Question

我正在尝试使用 Archiverjs 为从 Firebase存储流式传输的多个文件创建一个zip文件，而且已归档的文件也将作为即时响应流式传输到客户端，但在完成后归档结果，即在客户端上下载是不合适的，所有文件都在zip中，但是其中一些文件的大小为0。

const archiver = require("archiver");
const fs = require("fs");

const downloadZip = async ({ items }, response) => {
  try {
    const archive = archiver("zip");
    archive.on("error", err => {
      archive.unpipe();
      archive.destroy();
      console.error("Error :: ", err);
      throw err;
    });
    archive.on("end", () => {
      archive.unpipe();
      archive.destroy();
      console.log("Archiver ends & zip sent.");
    });

    response.writeHead(200, {
      "Content-Type": "application/zip",
      "Content-Disposition": `attachment; filename="testItems.zip"`,
      "Access-Control-Allow-Origin": "*",
      "Access-Control-Allow-Methods": "GET, POST, OPTIONS"
    });
    //Piping archive to response so that user can receive the response while archiving
    archive.pipe(response);
    const bucket = storage.bucket("test-bucket");
    const promiseLimit = 5;

    //Streaming files in multiple Promise.all and appending it into archiver
    while (items.length) {
      await Promise.all(
        items.splice(0, promiseLimit).map(item => {
          return new Promise((resolve, reject) => {
            const fileName = item.fileName;
            const path = item.path;
            if (bucket && fileName) {
              //Create read stream of firebase storage file
              const readableStream = bucket.file(path).createReadStream();
              //Save same files on local, for testing i.e make sure that archived files are same to these files
              readableStream.pipe(fs.createWriteStream(fileName));
              //Appending Readable stream to archiver
              archive.append(readableStream, { name: fileName });
              readableStream.on("data", data => {});
              readableStream.on("error", error => {
                console.error("Downloading error : ", error);
              });
              readableStream.on("end", () => {
                console.error("Downloading complete : ", fileName);
                readableStream.destroy();
                resolve({});
              });
              readableStream.on("close", () => {
                console.log("Connection closed : ", fileName);
                resolve({});
              });
            } else {
              resolve({});
            }
          });
        })
      );
    }
    archive.finalize();
  } catch (err) {
    console.error("Error : ", err);
  }
};

对我来说，似乎无法处理显示文件已完全下载的Firebase事件“结束”。我也使用单个“全部承诺”来尝试相同的操作，但也无济于事。

使用流归档文件时Archiverjs的异常行为

0 个答案: