plugeth/console/console.go
2022-05-16 11:59:35 +02:00

566 lines
18 KiB
Go

// Copyright 2016 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 console
import (
"errors"
"fmt"
"io"
"os"
"os/signal"
"path/filepath"
"regexp"
"sort"
"strings"
"sync"
"syscall"
"github.com/dop251/goja"
"github.com/ethereum/go-ethereum/console/prompt"
"github.com/ethereum/go-ethereum/internal/jsre"
"github.com/ethereum/go-ethereum/internal/jsre/deps"
"github.com/ethereum/go-ethereum/internal/web3ext"
"github.com/ethereum/go-ethereum/rpc"
"github.com/mattn/go-colorable"
"github.com/peterh/liner"
)
var (
// u: unlock, s: signXX, sendXX, n: newAccount, i: importXX
passwordRegexp = regexp.MustCompile(`personal.[nusi]`)
onlyWhitespace = regexp.MustCompile(`^\s*$`)
exit = regexp.MustCompile(`^\s*exit\s*;*\s*$`)
)
// HistoryFile is the file within the data directory to store input scrollback.
const HistoryFile = "history"
// DefaultPrompt is the default prompt line prefix to use for user input querying.
const DefaultPrompt = "> "
// Config is the collection of configurations to fine tune the behavior of the
// JavaScript console.
type Config struct {
DataDir string // Data directory to store the console history at
DocRoot string // Filesystem path from where to load JavaScript files from
Client *rpc.Client // RPC client to execute Ethereum requests through
Prompt string // Input prompt prefix string (defaults to DefaultPrompt)
Prompter prompt.UserPrompter // Input prompter to allow interactive user feedback (defaults to TerminalPrompter)
Printer io.Writer // Output writer to serialize any display strings to (defaults to os.Stdout)
Preload []string // Absolute paths to JavaScript files to preload
}
// Console is a JavaScript interpreted runtime environment. It is a fully fledged
// JavaScript console attached to a running node via an external or in-process RPC
// client.
type Console struct {
client *rpc.Client // RPC client to execute Ethereum requests through
jsre *jsre.JSRE // JavaScript runtime environment running the interpreter
prompt string // Input prompt prefix string
prompter prompt.UserPrompter // Input prompter to allow interactive user feedback
histPath string // Absolute path to the console scrollback history
history []string // Scroll history maintained by the console
printer io.Writer // Output writer to serialize any display strings to
interactiveStopped chan struct{}
stopInteractiveCh chan struct{}
signalReceived chan struct{}
stopped chan struct{}
wg sync.WaitGroup
stopOnce sync.Once
}
// New initializes a JavaScript interpreted runtime environment and sets defaults
// with the config struct.
func New(config Config) (*Console, error) {
// Handle unset config values gracefully
if config.Prompter == nil {
config.Prompter = prompt.Stdin
}
if config.Prompt == "" {
config.Prompt = DefaultPrompt
}
if config.Printer == nil {
config.Printer = colorable.NewColorableStdout()
}
// Initialize the console and return
console := &Console{
client: config.Client,
jsre: jsre.New(config.DocRoot, config.Printer),
prompt: config.Prompt,
prompter: config.Prompter,
printer: config.Printer,
histPath: filepath.Join(config.DataDir, HistoryFile),
interactiveStopped: make(chan struct{}),
stopInteractiveCh: make(chan struct{}),
signalReceived: make(chan struct{}, 1),
stopped: make(chan struct{}),
}
if err := os.MkdirAll(config.DataDir, 0700); err != nil {
return nil, err
}
if err := console.init(config.Preload); err != nil {
return nil, err
}
console.wg.Add(1)
go console.interruptHandler()
return console, nil
}
// init retrieves the available APIs from the remote RPC provider and initializes
// the console's JavaScript namespaces based on the exposed modules.
func (c *Console) init(preload []string) error {
c.initConsoleObject()
// Initialize the JavaScript <-> Go RPC bridge.
bridge := newBridge(c.client, c.prompter, c.printer)
if err := c.initWeb3(bridge); err != nil {
return err
}
if err := c.initExtensions(); err != nil {
return err
}
// Add bridge overrides for web3.js functionality.
c.jsre.Do(func(vm *goja.Runtime) {
c.initAdmin(vm, bridge)
c.initPersonal(vm, bridge)
})
// Preload JavaScript files.
