需求場(chǎng)景

獲取網(wǎng)站點(diǎn)擊的下載pdf，并把pdf重命名再上傳到COS云上面

技術(shù)使用

“puppeteer”: “^19.7.2”,
“egg”: “^3.15.0”, // 服務(wù)期用egg搭的
文件服務(wù)使用COS騰訊云

核心思路

獲取瀏覽器下載事件，并把文件保存到本地

const session = await substitutePage.target()
      .createCDPSession();
    await session.send('Page.setDownloadBehavior', {
      behavior: 'allow',
      downloadPath, // 指定文件保存路徑回家
    });

在保存到本地前監(jiān)聽此文件夾，如果有文件則獲取并上傳
加timer做防抖是為了防止在文件寫入時(shí)以及重命名文件時(shí)多次觸發(fā)watch函數(shù)，導(dǎo)致出會(huì)出現(xiàn)0KB源文件臟數(shù)據(jù)

 let timer: any = null;
 fs.watch(downloadPath, async (_eventType, filename) => {
 if (timer !== null) {
 clearTimeout(timer);
   }
   timer = setTimeout(() => {
     // 防止出現(xiàn)下載的臨時(shí)文件就觸發(fā)
     if (filename.endsWith('.pdf')) {
       resolve({
         filename,
       });
     }
   }, 500);
 });

完整代碼

    const session = await substitutePage.target()
      .createCDPSession();
    await session.send('Page.setDownloadBehavior', {
      behavior: 'allow',
      downloadPath, // 指定文件保存路徑回家
    });
     // res就是文件相關(guān)信息了
    const [ res ] = await this.downloadPdfHandler(substitutePage, downloadPath);
    // filePath就是自己本地的文件所在絕對(duì)路徑
    const filePath = `${downloadPath}/${res.fileName}`;
    // uploadFile是cos文件上傳相關(guān)實(shí)現(xiàn)， 我就不放了，有私密的key
    const pdfUriCode = await this.uploadFile(filePath, filePath);
    const pdfUri = decodeURIComponent(pdfUriCode);
    this.domainList = {
      pdfSize: res.pdfSize,
      pdfUri: pdfUri.substring(pdfUri.indexOf('root')),
    };

downloadPdfHandler函數(shù)實(shí)現(xiàn)文章來(lái)源地址http://www.zghlxwxcb.cn/news/detail-851973.html

  downloadPdfHandler(page, downloadPath): Promise<any> {
    const uuidName = uuidv4();
    const fsWatchApi = () => {
      // 使用防抖是為了防止下載的文件沒(méi)有寫入完全就重命名，那樣會(huì)產(chǎn)生一個(gè)臟文件
      let timer: any = null;
      return new Promise<{ filename: string }>(resolve => {
        fs.watch(downloadPath, async (_eventType, filename) => {
          if (timer !== null) {
            clearTimeout(timer);
          }
          timer = setTimeout(() => {
            // 防止出現(xiàn)下載的臨時(shí)文件就觸發(fā)
            if (filename.endsWith('.pdf')) {
              resolve({
                filename,
              });
            }
          }, 500);
        });
      });
    };

    function responseWatchApi() {
      return new Promise<void>(resolve => {
        page.on('response', async response => {
          // 檢查響應(yīng)是否為application/octet-stream且可能包含PDF（或你期望的其他文件類型）
          if (response.headers()['content-type'].startsWith('application/octet-stream')) {
            resolve();
          }
        });
      });
    }

    return new Promise(async (resolve, reject) => {
      try {

        const [ , { filename }] = await Promise.all([ responseWatchApi(), fsWatchApi() ]);
        const oldFilePath = path.join(downloadPath, filename);
        const newFilePath = path.join(downloadPath, `${uuidName}.pdf`);
        try {
          fs.renameSync(oldFilePath, newFilePath);
          this.logger.info(`文件名已經(jīng)被修改完成:${uuidName}`);
        } catch (error) {
          this.logger.info(`文件名已經(jīng)被修改完成:${uuidName}`);
        }
        await this.sleep(5 * 1000);
        const files = fs.readdirSync(downloadPath);
        // 創(chuàng)建一個(gè)數(shù)組，將文件名和其mtime（最后修改時(shí)間）一起存儲(chǔ)
        const filesWithMtime = files.map(file => {
          const filePath = path.join(downloadPath, file);
          const stats = fs.statSync(filePath);
          return { fileName: file, mtime: stats.mtime, size: stats.size };
        });
        const newestFile = filesWithMtime.sort((a, b) => b.mtime.getTime() - a.mtime.getTime())[0];
        this.logger.info('newestFile: %o', {
          newestFile,
        });
        resolve({
          pdfSize: newestFile.size,
          fileName: newestFile.fileName,
        });

      } catch (e) {
        reject(e);
      }
    });
  }

到了這里，關(guān)于使用puppeteer完成監(jiān)聽瀏覽器下載文件并保存到自己本地或服務(wù)器上完成上傳功能的文章就介紹完了。如果您還想了解更多內(nèi)容，請(qǐng)?jiān)谟疑辖撬阉鱐OY模板網(wǎng)以前的文章或繼續(xù)瀏覽下面的相關(guān)文章，希望大家以后多多支持TOY模板網(wǎng)！