Add support for memo backend.

.travis.yml

@@ -18,14 +18,18 @@ before_script:
   - script/travis_consul.sh 0.6.3
   - script/travis_etcd.sh 3.0.0
   - script/travis_zk.sh 3.5.1-alpha
+  - script/travis_memo.sh 0.9.2
 
 script:
   - ./consul agent -server -bootstrap -advertise=127.0.0.1 -data-dir /tmp/consul -config-file=./config.json 1>/dev/null &
   - ./etcd/etcd --listen-client-urls 'http://0.0.0.0:4001' --advertise-client-urls 'http://127.0.0.1:4001' >/dev/null 2>&1 &
-  - ./zk/bin/zkServer.sh start ./zk/conf/zoo.cfg 1> /dev/null
+  - ./script/travis_start_zk.sh
+  - ./memo/bin/memo kvs run kvs --allow-root-creation --grpc localhost:9000 >/dev/null 2>&1 &
   - script/validate-gofmt
   - go vet ./...
   - fgt golint ./...
   - go test -v -race ./...
   - script/coverage
   - goveralls -service=travis-ci -coverprofile=goverage.report
+
+dist: trusty

README.md

@@ -34,6 +34,7 @@ You can find examples of usage for `libkv` under in `docs/examples.go`. Optional
 - Etcd versions >= `2.0` because it uses the new `coreos/etcd/client`, this might change in the future as the support for `APIv3` comes along and adds more capabilities.
 - Zookeeper versions >= `3.4.5`. Although this might work with previous version but this remains untested as of now.
 - Boltdb, which shouldn't be subject to any version dependencies.
+- Memo version >= 0.9.2.
 
 ## Interface
 
@@ -62,19 +63,19 @@ Backend drivers in `libkv` are generally divided between **local drivers** and *
 
 Local drivers are usually used in complement to the distributed drivers to store informations that only needs to be available locally.
 
-| Calls                 |   Consul   |  Etcd  |  Zookeeper  |  BoltDB  |
-|-----------------------|:----------:|:------:|:-----------:|:--------:|
-| Put                   |     X      |   X    |      X      |    X     |
-| Get                   |     X      |   X    |      X      |    X     |
-| Delete                |     X      |   X    |      X      |    X     |
-| Exists                |     X      |   X    |      X      |    X     |
-| Watch                 |     X      |   X    |      X      |          |
-| WatchTree             |     X      |   X    |      X      |          |
-| NewLock (Lock/Unlock) |     X      |   X    |      X      |          |
-| List                  |     X      |   X    |      X      |    X     |
-| DeleteTree            |     X      |   X    |      X      |    X     |
-| AtomicPut             |     X      |   X    |      X      |    X     |
-| Close                 |     X      |   X    |      X      |    X     |
+| Calls                 |   Consul   |  Etcd  |  Zookeeper  |  BoltDB  |  Memo  |
+|-----------------------|:----------:|:------:|:-----------:|:--------:|:------:|
+| Put                   |     X      |   X    |      X      |    X     |    X   |
+| Get                   |     X      |   X    |      X      |    X     |    X   |
+| Delete                |     X      |   X    |      X      |    X     |    X   |
+| Exists                |     X      |   X    |      X      |    X     |    X   |
+| Watch                 |     X      |   X    |      X      |          |        |
+| WatchTree             |     X      |   X    |      X      |          |        |
+| NewLock (Lock/Unlock) |     X      |   X    |      X      |          |        |
+| List                  |     X      |   X    |      X      |    X     |    X   |
+| DeleteTree            |     X      |   X    |      X      |    X     |    X   |
+| AtomicPut             |     X      |   X    |      X      |    X     |        |
+| Close                 |     X      |   X    |      X      |    X     |    X   |
 
 ## Limitations
 
@@ -104,4 +105,4 @@ Want to hack on libkv? [Docker's contributions guidelines](https://github.com/do
 
 ## Copyright and license
 
-Copyright © 2014-2016 Docker, Inc. All rights reserved, except as follows. Code is released under the Apache 2.0 license. The README.md file, and files in the "docs" folder are licensed under the Creative Commons Attribution 4.0 International License under the terms and conditions set forth in the file "LICENSE.docs". You may obtain a duplicate copy of the same license, titled CC-BY-SA-4.0, at http://creativecommons.org/licenses/by/4.0/.
+Copyright © 2014-2017 Docker, Inc. All rights reserved, except as follows. Code is released under the Apache 2.0 license. The README.md file, and files in the "docs" folder are licensed under the Creative Commons Attribution 4.0 International License under the terms and conditions set forth in the file "LICENSE.docs". You may obtain a duplicate copy of the same license, titled CC-BY-SA-4.0, at http://creativecommons.org/licenses/by/4.0/.

