1
0
Fork 0
mirror of https://github.com/moby/moby.git synced 2022-11-09 12:21:53 -05:00
moby--moby/pkg/plugins/client.go
David Calavera 81fa9feb0c Volumes refactor and external plugin implementation.
Signed by all authors:

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
Signed-off-by: Arnaud Porterie <arnaud.porterie@docker.com>
Signed-off-by: David Calavera <david.calavera@gmail.com>
Signed-off-by: Jeff Lindsay <progrium@gmail.com>
Signed-off-by: Alexander Morozov <lk4d4@docker.com>
Signed-off-by: Luke Marsden <luke@clusterhq.com>
Signed-off-by: David Calavera <david.calavera@gmail.com>
2015-05-21 20:34:17 -07:00

112 lines
2.4 KiB
Go

package plugins
import (
"bytes"
"encoding/json"
"fmt"
"io/ioutil"
"net"
"net/http"
"strings"
"time"
"github.com/Sirupsen/logrus"
)
const (
versionMimetype = "application/vnd.docker.plugins.v1+json"
defaultTimeOut = 30
)
func NewClient(addr string) *Client {
tr := &http.Transport{}
protoAndAddr := strings.Split(addr, "://")
configureTCPTransport(tr, protoAndAddr[0], protoAndAddr[1])
return &Client{&http.Client{Transport: tr}, protoAndAddr[1]}
}
type Client struct {
http *http.Client
addr string
}
func (c *Client) Call(serviceMethod string, args interface{}, ret interface{}) error {
return c.callWithRetry(serviceMethod, args, ret, true)
}
func (c *Client) callWithRetry(serviceMethod string, args interface{}, ret interface{}, retry bool) error {
var buf bytes.Buffer
if err := json.NewEncoder(&buf).Encode(args); err != nil {
return err
}
req, err := http.NewRequest("POST", "/"+serviceMethod, &buf)
if err != nil {
return err
}
req.Header.Add("Accept", versionMimetype)
req.URL.Scheme = "http"
req.URL.Host = c.addr
var retries int
start := time.Now()
for {
resp, err := c.http.Do(req)
if err != nil {
if !retry {
return err
}
timeOff := backoff(retries)
if abort(start, timeOff) {
return err
}
retries++
logrus.Warnf("Unable to connect to plugin: %s, retrying in %v", c.addr, timeOff)
time.Sleep(timeOff)
continue
}
if resp.StatusCode != http.StatusOK {
remoteErr, err := ioutil.ReadAll(resp.Body)
if err != nil {
return nil
}
return fmt.Errorf("Plugin Error: %s", remoteErr)
}
return json.NewDecoder(resp.Body).Decode(&ret)
}
}
func backoff(retries int) time.Duration {
b, max := 1, defaultTimeOut
for b < max && retries > 0 {
b *= 2
retries--
}
if b > max {
b = max
}
return time.Duration(b) * time.Second
}
func abort(start time.Time, timeOff time.Duration) bool {
return timeOff+time.Since(start) > time.Duration(defaultTimeOut)*time.Second
}
func configureTCPTransport(tr *http.Transport, proto, addr string) {
// Why 32? See https://github.com/docker/docker/pull/8035.
timeout := 32 * time.Second
if proto == "unix" {
// No need for compression in local communications.
tr.DisableCompression = true
tr.Dial = func(_, _ string) (net.Conn, error) {
return net.DialTimeout(proto, addr, timeout)
}
} else {
tr.Proxy = http.ProxyFromEnvironment
tr.Dial = (&net.Dialer{Timeout: timeout}).Dial
}
}