path: root/rpc/jeth.go

// Copyright 2015 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.

package rpc

import (
    "encoding/json"
    "fmt"

    "github.com/ethereum/go-ethereum/cmd/utils"
    "github.com/ethereum/go-ethereum/jsre"
    "github.com/ethereum/go-ethereum/logger"
    "github.com/ethereum/go-ethereum/logger/glog"
    "github.com/ethereum/go-ethereum/rpc/comms"
    "github.com/ethereum/go-ethereum/rpc/shared"
    "github.com/ethereum/go-ethereum/rpc/useragent"
    "github.com/ethereum/go-ethereum/xeth"

    "github.com/robertkrimen/otto"
)

type Jeth struct {
    ethApi shared.EthereumApi
    re     *jsre.JSRE
    client comms.EthereumClient
    fe     xeth.Frontend
}

func NewJeth(ethApi shared.EthereumApi, re *jsre.JSRE, client comms.EthereumClient, fe xeth.Frontend) *Jeth {
    // enable the jeth as the user agent
    req := shared.Request{
        Id:      0,
        Method:  useragent.EnableUserAgentMethod,
        Jsonrpc: shared.JsonRpcVersion,
        Params:  []byte("[]"),
    }
    client.Send(&req)
    client.Recv()

    return &Jeth{ethApi, re, client, fe}
}

func (self *Jeth) err(call otto.FunctionCall, code int, msg string, id interface{}) (response otto.Value) {
    errObj := fmt.Sprintf("{\"message\": \"%s\", \"code\": %d}", msg, code)
    retResponse := fmt.Sprintf("ret_response = JSON.parse('{\"jsonrpc\": \"%s\", \"id\": %v, \"error\": %s}');", shared.JsonRpcVersion, id, errObj)

    call.Otto.Run("ret_error = " + errObj)
    res, _ := call.Otto.Run(retResponse)

    return res
}

func (self *Jeth) Send(call otto.FunctionCall) (response otto.Value) {
    reqif, err := call.Argument(0).Export()
    if err != nil {
        return self.err(call, -32700, err.Error(), nil)
    }

    jsonreq, err := json.Marshal(reqif)
    var reqs []shared.Request
    batch := true
    err = json.Unmarshal(jsonreq, &reqs)
    if err != nil {
        reqs = make([]shared.Request, 1)
        err = json.Unmarshal(jsonreq, &reqs[0])
        batch = false
    }

    call.Otto.Set("response_len", len(reqs))
    call.Otto.Run("var ret_response = new Array(response_len);")

    for i, req := range reqs {
        var respif interface{}
        err := self.client.Send(&req)
        if err != nil {
            return self.err(call, -32603, err.Error(), req.Id)
        }

    recv:
        respif, err = self.client.Recv()
        if err != nil {
            return self.err(call, -32603, err.Error(), req.Id)
        }

        agentreq, isRequest := respif.(*shared.Request)
        if isRequest {
            self.handleRequest(agentreq)
            goto recv // receive response after agent interaction
        }

        sucres, isSuccessResponse := respif.(*shared.SuccessResponse)
        errres, isErrorResponse := respif.(*shared.ErrorResponse)
        if !isSuccessResponse && !isErrorResponse {
            return self.err(call, -32603, fmt.Sprintf("Invalid response type (%T)", respif), req.Id)
        }

        call.Otto.Set("ret_jsonrpc", shared.JsonRpcVersion)
        call.Otto.Set("ret_id", req.Id)

        var res []byte
        if isSuccessResponse {
            res, err = json.Marshal(sucres.Result)
        } else if isErrorResponse {
            res, err = json.Marshal(errres.Error)
        }

        call.Otto.Set("ret_result", string(res))
        call.Otto.Set("response_idx", i)
        response, err = call.Otto.Run(`
        ret_response[response_idx] = { jsonrpc: ret_jsonrpc, id: ret_id, result: JSON.parse(ret_result) };
        `)
    }

    if !batch {
        call.Otto.Run("ret_response = ret_response[0];")
    }

    if call.Argument(1).IsObject() {
        call.Otto.Set("callback", call.Argument(1))
        call.Otto.Run(`
        if (Object.prototype.toString.call(callback) == '[object Function]') {
            callback(null, ret_response);
        }
        `)
    }

    return
}

// handleRequest will handle user agent requests by interacting with the user and sending
// the user response back to the geth service
func (self *Jeth) handleRequest(req *shared.Request) bool {
    var err error
    var args []interface{}
    if err = json.Unmarshal(req.Params, &args); err != nil {
        glog.V(logger.Info).Infof("Unable to parse agent request - %v\n", err)
        return false
    }

    switch req.Method {
    case useragent.AskPasswordMethod:
        return self.askPassword(req.Id, req.Jsonrpc, args)
    case useragent.ConfirmTransactionMethod:
        return self.confirmTransaction(req.Id, req.Jsonrpc, args)
    }

    return false
}

// askPassword will ask the user to supply the password for a given account
func (self *Jeth) askPassword(id interface{}, jsonrpc string, args []interface{}) bool {
    var err error
    var passwd string
    if len(args) >= 1 {
        if account, ok := args[0].(string); ok {
            fmt.Printf("Unlock account %s\n", account)
            passwd, err = utils.PromptPassword("Passphrase: ", true)
        } else {
            return false
        }
    }

    if err = self.client.Send(shared.NewRpcResponse(id, jsonrpc, passwd, err)); err != nil {
        glog.V(logger.Info).Infof("Unable to send user agent ask password response - %v\n", err)
    }

    return err == nil
}

func (self *Jeth) confirmTransaction(id interface{}, jsonrpc string, args []interface{}) bool {
    // Accept all tx which are send from this console
    return self.client.Send(shared.NewRpcResponse(id, jsonrpc, true, nil)) == nil
}