for _, path := range preload {
if err := c.jsre.Exec(path); err != nil {
failure := err.Error()
if gojaErr, ok := err.(*goja.Exception); ok {
failure = gojaErr.String()
}
return fmt.Errorf("%s: %v", path, failure)
}
}
// Configure the input prompter for history and tab completion.
if c.prompter != nil {
if content, err := os.ReadFile(c.histPath); err != nil {
c.prompter.SetHistory(nil)
} else {
c.history = strings.Split(string(content), "\n")
c.prompter.SetHistory(c.history)
}
c.prompter.SetWordCompleter(c.AutoCompleteInput)
}
return nil
}
func (c *Console) initConsoleObject() {
c.jsre.Do(func(vm *goja.Runtime) {
console := vm.NewObject()
console.Set("log", c.consoleOutput)
console.Set("error", c.consoleOutput)
vm.Set("console", console)
})
}
func (c *Console) initWeb3(bridge *bridge) error {
if err := c.jsre.Compile("bignumber.js", deps.BigNumberJS); err != nil {
return fmt.Errorf("bignumber.js: %v", err)
}
if err := c.jsre.Compile("web3.js", deps.Web3JS); err != nil {
return fmt.Errorf("web3.js: %v", err)
}
if _, err := c.jsre.Run("var Web3 = require('web3');"); err != nil {
return fmt.Errorf("web3 require: %v", err)
}
var err error
c.jsre.Do(func(vm *goja.Runtime) {
transport := vm.NewObject()
transport.Set("send", jsre.MakeCallback(vm, bridge.Send))
transport.Set("sendAsync", jsre.MakeCallback(vm, bridge.Send))
vm.Set("_consoleWeb3Transport", transport)
_, err = vm.RunString("var web3 = new Web3(_consoleWeb3Transport)")
})
return err
}
// initExtensions loads and registers web3.js extensions.
func (c *Console) initExtensions() error {
// Compute aliases from server-provided modules.
apis, err := c.client.SupportedModules()
if err != nil {
return fmt.Errorf("api modules: %v", err)
}
aliases := map[string]struct{}{"eth": {}, "personal": {}}
for api := range apis {
if api == "web3" {
continue
}
aliases[api] = struct{}{}
if file, ok := web3ext.Modules[api]; ok {
if err = c.jsre.Compile(api+".js", file); err != nil {
return fmt.Errorf("%s.js: %v", api, err)
}
}
}
// Apply aliases.
c.jsre.Do(func(vm *goja.Runtime) {
web3 := getObject(vm, "web3")
for name := range aliases {
if v := web3.Get(name); v != nil {
vm.Set(name, v)
}
}
})
return nil
}
// initAdmin creates additional admin APIs implemented by the bridge.
func (c *Console) initAdmin(vm *goja.Runtime, bridge *bridge) {
if admin := getObject(vm, "admin"); admin != nil {
admin.Set("sleepBlocks", jsre.MakeCallback(vm, bridge.SleepBlocks))
admin.Set("sleep", jsre.MakeCallback(vm, bridge.Sleep))
admin.Set("clearHistory", c.clearHistory)
}
}
// initPersonal redirects account-related API methods through the bridge.
//
// If the console is in interactive mode and the 'personal' API is available, override
// the openWallet, unlockAccount, newAccount and sign methods since these require user
// interaction. The original web3 callbacks are stored in 'jeth'. These will be called
// by the bridge after the prompt and send the original web3 request to the backend.
func (c *Console) initPersonal(vm *goja.Runtime, bridge *bridge) {
personal := getObject(vm, "personal")
if personal == nil || c.prompter == nil {
return
}
jeth := vm.NewObject()
vm.Set("jeth", jeth)
jeth.Set("openWallet", personal.Get("openWallet"))
jeth.Set("unlockAccount", personal.Get("unlockAccount"))
jeth.Set("newAccount", personal.Get("newAccount"))
jeth.Set("sign", personal.Get("sign"))
personal.Set("openWallet", jsre.MakeCallback(vm, bridge.OpenWallet))
personal.Set("unlockAccount", jsre.MakeCallback(vm, bridge.UnlockAccount))
personal.Set("newAccount", jsre.MakeCallback(vm, bridge.NewAccount))
personal.Set("sign", jsre.MakeCallback(vm, bridge.Sign))
}
func (c *Console) clearHistory() {
c.history = nil
c.prompter.ClearHistory()
if err := os.Remove(c.histPath); err != nil {
fmt.Fprintln(c.printer, "can't delete history file:", err)
} else {
fmt.Fprintln(c.printer, "history file deleted")
}
}
// consoleOutput is an override for the console.log and console.error methods to
// stream the output into the configured output stream instead of stdout.
