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diff --git a/vendor/github.com/docker/libkv/docs/compatibility.md b/vendor/github.com/docker/libkv/docs/compatibility.md
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+#Cross-Backend Compatibility
+
+The value of `libkv` is not to duplicate the code for programs that should support multiple distributed K/V stores like the classic `Consul`/`etcd`/`zookeeper` trio.
+
+This document provides with general guidelines for users willing to support those backends with the same code using `libkv`.
+
+Please note that most of those workarounds are going to disappear in the future with `etcd` APIv3.
+
+##Etcd directory/key distinction
+
+`etcd` with APIv2 makes the distinction between keys and directories. The result with `libkv` is that when using the etcd driver:
+
+- You cannot store values on directories
+- You cannot invoke `WatchTree` (watching on child values), on a regular key
+
+This is fundamentaly different than `Consul` and `zookeeper` which are more permissive and allow the same set of operations on keys and directories (called a Node for zookeeper).
+
+Apiv3 is in the work for `etcd`, which removes this key/directory distinction, but until then you should follow these workarounds to make your `libkv` code work across backends.
+
+###Put
+
+`etcd` cannot put values on directories, so this puts a major restriction compared to `Consul` and `zookeeper`.
+
+If you want to support all those three backends, you should make sure to only put data on **leaves**.
+
+For example:
+
+```go
+_ := kv.Put("path/to/key/bis", []byte("foo"), nil)
+_ := kv.Put("path/to/key", []byte("bar"), nil)
+```
+
+Will work on `Consul` and `zookeeper` but fail for `etcd`. This is because the first `Put` in the case of `etcd` will recursively create the directory hierarchy and `path/to/key` is now considered as a directory. Thus, values should always be stored on leaves if the support for the three backends is planned.
+
+###WatchTree
+
+When initializing the `WatchTree`, the natural way to do so is through the following code:
+
+```go
+key := "path/to/key"
+if !kv.Exists(key) {
+    err := kv.Put(key, []byte("data"), nil)
+}
+events, err := kv.WatchTree(key, nil)
+```
+
+The code above will not work across backends and etcd will fail on the `WatchTree` call. What happens exactly:
+
+- `Consul` will create a regular `key` because it has no distinction between directories and keys. This is not an issue as we can invoke `WatchTree` on regular keys.
+- `zookeeper` is going to create a `node` that can either be a directory or a key during the lifetime of a program but it does not matter as a directory can hold values and be watchable like a regular key.
+- `etcd` is going to create a regular `key`. We cannot invoke `WatchTree` on regular keys using etcd.
+
+To be cross-compatible between those three backends for `WatchTree`, we need to enforce a parameter that is only interpreted with `etcd` and which tells the client to create a `directory` instead of a key.
+
+```go
+key := "path/to/key"
+if !kv.Exists(key) {
+    // We enforce IsDir = true to make sure etcd creates a directory
+    err := kv.Put(key, []byte("data"), &store.WriteOptions{IsDir:true})
+}
+events, err := kv.WatchTree(key, nil)
+```
+
+The code above will work for the three backends but make sure to not try to store any value at that path as the call to `Put` will fail for `etcd` (you can only put at `path/to/key/foo`, `path/to/key/bar` for example).
+
+##Etcd distributed locking
+
+There is `Lock` mechanisms baked in the `coreos/etcd/client` for now. Instead, `libkv` has its own implementation of a `Lock` on top of `etcd`.
+
+The general workflow for the `Lock` is as follows:
+
+- Call Lock concurrently on a `key` between threads/programs
+- Only one will create that key, others are going to fail because the key has already been created
+- The thread locking the key can get the right index to set the value of the key using Compare And Swap and effectively Lock and hold the key
+- Other threads are given a wrong index to fail the Compare and Swap and block until the key has been released by the thread holding the Lock
+- Lock seekers are setting up a Watch listening on that key and events happening on the key
+- When the thread/program stops holding the lock, it deletes the key triggering a `delete` event that will notify all the other threads. In case the program crashes, the key has a TTL attached that will send an `expire` event when this TTL expires.
+- Once everyone is notified, back to the first step. First come, first served with the Lock.
+
+The whole Lock process is highly dependent on the `delete`/`expire` events of `etcd`. So don't expect the key to be still there once the Lock is released.
+
+For example if the whole logic is to `Lock` a key and expect the value to still be there after it has been unlocked, it is not going to be cross-backend compatible with `Consul` and `zookeeper`. On the other end the `etcd` Lock can still be used to do Leader Election for example and still be cross-compatible with other backends.
