return out, qm, nil
}
// Node is used to query for service information about a single node
func (c *Catalog) Node(node string, q *QueryOptions) (*CatalogNode, *QueryMeta, error) {
r := c.c.newRequest("GET", "/v1/catalog/node/"+node)
r.setQueryOptions(q)
rtt, resp, err := requireOK(c.c.doRequest(r))
if err != nil {
return nil, nil, err
}
defer resp.Body.Close()
qm := &QueryMeta{}
parseQueryMeta(resp, qm)
qm.RequestTime = rtt
var out *CatalogNode
if err := decodeBody(resp, &out); err != nil {
return nil, nil, err
}
return out, qm, nil
}

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@ -1,104 +0,0 @@
package api
import (
"bytes"
"strconv"
)
// Event can be used to query the Event endpoints
type Event struct {
c *Client
}
// UserEvent represents an event that was fired by the user
type UserEvent struct {
ID string
Name string
Payload []byte
NodeFilter string
ServiceFilter string
TagFilter string
Version int
LTime uint64
}
// Event returns a handle to the event endpoints
func (c *Client) Event() *Event {
return &Event{c}
}
// Fire is used to fire a new user event. Only the Name, Payload and Filters
// are respected. This returns the ID or an associated error. Cross DC requests
// are supported.
func (e *Event) Fire(params *UserEvent, q *WriteOptions) (string, *WriteMeta, error) {
r := e.c.newRequest("PUT", "/v1/event/fire/"+params.Name)
r.setWriteOptions(q)
if params.NodeFilter != "" {
r.params.Set("node", params.NodeFilter)
}
if params.ServiceFilter != "" {
r.params.Set("service", params.ServiceFilter)
}
if params.TagFilter != "" {
r.params.Set("tag", params.TagFilter)
}
if params.Payload != nil {
r.body = bytes.NewReader(params.Payload)
}
rtt, resp, err := requireOK(e.c.doRequest(r))
if err != nil {
return "", nil, err
}
defer resp.Body.Close()
wm := &WriteMeta{RequestTime: rtt}
var out UserEvent
if err := decodeBody(resp, &out); err != nil {
return "", nil, err
}
return out.ID, wm, nil
}
// List is used to get the most recent events an agent has received.
// This list can be optionally filtered by the name. This endpoint supports
// quasi-blocking queries. The index is not monotonic, nor does it provide provide
// LastContact or KnownLeader.
func (e *Event) List(name string, q *QueryOptions) ([]*UserEvent, *QueryMeta, error) {
r := e.c.newRequest("GET", "/v1/event/list")
r.setQueryOptions(q)
if name != "" {
r.params.Set("name", name)
}
rtt, resp, err := requireOK(e.c.doRequest(r))
if err != nil {
return nil, nil, err
}
defer resp.Body.Close()
qm := &QueryMeta{}
parseQueryMeta(resp, qm)
qm.RequestTime = rtt
var entries []*UserEvent
if err := decodeBody(resp, &entries); err != nil {
return nil, nil, err
}
return entries, qm, nil
}
// IDToIndex is a bit of a hack. This simulates the index generation to
// convert an event ID into a WaitIndex.
func (e *Event) IDToIndex(uuid string) uint64 {
lower := uuid[0:8] + uuid[9:13] + uuid[14:18]
upper := uuid[19:23] + uuid[24:36]
lowVal, err := strconv.ParseUint(lower, 16, 64)
if err != nil {
panic("Failed to convert " + lower)
}
highVal, err := strconv.ParseUint(upper, 16, 64)
if err != nil {
panic("Failed to convert " + upper)
}
return lowVal ^ highVal
}

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@ -1,136 +0,0 @@
package api
import (
"fmt"
)
// HealthCheck is used to represent a single check
type HealthCheck struct {
Node string
CheckID string
Name string
Status string
Notes string
Output string
ServiceID string
ServiceName string
}
// ServiceEntry is used for the health service endpoint
type ServiceEntry struct {
Node *Node
Service *AgentService
Checks []*HealthCheck
}
// Health can be used to query the Health endpoints
type Health struct {
c *Client
}
// Health returns a handle to the health endpoints
func (c *Client) Health() *Health {
return &Health{c}
}
// Node is used to query for checks belonging to a given node
func (h *Health) Node(node string, q *QueryOptions) ([]*HealthCheck, *QueryMeta, error) {
r := h.c.newRequest("GET", "/v1/health/node/"+node)
r.setQueryOptions(q)
rtt, resp, err := requireOK(h.c.doRequest(r))
if err != nil {
return nil, nil, err
}
defer resp.Body.Close()
qm := &QueryMeta{}
parseQueryMeta(resp, qm)
qm.RequestTime = rtt
var out []*HealthCheck
if err := decodeBody(resp, &out); err != nil {
return nil, nil, err
}
return out, qm, nil
}
// Checks is used to return the checks associated with a service
func (h *Health) Checks(service string, q *QueryOptions) ([]*HealthCheck, *QueryMeta, error) {
r := h.c.newRequest("GET", "/v1/health/checks/"+service)
r.setQueryOptions(q)
rtt, resp, err := requireOK(h.c.doRequest(r))
if err != nil {
return nil, nil, err
}
defer resp.Body.Close()
qm := &QueryMeta{}
parseQueryMeta(resp, qm)
qm.RequestTime = rtt
var out []*HealthCheck
if err := decodeBody(resp, &out); err != nil {
return nil, nil, err
}
return out, qm, nil
}
// Service is used to query health information along with service info
// for a given service. It can optionally do server-side filtering on a tag
// or nodes with passing health checks only.
