书接上回，我们说Pyinstaller可能并不适合用来打包Scrapydweb，原因见构建Windows桌面版Scrapydweb （一）的结尾处。本文尝试借助python embeddable将python解释器、Scrapydweb及其依赖一并打包，再利用Electron构建成一个桌面APP。

下载python embeddable package

www.python.org/downloads/w...

这里我下载的是python 3.9.9 64-bit版。下载后直接解压即完成安装。为方便叙述，这里将解压后的根目录记为python_root。

安装Scrapydweb

安装pip

下载pip安装脚本，并用%python_root%/python.exe去执行该脚本。这样，pip等命令会被安装到%python_root%/Scripts目录下。

Warning! 按照上述方法安装的pip命令（即pip.exe）中含有python解释器路径的硬编码，这里即%python_root%/python.exe，当我们移动python embeddable的安装目录时，执行pip命令将因为找不到%python_root%/python.exe而报错。

安装Scrapyd、Scrapydweb

%python_root%/pip.exe install scrapyd scrapydweb

直接使用pip安装即可。依赖包会被安装在%python_root%/Lib/site-packages目录下。由于默认的包搜索路径不包含该目录，因此将该目录添加到%python_root%/python39_pth中，

Warning! 用pip安装的命令同样有上面所述的python解释器路径硬编码的问题。

创建Electron APP

npm init electron-app@latest my-app

编辑src/index.js，在其中启动scrapd和scrapydweb。

Note：

由于存在硬编码问题，所以这里改为用显式指定python去执行。
增加3秒后重新加载URL，尽量减少scrapdweb服务未启动完成而导致加载失败的可能。

最终src/index.js如下。

js 复制代码

const { app, BrowserWindow } = require('electron');
const path = require('node:path');

// Handle creating/removing shortcuts on Windows when installing/uninstalling.
if (require('electron-squirrel-startup')) {
  app.quit();
}

// python_root = scrapydweb-embed-python
const backendScrapyd = require('child_process').spawn('.\\python.exe' ,['.\\Lib\\site-packages\\scrapyd\\scripts\\scrapyd_run.py'],
{cwd: path.join(app.getPath('exe'), '../scrapydweb-embed-python')});

const backendScrapydweb = require('child_process').spawn('.\\python.exe' ,['.\\Lib\\site-packages\\scrapydweb\\run.py'],
{cwd: path.join(app.getPath('exe'), '../scrapydweb-embed-python')});

const createWindow = () => {
  // Create the browser window.
  const mainWindow = new BrowserWindow({
    width: 800,
    height: 600,
    webPreferences: {
      preload: path.join(__dirname, 'preload.js'),
    },
  });

  // and load the index.html of the app.
  // mainWindow.loadFile(path.join(__dirname, 'index.html'));
  mainWindow.loadURL('http://localhost:5000');

  mainWindow.webContents.on('did-fail-load', () => {
	setTimeout(() => {mainWindow.reload()}, 3000);
  });
  
  // Open the DevTools.
  // mainWindow.webContents.openDevTools();
};

// This method will be called when Electron has finished
// initialization and is ready to create browser windows.
// Some APIs can only be used after this event occurs.
app.whenReady().then(() => {
  createWindow();

  // On OS X it's common to re-create a window in the app when the
  // dock icon is clicked and there are no other windows open.
  app.on('activate', () => {
    if (BrowserWindow.getAllWindows().length === 0) {
      createWindow();
    }
  });
});

// Quit when all windows are closed, except on macOS. There, it's common
// for applications and their menu bar to stay active until the user quits
// explicitly with Cmd + Q.
app.on('window-all-closed', () => {
  
  if (process.platform !== 'darwin') {
    backendScrapydweb.kill();
    backendScrapyd.kill();
    app.quit();
  }
});

// In this file you can include the rest of your app's specific main process
// code. You can also put them in separate files and import them here.

打包Electron APP

npm run make

打包完成后，将out目录中的文件拷贝出来，作为整包的根目录，再将python_root拷贝到该根目录下，压缩即可。

最终整包的目录结构如下。其中，my-app.exe是执行入口。