*: initial implementation of grpc-proxy

etcdmain/grpc_proxy.go

@@ -0,0 +1,132 @@
+// Copyright 2016 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package etcdmain
+
+import (
+	"fmt"
+	"net"
+	"os"
+	"time"
+
+	"github.com/coreos/etcd/clientv3"
+	pb "github.com/coreos/etcd/etcdserver/etcdserverpb"
+	"github.com/coreos/etcd/pkg/transport"
+	"github.com/coreos/etcd/proxy/grpcproxy"
+
+	"github.com/spf13/cobra"
+	"google.golang.org/grpc"
+)
+
+var (
+	grpcProxyListenAddr string
+	grpcProxyEndpoints  []string
+	grpcProxyCert       string
+	grpcProxyKey        string
+	grpcProxyCA         string
+)
+
+func init() {
+	rootCmd.AddCommand(newGRPCProxyCommand())
+}
+
+// newGRPCProxyCommand returns the cobra command for "grpc-proxy".
+func newGRPCProxyCommand() *cobra.Command {
+	lpc := &cobra.Command{
+		Use:   "grpc-proxy <subcommand>",
+		Short: "grpc-proxy related command",
+	}
+	lpc.AddCommand(newGRPCProxyStartCommand())
+
+	return lpc
+}
+
+func newGRPCProxyStartCommand() *cobra.Command {
+	cmd := cobra.Command{
+		Use:   "start",
+		Short: "start the grpc proxy",
+		Run:   startGRPCProxy,
+	}
+
+	cmd.Flags().StringVar(&grpcProxyListenAddr, "listen-addr", "127.0.0.1:23790", "listen address")
+	cmd.Flags().StringSliceVar(&grpcProxyEndpoints, "endpoints", []string{"127.0.0.1:2379"}, "comma separated etcd cluster endpoints")
+	cmd.Flags().StringVar(&grpcProxyCert, "cert", "", "identify secure connections with etcd servers using this TLS certificate file")
+	cmd.Flags().StringVar(&grpcProxyKey, "key", "", "identify secure connections with etcd servers using this TLS key file")
+	cmd.Flags().StringVar(&grpcProxyCA, "cacert", "", "verify certificates of TLS-enabled secure etcd servers using this CA bundle")
+
+	return &cmd
+}
+
+func startGRPCProxy(cmd *cobra.Command, args []string) {
+	l, err := net.Listen("tcp", grpcProxyListenAddr)
+	if err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(1)
+	}
+
+	cfg, err := newClientCfg()
+	if err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(1)
+	}
+
+	client, err := clientv3.New(*cfg)
+	if err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(1)
+	}
+
+	kvp := grpcproxy.NewKvProxy(client)
+
+	server := grpc.NewServer()
+	pb.RegisterKVServer(server, kvp)
+
+	server.Serve(l)
+}
+
+func newClientCfg() (*clientv3.Config, error) {
+	// set tls if any one tls option set
+	var cfgtls *transport.TLSInfo
+	tlsinfo := transport.TLSInfo{}
+	if grpcProxyCert != "" {
+		tlsinfo.CertFile = grpcProxyCert
+		cfgtls = &tlsinfo
+	}
+
+	if grpcProxyKey != "" {
+		tlsinfo.KeyFile = grpcProxyKey
+		cfgtls = &tlsinfo
+	}
+
+	if grpcProxyCA != "" {
+		tlsinfo.CAFile = grpcProxyCA
+		cfgtls = &tlsinfo
+	}
+
+	cfg := clientv3.Config{
+		Endpoints:   grpcProxyEndpoints,
+		DialTimeout: 5 * time.Second,
+	}
+	if cfgtls != nil {
+		clientTLS, err := cfgtls.ClientConfig()
+		if err != nil {
+			return nil, err
+		}
+		cfg.TLS = clientTLS
+	}
+
+	// TODO: support insecure tls
+
+	return &cfg, nil
+}

etcdmain/main.go

@@ -24,7 +24,7 @@ func Main() {
 
 	if len(os.Args) > 1 {
 		switch os.Args[1] {
-		case "gateway":
+		case "gateway", "grpc-proxy":
 			if err := rootCmd.Execute(); err != nil {
 				fmt.Fprint(os.Stderr, err)
 				os.Exit(1)

proxy/grpcproxy/cache/store.go

@@ -15,6 +15,7 @@
 package cache
 
 import (
+	"errors"
 	"sync"
 
 	"github.com/coreos/etcd/etcdserver/api/v3rpc/rpctypes"
@@ -45,7 +46,8 @@ func keyFunc(req *pb.RangeRequest) string {
 
 func NewCache(maxCacheEntries int) Cache {
 	return &cache{
-		lru: lru.New(maxCacheEntries),
+		lru:          lru.New(maxCacheEntries),
+		compactedRev: -1,
 	}
 }
 
@@ -76,7 +78,7 @@ func (c *cache) Get(req *pb.RangeRequest) (*pb.RangeResponse, error) {
 	c.mu.Lock()
 	defer c.mu.Unlock()
 
-	if req.Revision > c.compactedRev {
+	if req.Revision < c.compactedRev {
 		c.lru.Remove(key)
 		return nil, ErrCompacted
 	}
@@ -84,7 +86,7 @@ func (c *cache) Get(req *pb.RangeRequest) (*pb.RangeResponse, error) {
 	if resp, ok := c.lru.Get(key); ok {
 		return resp.(*pb.RangeResponse), nil
 	}
-	return nil, nil
+	return nil, errors.New("not exist")
 }
 
 // Compact invalidate all caching response before the given rev.

proxy/grpcproxy/kv.go

@@ -18,6 +18,7 @@ import (
 	"github.com/coreos/etcd/clientv3"
 	pb "github.com/coreos/etcd/etcdserver/etcdserverpb"
 	"github.com/coreos/etcd/proxy/grpcproxy/cache"
+
 	"golang.org/x/net/context"
 )
 
@@ -36,17 +37,23 @@ func NewKvProxy(c *clientv3.Client) *kvProxy {
 func (p *kvProxy) Range(ctx context.Context, r *pb.RangeRequest) (*pb.RangeResponse, error) {
 	// if request set Serializable, serve it from local cache first
 	if r.Serializable {
-		if resp, err := p.cache.Get(r); err == nil || err == cache.ErrCompacted {
-			return resp, err
+		resp, err := p.cache.Get(r)
+		switch err {
+		case nil:
+			return resp, nil
+		case cache.ErrCompacted:
+			return nil, err
 		}
 	}
 
 	resp, err := p.c.Do(ctx, RangeRequestToOp(r))
 	if err != nil {
-		p.cache.Add(r, (*pb.RangeResponse)(resp.Get()))
+		return nil, err
 	}
 
-	return (*pb.RangeResponse)(resp.Get()), err
+	p.cache.Add(r, (*pb.RangeResponse)(resp.Get()))
+
+	return (*pb.RangeResponse)(resp.Get()), nil
 }
 
 func (p *kvProxy) Put(ctx context.Context, r *pb.PutRequest) (*pb.PutResponse, error) {