func (h *Health) Service(service, tag string, passingOnly bool, q *QueryOptions) ([]*ServiceEntry, *QueryMeta, error) {
r := h.c.newRequest("GET", "/v1/health/service/"+service)
r.setQueryOptions(q)
if tag != "" {
r.params.Set("tag", tag)
}
if passingOnly {
r.params.Set("passing", "1")
}
rtt, resp, err := requireOK(h.c.doRequest(r))
if err != nil {
return nil, nil, err
}
defer resp.Body.Close()
qm := &QueryMeta{}
parseQueryMeta(resp, qm)
qm.RequestTime = rtt
var out []*ServiceEntry
if err := decodeBody(resp, &out); err != nil {
return nil, nil, err
}
return out, qm, nil
}
// State is used to retreive all the checks in a given state.
// The wildcard "any" state can also be used for all checks.
func (h *Health) State(state string, q *QueryOptions) ([]*HealthCheck, *QueryMeta, error) {
switch state {
case "any":
case "warning":
case "critical":
case "passing":
case "unknown":
default:
return nil, nil, fmt.Errorf("Unsupported state: %v", state)
}
r := h.c.newRequest("GET", "/v1/health/state/"+state)
r.setQueryOptions(q)
rtt, resp, err := requireOK(h.c.doRequest(r))
if err != nil {
return nil, nil, err
}
defer resp.Body.Close()
qm := &QueryMeta{}
parseQueryMeta(resp, qm)
qm.RequestTime = rtt
var out []*HealthCheck
if err := decodeBody(resp, &out); err != nil {
return nil, nil, err
}
return out, qm, nil
}

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@ -1,236 +0,0 @@
package api
import (
"bytes"
"fmt"
"io"
"net/http"
"strconv"
"strings"
)
// KVPair is used to represent a single K/V entry
type KVPair struct {
Key string
CreateIndex uint64
ModifyIndex uint64
LockIndex uint64
Flags uint64
Value []byte
Session string
}
// KVPairs is a list of KVPair objects
type KVPairs []*KVPair
// KV is used to manipulate the K/V API
type KV struct {
c *Client
}
// KV is used to return a handle to the K/V apis
func (c *Client) KV() *KV {
return &KV{c}
}
// Get is used to lookup a single key
func (k *KV) Get(key string, q *QueryOptions) (*KVPair, *QueryMeta, error) {
resp, qm, err := k.getInternal(key, nil, q)
if err != nil {
return nil, nil, err
}
if resp == nil {
return nil, qm, nil
}
defer resp.Body.Close()
var entries []*KVPair
if err := decodeBody(resp, &entries); err != nil {
return nil, nil, err
}
if len(entries) > 0 {
return entries[0], qm, nil
}
return nil, qm, nil
}
// List is used to lookup all keys under a prefix
func (k *KV) List(prefix string, q *QueryOptions) (KVPairs, *QueryMeta, error) {
resp, qm, err := k.getInternal(prefix, map[string]string{"recurse": ""}, q)
if err != nil {
return nil, nil, err
}
if resp == nil {
return nil, qm, nil
}
defer resp.Body.Close()
var entries []*KVPair
if err := decodeBody(resp, &entries); err != nil {
return nil, nil, err
}
return entries, qm, nil
}
// Keys is used to list all the keys under a prefix. Optionally,
// a separator can be used to limit the responses.
func (k *KV) Keys(prefix, separator string, q *QueryOptions) ([]string, *QueryMeta, error) {
params := map[string]string{"keys": ""}
if separator != "" {
params["separator"] = separator
}
resp, qm, err := k.getInternal(prefix, params, q)
if err != nil {
return nil, nil, err
}
if resp == nil {
return nil, qm, nil
}
defer resp.Body.Close()
var entries []string
if err := decodeBody(resp, &entries); err != nil {
return nil, nil, err
}
return entries, qm, nil
}
func (k *KV) getInternal(key string, params map[string]string, q *QueryOptions) (*http.Response, *QueryMeta, error) {
r := k.c.newRequest("GET", "/v1/kv/"+key)
r.setQueryOptions(q)
for param, val := range params {
r.params.Set(param, val)
}
rtt, resp, err := k.c.doRequest(r)
if err != nil {
return nil, nil, err
}
qm := &QueryMeta{}
parseQueryMeta(resp, qm)
qm.RequestTime = rtt
if resp.StatusCode == 404 {
resp.Body.Close()
return nil, qm, nil
} else if resp.StatusCode != 200 {
resp.Body.Close()
return nil, nil, fmt.Errorf("Unexpected response code: %d", resp.StatusCode)
}
return resp, qm, nil
}
// Put is used to write a new value. Only the
// Key, Flags and Value is respected.
func (k *KV) Put(p *KVPair, q *WriteOptions) (*WriteMeta, error) {
params := make(map[string]string, 1)
if p.Flags != 0 {
params["flags"] = strconv.FormatUint(p.Flags, 10)
}
_, wm, err := k.put(p.Key, params, p.Value, q)
return wm, err
}
// CAS is used for a Check-And-Set operation. The Key,
// ModifyIndex, Flags and Value are respected. Returns true
// on success or false on failures.
func (k *KV) CAS(p *KVPair, q *WriteOptions) (bool, *WriteMeta, error) {
params := make(map[string]string, 2)
if p.Flags != 0 {
params["flags"] = strconv.FormatUint(p.Flags, 10)
}
params["cas"] = strconv.FormatUint(p.ModifyIndex, 10)
return k.put(p.Key, params, p.Value, q)
}
// Acquire is used for a lock acquisiiton operation. The Key,
// Flags, Value and Session are respected. Returns true
// on success or false on failures.
