[](https://travis-ci.org/Sirupsen/logrus) [](https://godoc.org/github.com/Sirupsen/logrus)
+
+Logrus is a structured logger for Go (golang), completely API compatible with
+the standard library logger. [Godoc][godoc]. **Please note the Logrus API is not
+yet stable (pre 1.0). Logrus itself is completely stable and has been used in
+many large deployments. The core API is unlikely to change much but please
+version control your Logrus to make sure you aren't fetching latest `master` on
+every build.**
+
+Nicely color-coded in development (when a TTY is attached, otherwise just
+plain text):
+
+
+
+With `log.SetFormatter(&log.JSONFormatter{})`, for easy parsing by logstash
+or Splunk:
+
+```json
+{"animal":"walrus","level":"info","msg":"A group of walrus emerges from the
+ocean","size":10,"time":"2014-03-10 19:57:38.562264131 -0400 EDT"}
+
+{"level":"warning","msg":"The group's number increased tremendously!",
+"number":122,"omg":true,"time":"2014-03-10 19:57:38.562471297 -0400 EDT"}
+
+{"animal":"walrus","level":"info","msg":"A giant walrus appears!",
+"size":10,"time":"2014-03-10 19:57:38.562500591 -0400 EDT"}
+
+{"animal":"walrus","level":"info","msg":"Tremendously sized cow enters the ocean.",
+"size":9,"time":"2014-03-10 19:57:38.562527896 -0400 EDT"}
+
+{"level":"fatal","msg":"The ice breaks!","number":100,"omg":true,
+"time":"2014-03-10 19:57:38.562543128 -0400 EDT"}
+```
+
+With the default `log.SetFormatter(&log.TextFormatter{})` when a TTY is not
+attached, the output is compatible with the
+[logfmt](http://godoc.org/github.com/kr/logfmt) format:
+
+```text
+time="2015-03-26T01:27:38-04:00" level=debug msg="Started observing beach" animal=walrus number=8
+time="2015-03-26T01:27:38-04:00" level=info msg="A group of walrus emerges from the ocean" animal=walrus size=10
+time="2015-03-26T01:27:38-04:00" level=warning msg="The group's number increased tremendously!" number=122 omg=true
+time="2015-03-26T01:27:38-04:00" level=debug msg="Temperature changes" temperature=-4
+time="2015-03-26T01:27:38-04:00" level=panic msg="It's over 9000!" animal=orca size=9009
+time="2015-03-26T01:27:38-04:00" level=fatal msg="The ice breaks!" err=&{0x2082280c0 map[animal:orca size:9009] 2015-03-26 01:27:38.441574009 -0400 EDT panic It's over 9000!} number=100 omg=true
+exit status 1
+```
+
+#### Example
+
+The simplest way to use Logrus is simply the package-level exported logger:
+
+```go
+package main
+
+import (
+ log "github.com/Sirupsen/logrus"
+)
+
+func main() {
+ log.WithFields(log.Fields{
+ "animal": "walrus",
+ }).Info("A walrus appears")
+}
+```
+
+Note that it's completely api-compatible with the stdlib logger, so you can
+replace your `log` imports everywhere with `log "github.com/Sirupsen/logrus"`
+and you'll now have the flexibility of Logrus. You can customize it all you
+want:
+
+```go
+package main
+
+import (
+ "os"
+ log "github.com/Sirupsen/logrus"
+)
+
+func init() {
+ // Log as JSON instead of the default ASCII formatter.
+ log.SetFormatter(&log.JSONFormatter{})
+
+ // Output to stderr instead of stdout, could also be a file.
+ log.SetOutput(os.Stderr)
+
+ // Only log the warning severity or above.
+ log.SetLevel(log.WarnLevel)
+}
+
+func main() {
+ log.WithFields(log.Fields{
+ "animal": "walrus",
+ "size": 10,
+ }).Info("A group of walrus emerges from the ocean")
+
+ log.WithFields(log.Fields{
+ "omg": true,
+ "number": 122,
+ }).Warn("The group's number increased tremendously!")
+
+ log.WithFields(log.Fields{
+ "omg": true,
+ "number": 100,
+ }).Fatal("The ice breaks!")
+
+ // A common pattern is to re-use fields between logging statements by re-using
+ // the logrus.Entry returned from WithFields()
+ contextLogger := log.WithFields(log.Fields{
+ "common": "this is a common field",
+ "other": "I also should be logged always",
+ })
+
+ contextLogger.Info("I'll be logged with common and other field")
+ contextLogger.Info("Me too")
+}
+```
+
+For more advanced usage such as logging to multiple locations from the same
+application, you can also create an instance of the `logrus` Logger:
+
+```go
+package main
+
+import (
+ "github.com/Sirupsen/logrus"
+)
+
+// Create a new instance of the logger. You can have any number of instances.
+var log = logrus.New()
+
+func main() {
+ // The API for setting attributes is a little different than the package level
+ // exported logger. See Godoc.
+ log.Out = os.Stderr
+
+ log.WithFields(logrus.Fields{
+ "animal": "walrus",
+ "size": 10,
+ }).Info("A group of walrus emerges from the ocean")
+}
+```
+
+#### Fields
+
+Logrus encourages careful, structured logging though logging fields instead of
+long, unparseable error messages. For example, instead of: `log.Fatalf("Failed
+to send event %s to topic %s with key %d")`, you should log the much more
+discoverable:
+
+```go
+log.WithFields(log.Fields{
+ "event": event,
+ "topic": topic,
+ "key": key,
+}).Fatal("Failed to send event")
+```
+
+We've found this API forces you to think about logging in a way that produces
+much more useful logging messages. We've been in countless situations where just
+a single added field to a log statement that was already there would've saved us
+hours. The `WithFields` call is optional.
+
+In general, with Logrus using any of the `printf`-family functions should be
+seen as a hint you should add a field, however, you can still use the
+`printf`-family functions with Logrus.
+
+#### Hooks
+
+You can add hooks for logging levels. For example to send errors to an exception
+tracking service on `Error`, `Fatal` and `Panic`, info to StatsD or log to
+multiple places simultaneously, e.g. syslog.
+
+Logrus comes with [built-in hooks](hooks/). Add those, or your custom hook, in
+`init`:
+
+```go
+import (
+ log "github.com/Sirupsen/logrus"
+ "gopkg.in/gemnasium/logrus-airbrake-hook.v2" // the package is named "aibrake"
+ logrus_syslog "github.com/Sirupsen/logrus/hooks/syslog"
+ "log/syslog"
+)
+
+func init() {
+
+ // Use the Airbrake hook to report errors that have Error severity or above to
+ // an exception tracker. You can create custom hooks, see the Hooks section.
+ log.AddHook(airbrake.NewHook(123, "xyz", "production"))
+
+ hook, err := logrus_syslog.NewSyslogHook("udp", "localhost:514", syslog.LOG_INFO, "")
+ if err != nil {
+ log.Error("Unable to connect to local syslog daemon")
+ } else {
+ log.AddHook(hook)
+ }
+}
+```
+Note: Syslog hook also support connecting to local syslog (Ex. "/dev/log" or "/var/run/syslog" or "/var/run/log"). For the detail, please check the [syslog hook README](hooks/syslog/README.md).
