path: root/cmd/geth/js.go

// Copyright 2014 The go-ethereum Authors
// This file is part of go-ethereum.
//
// go-ethereum 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 3 of the License, or
// (at your option) any later version.
//
// go-ethereum 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 go-ethereum.  If not, see <http://www.gnu.org/licenses/>.

package main

import (
    "bufio"
    "fmt"
    "math/big"
    "os"
    "os/signal"
    "path/filepath"
    "strings"

    "sort"

    "github.com/ethereum/go-ethereum/cmd/utils"
    "github.com/ethereum/go-ethereum/common"
    "github.com/ethereum/go-ethereum/common/docserver"
    "github.com/ethereum/go-ethereum/common/natspec"
    "github.com/ethereum/go-ethereum/common/registrar"
    "github.com/ethereum/go-ethereum/eth"
    re "github.com/ethereum/go-ethereum/jsre"
    "github.com/ethereum/go-ethereum/rpc"
    "github.com/ethereum/go-ethereum/rpc/api"
    "github.com/ethereum/go-ethereum/rpc/codec"
    "github.com/ethereum/go-ethereum/rpc/comms"
    "github.com/ethereum/go-ethereum/rpc/shared"
    "github.com/ethereum/go-ethereum/xeth"
    "github.com/peterh/liner"
    "github.com/robertkrimen/otto"
)

type prompter interface {
    AppendHistory(string)
    Prompt(p string) (string, error)
    PasswordPrompt(p string) (string, error)
}

type dumbterm struct{ r *bufio.Reader }

func (r dumbterm) Prompt(p string) (string, error) {
    fmt.Print(p)
    line, err := r.r.ReadString('\n')
    return strings.TrimSuffix(line, "\n"), err
}

func (r dumbterm) PasswordPrompt(p string) (string, error) {
    fmt.Println("!! Unsupported terminal, password will echo.")
    fmt.Print(p)
    input, err := bufio.NewReader(os.Stdin).ReadString('\n')
    fmt.Println()
    return input, err
}

func (r dumbterm) AppendHistory(string) {}

type jsre struct {
    ds         *docserver.DocServer
    re         *re.JSRE
    ethereum   *eth.Ethereum
    xeth       *xeth.XEth
    wait       chan *big.Int
    ps1        string
    atexit     func()
    corsDomain string
    client     comms.EthereumClient
    prompter
}

var (
    loadedModulesMethods map[string][]string
)

func keywordCompleter(line string) []string {
    results := make([]string, 0)

    if strings.Contains(line, ".") {
        elements := strings.Split(line, ".")
        if len(elements) == 2 {
            module := elements[0]
            partialMethod := elements[1]
            if methods, found := loadedModulesMethods[module]; found {
                for _, method := range methods {
                    if strings.HasPrefix(method, partialMethod) { // e.g. debug.se
                        results = append(results, module+"."+method)
                    }
                }
            }
        }
    } else {
        for module, methods := range loadedModulesMethods {
            if line == module { // user typed in full module name, show all methods
                for _, method := range methods {
                    results = append(results, module+"."+method)
                }
            } else if strings.HasPrefix(module, line) { // partial method name, e.g. admi
                results = append(results, module)
            }
        }
    }
    return results
}

func apiWordCompleter(line string, pos int) (head string, completions []string, tail string) {
    if len(line) == 0 {
        return "", nil, ""
    }

    i := 0
    for i = pos - 1; i > 0; i-- {
        if line[i] == '.' || (line[i] >= 'a' && line[i] <= 'z') || (line[i] >= 'A' && line[i] <= 'Z') {
            continue
        }
        if i >= 3 && line[i] == '3' && line[i-3] == 'w' && line[i-2] == 'e' && line[i-1] == 'b' {
            continue
        }
        i += 1
        break
    }

    begin := line[:i]
    keyword := line[i:pos]
    end := line[pos:]

    completionWords := keywordCompleter(keyword)
    return begin, completionWords, end
}

func newLightweightJSRE(libPath string, client comms.EthereumClient, interactive bool, f xeth.Frontend) *jsre {
    js := &jsre{ps1: "> "}
    js.wait = make(chan *big.Int)
    js.client = client
    js.ds = docserver.New("/")

    if f == nil {
        f = js
    }

    // update state in separare forever blocks
    js.re = re.New(libPath)
    if err := js.apiBindings(f); err != nil {
        utils.Fatalf("Unable to initialize console - %v", err)
    }

    if !liner.TerminalSupported() || !interactive {
        js.prompter = dumbterm{bufio.NewReader(os.Stdin)}
    } else {
        lr := liner.NewLiner()
        js.withHistory(func(hist *os.File) { lr.ReadHistory(hist) })
        lr.SetCtrlCAborts(true)
        js.loadAutoCompletion()
        lr.SetWordCompleter(apiWordCompleter)
        lr.SetTabCompletionStyle(liner.TabPrints)
        js.prompter = lr
        js.atexit = func() {
            js.withHistory(func(hist *os.File) { hist.Truncate(0); lr.WriteHistory(hist) })
            lr.Close()
            close(js.wait)
        }
    }
    return js
}