func (k *KV) Acquire(p *KVPair, q *WriteOptions) (bool, *WriteMeta, error) {
params := make(map[string]string, 2)
if p.Flags != 0 {
params["flags"] = strconv.FormatUint(p.Flags, 10)
}
params["acquire"] = p.Session
return k.put(p.Key, params, p.Value, q)
}
// Release is used for a lock release operation. The Key,
// Flags, Value and Session are respected. Returns true
// on success or false on failures.
func (k *KV) Release(p *KVPair, q *WriteOptions) (bool, *WriteMeta, error) {
params := make(map[string]string, 2)
if p.Flags != 0 {
params["flags"] = strconv.FormatUint(p.Flags, 10)
}
params["release"] = p.Session
return k.put(p.Key, params, p.Value, q)
}
func (k *KV) put(key string, params map[string]string, body []byte, q *WriteOptions) (bool, *WriteMeta, error) {
r := k.c.newRequest("PUT", "/v1/kv/"+key)
r.setWriteOptions(q)
for param, val := range params {
r.params.Set(param, val)
}
r.body = bytes.NewReader(body)
rtt, resp, err := requireOK(k.c.doRequest(r))
if err != nil {
return false, nil, err
}
defer resp.Body.Close()
qm := &WriteMeta{}
qm.RequestTime = rtt
var buf bytes.Buffer
if _, err := io.Copy(&buf, resp.Body); err != nil {
return false, nil, fmt.Errorf("Failed to read response: %v", err)
}
res := strings.Contains(string(buf.Bytes()), "true")
return res, qm, nil
}
// Delete is used to delete a single key
func (k *KV) Delete(key string, w *WriteOptions) (*WriteMeta, error) {
_, qm, err := k.deleteInternal(key, nil, w)
return qm, err
}
// DeleteCAS is used for a Delete Check-And-Set operation. The Key
// and ModifyIndex are respected. Returns true on success or false on failures.
func (k *KV) DeleteCAS(p *KVPair, q *WriteOptions) (bool, *WriteMeta, error) {
params := map[string]string{
"cas": strconv.FormatUint(p.ModifyIndex, 10),
}
return k.deleteInternal(p.Key, params, q)
}
// DeleteTree is used to delete all keys under a prefix
func (k *KV) DeleteTree(prefix string, w *WriteOptions) (*WriteMeta, error) {
_, qm, err := k.deleteInternal(prefix, map[string]string{"recurse": ""}, w)
return qm, err
}
func (k *KV) deleteInternal(key string, params map[string]string, q *WriteOptions) (bool, *WriteMeta, error) {
r := k.c.newRequest("DELETE", "/v1/kv/"+key)
r.setWriteOptions(q)
for param, val := range params {
r.params.Set(param, val)
}
rtt, resp, err := requireOK(k.c.doRequest(r))
if err != nil {
return false, nil, err
}
defer resp.Body.Close()
qm := &WriteMeta{}
qm.RequestTime = rtt
var buf bytes.Buffer
if _, err := io.Copy(&buf, resp.Body); err != nil {
return false, nil, fmt.Errorf("Failed to read response: %v", err)
}
res := strings.Contains(string(buf.Bytes()), "true")
return res, qm, nil
}

View File

@ -1,326 +0,0 @@
package api
import (
"fmt"
"sync"
"time"
)
const (
// DefaultLockSessionName is the Session Name we assign if none is provided
DefaultLockSessionName = "Consul API Lock"
// DefaultLockSessionTTL is the default session TTL if no Session is provided
// when creating a new Lock. This is used because we do not have another
// other check to depend upon.
DefaultLockSessionTTL = "15s"
// DefaultLockWaitTime is how long we block for at a time to check if lock
// acquisition is possible. This affects the minimum time it takes to cancel
// a Lock acquisition.
DefaultLockWaitTime = 15 * time.Second
// DefaultLockRetryTime is how long we wait after a failed lock acquisition
// before attempting to do the lock again. This is so that once a lock-delay
// is in affect, we do not hot loop retrying the acquisition.
DefaultLockRetryTime = 5 * time.Second
// LockFlagValue is a magic flag we set to indicate a key
// is being used for a lock. It is used to detect a potential
// conflict with a semaphore.
LockFlagValue = 0x2ddccbc058a50c18
)
var (
// ErrLockHeld is returned if we attempt to double lock
ErrLockHeld = fmt.Errorf("Lock already held")
// ErrLockNotHeld is returned if we attempt to unlock a lock
// that we do not hold.
ErrLockNotHeld = fmt.Errorf("Lock not held")
// ErrLockInUse is returned if we attempt to destroy a lock
// that is in use.
ErrLockInUse = fmt.Errorf("Lock in use")
// ErrLockConflict is returned if the flags on a key
// used for a lock do not match expectation
ErrLockConflict = fmt.Errorf("Existing key does not match lock use")
)
// Lock is used to implement client-side leader election. It is follows the
// algorithm as described here: https://consul.io/docs/guides/leader-election.html.
type Lock struct {
c *Client
opts *LockOptions
isHeld bool
sessionRenew chan struct{}
lockSession string
l sync.Mutex
}
// LockOptions is used to parameterize the Lock behavior.
type LockOptions struct {
Key string // Must be set and have write permissions
Value []byte // Optional, value to associate with the lock
Session string // Optional, created if not specified
SessionName string // Optional, defaults to DefaultLockSessionName
SessionTTL string // Optional, defaults to DefaultLockSessionTTL
}
// LockKey returns a handle to a lock struct which can be used
// to acquire and release the mutex. The key used must have
// write permissions.
func (c *Client) LockKey(key string) (*Lock, error) {
opts := &LockOptions{
Key: key,
}
return c.LockOpts(opts)
}
// LockOpts returns a handle to a lock struct which can be used
// to acquire and release the mutex. The key used must have
// write permissions.
func (c *Client) LockOpts(opts *LockOptions) (*Lock, error) {
if opts.Key == "" {
return nil, fmt.Errorf("missing key")
}
if opts.SessionName == "" {
opts.SessionName = DefaultLockSessionName
}
if opts.SessionTTL == "" {
opts.SessionTTL = DefaultLockSessionTTL
} else {
if _, err := time.ParseDuration(opts.SessionTTL); err != nil {
return nil, fmt.Errorf("invalid SessionTTL: %v", err)
}
}
l := &Lock{
c: c,
opts: opts,
}
return l, nil
}
// Lock attempts to acquire the lock and blocks while doing so.
// Providing a non-nil stopCh can be used to abort the lock attempt.
// Returns a channel that is closed if our lock is lost or an error.
// This channel could be closed at any time due to session invalidation,
// communication errors, operator intervention, etc. It is NOT safe to
// assume that the lock is held until Unlock() unless the Session is specifically
// created without any associated health checks. By default Consul sessions
// prefer liveness over safety and an application must be able to handle
// the lock being lost.
func (l *Lock) Lock(stopCh <-chan struct{}) (<-chan struct{}, error) {
// Hold the lock as we try to acquire
l.l.Lock()
defer l.l.Unlock()
// Check if we already hold the lock
if l.isHeld {
return nil, ErrLockHeld
}
// Check if we need to create a session first
l.lockSession = l.opts.Session
if l.lockSession == "" {
if s, err := l.createSession(); err != nil {
return nil, fmt.Errorf("failed to create session: %v", err)
} else {
l.sessionRenew = make(chan struct{})
l.lockSession = s
session := l.c.Session()
go session.RenewPeriodic(l.opts.SessionTTL, s, nil, l.sessionRenew)
// If we fail to acquire the lock, cleanup the session
defer func() {
if !l.isHeld {
close(l.sessionRenew)
l.sessionRenew = nil
}
}()
}
}
// Setup the query options
kv := l.c.KV()
qOpts := &QueryOptions{
WaitTime: DefaultLockWaitTime,
}
WAIT:
// Check if we should quit
select {
case <-stopCh:
return nil, nil
default:
}
// Look for an existing lock, blocking until not taken
pair, meta, err := kv.Get(l.opts.Key, qOpts)
if err != nil {
return nil, fmt.Errorf("failed to read lock: %v", err)
}
if pair != nil && pair.Flags != LockFlagValue {
return nil, ErrLockConflict
}
locked := false
if pair != nil && pair.Session == l.lockSession {
goto HELD
}
if pair != nil && pair.Session != "" {
qOpts.WaitIndex = meta.LastIndex
goto WAIT
}
// Try to acquire the lock
pair = l.lockEntry(l.lockSession)
locked, _, err = kv.Acquire(pair, nil)
if err != nil {
return nil, fmt.Errorf("failed to acquire lock: %v", err)
}
// Handle the case of not getting the lock
if !locked {
select {
case <-time.After(DefaultLockRetryTime):
goto WAIT
case <-stopCh:
return nil, nil
}
}
HELD:
// Watch to ensure we maintain leadership
leaderCh := make(chan struct{})
go l.monitorLock(l.lockSession, leaderCh)
// Set that we own the lock
l.isHeld = true
// Locked! All done
return leaderCh, nil
}
// Unlock released the lock. It is an error to call this
// if the lock is not currently held.
func (l *Lock) Unlock() error {
// Hold the lock as we try to release
l.l.Lock()
defer l.l.Unlock()
// Ensure the lock is actually held
if !l.isHeld {
return ErrLockNotHeld
}
// Set that we no longer own the lock
l.isHeld = false
// Stop the session renew
if l.sessionRenew != nil {
defer func() {
close(l.sessionRenew)
l.sessionRenew = nil
}()
}
// Get the lock entry, and clear the lock session
lockEnt := l.lockEntry(l.lockSession)
l.lockSession = ""
// Release the lock explicitly
kv := l.c.KV()
_, _, err := kv.Release(lockEnt, nil)
if err != nil {
return fmt.Errorf("failed to release lock: %v", err)
}
return nil
}
// Destroy is used to cleanup the lock entry. It is not necessary
// to invoke. It will fail if the lock is in use.
func (l *Lock) Destroy() error {
// Hold the lock as we try to release
l.l.Lock()
defer l.l.Unlock()
// Check if we already hold the lock
if l.isHeld {
return ErrLockHeld
}
// Look for an existing lock
kv := l.c.KV()
pair, _, err := kv.Get(l.opts.Key, nil)
if err != nil {
return fmt.Errorf("failed to read lock: %v", err)
}
// Nothing to do if the lock does not exist
if pair == nil {
return nil
}
// Check for possible flag conflict
if pair.Flags != LockFlagValue {
return ErrLockConflict
}
// Check if it is in use
if pair.Session != "" {
return ErrLockInUse
}
// Attempt the delete
didRemove, _, err := kv.DeleteCAS(pair, nil)
if err != nil {
return fmt.Errorf("failed to remove lock: %v", err)
}
if !didRemove {
return ErrLockInUse
}
return nil
}
// createSession is used to create a new managed session
func (l *Lock) createSession() (string, error) {
session := l.c.Session()
se := &SessionEntry{
Name: l.opts.SessionName,
TTL: l.opts.SessionTTL,
}
id, _, err := session.Create(se, nil)
if err != nil {
return "", err
}
return id, nil
}
// lockEntry returns a formatted KVPair for the lock
func (l *Lock) lockEntry(session string) *KVPair {
return &KVPair{
Key: l.opts.Key,
Value: l.opts.Value,
Session: session,
Flags: LockFlagValue,
}
}
// monitorLock is a long running routine to monitor a lock ownership
// It closes the stopCh if we lose our leadership.
func (l *Lock) monitorLock(session string, stopCh chan struct{}) {
defer close(stopCh)
kv := l.c.KV()
opts := &QueryOptions{RequireConsistent: true}
WAIT:
pair, meta, err := kv.Get(l.opts.Key, opts)
if err != nil {
return
}
if pair != nil && pair.Session == session {
opts.WaitIndex = meta.LastIndex
goto WAIT
}
}

View File

@ -1,24 +0,0 @@
package api
// Raw can be used to do raw queries against custom endpoints
type Raw struct {
c *Client
}
// Raw returns a handle to query endpoints
func (c *Client) Raw() *Raw {
return &Raw{c}
}
// Query is used to do a GET request against an endpoint
// and deserialize the response into an interface using
// standard Consul conventions.
func (raw *Raw) Query(endpoint string, out interface{}, q *QueryOptions) (*QueryMeta, error) {
return raw.c.query(endpoint, out, q)
}
// Write is used to do a PUT request against an endpoint
// and serialize/deserialized using the standard Consul conventions.
func (raw *Raw) Write(endpoint string, in, out interface{}, q *WriteOptions) (*WriteMeta, error) {
return raw.c.write(endpoint, in, out, q)
}

View File

@ -1,477 +0,0 @@
package api
import (
"encoding/json"
"fmt"
"path"
"sync"
"time"
)
const (
// DefaultSemaphoreSessionName is the Session Name we assign if none is provided
DefaultSemaphoreSessionName = "Consul API Semaphore"
// DefaultSemaphoreSessionTTL is the default session TTL if no Session is provided
// when creating a new Semaphore. This is used because we do not have another
// other check to depend upon.
DefaultSemaphoreSessionTTL = "15s"
// DefaultSemaphoreWaitTime is how long we block for at a time to check if semaphore
// acquisition is possible. This affects the minimum time it takes to cancel
// a Semaphore acquisition.
DefaultSemaphoreWaitTime = 15 * time.Second
// DefaultSemaphoreKey is the key used within the prefix to
// use for coordination between all the contenders.
DefaultSemaphoreKey = ".lock"
// SemaphoreFlagValue is a magic flag we set to indicate a key
// is being used for a semaphore. It is used to detect a potential
// conflict with a lock.
SemaphoreFlagValue = 0xe0f69a2baa414de0
)
var (
// ErrSemaphoreHeld is returned if we attempt to double lock
ErrSemaphoreHeld = fmt.Errorf("Semaphore already held")
// ErrSemaphoreNotHeld is returned if we attempt to unlock a semaphore
// that we do not hold.
ErrSemaphoreNotHeld = fmt.Errorf("Semaphore not held")
// ErrSemaphoreInUse is returned if we attempt to destroy a semaphore
// that is in use.
ErrSemaphoreInUse = fmt.Errorf("Semaphore in use")
// ErrSemaphoreConflict is returned if the flags on a key
// used for a semaphore do not match expectation
ErrSemaphoreConflict = fmt.Errorf("Existing key does not match semaphore use")
)
// Semaphore is used to implement a distributed semaphore
// using the Consul KV primitives.
type Semaphore struct {
c *Client
opts *SemaphoreOptions
isHeld bool
sessionRenew chan struct{}
lockSession string
l sync.Mutex
}
// SemaphoreOptions is used to parameterize the Semaphore
type SemaphoreOptions struct {
Prefix string // Must be set and have write permissions
Limit int // Must be set, and be positive
Value []byte // Optional, value to associate with the contender entry
Session string // OPtional, created if not specified
SessionName string // Optional, defaults to DefaultLockSessionName
SessionTTL string // Optional, defaults to DefaultLockSessionTTL
}
// semaphoreLock is written under the DefaultSemaphoreKey and
// is used to coordinate between all the contenders.
type semaphoreLock struct {
// Limit is the integer limit of holders. This is used to
// verify that all the holders agree on the value.
Limit int
// Holders is a list of all the semaphore holders.
// It maps the session ID to true. It is used as a set effectively.
Holders map[string]bool
}
// SemaphorePrefix is used to created a Semaphore which will operate
// at the given KV prefix and uses the given limit for the semaphore.
// The prefix must have write privileges, and the limit must be agreed
// upon by all contenders.
func (c *Client) SemaphorePrefix(prefix string, limit int) (*Semaphore, error) {
opts := &SemaphoreOptions{
Prefix: prefix,
Limit: limit,
}
return c.SemaphoreOpts(opts)
}
// SemaphoreOpts is used to create a Semaphore with the given options.