+
+| Hook | Description |
+| ----- | ----------- |
+| [Airbrake](https://github.com/gemnasium/logrus-airbrake-hook) | Send errors to the Airbrake API V3. Uses the official [`gobrake`](https://github.com/airbrake/gobrake) behind the scenes. |
+| [Airbrake "legacy"](https://github.com/gemnasium/logrus-airbrake-legacy-hook) | Send errors to an exception tracking service compatible with the Airbrake API V2. Uses [`airbrake-go`](https://github.com/tobi/airbrake-go) behind the scenes. |
+| [Papertrail](https://github.com/polds/logrus-papertrail-hook) | Send errors to the [Papertrail](https://papertrailapp.com) hosted logging service via UDP. |
+| [Syslog](https://github.com/Sirupsen/logrus/blob/master/hooks/syslog/syslog.go) | Send errors to remote syslog server. Uses standard library `log/syslog` behind the scenes. |
+| [Bugsnag](https://github.com/Shopify/logrus-bugsnag/blob/master/bugsnag.go) | Send errors to the Bugsnag exception tracking service. |
+| [Sentry](https://github.com/evalphobia/logrus_sentry) | Send errors to the Sentry error logging and aggregation service. |
+| [Hiprus](https://github.com/nubo/hiprus) | Send errors to a channel in hipchat. |
+| [Logrusly](https://github.com/sebest/logrusly) | Send logs to [Loggly](https://www.loggly.com/) |
+| [Slackrus](https://github.com/johntdyer/slackrus) | Hook for Slack chat. |
+| [Journalhook](https://github.com/wercker/journalhook) | Hook for logging to `systemd-journald` |
+| [Graylog](https://github.com/gemnasium/logrus-graylog-hook) | Hook for logging to [Graylog](http://graylog2.org/) |
+| [Raygun](https://github.com/squirkle/logrus-raygun-hook) | Hook for logging to [Raygun.io](http://raygun.io/) |
+| [LFShook](https://github.com/rifflock/lfshook) | Hook for logging to the local filesystem |
+| [Honeybadger](https://github.com/agonzalezro/logrus_honeybadger) | Hook for sending exceptions to Honeybadger |
+| [Mail](https://github.com/zbindenren/logrus_mail) | Hook for sending exceptions via mail |
+| [Rollrus](https://github.com/heroku/rollrus) | Hook for sending errors to rollbar |
+| [Fluentd](https://github.com/evalphobia/logrus_fluent) | Hook for logging to fluentd |
+| [Mongodb](https://github.com/weekface/mgorus) | Hook for logging to mongodb |
+| [InfluxDB](https://github.com/Abramovic/logrus_influxdb) | Hook for logging to influxdb |
+| [Octokit](https://github.com/dorajistyle/logrus-octokit-hook) | Hook for logging to github via octokit |
+| [DeferPanic](https://github.com/deferpanic/dp-logrus) | Hook for logging to DeferPanic |
+| [Redis-Hook](https://github.com/rogierlommers/logrus-redis-hook) | Hook for logging to a ELK stack (through Redis) |
+| [Amqp-Hook](https://github.com/vladoatanasov/logrus_amqp) | Hook for logging to Amqp broker (Like RabbitMQ) |
+| [KafkaLogrus](https://github.com/goibibo/KafkaLogrus) | Hook for logging to kafka |
+| [Typetalk](https://github.com/dragon3/logrus-typetalk-hook) | Hook for logging to [Typetalk](https://www.typetalk.in/) |
+| [ElasticSearch](https://github.com/sohlich/elogrus) | Hook for logging to ElasticSearch|
+
+
+#### Level logging
+
+Logrus has six logging levels: Debug, Info, Warning, Error, Fatal and Panic.
+
+```go
+log.Debug("Useful debugging information.")
+log.Info("Something noteworthy happened!")
+log.Warn("You should probably take a look at this.")
+log.Error("Something failed but I'm not quitting.")
+// Calls os.Exit(1) after logging
+log.Fatal("Bye.")
+// Calls panic() after logging
+log.Panic("I'm bailing.")
+```
+
+You can set the logging level on a `Logger`, then it will only log entries with
+that severity or anything above it:
+
+```go
+// Will log anything that is info or above (warn, error, fatal, panic). Default.
+log.SetLevel(log.InfoLevel)
+```
+
+It may be useful to set `log.Level = logrus.DebugLevel` in a debug or verbose
+environment if your application has that.
+
+#### Entries
+
+Besides the fields added with `WithField` or `WithFields` some fields are
+automatically added to all logging events:
+
+1. `time`. The timestamp when the entry was created.
+2. `msg`. The logging message passed to `{Info,Warn,Error,Fatal,Panic}` after
+ the `AddFields` call. E.g. `Failed to send event.`
+3. `level`. The logging level. E.g. `info`.
+
+#### Environments
+
+Logrus has no notion of environment.
+
+If you wish for hooks and formatters to only be used in specific environments,
+you should handle that yourself. For example, if your application has a global
+variable `Environment`, which is a string representation of the environment you
+could do:
+
+```go
+import (
+ log "github.com/Sirupsen/logrus"
+)
+
+init() {
+ // do something here to set environment depending on an environment variable
+ // or command-line flag
+ if Environment == "production" {
+ log.SetFormatter(&log.JSONFormatter{})
+ } else {
+ // The TextFormatter is default, you don't actually have to do this.
+ log.SetFormatter(&log.TextFormatter{})
+ }
+}
+```
+
+This configuration is how `logrus` was intended to be used, but JSON in
+production is mostly only useful if you do log aggregation with tools like
+Splunk or Logstash.
+
+#### Formatters
+
+The built-in logging formatters are:
+
+* `logrus.TextFormatter`. Logs the event in colors if stdout is a tty, otherwise
+ without colors.
+ * *Note:* to force colored output when there is no TTY, set the `ForceColors`
+ field to `true`. To force no colored output even if there is a TTY set the
+ `DisableColors` field to `true`
+* `logrus.JSONFormatter`. Logs fields as JSON.
+* `logrus/formatters/logstash.LogstashFormatter`. Logs fields as [Logstash](http://logstash.net) Events.
+
+ ```go
+ logrus.SetFormatter(&logstash.LogstashFormatter{Type: "application_name"})
+ ```
+
+Third party logging formatters:
+
+* [`prefixed`](https://github.com/x-cray/logrus-prefixed-formatter). Displays log entry source along with alternative layout.
+* [`zalgo`](https://github.com/aybabtme/logzalgo). Invoking the P͉̫o̳̼̊w̖͈̰͎e̬͔̭͂r͚̼̹̲ ̫͓͉̳͈ō̠͕͖̚f̝͍̠ ͕̲̞͖͑Z̖̫̤̫ͪa͉̬͈̗l͖͎g̳̥o̰̥̅!̣͔̲̻͊̄ ̙̘̦̹̦.
+
+You can define your formatter by implementing the `Formatter` interface,
+requiring a `Format` method. `Format` takes an `*Entry`. `entry.Data` is a
+`Fields` type (`map[string]interface{}`) with all your fields as well as the
+default ones (see Entries section above):
+
+```go
+type MyJSONFormatter struct {
+}
+
+log.SetFormatter(new(MyJSONFormatter))
+
+func (f *MyJSONFormatter) Format(entry *Entry) ([]byte, error) {
+ // Note this doesn't include Time, Level and Message which are available on
+ // the Entry. Consult `godoc` on information about those fields or read the
+ // source of the official loggers.
+ serialized, err := json.Marshal(entry.Data)
+ if err != nil {
+ return nil, fmt.Errorf("Failed to marshal fields to JSON, %v", err)
+ }
+ return append(serialized, '\n'), nil
+}
+```
+
+#### Logger as an `io.Writer`
+
+Logrus can be transformed into an `io.Writer`. That writer is the end of an `io.Pipe` and it is your responsibility to close it.
+
+```go
+w := logger.Writer()
+defer w.Close()
+
+srv := http.Server{
+ // create a stdlib log.Logger that writes to
+ // logrus.Logger.
+ ErrorLog: log.New(w, "", 0),
+}
+```
+
+Each line written to that writer will be printed the usual way, using formatters
+and hooks. The level for those entries is `info`.
+
+#### Rotation
+
+Log rotation is not provided with Logrus. Log rotation should be done by an
+external program (like `logrotate(8)`) that can compress and delete old log
+entries. It should not be a feature of the application-level logger.
