electron/default_app/main.js

const {app, dialog, shell, Menu} = require('electron')

const fs = require('fs')
const Module = require('module')
const path = require('path')
const url = require('url')

// Parse command line options.
const argv = process.argv.slice(1)

const option = {
  file: null,
  help: null,
  default: null,
  version: null,
  webdriver: null,
  modules: []
}

for (let i = 0; i < argv.length; i++) {
  if (argv[i] === '--version' || argv[i] === '-v') {
    option.version = true
    break
  } else if (argv[i].match(/^--app=/)) {
    option.file = argv[i].split('=')[1]
    break
  } else if (argv[i] === '--default' || argv[i] === '-d') {
    option.default = true
    break
  } else if (argv[i] === '--interactive' || argv[i] === '-i' ||
    argv[i] === '-repl' || argv[i] === '-r') {
    option.interactive = true
  } else if (argv[i] === '--test-type=webdriver') {
    option.webdriver = true
  } else if (argv[i] === '--require' || argv[i] === '-r') {
    option.modules.push(argv[++i])
    continue
  } else if (argv[i][0] === '-') {
    continue
  } else {
    option.file = argv[i]
    break
  }
}

// Quit when all windows are closed and no other one is listening to this.
app.on('window-all-closed', () => {
  if (app.listeners('window-all-closed').length === 1 && !option.interactive) {
    app.quit()
  }
})

// Create default menu.
app.once('ready', () => {
  if (Menu.getApplicationMenu()) return

  const template = [
    {
      label: 'Edit',
      submenu: [
        {
          role: 'undo'
        },
        {
          role: 'redo'
        },
        {
          type: 'separator'
        },
        {
          role: 'cut'
        },
        {
          role: 'copy'
        },
        {
          role: 'paste'
        },
        {
          role: 'pasteandmatchstyle'
        },
        {
          role: 'delete'
        },
        {
          role: 'selectall'
        }
      ]
    },
    {
      label: 'View',
      submenu: [
        {
          role: 'reload'
        },
        {
          role: 'forcereload'
        },
        {
          role: 'toggledevtools'
        },
        {
          type: 'separator'
        },
        {
          role: 'resetzoom'
        },
        {
          role: 'zoomin'
        },
        {
          role: 'zoomout'
        },
        {
          type: 'separator'
        },
        {
          role: 'togglefullscreen'
        }
      ]
    },
    {
      role: 'window',
      submenu: [
        {
          role: 'minimize'
        },
        {
          role: 'close'
        }
      ]
    },
    {
      role: 'help',
      submenu: [
        {
          label: 'Learn More',
          click () {
            shell.openExternal('https://electron.atom.io')
          }
        },
        {
          label: 'Documentation',
          click () {
            shell.openExternal(
              `https://github.com/electron/electron/tree/v${process.versions.electron}/docs#readme`
            )
          }
        },
        {
          label: 'Community Discussions',
          click () {
            shell.openExternal('https://discuss.atom.io/c/electron')
          }
        },
        {
          label: 'Search Issues',
          click () {
            shell.openExternal('https://github.com/electron/electron/issues')
          }
        }
      ]
    }
  ]

  if (process.platform === 'darwin') {
    template.unshift({
      label: 'Electron',
      submenu: [
        {
          role: 'about'
        },
        {
          type: 'separator'
        },
        {
          role: 'services',
          submenu: []
        },
        {
          type: 'separator'
        },
        {
          role: 'hide'
        },
        {
          role: 'hideothers'
        },
        {
          role: 'unhide'
        },
        {
          type: 'separator'
        },
        {
          role: 'quit'
        }
      ]
    })
    template[1].submenu.push({
      type: 'separator'
    }, {
      label: 'Speech',
      submenu: [
        {
          role: 'startspeaking'
        },
        {
          role: 'stopspeaking'
        }
      ]
    })
    template[3].submenu = [
      {
        role: 'close'
      },
      {
        role: 'minimize'
      },
      {
        role: 'zoom'
      },
      {
        type: 'separator'
      },
      {
        role: 'front'
      }
    ]
  } else {
    template.unshift({
      label: 'File',
      submenu: [{
        role: 'quit'
      }]
    })
  }

  const menu = Menu.buildFromTemplate(template)
  Menu.setApplicationMenu(menu)
})

if (option.modules.length > 0) {
  Module._preloadModules(option.modules)
}

function loadApplicationPackage (packagePath) {
  // Add a flag indicating app is started from default app.
  process.defaultApp = true

  try {
    // Override app name and version.
    packagePath = path.resolve(packagePath)
    const packageJsonPath = path.join(packagePath, 'package.json')
    if (fs.existsSync(packageJsonPath)) {
      let packageJson
      try {
        packageJson = require(packageJsonPath)
      } catch (e) {
        showErrorMessage(`Unable to parse ${packageJsonPath}\n\n${e.message}`)
        return
      }

      if (packageJson.version) {
        app.setVersion(packageJson.version)
      }
      if (packageJson.productName) {
        app.setName(packageJson.productName)
      } else if (packageJson.name) {
        app.setName(packageJson.name)
      }
      app.setPath('userData', path.join(app.getPath('appData'), app.getName()))
      app.setPath('userCache', path.join(app.getPath('cache'), app.getName()))
      app.setAppPath(packagePath)
    }

    try {
      Module._resolveFilename(packagePath, module, true)
    } catch (e) {
      showErrorMessage(`Unable to find Electron app at ${packagePath}\n\n${e.message}`)
      return
    }

    // Run the app.
    Module._load(packagePath, module, true)
  } catch (e) {
    console.error('App threw an error during load')
    console.error(e.stack || e)
    throw e
  }
}

function showErrorMessage (message) {
  app.focus()
  dialog.showErrorBox('Error launching app', message)
  process.exit(1)
}

function loadApplicationByUrl (appUrl) {
  require('./default_app').load(appUrl)
}

function startRepl () {
  if (process.platform === 'win32') {
    console.error('Electron REPL not currently supported on Windows')
    process.exit(1)
    return
  }

  const repl = require('repl')
  repl.start('> ').on('exit', () => {
    process.exit(0)
  })
}

// Start the specified app if there is one specified in command line, otherwise
// start the default app.
if (option.file && !option.webdriver) {
  const file = option.file
  const protocol = url.parse(file).protocol
  const extension = path.extname(file)
  if (protocol === 'http:' || protocol === 'https:' || protocol === 'file:') {
    loadApplicationByUrl(file)
  } else if (extension === '.html' || extension === '.htm') {
    loadApplicationByUrl('file://' + path.resolve(file))
  } else {
    loadApplicationPackage(file)
  }
} else if (option.version) {
  console.log('v' + process.versions.electron)
  process.exit(0)
} else if (option.default) {
  const indexPath = path.join(__dirname, '/index.html')
  loadApplicationByUrl(`file://${indexPath}`)
} else if (option.interactive) {
  startRepl()
} else {
  const welcomeMessage = `Electron ${process.versions.electron} - Build cross platform desktop apps with JavaScript, HTML, and CSS

  Usage: electron [options] [path]

  A path to an Electron app may be specified. It must be one of the following:
    - index.js file.
    - Folder containing a package.json file.
    - Folder containing an index.js file.
    - .html/.htm file.
    - http://, https://, or file:// URL.

  Options:
    -d, --default         Run the default bundled Electron app.
    -i, --interactive     Open a REPL to the main process.
    -r, --require         Module to preload (option can be repeated)
    -v, --version         Print the version.`
  console.log(welcomeMessage)
  process.exit(0)
}