Puppeteer - 协议错误（Page.captureScreenshot）：当我尝试截屏时目标关闭

Question

我正在运行这个示例代码：

async takeScreenshot() {  
        console.log('trying take Screenshot [...]');
        let image = this.page.screenshot({fullPage: true, type: 'jpeg'});
        timeout(image, 30000)
        .then((thing) => console.log("screenshot successfull!"))
        .catch((err) => {
            if(err instanceof TimeoutError) {
                console.log(err);
                image = null;
            }
        })

        console.log('Completed!');
        return image;
    }

我收到以下错误输出：

0|时代监视器 |错误：协议错误（Page.captureScreenshot）：目标已关闭。 0|时代监视器|在 Session._onClosed (/home/ubuntu/project/ra-monitors/era-monitor-browser/node_modules/puppeteer/lib/Connection.js:209:23) 0|时代监视器|在 Connection._onClose (/home/ubuntu/project/ra-monitors/era-monitor-browser/node_modules/puppeteer/lib/Connection.js:116:15) 0|时代监视器|在 emitTwo (events.js:106:13) 0|时代监视器|在 WebSocket.emit (events.js:194:7) 0|时代监视器|在 WebSocket.emitClose (/home/ubuntu/project/ra-monitors/era-monitor-browser/node_modules/ws/lib/WebSocket.js:213:10) 0|时代监视器|在 _receiver.cleanup (/home/ubuntu/project/ra-monitors/era-monitor-browser/node_modules/ws/lib/WebSocket.js:195:41) 0|时代监视器|在 Receiver.cleanup (/home/ubuntu/project/ra-monitors/era-monitor-browser/node_modules/ws/lib/Receiver.js:520:15) 0|时代监视器|在 WebSocket.finalize (/home/ubuntu/project/ra-monitors/era-monitor-browser/node_modules/ws/lib/WebSocket.js:195:22) 0|时代监视器|在 emitNone (events.js:91:20) 0|时代监视器|在 Socket.emit (events.js:188:7)

Answer 1

你需要在page.screenshot()之前使用await运算符，因为该函数是异步的：

let image = await this.page.screenshot({
  fullPage: true,
  type: 'jpeg',
});