+
+#### Tools
+
+| Tool | Description |
+| ---- | ----------- |
+|[Logrus Mate](https://github.com/gogap/logrus_mate)|Logrus mate is a tool for Logrus to manage loggers, you can initial logger's level, hook and formatter by config file, the logger will generated with different config at different environment.|
+
+#### Testing
+
+Logrus has a built in facility for asserting the presence of log messages. This is implemented through the `test` hook and provides:
+
+* decorators for existing logger (`test.NewLocal` and `test.NewGlobal`) which basically just add the `test` hook
+* a test logger (`test.NewNullLogger`) that just records log messages (and does not output any):
+
+```go
+logger, hook := NewNullLogger()
+logger.Error("Hello error")
+
+assert.Equal(1, len(hook.Entries))
+assert.Equal(logrus.ErrorLevel, hook.LastEntry().Level)
+assert.Equal("Hello error", hook.LastEntry().Message)
+
+hook.Reset()
+assert.Nil(hook.LastEntry())
+```
diff --git a/libnetwork/vendor/github.com/armon/go-metrics/README.md b/libnetwork/vendor/github.com/armon/go-metrics/README.md
new file mode 100644
index 0000000000..d9f46e85ba
--- /dev/null
+++ b/libnetwork/vendor/github.com/armon/go-metrics/README.md
@@ -0,0 +1,68 @@
+go-metrics
+==========
+
+This library provides a `metrics` package which can be used to instrument code,
+expose application metrics, and profile runtime performance in a flexible manner.
+
+Sinks
+=====
+
+The `metrics` package makes use of a `MetricSink` interface to support delivery
+to any type of backend. Currently the following sinks are provided:
+
+* StatsiteSink : Sinks to a statsite instance (TCP)
+* StatsdSink: Sinks to a statsd / statsite instance (UDP)
+* InmemSink : Provides in-memory aggregation, can be used to export stats
+* FanoutSink : Sinks to multiple sinks. Enables writing to multiple statsite instances for example.
+* BlackholeSink : Sinks to nowhere
+
+In addition to the sinks, the `InmemSignal` can be used to catch a signal,
+and dump a formatted output of recent metrics. For example, when a process gets
+a SIGUSR1, it can dump to stderr recent performance metrics for debugging.
+
+Examples
+========
+
+Here is an example of using the package:
+
+ func SlowMethod() {
+ // Profiling the runtime of a method
+ defer metrics.MeasureSince([]string{"SlowMethod"}, time.Now())
+ }
+
+ // Configure a statsite sink as the global metrics sink
+ sink, _ := metrics.NewStatsiteSink("statsite:8125")
+ metrics.NewGlobal(metrics.DefaultConfig("service-name"), sink)
+
+ // Emit a Key/Value pair
+ metrics.EmitKey([]string{"questions", "meaning of life"}, 42)
+
+
+Here is an example of setting up an signal handler:
+
+ // Setup the inmem sink and signal handler
+ inm := NewInmemSink(10*time.Second, time.Minute)
+ sig := DefaultInmemSignal(inm)
+ metrics.NewGlobal(metrics.DefaultConfig("service-name"), inm)
+
+ // Run some code
+ inm.SetGauge([]string{"foo"}, 42)
+ inm.EmitKey([]string{"bar"}, 30)
+
+ inm.IncrCounter([]string{"baz"}, 42)
+ inm.IncrCounter([]string{"baz"}, 1)
+ inm.IncrCounter([]string{"baz"}, 80)
+
+ inm.AddSample([]string{"method", "wow"}, 42)
+ inm.AddSample([]string{"method", "wow"}, 100)
+ inm.AddSample([]string{"method", "wow"}, 22)
+
+ ....
+
+When a signal comes in, output like the following will be dumped to stderr:
+
+ [2014-01-28 14:57:33.04 -0800 PST][G] 'foo': 42.000
+ [2014-01-28 14:57:33.04 -0800 PST][P] 'bar': 30.000
+ [2014-01-28 14:57:33.04 -0800 PST][C] 'baz': Count: 3 Min: 1.000 Mean: 41.000 Max: 80.000 Stddev: 39.509
+ [2014-01-28 14:57:33.04 -0800 PST][S] 'method.wow': Count: 3 Min: 22.000 Mean: 54.667 Max: 100.000 Stddev: 40.513
+
diff --git a/libnetwork/vendor/github.com/armon/go-radix/README.md b/libnetwork/vendor/github.com/armon/go-radix/README.md
new file mode 100644
index 0000000000..c054fe86c0
--- /dev/null
+++ b/libnetwork/vendor/github.com/armon/go-radix/README.md
@@ -0,0 +1,36 @@
+go-radix [](https://travis-ci.org/armon/go-radix)
+=========
+
+Provides the `radix` package that implements a [radix tree](http://en.wikipedia.org/wiki/Radix_tree).
+The package only provides a single `Tree` implementation, optimized for sparse nodes.
+
+As a radix tree, it provides the following:
+ * O(k) operations. In many cases, this can be faster than a hash table since
+ the hash function is an O(k) operation, and hash tables have very poor cache locality.
+ * Minimum / Maximum value lookups
+ * Ordered iteration
+
+Documentation
+=============
+
+The full documentation is available on [Godoc](http://godoc.org/github.com/armon/go-radix).
+
+Example
+=======
+
+Below is a simple example of usage
+
+```go
+// Create a tree
+r := radix.New()
+r.Insert("foo", 1)
+r.Insert("bar", 2)
+r.Insert("foobar", 2)
+
+// Find the longest prefix match
+m, _, _ := r.LongestPrefix("foozip")
+if m != "foo" {
+ panic("should be foo")
+}
+```
+
diff --git a/libnetwork/vendor/github.com/boltdb/bolt/README.md b/libnetwork/vendor/github.com/boltdb/bolt/README.md
new file mode 100644
index 0000000000..66b19ace8a
--- /dev/null
+++ b/libnetwork/vendor/github.com/boltdb/bolt/README.md
@@ -0,0 +1,844 @@
+Bolt [](https://drone.io/github.com/boltdb/bolt/latest) [](https://coveralls.io/r/boltdb/bolt?branch=master) [](https://godoc.org/github.com/boltdb/bolt) 
+====
+
+Bolt is a pure Go key/value store inspired by [Howard Chu's][hyc_symas]
+[LMDB project][lmdb]. The goal of the project is to provide a simple,
+fast, and reliable database for projects that don't require a full database
+server such as Postgres or MySQL.
+
+Since Bolt is meant to be used as such a low-level piece of functionality,
+simplicity is key. The API will be small and only focus on getting values
+and setting values. That's it.
+
+[hyc_symas]: https://twitter.com/hyc_symas
+[lmdb]: http://symas.com/mdb/
+
+## Project Status
+
+Bolt is stable and the API is fixed. Full unit test coverage and randomized
+black box testing are used to ensure database consistency and thread safety.
+Bolt is currently in high-load production environments serving databases as
+large as 1TB. Many companies such as Shopify and Heroku use Bolt-backed
+services every day.