// The prefix must have write privileges, and the limit must be agreed
// upon by all contenders. If a Session is not provided, one will be created.
func (c *Client) SemaphoreOpts(opts *SemaphoreOptions) (*Semaphore, error) {
if opts.Prefix == "" {
return nil, fmt.Errorf("missing prefix")
}
if opts.Limit <= 0 {
return nil, fmt.Errorf("semaphore limit must be positive")
}
if opts.SessionName == "" {
opts.SessionName = DefaultSemaphoreSessionName
}
if opts.SessionTTL == "" {
opts.SessionTTL = DefaultSemaphoreSessionTTL
} else {
if _, err := time.ParseDuration(opts.SessionTTL); err != nil {
return nil, fmt.Errorf("invalid SessionTTL: %v", err)
}
}
s := &Semaphore{
c: c,
opts: opts,
}
return s, nil
}
// Acquire attempts to reserve a slot in the semaphore, blocking until
// success, interrupted via the stopCh or an error is encounted.
// Providing a non-nil stopCh can be used to abort the attempt.
// On success, a channel is returned that represents our slot.
// This channel could be closed at any time due to session invalidation,
// communication errors, operator intervention, etc. It is NOT safe to
// assume that the slot is held until Release() unless the Session is specifically
// created without any associated health checks. By default Consul sessions
// prefer liveness over safety and an application must be able to handle
// the session being lost.
func (s *Semaphore) Acquire(stopCh <-chan struct{}) (<-chan struct{}, error) {
// Hold the lock as we try to acquire
s.l.Lock()
defer s.l.Unlock()
// Check if we already hold the semaphore
if s.isHeld {
return nil, ErrSemaphoreHeld
}
// Check if we need to create a session first
s.lockSession = s.opts.Session
if s.lockSession == "" {
if sess, err := s.createSession(); err != nil {
return nil, fmt.Errorf("failed to create session: %v", err)
} else {
s.sessionRenew = make(chan struct{})
s.lockSession = sess
session := s.c.Session()
go session.RenewPeriodic(s.opts.SessionTTL, sess, nil, s.sessionRenew)
// If we fail to acquire the lock, cleanup the session
defer func() {
if !s.isHeld {
close(s.sessionRenew)
s.sessionRenew = nil
}
}()
}
}
// Create the contender entry
kv := s.c.KV()
made, _, err := kv.Acquire(s.contenderEntry(s.lockSession), nil)
if err != nil || !made {
return nil, fmt.Errorf("failed to make contender entry: %v", err)
}
// Setup the query options
qOpts := &QueryOptions{
WaitTime: DefaultSemaphoreWaitTime,
}
WAIT:
// Check if we should quit
select {
case <-stopCh:
return nil, nil
default:
}
// Read the prefix
pairs, meta, err := kv.List(s.opts.Prefix, qOpts)
if err != nil {
return nil, fmt.Errorf("failed to read prefix: %v", err)
}
// Decode the lock
lockPair := s.findLock(pairs)
if lockPair.Flags != SemaphoreFlagValue {
return nil, ErrSemaphoreConflict
}
lock, err := s.decodeLock(lockPair)
if err != nil {
return nil, err
}
// Verify we agree with the limit
if lock.Limit != s.opts.Limit {
return nil, fmt.Errorf("semaphore limit conflict (lock: %d, local: %d)",
lock.Limit, s.opts.Limit)
}
// Prune the dead holders
s.pruneDeadHolders(lock, pairs)
// Check if the lock is held
if len(lock.Holders) >= lock.Limit {
qOpts.WaitIndex = meta.LastIndex
goto WAIT
}
// Create a new lock with us as a holder
lock.Holders[s.lockSession] = true
newLock, err := s.encodeLock(lock, lockPair.ModifyIndex)
if err != nil {
return nil, err
}
// Attempt the acquisition
didSet, _, err := kv.CAS(newLock, nil)
if err != nil {
return nil, fmt.Errorf("failed to update lock: %v", err)
}
if !didSet {
// Update failed, could have been a race with another contender,
// retry the operation
goto WAIT
}
// Watch to ensure we maintain ownership of the slot
lockCh := make(chan struct{})
go s.monitorLock(s.lockSession, lockCh)
// Set that we own the lock
s.isHeld = true
// Acquired! All done
return lockCh, nil
}
// Release is used to voluntarily give up our semaphore slot. It is
// an error to call this if the semaphore has not been acquired.
func (s *Semaphore) Release() error {
// Hold the lock as we try to release
s.l.Lock()
defer s.l.Unlock()
// Ensure the lock is actually held
if !s.isHeld {
return ErrSemaphoreNotHeld
}
// Set that we no longer own the lock
s.isHeld = false
// Stop the session renew
if s.sessionRenew != nil {
defer func() {
close(s.sessionRenew)
s.sessionRenew = nil
}()
}
// Get and clear the lock session
lockSession := s.lockSession
s.lockSession = ""
// Remove ourselves as a lock holder
kv := s.c.KV()
key := path.Join(s.opts.Prefix, DefaultSemaphoreKey)
READ:
pair, _, err := kv.Get(key, nil)
if err != nil {
return err
}
if pair == nil {
pair = &KVPair{}
}
lock, err := s.decodeLock(pair)
if err != nil {
return err
}
// Create a new lock without us as a holder
if _, ok := lock.Holders[lockSession]; ok {
delete(lock.Holders, lockSession)
newLock, err := s.encodeLock(lock, pair.ModifyIndex)
if err != nil {
return err
}
// Swap the locks
didSet, _, err := kv.CAS(newLock, nil)
if err != nil {
return fmt.Errorf("failed to update lock: %v", err)
}
if !didSet {
goto READ
}
}
// Destroy the contender entry
contenderKey := path.Join(s.opts.Prefix, lockSession)
if _, err := kv.Delete(contenderKey, nil); err != nil {
return err
}
return nil
}
// Destroy is used to cleanup the semaphore entry. It is not necessary
// to invoke. It will fail if the semaphore is in use.