func (c *Console) consoleOutput(call goja.FunctionCall) goja.Value {
var output []string
for _, argument := range call.Arguments {
output = append(output, fmt.Sprintf("%v", argument))
}
fmt.Fprintln(c.printer, strings.Join(output, " "))
return goja.Null()
}
// AutoCompleteInput is a pre-assembled word completer to be used by the user
// input prompter to provide hints to the user about the methods available.
func (c *Console) AutoCompleteInput(line string, pos int) (string, []string, string) {
// No completions can be provided for empty inputs
if len(line) == 0 || pos == 0 {
return "", nil, ""
}
// Chunck data to relevant part for autocompletion
// E.g. in case of nested lines eth.getBalance(eth.coinb<tab><tab>
start := pos - 1
for ; start > 0; start-- {
// Skip all methods and namespaces (i.e. including the dot)
if line[start] == '.' || (line[start] >= 'a' && line[start] <= 'z') || (line[start] >= 'A' && line[start] <= 'Z') {
continue
}
// Handle web3 in a special way (i.e. other numbers aren't auto completed)
if start >= 3 && line[start-3:start] == "web3" {
start -= 3
continue
}
// We've hit an unexpected character, autocomplete form here
start++
break
}
return line[:start], c.jsre.CompleteKeywords(line[start:pos]), line[pos:]
}
// Welcome show summary of current Geth instance and some metadata about the
// console's available modules.
func (c *Console) Welcome() {
message := "Welcome to the Geth JavaScript console!\n\n"
// Print some generic Geth metadata
if res, err := c.jsre.Run(`
var message = "instance: " + web3.version.node + "\n";
try {
message += "coinbase: " + eth.coinbase + "\n";
} catch (err) {}
message += "at block: " + eth.blockNumber + " (" + new Date(1000 * eth.getBlock(eth.blockNumber).timestamp) + ")\n";
try {
message += " datadir: " + admin.datadir + "\n";
} catch (err) {}
message
`); err == nil {
message += res.String()
}
// List all the supported modules for the user to call
if apis, err := c.client.SupportedModules(); err == nil {
modules := make([]string, 0, len(apis))
for api, version := range apis {
modules = append(modules, fmt.Sprintf("%s:%s", api, version))
}
sort.Strings(modules)
message += " modules: " + strings.Join(modules, " ") + "\n"
}
message += "\nTo exit, press ctrl-d or type exit"
fmt.Fprintln(c.printer, message)
}
// Evaluate executes code and pretty prints the result to the specified output
// stream.
func (c *Console) Evaluate(statement string) {
defer func() {
if r := recover(); r != nil {
fmt.Fprintf(c.printer, "[native] error: %v\n", r)
}
}()
c.jsre.Evaluate(statement, c.printer)
// Avoid exiting Interactive when jsre was interrupted by SIGINT.
c.clearSignalReceived()
}
// interruptHandler runs in its own goroutine and waits for signals.
// When a signal is received, it interrupts the JS interpreter.
func (c *Console) interruptHandler() {
defer c.wg.Done()
// During Interactive, liner inhibits the signal while it is prompting for
// input. However, the signal will be received while evaluating JS.
//
// On unsupported terminals, SIGINT can also happen while prompting.
// Unfortunately, it is not possible to abort the prompt in this case and
// the c.readLines goroutine leaks.
sig := make(chan os.Signal, 1)
signal.Notify(sig, syscall.SIGINT)
defer signal.Stop(sig)
for {
select {
case <-sig:
c.setSignalReceived()
c.jsre.Interrupt(errors.New("interrupted"))
case <-c.stopInteractiveCh:
close(c.interactiveStopped)
c.jsre.Interrupt(errors.New("interrupted"))
case <-c.stopped:
return
}
}
}
func (c *Console) setSignalReceived() {
select {
case c.signalReceived <- struct{}{}:
default:
}
}
func (c *Console) clearSignalReceived() {
select {
case <-c.signalReceived:
default:
}
}
// StopInteractive causes Interactive to return as soon as possible.