+
+## Table of Contents
+
+- [Getting Started](#getting-started)
+ - [Installing](#installing)
+ - [Opening a database](#opening-a-database)
+ - [Transactions](#transactions)
+ - [Read-write transactions](#read-write-transactions)
+ - [Read-only transactions](#read-only-transactions)
+ - [Batch read-write transactions](#batch-read-write-transactions)
+ - [Managing transactions manually](#managing-transactions-manually)
+ - [Using buckets](#using-buckets)
+ - [Using key/value pairs](#using-keyvalue-pairs)
+ - [Autoincrementing integer for the bucket](#autoincrementing-integer-for-the-bucket)
+ - [Iterating over keys](#iterating-over-keys)
+ - [Prefix scans](#prefix-scans)
+ - [Range scans](#range-scans)
+ - [ForEach()](#foreach)
+ - [Nested buckets](#nested-buckets)
+ - [Database backups](#database-backups)
+ - [Statistics](#statistics)
+ - [Read-Only Mode](#read-only-mode)
+ - [Mobile Use (iOS/Android)](#mobile-use-iosandroid)
+- [Resources](#resources)
+- [Comparison with other databases](#comparison-with-other-databases)
+ - [Postgres, MySQL, & other relational databases](#postgres-mysql--other-relational-databases)
+ - [LevelDB, RocksDB](#leveldb-rocksdb)
+ - [LMDB](#lmdb)
+- [Caveats & Limitations](#caveats--limitations)
+- [Reading the Source](#reading-the-source)
+- [Other Projects Using Bolt](#other-projects-using-bolt)
+
+## Getting Started
+
+### Installing
+
+To start using Bolt, install Go and run `go get`:
+
+```sh
+$ go get github.com/boltdb/bolt/...
+```
+
+This will retrieve the library and install the `bolt` command line utility into
+your `$GOBIN` path.
+
+
+### Opening a database
+
+The top-level object in Bolt is a `DB`. It is represented as a single file on
+your disk and represents a consistent snapshot of your data.
+
+To open your database, simply use the `bolt.Open()` function:
+
+```go
+package main
+
+import (
+ "log"
+
+ "github.com/boltdb/bolt"
+)
+
+func main() {
+ // Open the my.db data file in your current directory.
+ // It will be created if it doesn't exist.
+ db, err := bolt.Open("my.db", 0600, nil)
+ if err != nil {
+ log.Fatal(err)
+ }
+ defer db.Close()
+
+ ...
+}
+```
+
+Please note that Bolt obtains a file lock on the data file so multiple processes
+cannot open the same database at the same time. Opening an already open Bolt
+database will cause it to hang until the other process closes it. To prevent
+an indefinite wait you can pass a timeout option to the `Open()` function:
+
+```go
+db, err := bolt.Open("my.db", 0600, &bolt.Options{Timeout: 1 * time.Second})
+```
+
+
+### Transactions
+
+Bolt allows only one read-write transaction at a time but allows as many
+read-only transactions as you want at a time. Each transaction has a consistent
+view of the data as it existed when the transaction started.
+
+Individual transactions and all objects created from them (e.g. buckets, keys)
+are not thread safe. To work with data in multiple goroutines you must start
+a transaction for each one or use locking to ensure only one goroutine accesses
+a transaction at a time. Creating transaction from the `DB` is thread safe.
+
+Read-only transactions and read-write transactions should not depend on one
+another and generally shouldn't be opened simultaneously in the same goroutine.
+This can cause a deadlock as the read-write transaction needs to periodically
+re-map the data file but it cannot do so while a read-only transaction is open.
+
+
+#### Read-write transactions
+
+To start a read-write transaction, you can use the `DB.Update()` function:
+
+```go
+err := db.Update(func(tx *bolt.Tx) error {
+ ...
+ return nil
+})
+```
+
+Inside the closure, you have a consistent view of the database. You commit the
+transaction by returning `nil` at the end. You can also rollback the transaction
+at any point by returning an error. All database operations are allowed inside
+a read-write transaction.
+
+Always check the return error as it will report any disk failures that can cause
+your transaction to not complete. If you return an error within your closure
+it will be passed through.
+
+
+#### Read-only transactions
+
+To start a read-only transaction, you can use the `DB.View()` function:
+
+```go
+err := db.View(func(tx *bolt.Tx) error {
+ ...
+ return nil
+})
+```
+
+You also get a consistent view of the database within this closure, however,
+no mutating operations are allowed within a read-only transaction. You can only
+retrieve buckets, retrieve values, and copy the database within a read-only
+transaction.
+
+
+#### Batch read-write transactions
+
+Each `DB.Update()` waits for disk to commit the writes. This overhead
+can be minimized by combining multiple updates with the `DB.Batch()`
+function:
+
+```go
+err := db.Batch(func(tx *bolt.Tx) error {
+ ...
+ return nil
+})
+```
+
+Concurrent Batch calls are opportunistically combined into larger
+transactions. Batch is only useful when there are multiple goroutines
+calling it.
+
+The trade-off is that `Batch` can call the given
+function multiple times, if parts of the transaction fail. The
+function must be idempotent and side effects must take effect only
+after a successful return from `DB.Batch()`.
+
+For example: don't display messages from inside the function, instead
+set variables in the enclosing scope:
+
+```go
+var id uint64
+err := db.Batch(func(tx *bolt.Tx) error {
+ // Find last key in bucket, decode as bigendian uint64, increment
+ // by one, encode back to []byte, and add new key.
+ ...
+ id = newValue
+ return nil
+})
+if err != nil {
+ return ...
+}
+fmt.Println("Allocated ID %d", id)
+```
+
+
+#### Managing transactions manually
+
+The `DB.View()` and `DB.Update()` functions are wrappers around the `DB.Begin()`
+function. These helper functions will start the transaction, execute a function,
+and then safely close your transaction if an error is returned. This is the
+recommended way to use Bolt transactions.
+
+However, sometimes you may want to manually start and end your transactions.
+You can use the `Tx.Begin()` function directly but **please** be sure to close
+the transaction.
+
+```go
+// Start a writable transaction.
+tx, err := db.Begin(true)
+if err != nil {
+ return err
+}
+defer tx.Rollback()
+
+// Use the transaction...
+_, err := tx.CreateBucket([]byte("MyBucket"))
+if err != nil {
+ return err
+}
+
+// Commit the transaction and check for error.
+if err := tx.Commit(); err != nil {
+ return err
+}
+```
+
+The first argument to `DB.Begin()` is a boolean stating if the transaction
+should be writable.
+
+
+### Using buckets
+
+Buckets are collections of key/value pairs within the database. All keys in a
+bucket must be unique. You can create a bucket using the `DB.CreateBucket()`
+function:
+
+```go
+db.Update(func(tx *bolt.Tx) error {
+ b, err := tx.CreateBucket([]byte("MyBucket"))
+ if err != nil {
+ return fmt.Errorf("create bucket: %s", err)
+ }
+ return nil
+})
+```
+
+You can also create a bucket only if it doesn't exist by using the
+`Tx.CreateBucketIfNotExists()` function. It's a common pattern to call this
+function for all your top-level buckets after you open your database so you can
+guarantee that they exist for future transactions.
+
+To delete a bucket, simply call the `Tx.DeleteBucket()` function.
+
+
+### Using key/value pairs
+
+To save a key/value pair to a bucket, use the `Bucket.Put()` function:
+
+```go
+db.Update(func(tx *bolt.Tx) error {
+ b := tx.Bucket([]byte("MyBucket"))
+ err := b.Put([]byte("answer"), []byte("42"))
+ return err
+})
+```
+
+This will set the value of the `"answer"` key to `"42"` in the `MyBucket`
+bucket. To retrieve this value, we can use the `Bucket.Get()` function:
+
+```go
+db.View(func(tx *bolt.Tx) error {
+ b := tx.Bucket([]byte("MyBucket"))
+ v := b.Get([]byte("answer"))
+ fmt.Printf("The answer is: %s\n", v)
+ return nil
+})
+```
+
+The `Get()` function does not return an error because its operation is
+guaranteed to work (unless there is some kind of system failure). If the key
+exists then it will return its byte slice value. If it doesn't exist then it
+will return `nil`. It's important to note that you can have a zero-length value
+set to a key which is different than the key not existing.
+
+Use the `Bucket.Delete()` function to delete a key from the bucket.
+
+Please note that values returned from `Get()` are only valid while the
+transaction is open. If you need to use a value outside of the transaction
+then you must use `copy()` to copy it to another byte slice.
