如何使用node.js为上传到谷歌云存储的文件设置内容类型

Question

我正在编写代码，将使用node-fetch获取的文件上传到Google Cloud Storage中使用gcloud-node的存储桶中。

到目前为止，一切都很正常，但我在找出如何在GCloud上设置文件的Content-Type时遇到了麻烦，否则该文件将以application/octet-stream格式下载。

这是我到目前为止所拥有的代码：

function saveImage(response, destFile) {
  return new Promise((resolve, reject) => {
    if (response.status !== 200) {
      reject(new Error('Bad Response'));
    }

    // How do I set this on the file uploaded to the bucket?
    const contentType = response.headers.get('Content-Type');

    try {
      const file = bucket.file(destFile);
      const writeStream = file.createWriteStream();

      writeStream.on('error', err => {
        reject(err);
      });

      writeStream.on('finish', () => {
        resolve(getPublicUrl(destFile));
      });

      response.body.pipe(writeStream);
    } catch (e) {
      reject(e);
    }
  });
}

Answer 1

原来在文件上有一个setMetadata方法，您可以调用它将Content-Type作为参数传递。下面是工作代码的样子：

function saveImage(response, destFile) {
  return new Promise((resolve, reject) => {
    if (response.status !== 200) {
      reject(new Error('Bad Response'));
    }

    const contentType = response.headers.get('Content-Type');
    try {
      const file = bucket.file(destFile);

      const writeStream = file.createWriteStream({
        metadata:{
          contentType: contentType
        }
      });

      writeStream.on('error', err => {
        reject(err);
      });

      writeStream.on('finish', () => {
        resolve(getPublicUrl(destFile));
      });

      response.body.pipe(writeStream);
    } catch (e) {
      reject(e);
    }
  });
}