Fantom-foundation/go-lachesis

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cmd/lachesis/consolecmd.go

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// 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 main

import (
    "fmt"
    "os"
    "os/signal"
    "path/filepath"
    "strings"
    "syscall"

    "github.com/ethereum/go-ethereum/cmd/utils"
    "github.com/ethereum/go-ethereum/console"
    "github.com/ethereum/go-ethereum/node"
    "github.com/ethereum/go-ethereum/rpc"
    "gopkg.in/urfave/cli.v1"
)

var (
    consoleFlags = []cli.Flag{utils.JSpathFlag, utils.ExecFlag, utils.PreloadJSFlag}

    consoleCommand = cli.Command{
        Action:   utils.MigrateFlags(localConsole),
        Name:     "console",
        Usage:    "Start an interactive JavaScript environment",
        Flags:    append(append(append(nodeFlags, rpcFlags...), consoleFlags...), testFlags...),
        Category: "CONSOLE COMMANDS",
        Description: `
The lachesis console is an interactive shell for the JavaScript runtime environment
which exposes a node admin interface as well as the Ðapp JavaScript API.
See https://github.com/ethereum/go-ethereum/wiki/JavaScript-Console.`,
    }

    attachCommand = cli.Command{
        Action:    utils.MigrateFlags(remoteConsole),
        Name:      "attach",
        Usage:     "Start an interactive JavaScript environment (connect to node)",
        ArgsUsage: "[endpoint]",
        Flags:     append(consoleFlags, utils.DataDirFlag),
        Category:  "CONSOLE COMMANDS",
        Description: `
The lachesis console is an interactive shell for the JavaScript runtime environment
which exposes a node admin interface as well as the Ðapp JavaScript API.
See https://github.com/ethereum/go-ethereum/wiki/JavaScript-Console.
This command allows to open a console on a running lachesis node.`,
    }

    javascriptCommand = cli.Command{
        Action:    utils.MigrateFlags(ephemeralConsole),
        Name:      "js",
        Usage:     "Execute the specified JavaScript files",
        ArgsUsage: "<jsfile> [jsfile...]",
        Flags:     append(append(nodeFlags, consoleFlags...), testFlags...),
        Category:  "CONSOLE COMMANDS",
        Description: `
The JavaScript VM exposes a node admin interface as well as the Ðapp
JavaScript API. See https://github.com/ethereum/go-ethereum/wiki/JavaScript-Console`,
    }
)

// localConsole starts a new lachesis node, attaching a JavaScript console to it at the
// same time.
func localConsole(ctx *cli.Context) error {
    // Create and start the node based on the CLI flags
    node, _ := makeNode(ctx, makeAllConfigs(ctx))
    startNode(ctx, node)
    defer node.Close()

    // Attach to the newly started node and start the JavaScript console
    client, err := node.Attach()
    if err != nil {
        utils.Fatalf("Failed to attach to the inproc lachesis: %v", err)
    }
    config := console.Config{
        DataDir: utils.MakeDataDir(ctx),
        DocRoot: ctx.GlobalString(utils.JSpathFlag.Name),
        Client:  client,
        Preload: utils.MakeConsolePreloads(ctx),
    }

    console, err := console.New(config)
    if err != nil {
        utils.Fatalf("Failed to start the JavaScript console: %v", err)
    }
    defer console.Stop(false)

    // If only a short execution was requested, evaluate and return
    if script := ctx.GlobalString(utils.ExecFlag.Name); script != "" {
        console.Evaluate(script)
        return nil
    }
    // Otherwise print the welcome screen and enter interactive mode
    console.Welcome()
    console.Interactive()

    return nil
}

// remoteConsole will connect to a remote lachesis instance, attaching a JavaScript
// console to it.
func remoteConsole(ctx *cli.Context) error {
    // Attach to a remotely running lachesis instance and start the JavaScript console
    endpoint := ctx.Args().First()
    if endpoint == "" {
        path := DefaultDataDir()
        if ctx.GlobalIsSet(utils.DataDirFlag.Name) {
            path = ctx.GlobalString(utils.DataDirFlag.Name)
        }
        if path != "" {
            if ctx.GlobalBool(utils.LegacyTestnetFlag.Name) {
                path = filepath.Join(path, "testnet")
            } else if ctx.GlobalBool(utils.RinkebyFlag.Name) {
                path = filepath.Join(path, "rinkeby")
            }
        }
        endpoint = fmt.Sprintf("%s/lachesis.ipc", path)
    }
    client, err := dialRPC(endpoint)
    if err != nil {
        utils.Fatalf("Unable to attach to remote lachesis: %v", err)
    }
    config := console.Config{
        DataDir: utils.MakeDataDir(ctx),
        DocRoot: ctx.GlobalString(utils.JSpathFlag.Name),
        Client:  client,
        Preload: utils.MakeConsolePreloads(ctx),
    }

    console, err := console.New(config)
    if err != nil {
        utils.Fatalf("Failed to start the JavaScript console: %v", err)
    }
    defer console.Stop(false)

    if script := ctx.GlobalString(utils.ExecFlag.Name); script != "" {
        console.Evaluate(script)
        return nil
    }

    // Otherwise print the welcome screen and enter interactive mode
    console.Welcome()
    console.Interactive()

    return nil
}

// dialRPC returns a RPC client which connects to the given endpoint.
// The check for empty endpoint implements the defaulting logic
// for "lachesis attach" and "lachesis monitor" with no argument.
func dialRPC(endpoint string) (*rpc.Client, error) {
    if endpoint == "" {
        endpoint = node.DefaultIPCEndpoint(clientIdentifier)
    } else if strings.HasPrefix(endpoint, "rpc:") || strings.HasPrefix(endpoint, "ipc:") {
        // Backwards compatibility with rpc which required these prefixes.
        endpoint = endpoint[4:]
    }
    return rpc.Dial(endpoint)
}

// ephemeralConsole starts a new lachesis node, attaches an ephemeral JavaScript
// console to it, executes each of the files specified as arguments and tears
// everything down.
func ephemeralConsole(ctx *cli.Context) error {
    // Create and start the node based on the CLI flags
    node, _ := makeNode(ctx, makeAllConfigs(ctx))
    startNode(ctx, node)
    defer node.Close()

    // Attach to the newly started node and start the JavaScript console
    client, err := node.Attach()
    if err != nil {
        utils.Fatalf("Failed to attach to the inproc lachesis: %v", err)
    }
    config := console.Config{
        DataDir: utils.MakeDataDir(ctx),
        DocRoot: ctx.GlobalString(utils.JSpathFlag.Name),
        Client:  client,
        Preload: utils.MakeConsolePreloads(ctx),
    }

    console, err := console.New(config)
    if err != nil {
        utils.Fatalf("Failed to start the JavaScript console: %v", err)
    }
    defer console.Stop(false)

    // Evaluate each of the specified JavaScript files
    for _, file := range ctx.Args() {
        if err = console.Execute(file); err != nil {
            utils.Fatalf("Failed to execute %s: %v", file, err)
        }
    }
    // Wait for pending callbacks, but stop for Ctrl-C.
    abort := make(chan os.Signal, 1)
    signal.Notify(abort, syscall.SIGINT, syscall.SIGTERM)

    go func() {
        <-abort
        os.Exit(0)
    }()
    console.Stop(true)

    return nil
}