+
+
+### Autoincrementing integer for the bucket
+By using the `NextSequence()` function, you can let Bolt determine a sequence
+which can be used as the unique identifier for your key/value pairs. See the
+example below.
+
+```go
+// CreateUser saves u to the store. The new user ID is set on u once the data is persisted.
+func (s *Store) CreateUser(u *User) error {
+ return s.db.Update(func(tx *bolt.Tx) error {
+ // Retrieve the users bucket.
+ // This should be created when the DB is first opened.
+ b := tx.Bucket([]byte("users"))
+
+ // Generate ID for the user.
+ // This returns an error only if the Tx is closed or not writeable.
+ // That can't happen in an Update() call so I ignore the error check.
+ id, _ = b.NextSequence()
+ u.ID = int(id)
+
+ // Marshal user data into bytes.
+ buf, err := json.Marshal(u)
+ if err != nil {
+ return err
+ }
+
+ // Persist bytes to users bucket.
+ return b.Put(itob(u.ID), buf)
+ })
+}
+
+// itob returns an 8-byte big endian representation of v.
+func itob(v int) []byte {
+ b := make([]byte, 8)
+ binary.BigEndian.PutUint64(b, uint64(v))
+ return b
+}
+
+type User struct {
+ ID int
+ ...
+}
+```
+
+### Iterating over keys
+
+Bolt stores its keys in byte-sorted order within a bucket. This makes sequential
+iteration over these keys extremely fast. To iterate over keys we'll use a
+`Cursor`:
+
+```go
+db.View(func(tx *bolt.Tx) error {
+ // Assume bucket exists and has keys
+ b := tx.Bucket([]byte("MyBucket"))
+
+ c := b.Cursor()
+
+ for k, v := c.First(); k != nil; k, v = c.Next() {
+ fmt.Printf("key=%s, value=%s\n", k, v)
+ }
+
+ return nil
+})
+```
+
+The cursor allows you to move to a specific point in the list of keys and move
+forward or backward through the keys one at a time.
+
+The following functions are available on the cursor:
+
+```
+First() Move to the first key.
+Last() Move to the last key.
+Seek() Move to a specific key.
+Next() Move to the next key.
+Prev() Move to the previous key.
+```
+
+Each of those functions has a return signature of `(key []byte, value []byte)`.
+When you have iterated to the end of the cursor then `Next()` will return a
+`nil` key. You must seek to a position using `First()`, `Last()`, or `Seek()`
+before calling `Next()` or `Prev()`. If you do not seek to a position then
+these functions will return a `nil` key.
+
+During iteration, if the key is non-`nil` but the value is `nil`, that means
+the key refers to a bucket rather than a value. Use `Bucket.Bucket()` to
+access the sub-bucket.
+
+
+#### Prefix scans
+
+To iterate over a key prefix, you can combine `Seek()` and `bytes.HasPrefix()`:
+
+```go
+db.View(func(tx *bolt.Tx) error {
+ // Assume bucket exists and has keys
+ c := tx.Bucket([]byte("MyBucket")).Cursor()
+
+ prefix := []byte("1234")
+ for k, v := c.Seek(prefix); bytes.HasPrefix(k, prefix); k, v = c.Next() {
+ fmt.Printf("key=%s, value=%s\n", k, v)
+ }
+
+ return nil
+})
+```
+
+#### Range scans
+
+Another common use case is scanning over a range such as a time range. If you
+use a sortable time encoding such as RFC3339 then you can query a specific
+date range like this:
+
+```go
+db.View(func(tx *bolt.Tx) error {
+ // Assume our events bucket exists and has RFC3339 encoded time keys.
+ c := tx.Bucket([]byte("Events")).Cursor()
+
+ // Our time range spans the 90's decade.
+ min := []byte("1990-01-01T00:00:00Z")
+ max := []byte("2000-01-01T00:00:00Z")
+
+ // Iterate over the 90's.
+ for k, v := c.Seek(min); k != nil && bytes.Compare(k, max) <= 0; k, v = c.Next() {
+ fmt.Printf("%s: %s\n", k, v)
+ }
+
+ return nil
+})
+```
+
+
+#### ForEach()
+
+You can also use the function `ForEach()` if you know you'll be iterating over
+all the keys in a bucket:
+
+```go
+db.View(func(tx *bolt.Tx) error {
+ // Assume bucket exists and has keys
+ b := tx.Bucket([]byte("MyBucket"))
+
+ b.ForEach(func(k, v []byte) error {
+ fmt.Printf("key=%s, value=%s\n", k, v)
+ return nil
+ })
+ return nil
+})
+```
+
+
+### Nested buckets
+
+You can also store a bucket in a key to create nested buckets. The API is the
+same as the bucket management API on the `DB` object:
+
+```go
+func (*Bucket) CreateBucket(key []byte) (*Bucket, error)
+func (*Bucket) CreateBucketIfNotExists(key []byte) (*Bucket, error)
+func (*Bucket) DeleteBucket(key []byte) error
+```
+
+
+### Database backups
+
+Bolt is a single file so it's easy to backup. You can use the `Tx.WriteTo()`
+function to write a consistent view of the database to a writer. If you call
+this from a read-only transaction, it will perform a hot backup and not block
+your other database reads and writes.
+
+By default, it will use a regular file handle which will utilize the operating
+system's page cache. See the [`Tx`](https://godoc.org/github.com/boltdb/bolt#Tx)
+documentation for information about optimizing for larger-than-RAM datasets.
+
+One common use case is to backup over HTTP so you can use tools like `cURL` to
+do database backups:
+
+```go
+func BackupHandleFunc(w http.ResponseWriter, req *http.Request) {
+ err := db.View(func(tx *bolt.Tx) error {
+ w.Header().Set("Content-Type", "application/octet-stream")
+ w.Header().Set("Content-Disposition", `attachment; filename="my.db"`)
+ w.Header().Set("Content-Length", strconv.Itoa(int(tx.Size())))
+ _, err := tx.WriteTo(w)
+ return err
+ })
+ if err != nil {
+ http.Error(w, err.Error(), http.StatusInternalServerError)
+ }
+}
+```
+
+Then you can backup using this command:
+
+```sh
+$ curl http://localhost/backup > my.db
+```
+
+Or you can open your browser to `http://localhost/backup` and it will download
+automatically.
+
+If you want to backup to another file you can use the `Tx.CopyFile()` helper
+function.
+
+
+### Statistics
+
+The database keeps a running count of many of the internal operations it
+performs so you can better understand what's going on. By grabbing a snapshot
+of these stats at two points in time we can see what operations were performed
+in that time range.
+
+For example, we could start a goroutine to log stats every 10 seconds:
+
+```go
+go func() {
+ // Grab the initial stats.
+ prev := db.Stats()
+
+ for {
+ // Wait for 10s.
+ time.Sleep(10 * time.Second)
+
+ // Grab the current stats and diff them.
+ stats := db.Stats()
+ diff := stats.Sub(&prev)
+
+ // Encode stats to JSON and print to STDERR.
+ json.NewEncoder(os.Stderr).Encode(diff)
+
+ // Save stats for the next loop.
+ prev = stats
+ }
+}()
+```
+
+It's also useful to pipe these stats to a service such as statsd for monitoring
+or to provide an HTTP endpoint that will perform a fixed-length sample.
+
+
+### Read-Only Mode
+
+Sometimes it is useful to create a shared, read-only Bolt database. To this,
+set the `Options.ReadOnly` flag when opening your database. Read-only mode
+uses a shared lock to allow multiple processes to read from the database but
+it will block any processes from opening the database in read-write mode.