script/travis_memo.sh

@@ -0,0 +1,17 @@
+#!/bin/bash
+
+VERSION=$1
+if test -z "$VERSION"; then
+  VERSION=0.9.2
+fi
+
+tarball=https://storage.googleapis.com/sh_infinit_releases/linux64/memo-x86_64-linux_debian_oldstable-gcc4-$VERSION.tbz
+
+wget "$tarball"
+tar -xvf memo-x86_64-linux_debian_oldstable-gcc4-$VERSION.tbz
+mv memo-x86_64-linux_debian_oldstable-gcc4-$VERSION memo
+
+memo/bin/memo user create
+memo/bin/memo silo create filesystem silo
+memo/bin/memo network create network --silo silo
+memo/bin/memo kvs create --name kvs --network network

script/travis_start_zk.sh

@@ -0,0 +1,11 @@
+#! /bin/bash
+
+while true; do
+  ./zk/bin/zkServer.sh start ./zk/conf/zoo.cfg
+  sleep 3
+  if echo stat |nc localhost 2181 |grep -q Mode; then
+    break
+  fi
+  echo zk did not start properly, retrying...
+  ./zk/bin/zkServer.sh stop
+done

store/memo/memo.go

@@ -0,0 +1,137 @@
+package memo
+
+import (
+	"github.com/docker/libkv"
+	"github.com/docker/libkv/store"
+	kvs "github.com/docker/libkv/store/memo/memo_kvs"
+	"golang.org/x/net/context"
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/codes"
+)
+
+// Memo is the receiver type for the Store interface
+type Memo struct {
+	kvs kvs.KeyValueStoreClient
+}
+
+// Register registers memo to libkv
+func Register() {
+	libkv.AddStore("memo", New)
+}
+
+// New creates a new memo client
+func New(addrs []string, options *store.Config) (store.Store, error) {
+	conn, err := grpc.Dial(addrs[0], grpc.WithInsecure())
+	if err != nil {
+		return nil, err
+	}
+	kvs := kvs.NewKeyValueStoreClient(conn)
+	return &Memo{kvs: kvs}, nil
+}
+
+// Get current value at "key".
+func (s *Memo) Get(key string) (*store.KVPair, error) {
+	res, err := s.kvs.Fetch(context.Background(), &kvs.FetchRequest{Key: key})
+	if err != nil {
+		if grpc.Code(err) == codes.NotFound {
+			return nil, store.ErrKeyNotFound
+		}
+		return nil, err
+	}
+	return &store.KVPair{
+		Key:       key,
+		Value:     res.Value,
+		LastIndex: 0,
+	}, nil
+}
+
+// Put value at "key"
+func (s *Memo) Put(key string, value []byte, options *store.WriteOptions) error {
+	_, err := s.kvs.Upsert(context.Background(),
+		&kvs.UpsertRequest{Key: key, Value: value})
+	return err
+}
+
+// Delete value at "key"
+func (s *Memo) Delete(key string) error {
+	_, err := s.kvs.Delete(context.Background(), &kvs.DeleteRequest{Key: key})
+	if err != nil && grpc.Code(err) == codes.NotFound {
+		return store.ErrKeyNotFound
+	}
+	return err
+}
+
+// Exists checks if "key" is present in the store
+func (s *Memo) Exists(key string) (bool, error) {
+	_, err := s.kvs.Fetch(context.Background(), &kvs.FetchRequest{Key: key})
+	if err == nil {
+		return true, nil
+	}
+	if grpc.Code(err) == codes.NotFound {
+		return false, nil
+	}
+	return false, err
+}
+
+// Watch for changes. Not supported by memo.
+func (s *Memo) Watch(key string, stopCh <-chan struct{}) (<-chan *store.KVPair, error) {
+	return nil, store.ErrCallNotSupported
+}
+
+// WatchTree for changes. Not supported by memo.
+func (s *Memo) WatchTree(directory string, stopCh <-chan struct{}) (<-chan []*store.KVPair, error) {
+	return nil, store.ErrCallNotSupported
+}
+
+// NewLock is not supported by memo.
+func (s *Memo) NewLock(key string, options *store.LockOptions) (store.Locker, error) {
+	return nil, store.ErrCallNotSupported
+}
+
+// List keys with given prefix.
+func (s *Memo) List(directory string) ([]*store.KVPair, error) {
+	keys, err := s.kvs.List(context.Background(),
+		&kvs.ListRequest{Prefix: directory, MaxKeys: 1000000000})
+	if err != nil {
+		return nil, err
+	}
+	var res []*store.KVPair
+	for _, k := range keys.Items {
+		kv, err := s.Get(k.Key)
+		if err != nil {
+			return nil, err
+		}
+		res = append(res, kv)
+	}
+	if len(res) == 0 {
+		return nil, store.ErrKeyNotFound
+	}
+	return res, nil
+}
+
+// DeleteTree deletes all entries with given prefix.
+func (s *Memo) DeleteTree(directory string) error {
+	keys, err := s.kvs.List(context.Background(),
+		&kvs.ListRequest{Prefix: directory, MaxKeys: 1000000000})
+	if err != nil {
+		return err
+	}
+	for _, k := range keys.Items {
+		s.Delete(k.Key)
+	}
+	return nil
+}
+
+// AtomicPut is not supported by memo.
+func (s *Memo) AtomicPut(key string, value []byte, previous *store.KVPair, options *store.WriteOptions) (bool, *store.KVPair, error) {
+	return false, nil, store.ErrCallNotSupported
+}
+
+// AtomicDelete is not supported by memo.
+func (s *Memo) AtomicDelete(key string, previous *store.KVPair) (bool, error) {
+	return false, store.ErrCallNotSupported
+}
+
+// Close the connection
+func (s *Memo) Close() {
+}