path: root/cmd/ethereum/repl/repl.go

// Copyright (c) 2013-2014, Jeffrey Wilcke. All rights reserved.
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
//
// This 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
// General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this library; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
// MA 02110-1301  USA

package ethrepl

import (
    "bufio"
    "fmt"
    "io"
    "os"
    "path"

    "github.com/ethereum/go-ethereum/core/types"
    "github.com/ethereum/go-ethereum/eth"
    "github.com/ethereum/go-ethereum/ethutil"
    "github.com/ethereum/go-ethereum/javascript"
    "github.com/ethereum/go-ethereum/logger"
    "github.com/ethereum/go-ethereum/state"
    "github.com/ethereum/go-ethereum/xeth"
    "github.com/obscuren/otto"
)

var repllogger = logger.NewLogger("REPL")

type Repl interface {
    Start()
    Stop()
}

type JSRepl struct {
    re       *javascript.JSRE
    ethereum *eth.Ethereum
    xeth     *xeth.XEth

    prompt string

    history *os.File

    running bool
}

func NewJSRepl(ethereum *eth.Ethereum) *JSRepl {
    hist, err := os.OpenFile(path.Join(ethutil.Config.ExecPath, "history"), os.O_RDWR|os.O_CREATE, os.ModePerm)
    if err != nil {
        panic(err)
    }

    xeth := xeth.New(ethereum)
    repl := &JSRepl{re: javascript.NewJSRE(xeth), xeth: xeth, ethereum: ethereum, prompt: "> ", history: hist}
    repl.initStdFuncs()

    return repl
}

func (self *JSRepl) Start() {
    if !self.running {
        self.running = true
        repllogger.Infoln("init JS Console")

        reader := bufio.NewReader(self.history)
        for {
            line, err := reader.ReadString('\n')
            if err != nil && err == io.EOF {
                break
            } else if err != nil {
                fmt.Println("error reading history", err)
                break
            }

            addHistory(line[:len(line)-1])
        }
        self.read()
    }
}

func (self *JSRepl) Stop() {
    if self.running {
        self.running = false
        repllogger.Infoln("exit JS Console")
        self.history.Close()
    }
}

func (self *JSRepl) parseInput(code string) {
    defer func() {
        if r := recover(); r != nil {
            fmt.Println("[native] error", r)
        }
    }()

    value, err := self.re.Run(code)
    if err != nil {
        fmt.Println(err)
        return
    }

    self.PrintValue(value)
}

func (self *JSRepl) initStdFuncs() {
    t, _ := self.re.Vm.Get("eth")
    eth := t.Object()
    eth.Set("connect", self.connect)
    eth.Set("stopMining", self.stopMining)
    eth.Set("startMining", self.startMining)
    eth.Set("dump", self.dump)
    eth.Set("export", self.export)
}

/*
 * The following methods are natively implemented javascript functions
 */

func (self *JSRepl) dump(call otto.FunctionCall) otto.Value {
    var block *types.Block

    if len(call.ArgumentList) > 0 {
        if call.Argument(0).IsNumber() {
            num, _ := call.Argument(0).ToInteger()
            block = self.ethereum.ChainManager().GetBlockByNumber(uint64(num))
        } else if call.Argument(0).IsString() {
            hash, _ := call.Argument(0).ToString()
            block = self.ethereum.ChainManager().GetBlock(ethutil.Hex2Bytes(hash))
        } else {
            fmt.Println("invalid argument for dump. Either hex string or number")
        }

        if block == nil {
            fmt.Println("block not found")

            return otto.UndefinedValue()
        }

    } else {
        block = self.ethereum.ChainManager().CurrentBlock()
    }

    statedb := state.New(block.Root(), self.ethereum.Db())

    v, _ := self.re.Vm.ToValue(statedb.RawDump())

    return v
}

func (self *JSRepl) stopMining(call otto.FunctionCall) otto.Value {
    self.xeth.Miner().Stop()

    return otto.TrueValue()
}

func (self *JSRepl) startMining(call otto.FunctionCall) otto.Value {
    self.xeth.Miner().Start()
    return otto.TrueValue()
}

func (self *JSRepl) connect(call otto.FunctionCall) otto.Value {
    nodeURL, err := call.Argument(0).ToString()
    if err != nil {
        return otto.FalseValue()
    }
    if err := self.ethereum.SuggestPeer(nodeURL); err != nil {
        return otto.FalseValue()
    }
    return otto.TrueValue()
}

func (self *JSRepl) export(call otto.FunctionCall) otto.Value {
    if len(call.ArgumentList) == 0 {
        fmt.Println("err: require file name")
        return otto.FalseValue()
    }

    fn, err := call.Argument(0).ToString()
    if err != nil {
        fmt.Println(err)
        return otto.FalseValue()
    }

    data := self.ethereum.ChainManager().Export()

    if err := ethutil.WriteFile(fn, data); err != nil {
        fmt.Println(err)
        return otto.FalseValue()
    }

    return otto.TrueValue()
}