+
+```go
+db, err := bolt.Open("my.db", 0666, &bolt.Options{ReadOnly: true})
+if err != nil {
+ log.Fatal(err)
+}
+```
+
+### Mobile Use (iOS/Android)
+
+Bolt is able to run on mobile devices by leveraging the binding feature of the
+[gomobile](https://github.com/golang/mobile) tool. Create a struct that will
+contain your database logic and a reference to a `*bolt.DB` with a initializing
+contstructor that takes in a filepath where the database file will be stored.
+Neither Android nor iOS require extra permissions or cleanup from using this method.
+
+```go
+func NewBoltDB(filepath string) *BoltDB {
+ db, err := bolt.Open(filepath+"/demo.db", 0600, nil)
+ if err != nil {
+ log.Fatal(err)
+ }
+
+ return &BoltDB{db}
+}
+
+type BoltDB struct {
+ db *bolt.DB
+ ...
+}
+
+func (b *BoltDB) Path() string {
+ return b.db.Path()
+}
+
+func (b *BoltDB) Close() {
+ b.db.Close()
+}
+```
+
+Database logic should be defined as methods on this wrapper struct.
+
+To initialize this struct from the native language (both platforms now sync
+their local storage to the cloud. These snippets disable that functionality for the
+database file):
+
+#### Android
+
+```java
+String path;
+if (android.os.Build.VERSION.SDK_INT >=android.os.Build.VERSION_CODES.LOLLIPOP){
+ path = getNoBackupFilesDir().getAbsolutePath();
+} else{
+ path = getFilesDir().getAbsolutePath();
+}
+Boltmobiledemo.BoltDB boltDB = Boltmobiledemo.NewBoltDB(path)
+```
+
+#### iOS
+
+```objc
+- (void)demo {
+ NSString* path = [NSSearchPathForDirectoriesInDomains(NSLibraryDirectory,
+ NSUserDomainMask,
+ YES) objectAtIndex:0];
+ GoBoltmobiledemoBoltDB * demo = GoBoltmobiledemoNewBoltDB(path);
+ [self addSkipBackupAttributeToItemAtPath:demo.path];
+ //Some DB Logic would go here
+ [demo close];
+}
+
+- (BOOL)addSkipBackupAttributeToItemAtPath:(NSString *) filePathString
+{
+ NSURL* URL= [NSURL fileURLWithPath: filePathString];
+ assert([[NSFileManager defaultManager] fileExistsAtPath: [URL path]]);
+
+ NSError *error = nil;
+ BOOL success = [URL setResourceValue: [NSNumber numberWithBool: YES]
+ forKey: NSURLIsExcludedFromBackupKey error: &error];
+ if(!success){
+ NSLog(@"Error excluding %@ from backup %@", [URL lastPathComponent], error);
+ }
+ return success;
+}
+
+```
+
+## Resources
+
+For more information on getting started with Bolt, check out the following articles:
+
+* [Intro to BoltDB: Painless Performant Persistence](http://npf.io/2014/07/intro-to-boltdb-painless-performant-persistence/) by [Nate Finch](https://github.com/natefinch).
+* [Bolt -- an embedded key/value database for Go](https://www.progville.com/go/bolt-embedded-db-golang/) by Progville
+
+
+## Comparison with other databases
+
+### Postgres, MySQL, & other relational databases
+
+Relational databases structure data into rows and are only accessible through
+the use of SQL. This approach provides flexibility in how you store and query
+your data but also incurs overhead in parsing and planning SQL statements. Bolt
+accesses all data by a byte slice key. This makes Bolt fast to read and write
+data by key but provides no built-in support for joining values together.
+
+Most relational databases (with the exception of SQLite) are standalone servers
+that run separately from your application. This gives your systems
+flexibility to connect multiple application servers to a single database
+server but also adds overhead in serializing and transporting data over the
+network. Bolt runs as a library included in your application so all data access
+has to go through your application's process. This brings data closer to your
+application but limits multi-process access to the data.
+
+
+### LevelDB, RocksDB
+
+LevelDB and its derivatives (RocksDB, HyperLevelDB) are similar to Bolt in that
+they are libraries bundled into the application, however, their underlying
+structure is a log-structured merge-tree (LSM tree). An LSM tree optimizes
+random writes by using a write ahead log and multi-tiered, sorted files called
+SSTables. Bolt uses a B+tree internally and only a single file. Both approaches
+have trade-offs.
+
+If you require a high random write throughput (>10,000 w/sec) or you need to use
+spinning disks then LevelDB could be a good choice. If your application is
+read-heavy or does a lot of range scans then Bolt could be a good choice.
+
+One other important consideration is that LevelDB does not have transactions.
+It supports batch writing of key/values pairs and it supports read snapshots
+but it will not give you the ability to do a compare-and-swap operation safely.
+Bolt supports fully serializable ACID transactions.
+
+
+### LMDB
+
+Bolt was originally a port of LMDB so it is architecturally similar. Both use
+a B+tree, have ACID semantics with fully serializable transactions, and support
+lock-free MVCC using a single writer and multiple readers.
+
+The two projects have somewhat diverged. LMDB heavily focuses on raw performance
+while Bolt has focused on simplicity and ease of use. For example, LMDB allows
+several unsafe actions such as direct writes for the sake of performance. Bolt
+opts to disallow actions which can leave the database in a corrupted state. The
+only exception to this in Bolt is `DB.NoSync`.
+
+There are also a few differences in API. LMDB requires a maximum mmap size when
+opening an `mdb_env` whereas Bolt will handle incremental mmap resizing
+automatically. LMDB overloads the getter and setter functions with multiple
+flags whereas Bolt splits these specialized cases into their own functions.
+
+
+## Caveats & Limitations
+
+It's important to pick the right tool for the job and Bolt is no exception.
+Here are a few things to note when evaluating and using Bolt:
+
+* Bolt is good for read intensive workloads. Sequential write performance is
+ also fast but random writes can be slow. You can use `DB.Batch()` or add a
+ write-ahead log to help mitigate this issue.
+
+* Bolt uses a B+tree internally so there can be a lot of random page access.
+ SSDs provide a significant performance boost over spinning disks.
+
+* Try to avoid long running read transactions. Bolt uses copy-on-write so
+ old pages cannot be reclaimed while an old transaction is using them.
+
+* Byte slices returned from Bolt are only valid during a transaction. Once the
+ transaction has been committed or rolled back then the memory they point to
+ can be reused by a new page or can be unmapped from virtual memory and you'll
+ see an `unexpected fault address` panic when accessing it.
+
+* Be careful when using `Bucket.FillPercent`. Setting a high fill percent for
+ buckets that have random inserts will cause your database to have very poor
+ page utilization.
+
+* Use larger buckets in general. Smaller buckets causes poor page utilization
+ once they become larger than the page size (typically 4KB).
+
+* Bulk loading a lot of random writes into a new bucket can be slow as the
+ page will not split until the transaction is committed. Randomly inserting
+ more than 100,000 key/value pairs into a single new bucket in a single
+ transaction is not advised.
+
+* Bolt uses a memory-mapped file so the underlying operating system handles the
+ caching of the data. Typically, the OS will cache as much of the file as it
+ can in memory and will release memory as needed to other processes. This means
+ that Bolt can show very high memory usage when working with large databases.
+ However, this is expected and the OS will release memory as needed. Bolt can
+ handle databases much larger than the available physical RAM, provided its
+ memory-map fits in the process virtual address space. It may be problematic
+ on 32-bits systems.
+
+* The data structures in the Bolt database are memory mapped so the data file
+ will be endian specific. This means that you cannot copy a Bolt file from a
+ little endian machine to a big endian machine and have it work. For most
+ users this is not a concern since most modern CPUs are little endian.
+
+* Because of the way pages are laid out on disk, Bolt cannot truncate data files
+ and return free pages back to the disk. Instead, Bolt maintains a free list
+ of unused pages within its data file. These free pages can be reused by later
+ transactions. This works well for many use cases as databases generally tend
+ to grow. However, it's important to note that deleting large chunks of data
+ will not allow you to reclaim that space on disk.