+\ No newline at end of file
diff --git a/vendor/github.com/docker/libkv/docs/examples.md b/vendor/github.com/docker/libkv/docs/examples.md
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+++ b/vendor/github.com/docker/libkv/docs/examples.md
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+#Examples
+
+This document contains useful example of usage for `libkv`. It might not be complete but provides with general informations on how to use the client.
+
+##Create a store and use Put/Get/Delete
+
+```go
+package main
+
+import (
+    "fmt"
+    "time"
+    "log"
+
+    "github.com/docker/libkv"
+    "github.com/docker/libkv/store"
+    "github.com/docker/libkv/store/consul"
+)
+
+func init() {
+    // Register consul store to libkv
+    consul.Register()
+
+    // We can register as many backends that are supported by libkv
+    etcd.Register()
+    zookeeper.Register()
+    boltdb.Register()
+}
+
+func main() {
+    client := "localhost:8500"
+
+    // Initialize a new store with consul
+    kv, err := libkv.NewStore(
+        store.CONSUL, // or "consul"
+        []string{client},
+        &store.Config{
+            ConnectionTimeout: 10*time.Second,
+        },
+    )
+    if err != nil {
+        log.Fatal("Cannot create store consul")
+    }
+
+    key := "foo"
+    err = kv.Put(key, []byte("bar"), nil)
+    if err != nil {
+        fmt.Errorf("Error trying to put value at key: %v", key)
+    }
+
+    pair, err := kv.Get(key)
+    if err != nil {
+        fmt.Errorf("Error trying accessing value at key: %v", key)
+    }
+
+    err = kv.Delete(key)
+    if err != nil {
+        fmt.Errorf("Error trying to delete key %v", key)
+    }
+
+    log.Info("value: ", string(pair.Value))
+}
+```
+
+##List keys
+
+```go
+// List will list all the keys under `key` if it contains a set of child keys/values
+entries, err := kv.List(key)
+for _, pair := range entries {
+    fmt.Printf("key=%v - value=%v", pair.Key, string(pair.Value))
+}
+
+```
+
+##Watching for events on a single key (Watch)
+
+You can use watches to watch modifications on a key. First you need to check if the key exists. If this is not the case, we need to create it using the `Put` function.
+
+```go
+// Checking on the key before watching
+if !kv.Exists(key) {
+    err := kv.Put(key, []byte("bar"), nil)
+    if err != nil {
+        fmt.Errorf("Something went wrong when initializing key %v", key)
+    }
+}
+
+stopCh := make(<-chan struct{})
+events, err := kv.Watch(key, stopCh)
+
+select {
+    case pair := <-events:
+        // Do something with events
+        fmt.Printf("value changed on key %v: new value=%v", key, pair.Value)
+}
+
+```
+
+##Watching for events happening on child keys (WatchTree)
+
+You can use watches to watch modifications on a key. First you need to check if the key exists. If this is not the case, we need to create it using the `Put` function. There is a special step here though if you want your code to work across backends. Because `etcd` is a special case and it makes the distinction between directories and keys, we need to make sure that the created key is considered as a directory by enforcing `IsDir` at `true`.
+
+```go
+// Checking on the key before watching
+if !kv.Exists(key) {
+    // Don't forget IsDir:true if the code is used cross-backend
+    err := kv.Put(key, []byte("bar"), &store.WriteOptions{IsDir:true})
+    if err != nil {
+        fmt.Errorf("Something went wrong when initializing key %v", key)
+    }
+}
+
+stopCh := make(<-chan struct{})
+events, err := kv.WatchTree(key, stopCh)
+
+select {
+    case pairs := <-events:
+        // Do something with events
+        for _, pair := range pairs {
+            fmt.Printf("value changed on key %v: new value=%v", key, pair.Value)
+        }
+}
+
+```
+
+## Distributed Locking, using Lock/Unlock
+
+```go
+key := "lockKey"
+value := []byte("bar")
+
+// Initialize a distributed lock. TTL is optional, it is here to make sure that
+// the lock is released after the program that is holding the lock ends or crashes
+lock, err := kv.NewLock(key, &store.LockOptions{Value: value, TTL: 2 * time.Second})
+if err != nil {
+    fmt.Errorf("something went wrong when trying to initialize the Lock")
+}
+
+// Try to lock the key, the call to Lock() is blocking
+_, err := lock.Lock(nil)
+if err != nil {
+    fmt.Errorf("something went wrong when trying to lock key %v", key)
+}
+
+// Get should work because we are holding the key
+pair, err := kv.Get(key)
+if err != nil {
+    fmt.Errorf("key %v has value %v", key, pair.Value)
+}
+
+// Unlock the key
+err = lock.Unlock()
+if err != nil {
+    fmt.Errorf("something went wrong when trying to unlock key %v", key)
+}
+```
+\ No newline at end of file