func (s *Semaphore) Destroy() error {
// Hold the lock as we try to acquire
s.l.Lock()
defer s.l.Unlock()
// Check if we already hold the semaphore
if s.isHeld {
return ErrSemaphoreHeld
}
// List for the semaphore
kv := s.c.KV()
pairs, _, err := kv.List(s.opts.Prefix, nil)
if err != nil {
return fmt.Errorf("failed to read prefix: %v", err)
}
// Find the lock pair, bail if it doesn't exist
lockPair := s.findLock(pairs)
if lockPair.ModifyIndex == 0 {
return nil
}
if lockPair.Flags != SemaphoreFlagValue {
return ErrSemaphoreConflict
}
// Decode the lock
lock, err := s.decodeLock(lockPair)
if err != nil {
return err
}
// Prune the dead holders
s.pruneDeadHolders(lock, pairs)
// Check if there are any holders
if len(lock.Holders) > 0 {
return ErrSemaphoreInUse
}
// Attempt the delete
didRemove, _, err := kv.DeleteCAS(lockPair, nil)
if err != nil {
return fmt.Errorf("failed to remove semaphore: %v", err)
}
if !didRemove {
return ErrSemaphoreInUse
}
return nil
}
// createSession is used to create a new managed session
func (s *Semaphore) createSession() (string, error) {
session := s.c.Session()
se := &SessionEntry{
Name: s.opts.SessionName,
TTL: s.opts.SessionTTL,
Behavior: SessionBehaviorDelete,
}
id, _, err := session.Create(se, nil)
if err != nil {
return "", err
}
return id, nil
}
// contenderEntry returns a formatted KVPair for the contender
func (s *Semaphore) contenderEntry(session string) *KVPair {
return &KVPair{
Key: path.Join(s.opts.Prefix, session),
Value: s.opts.Value,
Session: session,
Flags: SemaphoreFlagValue,
}
}
// findLock is used to find the KV Pair which is used for coordination
func (s *Semaphore) findLock(pairs KVPairs) *KVPair {
key := path.Join(s.opts.Prefix, DefaultSemaphoreKey)
for _, pair := range pairs {
if pair.Key == key {
return pair
}
}
return &KVPair{Flags: SemaphoreFlagValue}
}
// decodeLock is used to decode a semaphoreLock from an
// entry in Consul
func (s *Semaphore) decodeLock(pair *KVPair) (*semaphoreLock, error) {
// Handle if there is no lock
if pair == nil || pair.Value == nil {
return &semaphoreLock{
Limit: s.opts.Limit,
Holders: make(map[string]bool),
}, nil
}
l := &semaphoreLock{}
if err := json.Unmarshal(pair.Value, l); err != nil {
return nil, fmt.Errorf("lock decoding failed: %v", err)
}
return l, nil
}
// encodeLock is used to encode a semaphoreLock into a KVPair
// that can be PUT
func (s *Semaphore) encodeLock(l *semaphoreLock, oldIndex uint64) (*KVPair, error) {
enc, err := json.Marshal(l)
if err != nil {
return nil, fmt.Errorf("lock encoding failed: %v", err)
}
pair := &KVPair{
Key: path.Join(s.opts.Prefix, DefaultSemaphoreKey),
Value: enc,
Flags: SemaphoreFlagValue,
ModifyIndex: oldIndex,
}
return pair, nil
}
// pruneDeadHolders is used to remove all the dead lock holders
func (s *Semaphore) pruneDeadHolders(lock *semaphoreLock, pairs KVPairs) {
// Gather all the live holders
alive := make(map[string]struct{}, len(pairs))
for _, pair := range pairs {
if pair.Session != "" {
alive[pair.Session] = struct{}{}
}
}
// Remove any holders that are dead
for holder := range lock.Holders {
if _, ok := alive[holder]; !ok {
delete(lock.Holders, holder)
}
}
}
// monitorLock is a long running routine to monitor a semaphore ownership
// It closes the stopCh if we lose our slot.
func (s *Semaphore) monitorLock(session string, stopCh chan struct{}) {
defer close(stopCh)
kv := s.c.KV()
opts := &QueryOptions{RequireConsistent: true}
WAIT:
pairs, meta, err := kv.List(s.opts.Prefix, opts)
if err != nil {
return
}
lockPair := s.findLock(pairs)
lock, err := s.decodeLock(lockPair)
if err != nil {
return
}
s.pruneDeadHolders(lock, pairs)
if _, ok := lock.Holders[session]; ok {
opts.WaitIndex = meta.LastIndex
goto WAIT
}
}

View File

@ -1,201 +0,0 @@
package api
import (
"fmt"
"time"
)
const (
// SessionBehaviorRelease is the default behavior and causes
// all associated locks to be released on session invalidation.
SessionBehaviorRelease = "release"
// SessionBehaviorDelete is new in Consul 0.5 and changes the
// behavior to delete all associated locks on session invalidation.
// It can be used in a way similar to Ephemeral Nodes in ZooKeeper.