func (c *Console) StopInteractive() {
select {
case c.stopInteractiveCh <- struct{}{}:
case <-c.stopped:
}
}
// Interactive starts an interactive user session, where in.put is propted from
// the configured user prompter.
func (c *Console) Interactive() {
var (
prompt = c.prompt // the current prompt line (used for multi-line inputs)
indents = 0 // the current number of input indents (used for multi-line inputs)
input = "" // the current user input
inputLine = make(chan string, 1) // receives user input
inputErr = make(chan error, 1) // receives liner errors
requestLine = make(chan string) // requests a line of input
)
defer func() {
c.writeHistory()
}()
// The line reader runs in a separate goroutine.
go c.readLines(inputLine, inputErr, requestLine)
defer close(requestLine)
for {
// Send the next prompt, triggering an input read.
requestLine <- prompt
select {
case <-c.interactiveStopped:
fmt.Fprintln(c.printer, "node is down, exiting console")
return
case <-c.signalReceived:
// SIGINT received while prompting for input -> unsupported terminal.
// I'm not sure if the best choice would be to leave the console running here.
// Bash keeps running in this case. node.js does not.
fmt.Fprintln(c.printer, "caught interrupt, exiting")
return
case err := <-inputErr:
if err == liner.ErrPromptAborted {
// When prompting for multi-line input, the first Ctrl-C resets
// the multi-line state.
prompt, indents, input = c.prompt, 0, ""
continue
}
return
case line := <-inputLine:
// User input was returned by the prompter, handle special cases.
if indents <= 0 && exit.MatchString(line) {
return
}
if onlyWhitespace.MatchString(line) {
continue
}
// Append the line to the input and check for multi-line interpretation.
input += line + "\n"
indents = countIndents(input)
if indents <= 0 {
prompt = c.prompt
} else {
prompt = strings.Repeat(".", indents*3) + " "
}
// If all the needed lines are present, save the command and run it.
if indents <= 0 {
if len(input) > 0 && input[0] != ' ' && !passwordRegexp.MatchString(input) {
if command := strings.TrimSpace(input); len(c.history) == 0 || command != c.history[len(c.history)-1] {
c.history = append(c.history, command)
if c.prompter != nil {
c.prompter.AppendHistory(command)
}
}
}
c.Evaluate(input)
input = ""
}
}
}
}
// readLines runs in its own goroutine, prompting for input.
func (c *Console) readLines(input chan<- string, errc chan<- error, prompt <-chan string) {
for p := range prompt {
line, err := c.prompter.PromptInput(p)
if err != nil {
errc <- err
} else {
input <- line
}
}
}
// countIndents returns the number of identations for the given input.
// In case of invalid input such as var a = } the result can be negative.
func countIndents(input string) int {
var (
indents = 0
inString = false
strOpenChar = ' ' // keep track of the string open char to allow var str = "I'm ....";
charEscaped = false // keep track if the previous char was the '\' char, allow var str = "abc\"def";
)
for _, c := range input {
switch c {
case '\\':
// indicate next char as escaped when in string and previous char isn't escaping this backslash
if !charEscaped && inString {
charEscaped = true
}
case '\'', '"':
if inString && !charEscaped && strOpenChar == c { // end string
inString = false
} else if !inString && !charEscaped { // begin string
inString = true
strOpenChar = c
}
charEscaped = false
case '{', '(':
if !inString { // ignore brackets when in string, allow var str = "a{"; without indenting
indents++
}
charEscaped = false
case '}', ')':
if !inString {
indents--
}
charEscaped = false
default:
charEscaped = false
}
}
return indents
}
// Execute runs the JavaScript file specified as the argument.
func (c *Console) Execute(path string) error {
return c.jsre.Exec(path)
}
// Stop cleans up the console and terminates the runtime environment.
func (c *Console) Stop(graceful bool) error {
c.stopOnce.Do(func() {
// Stop the interrupt handler.
close(c.stopped)
c.wg.Wait()
})
c.jsre.Stop(graceful)
return nil
}
func (c *Console) writeHistory() error {
if err := os.WriteFile(c.histPath, []byte(strings.Join(c.history, "\n")), 0600); err != nil {
return err
}
return os.Chmod(c.histPath, 0600) // Force 0600, even if it was different previously
}