path: root/rpc/comms/ipc.go

package comms

import (
    "fmt"
    "math/rand"
    "net"

    "encoding/json"

    "github.com/ethereum/go-ethereum/rpc/codec"
    "github.com/ethereum/go-ethereum/rpc/shared"
)

type IpcConfig struct {
    Endpoint string
}

type ipcClient struct {
    endpoint string
    c        net.Conn
    codec    codec.Codec
    coder    codec.ApiCoder
}

func (self *ipcClient) Close() {
    self.coder.Close()
}

func (self *ipcClient) Send(req interface{}) error {
    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) {
    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
func NewIpcClient(cfg IpcConfig, codec codec.Codec) (*ipcClient, error) {
    return newIpcClient(cfg, codec)
}

// Start IPC server
func StartIpc(cfg IpcConfig, codec codec.Codec, offeredApi shared.EthereumApi) error {
    return startIpc(cfg, codec, offeredApi)
}

func newIpcConnId() int {
    return rand.Int() % 1000000
}