+
+ For more information on page allocation, [see this comment][page-allocation].
+
+[page-allocation]: https://github.com/boltdb/bolt/issues/308#issuecomment-74811638
+
+
+## Reading the Source
+
+Bolt is a relatively small code base (<3KLOC) for an embedded, serializable,
+transactional key/value database so it can be a good starting point for people
+interested in how databases work.
+
+The best places to start are the main entry points into Bolt:
+
+- `Open()` - Initializes the reference to the database. It's responsible for
+ creating the database if it doesn't exist, obtaining an exclusive lock on the
+ file, reading the meta pages, & memory-mapping the file.
+
+- `DB.Begin()` - Starts a read-only or read-write transaction depending on the
+ value of the `writable` argument. This requires briefly obtaining the "meta"
+ lock to keep track of open transactions. Only one read-write transaction can
+ exist at a time so the "rwlock" is acquired during the life of a read-write
+ transaction.
+
+- `Bucket.Put()` - Writes a key/value pair into a bucket. After validating the
+ arguments, a cursor is used to traverse the B+tree to the page and position
+ where they key & value will be written. Once the position is found, the bucket
+ materializes the underlying page and the page's parent pages into memory as
+ "nodes". These nodes are where mutations occur during read-write transactions.
+ These changes get flushed to disk during commit.
+
+- `Bucket.Get()` - Retrieves a key/value pair from a bucket. This uses a cursor
+ to move to the page & position of a key/value pair. During a read-only
+ transaction, the key and value data is returned as a direct reference to the
+ underlying mmap file so there's no allocation overhead. For read-write
+ transactions, this data may reference the mmap file or one of the in-memory
+ node values.
+
+- `Cursor` - This object is simply for traversing the B+tree of on-disk pages
+ or in-memory nodes. It can seek to a specific key, move to the first or last
+ value, or it can move forward or backward. The cursor handles the movement up
+ and down the B+tree transparently to the end user.
+
+- `Tx.Commit()` - Converts the in-memory dirty nodes and the list of free pages
+ into pages to be written to disk. Writing to disk then occurs in two phases.
+ First, the dirty pages are written to disk and an `fsync()` occurs. Second, a
+ new meta page with an incremented transaction ID is written and another
+ `fsync()` occurs. This two phase write ensures that partially written data
+ pages are ignored in the event of a crash since the meta page pointing to them
+ is never written. Partially written meta pages are invalidated because they
+ are written with a checksum.
+
+If you have additional notes that could be helpful for others, please submit
+them via pull request.
+
+
+## Other Projects Using Bolt
+
+Below is a list of public, open source projects that use Bolt:
+
+* [Operation Go: A Routine Mission](http://gocode.io) - An online programming game for Golang using Bolt for user accounts and a leaderboard.
+* [Bazil](https://bazil.org/) - A file system that lets your data reside where it is most convenient for it to reside.
+* [DVID](https://github.com/janelia-flyem/dvid) - Added Bolt as optional storage engine and testing it against Basho-tuned leveldb.
+* [Skybox Analytics](https://github.com/skybox/skybox) - A standalone funnel analysis tool for web analytics.
+* [Scuttlebutt](https://github.com/benbjohnson/scuttlebutt) - Uses Bolt to store and process all Twitter mentions of GitHub projects.
+* [Wiki](https://github.com/peterhellberg/wiki) - A tiny wiki using Goji, BoltDB and Blackfriday.
+* [ChainStore](https://github.com/pressly/chainstore) - Simple key-value interface to a variety of storage engines organized as a chain of operations.
+* [MetricBase](https://github.com/msiebuhr/MetricBase) - Single-binary version of Graphite.
+* [Gitchain](https://github.com/gitchain/gitchain) - Decentralized, peer-to-peer Git repositories aka "Git meets Bitcoin".
+* [event-shuttle](https://github.com/sclasen/event-shuttle) - A Unix system service to collect and reliably deliver messages to Kafka.
+* [ipxed](https://github.com/kelseyhightower/ipxed) - Web interface and api for ipxed.
+* [BoltStore](https://github.com/yosssi/boltstore) - Session store using Bolt.
+* [photosite/session](https://godoc.org/bitbucket.org/kardianos/photosite/session) - Sessions for a photo viewing site.
+* [LedisDB](https://github.com/siddontang/ledisdb) - A high performance NoSQL, using Bolt as optional storage.
+* [ipLocator](https://github.com/AndreasBriese/ipLocator) - A fast ip-geo-location-server using bolt with bloom filters.
+* [cayley](https://github.com/google/cayley) - Cayley is an open-source graph database using Bolt as optional backend.
+* [bleve](http://www.blevesearch.com/) - A pure Go search engine similar to ElasticSearch that uses Bolt as the default storage backend.
+* [tentacool](https://github.com/optiflows/tentacool) - REST api server to manage system stuff (IP, DNS, Gateway...) on a linux server.
+* [SkyDB](https://github.com/skydb/sky) - Behavioral analytics database.
+* [Seaweed File System](https://github.com/chrislusf/seaweedfs) - Highly scalable distributed key~file system with O(1) disk read.
+* [InfluxDB](https://influxdata.com) - Scalable datastore for metrics, events, and real-time analytics.
+* [Freehold](http://tshannon.bitbucket.org/freehold/) - An open, secure, and lightweight platform for your files and data.
+* [Prometheus Annotation Server](https://github.com/oliver006/prom_annotation_server) - Annotation server for PromDash & Prometheus service monitoring system.
+* [Consul](https://github.com/hashicorp/consul) - Consul is service discovery and configuration made easy. Distributed, highly available, and datacenter-aware.
+* [Kala](https://github.com/ajvb/kala) - Kala is a modern job scheduler optimized to run on a single node. It is persistent, JSON over HTTP API, ISO 8601 duration notation, and dependent jobs.
+* [drive](https://github.com/odeke-em/drive) - drive is an unofficial Google Drive command line client for \*NIX operating systems.
+* [stow](https://github.com/djherbis/stow) - a persistence manager for objects
+ backed by boltdb.
+* [buckets](https://github.com/joyrexus/buckets) - a bolt wrapper streamlining
+ simple tx and key scans.
+* [mbuckets](https://github.com/abhigupta912/mbuckets) - A Bolt wrapper that allows easy operations on multi level (nested) buckets.
+* [Request Baskets](https://github.com/darklynx/request-baskets) - A web service to collect arbitrary HTTP requests and inspect them via REST API or simple web UI, similar to [RequestBin](http://requestb.in/) service
+* [Go Report Card](https://goreportcard.com/) - Go code quality report cards as a (free and open source) service.
+* [Boltdb Boilerplate](https://github.com/bobintornado/boltdb-boilerplate) - Boilerplate wrapper around bolt aiming to make simple calls one-liners.
+* [lru](https://github.com/crowdriff/lru) - Easy to use Bolt-backed Least-Recently-Used (LRU) read-through cache with chainable remote stores.
+
+If you are using Bolt in a project please send a pull request to add it to the list.
diff --git a/libnetwork/vendor/github.com/codegangsta/cli/README.md b/libnetwork/vendor/github.com/codegangsta/cli/README.md
new file mode 100644
index 0000000000..fa220e2991
--- /dev/null
+++ b/libnetwork/vendor/github.com/codegangsta/cli/README.md
@@ -0,0 +1,316 @@
+[](https://travis-ci.org/codegangsta/cli)
+
+# cli.go
+`cli.go` is simple, fast, and fun package for building command line apps in Go. The goal is to enable developers to write fast and distributable command line applications in an expressive way.
+
+You can view the API docs here:
+http://godoc.org/github.com/codegangsta/cli
+
+## Overview
+Command line apps are usually so tiny that there is absolutely no reason why your code should *not* be self-documenting. Things like generating help text and parsing command flags/options should not hinder productivity when writing a command line app.
