rpc: add new client, use it everywhere

The new client implementation supports concurrent requests,
subscriptions and replaces the various ad hoc RPC clients
throughout go-ethereum.

cmd/geth/consolecmd.go

@@ -19,9 +19,12 @@ package main
 import (
 	"os"
 	"os/signal"
+	"strings"
 
 	"github.com/ethereum/go-ethereum/cmd/utils"
 	"github.com/ethereum/go-ethereum/console"
+	"github.com/ethereum/go-ethereum/node"
+	"github.com/ethereum/go-ethereum/rpc"
 	"gopkg.in/urfave/cli.v1"
 )
 
@@ -99,7 +102,7 @@ func localConsole(ctx *cli.Context) error {
 // console to it.
 func remoteConsole(ctx *cli.Context) error {
 	// Attach to a remotely running geth instance and start the JavaScript console
-	client, err := utils.NewRemoteRPCClient(ctx)
+	client, err := dialRPC(ctx.Args().First())
 	if err != nil {
 		utils.Fatalf("Unable to attach to remote geth: %v", err)
 	}
@@ -127,6 +130,20 @@ func remoteConsole(ctx *cli.Context) error {
 	return nil
 }
 
+// dialRPC returns a RPC client which connects to the given endpoint.
+// The check for empty endpoint implements the defaulting logic
+// for "geth attach" and "geth monitor" with no argument.
+func dialRPC(endpoint string) (*rpc.Client, error) {
+	if endpoint == "" {
+		endpoint = node.DefaultIPCEndpoint()
+	} else if strings.HasPrefix(endpoint, "rpc:") || strings.HasPrefix(endpoint, "ipc:") {
+		// Backwards compatibility with geth < 1.5 which required
+		// these prefixes.
+		endpoint = endpoint[4:]
+	}
+	return rpc.Dial(endpoint)
+}
+
 // ephemeralConsole starts a new geth node, attaches an ephemeral JavaScript
 // console to it, and each of the files specified as arguments and tears the
 // everything down.