SessionBehaviorDelete = "delete"
)
// SessionEntry represents a session in consul
type SessionEntry struct {
CreateIndex uint64
ID string
Name string
Node string
Checks []string
LockDelay time.Duration
Behavior string
TTL string
}
// Session can be used to query the Session endpoints
type Session struct {
c *Client
}
// Session returns a handle to the session endpoints
func (c *Client) Session() *Session {
return &Session{c}
}
// CreateNoChecks is like Create but is used specifically to create
// a session with no associated health checks.
func (s *Session) CreateNoChecks(se *SessionEntry, q *WriteOptions) (string, *WriteMeta, error) {
body := make(map[string]interface{})
body["Checks"] = []string{}
if se != nil {
if se.Name != "" {
body["Name"] = se.Name
}
if se.Node != "" {
body["Node"] = se.Node
}
if se.LockDelay != 0 {
body["LockDelay"] = durToMsec(se.LockDelay)
}
if se.Behavior != "" {
body["Behavior"] = se.Behavior
}
if se.TTL != "" {
body["TTL"] = se.TTL
}
}
return s.create(body, q)
}
// Create makes a new session. Providing a session entry can
// customize the session. It can also be nil to use defaults.
func (s *Session) Create(se *SessionEntry, q *WriteOptions) (string, *WriteMeta, error) {
var obj interface{}
if se != nil {
body := make(map[string]interface{})
obj = body
if se.Name != "" {
body["Name"] = se.Name
}
if se.Node != "" {
body["Node"] = se.Node
}
if se.LockDelay != 0 {
body["LockDelay"] = durToMsec(se.LockDelay)
}
if len(se.Checks) > 0 {
body["Checks"] = se.Checks
}
if se.Behavior != "" {
body["Behavior"] = se.Behavior
}
if se.TTL != "" {
body["TTL"] = se.TTL
}
}
return s.create(obj, q)
}
func (s *Session) create(obj interface{}, q *WriteOptions) (string, *WriteMeta, error) {
var out struct{ ID string }
wm, err := s.c.write("/v1/session/create", obj, &out, q)
if err != nil {
return "", nil, err
}
return out.ID, wm, nil
}
// Destroy invalides a given session
func (s *Session) Destroy(id string, q *WriteOptions) (*WriteMeta, error) {
wm, err := s.c.write("/v1/session/destroy/"+id, nil, nil, q)
if err != nil {
return nil, err
}
return wm, nil
}
// Renew renews the TTL on a given session
func (s *Session) Renew(id string, q *WriteOptions) (*SessionEntry, *WriteMeta, error) {
var entries []*SessionEntry
wm, err := s.c.write("/v1/session/renew/"+id, nil, &entries, q)
if err != nil {
return nil, nil, err
}
if len(entries) > 0 {
return entries[0], wm, nil
}
return nil, wm, nil
}
// RenewPeriodic is used to periodically invoke Session.Renew on a
// session until a doneCh is closed. This is meant to be used in a long running
// goroutine to ensure a session stays valid.
func (s *Session) RenewPeriodic(initialTTL string, id string, q *WriteOptions, doneCh chan struct{}) error {
ttl, err := time.ParseDuration(initialTTL)
if err != nil {
return err
}
waitDur := ttl / 2
lastRenewTime := time.Now()
var lastErr error
for {
if time.Since(lastRenewTime) > ttl {
return lastErr
}
select {
case <-time.After(waitDur):
entry, _, err := s.Renew(id, q)
if err != nil {
waitDur = time.Second
lastErr = err
continue
}
if entry == nil {
waitDur = time.Second
lastErr = fmt.Errorf("No SessionEntry returned")
continue
}
// Handle the server updating the TTL
ttl, _ = time.ParseDuration(entry.TTL)
waitDur = ttl / 2
lastRenewTime = time.Now()
case <-doneCh:
// Attempt a session destroy
s.Destroy(id, q)
return nil
}
}
}
// Info looks up a single session
func (s *Session) Info(id string, q *QueryOptions) (*SessionEntry, *QueryMeta, error) {
var entries []*SessionEntry
qm, err := s.c.query("/v1/session/info/"+id, &entries, q)
if err != nil {
return nil, nil, err
}
if len(entries) > 0 {
return entries[0], qm, nil
}
return nil, qm, nil
}
// List gets sessions for a node
func (s *Session) Node(node string, q *QueryOptions) ([]*SessionEntry, *QueryMeta, error) {
var entries []*SessionEntry
qm, err := s.c.query("/v1/session/node/"+node, &entries, q)
if err != nil {
return nil, nil, err
}
return entries, qm, nil
}
// List gets all active sessions
func (s *Session) List(q *QueryOptions) ([]*SessionEntry, *QueryMeta, error) {
var entries []*SessionEntry
qm, err := s.c.query("/v1/session/list", &entries, q)
if err != nil {
return nil, nil, err
}
return entries, qm, nil
}

View File

@ -1,43 +0,0 @@
package api
// Status can be used to query the Status endpoints
type Status struct {
c *Client
}
// Status returns a handle to the status endpoints
func (c *Client) Status() *Status {
return &Status{c}
}
// Leader is used to query for a known leader
func (s *Status) Leader() (string, error) {
r := s.c.newRequest("GET", "/v1/status/leader")
_, resp, err := requireOK(s.c.doRequest(r))
if err != nil {
return "", err
}
defer resp.Body.Close()
var leader string
if err := decodeBody(resp, &leader); err != nil {
return "", err
}
return leader, nil
}
// Peers is used to query for a known raft peers
func (s *Status) Peers() ([]string, error) {
r := s.c.newRequest("GET", "/v1/status/peers")
_, resp, err := requireOK(s.c.doRequest(r))
if err != nil {
return nil, err
}
defer resp.Body.Close()
var peers []string
if err := decodeBody(resp, &peers); err != nil {
return nil, err
}
return peers, nil
}