+
+**This is where `cli.go` comes into play.** `cli.go` makes command line programming fun, organized, and expressive!
+
+## Installation
+Make sure you have a working Go environment (go 1.1+ is *required*). [See the install instructions](http://golang.org/doc/install.html).
+
+To install `cli.go`, simply run:
+```
+$ go get github.com/codegangsta/cli
+```
+
+Make sure your `PATH` includes to the `$GOPATH/bin` directory so your commands can be easily used:
+```
+export PATH=$PATH:$GOPATH/bin
+```
+
+## Getting Started
+One of the philosophies behind `cli.go` is that an API should be playful and full of discovery. So a `cli.go` app can be as little as one line of code in `main()`.
+
+``` go
+package main
+
+import (
+ "os"
+ "github.com/codegangsta/cli"
+)
+
+func main() {
+ cli.NewApp().Run(os.Args)
+}
+```
+
+This app will run and show help text, but is not very useful. Let's give an action to execute and some help documentation:
+
+``` go
+package main
+
+import (
+ "os"
+ "github.com/codegangsta/cli"
+)
+
+func main() {
+ app := cli.NewApp()
+ app.Name = "boom"
+ app.Usage = "make an explosive entrance"
+ app.Action = func(c *cli.Context) {
+ println("boom! I say!")
+ }
+
+ app.Run(os.Args)
+}
+```
+
+Running this already gives you a ton of functionality, plus support for things like subcommands and flags, which are covered below.
+
+## Example
+
+Being a programmer can be a lonely job. Thankfully by the power of automation that is not the case! Let's create a greeter app to fend off our demons of loneliness!
+
+Start by creating a directory named `greet`, and within it, add a file, `greet.go` with the following code in it:
+
+``` go
+package main
+
+import (
+ "os"
+ "github.com/codegangsta/cli"
+)
+
+func main() {
+ app := cli.NewApp()
+ app.Name = "greet"
+ app.Usage = "fight the loneliness!"
+ app.Action = func(c *cli.Context) {
+ println("Hello friend!")
+ }
+
+ app.Run(os.Args)
+}
+```
+
+Install our command to the `$GOPATH/bin` directory:
+
+```
+$ go install
+```
+
+Finally run our new command:
+
+```
+$ greet
+Hello friend!
+```
+
+`cli.go` also generates some bitchass help text:
+
+```
+$ greet help
+NAME:
+ greet - fight the loneliness!
+
+USAGE:
+ greet [global options] command [command options] [arguments...]
+
+VERSION:
+ 0.0.0
+
+COMMANDS:
+ help, h Shows a list of commands or help for one command
+
+GLOBAL OPTIONS
+ --version Shows version information
+```
+
+### Arguments
+You can lookup arguments by calling the `Args` function on `cli.Context`.
+
+``` go
+...
+app.Action = func(c *cli.Context) {
+ println("Hello", c.Args()[0])
+}
+...
+```
+
+### Flags
+Setting and querying flags is simple.
+``` go
+...
+app.Flags = []cli.Flag {
+ cli.StringFlag{
+ Name: "lang",
+ Value: "english",
+ Usage: "language for the greeting",
+ },
+}
+app.Action = func(c *cli.Context) {
+ name := "someone"
+ if len(c.Args()) > 0 {
+ name = c.Args()[0]
+ }
+ if c.String("lang") == "spanish" {
+ println("Hola", name)
+ } else {
+ println("Hello", name)
+ }
+}
+...
+```
+
+See full list of flags at http://godoc.org/github.com/codegangsta/cli
+
+#### Alternate Names
+
+You can set alternate (or short) names for flags by providing a comma-delimited list for the `Name`. e.g.
+
+``` go
+app.Flags = []cli.Flag {
+ cli.StringFlag{
+ Name: "lang, l",
+ Value: "english",
+ Usage: "language for the greeting",
+ },
+}
+```
+
+That flag can then be set with `--lang spanish` or `-l spanish`. Note that giving two different forms of the same flag in the same command invocation is an error.
+
+#### Values from the Environment
+
+You can also have the default value set from the environment via `EnvVar`. e.g.
+
+``` go
+app.Flags = []cli.Flag {
+ cli.StringFlag{
+ Name: "lang, l",
+ Value: "english",
+ Usage: "language for the greeting",
+ EnvVar: "APP_LANG",
+ },
+}
+```
+
+The `EnvVar` may also be given as a comma-delimited "cascade", where the first environment variable that resolves is used as the default.
+
+``` go
+app.Flags = []cli.Flag {
+ cli.StringFlag{
+ Name: "lang, l",
+ Value: "english",
+ Usage: "language for the greeting",
+ EnvVar: "LEGACY_COMPAT_LANG,APP_LANG,LANG",
+ },
+}
+```
+
+### Subcommands
+
+Subcommands can be defined for a more git-like command line app.
+```go
+...
+app.Commands = []cli.Command{
+ {
+ Name: "add",
+ Aliases: []string{"a"},
+ Usage: "add a task to the list",
+ Action: func(c *cli.Context) {
+ println("added task: ", c.Args().First())
+ },
+ },
+ {
+ Name: "complete",
+ Aliases: []string{"c"},
+ Usage: "complete a task on the list",
+ Action: func(c *cli.Context) {
+ println("completed task: ", c.Args().First())
+ },
+ },
+ {
+ Name: "template",
+ Aliases: []string{"r"},
+ Usage: "options for task templates",
+ Subcommands: []cli.Command{
+ {
+ Name: "add",
+ Usage: "add a new template",
+ Action: func(c *cli.Context) {
+ println("new task template: ", c.Args().First())
+ },
+ },
+ {
+ Name: "remove",
+ Usage: "remove an existing template",
+ Action: func(c *cli.Context) {
+ println("removed task template: ", c.Args().First())
+ },
+ },
+ },
+ },
+}
+...
+```
+
+### Bash Completion
+
+You can enable completion commands by setting the `EnableBashCompletion`
+flag on the `App` object. By default, this setting will only auto-complete to
+show an app's subcommands, but you can write your own completion methods for
+the App or its subcommands.
+```go
+...
+var tasks = []string{"cook", "clean", "laundry", "eat", "sleep", "code"}
+app := cli.NewApp()
+app.EnableBashCompletion = true
+app.Commands = []cli.Command{
+ {
+ Name: "complete",
+ Aliases: []string{"c"},
+ Usage: "complete a task on the list",
+ Action: func(c *cli.Context) {
+ println("completed task: ", c.Args().First())
+ },
+ BashComplete: func(c *cli.Context) {
+ // This will complete if no args are passed
+ if len(c.Args()) > 0 {
+ return
+ }
+ for _, t := range tasks {
+ fmt.Println(t)
+ }
+ },
+ }
+}
+...
+```
+
+#### To Enable
+
+Source the `autocomplete/bash_autocomplete` file in your `.bashrc` file while
+setting the `PROG` variable to the name of your program:
+
+`PROG=myprogram source /.../cli/autocomplete/bash_autocomplete`
+
+#### To Distribute
+
+Copy `autocomplete/bash_autocomplete` into `/etc/bash_completion.d/` and rename
+it to the name of the program you wish to add autocomplete support for (or
+automatically install it there if you are distributing a package). Don't forget
+to source the file to make it active in the current shell.
+
+```
+ sudo cp src/bash_autocomplete /etc/bash_completion.d/| Internet Relay Chat (IRC) | +
+
+ IRC is a direct line to our most knowledgeable Docker users; we have
+ both the |
+
| Docker Community Forums | ++ The Docker Engine + group is for users of the Docker Engine project. + | +
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| + You can follow Docker's Twitter feed + to get updates on our products. You can also tweet us questions or just + share blogs or stories. + | +|
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