func newJSRE(ethereum *eth.Ethereum, libPath, corsDomain string, client comms.EthereumClient, interactive bool, f xeth.Frontend) *jsre {
    js := &jsre{ethereum: ethereum, ps1: "> "}
    // set default cors domain used by startRpc from CLI flag
    js.corsDomain = corsDomain
    if f == nil {
        f = js
    }
    js.ds = docserver.New("/")
    js.xeth = xeth.New(ethereum, f)
    js.wait = js.xeth.UpdateState()
    js.client = client
    if clt, ok := js.client.(*comms.InProcClient); ok {
        if offeredApis, err := api.ParseApiString(shared.AllApis, codec.JSON, js.xeth, ethereum); err == nil {
            clt.Initialize(api.Merge(offeredApis...))
        }
    }

    // update state in separare forever blocks
    js.re = re.New(libPath)
    if err := js.apiBindings(f); err != nil {
        utils.Fatalf("Unable to connect - %v", err)
    }

    if !liner.TerminalSupported() || !interactive {
        js.prompter = dumbterm{bufio.NewReader(os.Stdin)}
    } else {
        lr := liner.NewLiner()
        js.withHistory(func(hist *os.File) { lr.ReadHistory(hist) })
        lr.SetCtrlCAborts(true)
        js.loadAutoCompletion()
        lr.SetWordCompleter(apiWordCompleter)
        lr.SetTabCompletionStyle(liner.TabPrints)
        js.prompter = lr
        js.atexit = func() {
            js.withHistory(func(hist *os.File) { hist.Truncate(0); lr.WriteHistory(hist) })
            lr.Close()
            close(js.wait)
        }
    }
    return js
}

func (self *jsre) loadAutoCompletion() {
    if modules, err := self.supportedApis(); err == nil {
        loadedModulesMethods = make(map[string][]string)
        for module, _ := range modules {
            loadedModulesMethods[module] = api.AutoCompletion[module]
        }
    }
}

func (self *jsre) batch(statement string) {
    val, err := self.re.Run(statement)

    if err != nil {
        fmt.Printf("error: %v", err)
    } else if val.IsDefined() && val.IsObject() {
        obj, _ := self.re.Get("ret_result")
        fmt.Printf("%v", obj)
    } else if val.IsDefined() {
        fmt.Printf("%v", val)
    }

    if self.atexit != nil {
        self.atexit()
    }

    self.re.Stop(false)
}

// show summary of current geth instance
func (self *jsre) welcome() {
    self.re.Eval(`console.log('instance: ' + web3.version.client);`)
    self.re.Eval(`console.log(' datadir: ' + admin.datadir);`)
    self.re.Eval(`console.log("coinbase: " + eth.coinbase);`)
    self.re.Eval(`var lastBlockTimestamp = 1000 * eth.getBlock(eth.blockNumber).timestamp`)
    self.re.Eval(`console.log("at block: " + eth.blockNumber + " (" + new Date(lastBlockTimestamp).toLocaleDateString()
        + " " + new Date(lastBlockTimestamp).toLocaleTimeString() + ")");`)

    if modules, err := self.supportedApis(); err == nil {
        loadedModules := make([]string, 0)
        for api, version := range modules {
            loadedModules = append(loadedModules, fmt.Sprintf("%s:%s", api, version))
        }
        sort.Strings(loadedModules)

        self.re.Eval(fmt.Sprintf("var modules = '%s';", strings.Join(loadedModules, " ")))
        self.re.Eval(`console.log(" modules: " + modules);`)
    }
}

func (self *jsre) supportedApis() (map[string]string, error) {
    return self.client.SupportedModules()
}

func (js *jsre) apiBindings(f xeth.Frontend) error {
    apis, err := js.supportedApis()
    if err != nil {
        return err
    }

    apiNames := make([]string, 0, len(apis))
    for a, _ := range apis {
        apiNames = append(apiNames, a)
    }

    apiImpl, err := api.ParseApiString(strings.Join(apiNames, ","), codec.JSON, js.xeth, js.ethereum)
    if err != nil {
        utils.Fatalf("Unable to determine supported api's: %v", err)
    }

    jeth := rpc.NewJeth(api.Merge(apiImpl...), js.re, js.client)
    js.re.Set("jeth", struct{}{})
    t, _ := js.re.Get("jeth")
    jethObj := t.Object()

    jethObj.Set("send", jeth.Send)
    jethObj.Set("sendAsync", jeth.Send)

    err = js.re.Compile("bignumber.js", re.BigNumber_JS)
    if err != nil {
        utils.Fatalf("Error loading bignumber.js: %v", err)
    }

    err = js.re.Compile("ethereum.js", re.Web3_JS)
    if err != nil {
        utils.Fatalf("Error loading web3.js: %v", err)
    }

