added attach over ipc command

rpc/comms/ipc.go

@@ -1,8 +1,13 @@
 package comms
 
 import (
+	"fmt"
+	"net"
+
 	"github.com/ethereum/go-ethereum/rpc/api"
 	"github.com/ethereum/go-ethereum/rpc/codec"
+	"github.com/ethereum/go-ethereum/rpc/shared"
+	"encoding/json"
 )
 
 type IpcConfig struct {
@@ -10,19 +15,74 @@ type IpcConfig struct {
 }
 
 type ipcClient struct {
-	codec codec.ApiCoder
+	endpoint string
+	codec    codec.Codec
+	coder    codec.ApiCoder
 }
 
 func (self *ipcClient) Close() {
-	self.codec.Close()
+	self.coder.Close()
 }
 
 func (self *ipcClient) Send(req interface{}) error {
-	return self.codec.WriteResponse(req)
+	var err error
+	if r, ok := req.(*shared.Request); ok {
+		if err = self.coder.WriteResponse(r); err != nil {
+			if _, ok := err.(*net.OpError); ok { // connection lost, retry once
+				if err = self.reconnect(); err == nil {
+					err = self.coder.WriteResponse(r)
+				}
+			}
+		}
+		return err
+	}
+
+	return fmt.Errorf("Invalid request (%T)", req)
 }
 
 func (self *ipcClient) Recv() (interface{}, error) {
-	return self.codec.ReadResponse()
+	res, err := self.coder.ReadResponse()
+	if err != nil {
+		return nil, err
+	}
+
+	if r, ok := res.(shared.SuccessResponse); ok {
+		return r.Result, nil
+	}
+
+	if r, ok := res.(shared.ErrorResponse); ok {
+		return r.Error, nil
+	}
+
+	return res, err
+}
+
+func (self *ipcClient) SupportedModules() (map[string]string, error) {
+	req := shared.Request{
+		Id:      1,
+		Jsonrpc: "2.0",
+		Method:  "modules",
+	}
+
+	if err := self.coder.WriteResponse(req); err != nil {
+		return nil, err
+	}
+
+	res, err := self.coder.ReadResponse()
+	if err != nil {
+		return nil, err
+	}
+
+	if sucRes, ok := res.(shared.SuccessResponse); ok {
+		data, _ := json.Marshal(sucRes.Result)
+		modules := make(map[string]string)
+		err = json.Unmarshal(data, &modules)
+		if err == nil {
+			return modules, nil
+		}
+	}
+
+	return nil, fmt.Errorf("Invalid response")
 }
 
 // Create a new IPC client, UNIX domain socket on posix, named pipe on Windows