    _, err = js.re.Eval("var web3 = require('web3');")
    if err != nil {
        utils.Fatalf("Error requiring web3: %v", err)
    }

    _, err = js.re.Eval("web3.setProvider(jeth)")
    if err != nil {
        utils.Fatalf("Error setting web3 provider: %v", err)
    }

    // load only supported API's in javascript runtime
    shortcuts := "var eth = web3.eth; "
    for _, apiName := range apiNames {
        if apiName == shared.Web3ApiName {
            continue // manually mapped
        }

        if err = js.re.Compile(fmt.Sprintf("%s.js", apiName), api.Javascript(apiName)); err == nil {
            shortcuts += fmt.Sprintf("var %s = web3.%s; ", apiName, apiName)
        } else {
            utils.Fatalf("Error loading %s.js: %v", apiName, err)
        }
    }

    _, err = js.re.Eval(shortcuts)

    if err != nil {
        utils.Fatalf("Error setting namespaces: %v", err)
    }

    js.re.Eval(`var GlobalRegistrar = eth.contract(` + registrar.GlobalRegistrarAbi + `);    registrar = GlobalRegistrar.at("` + registrar.GlobalRegistrarAddr + `");`)
    return nil
}

func (self *jsre) ConfirmTransaction(tx string) bool {
    if self.ethereum.NatSpec {
        notice := natspec.GetNotice(self.xeth, tx, self.ds)
        fmt.Println(notice)
        answer, _ := self.Prompt("Confirm Transaction [y/n]")
        return strings.HasPrefix(strings.Trim(answer, " "), "y")
    } else {
        return true
    }
}

func (self *jsre) UnlockAccount(addr []byte) bool {
    fmt.Printf("Please unlock account %x.\n", addr)
    pass, err := self.PasswordPrompt("Passphrase: ")
    if err != nil {
        return false
    }
    // TODO: allow retry
    if err := self.ethereum.AccountManager().Unlock(common.BytesToAddress(addr), pass); err != nil {
        return false
    } else {
        fmt.Println("Account is now unlocked for this session.")
        return true
    }
}

func (self *jsre) exec(filename string) error {
    if err := self.re.Exec(filename); err != nil {
        self.re.Stop(false)
        return fmt.Errorf("Javascript Error: %v", err)
    }
    self.re.Stop(true)
    return nil
}

func (self *jsre) interactive() {
    // Read input lines.
    prompt := make(chan string)
    inputln := make(chan string)
    go func() {
        defer close(inputln)
        for {
            line, err := self.Prompt(<-prompt)
            if err != nil {
                return
            }
            inputln <- line
        }
    }()
    // Wait for Ctrl-C, too.
    sig := make(chan os.Signal, 1)
    signal.Notify(sig, os.Interrupt)

    defer func() {
        if self.atexit != nil {
            self.atexit()
        }
        self.re.Stop(false)
    }()
    for {
        prompt <- self.ps1
        select {
        case <-sig:
            fmt.Println("caught interrupt, exiting")
            return
        case input, ok := <-inputln:
            if !ok || indentCount <= 0 && input == "exit" {
                return
            }
            if input == "" {
                continue
            }
            str += input + "\n"
            self.setIndent()
            if indentCount <= 0 {
                hist := str[:len(str)-1]
                self.AppendHistory(hist)
                self.parseInput(str)
                str = ""
            }
        }
    }
}

func (self *jsre) withHistory(op func(*os.File)) {
    datadir := common.DefaultDataDir()
    if self.ethereum != nil {
        datadir = self.ethereum.DataDir
    }

    hist, err := os.OpenFile(filepath.Join(datadir, "history"), os.O_RDWR|os.O_CREATE, os.ModePerm)
    if err != nil {
        fmt.Printf("unable to open history file: %v\n", err)
        return
    }
    op(hist)
    hist.Close()
}

func (self *jsre) parseInput(code string) {
    defer func() {
        if r := recover(); r != nil {
            fmt.Println("[native] error", r)
        }
    }()
    value, err := self.re.Run(code)
    if err != nil {
        if ottoErr, ok := err.(*otto.Error); ok {
            fmt.Println(ottoErr.String())
        } else {
            fmt.Println(err)
        }
        return
    }
    self.printValue(value)
}

var indentCount = 0
var str = ""

func (self *jsre) setIndent() {
    open := strings.Count(str, "{")
    open += strings.Count(str, "(")
    closed := strings.Count(str, "}")
    closed += strings.Count(str, ")")
    indentCount = open - closed
    if indentCount <= 0 {
        self.ps1 = "> "
    } else {
        self.ps1 = strings.Join(make([]string, indentCount*2), "..")
        self.ps1 += " "
    }
}

func (self *jsre) printValue(v interface{}) {
    val, err := self.re.PrettyPrint(v)
    if err == nil {
        fmt.Printf("%v", val)
    }
}