Unwanted "content-type: text/plain;charset=UTF-8" header in Google Drive API Response

Question

I am using the browser GAPI library to request a piece of binary data from Google Drive. The response from the google server always has a content-type: text/plain;charset=UTF-8 header, because of which, the browser always decoded the binary data into a UTF-8 character string.

What's more, the decoding process seems to add padding to the original binary data. For example, a 282-byte binary after UTF-8 decoding becomes 422-bytes long.

Is there any way to tell the Google API server to change the content-type header?

Or is there a way to bypass the preprocessing of the response body and get the raw response instead?

My code for requesting is listed here:

currentApiRequest = {
    path: `https://www.googleapis.com/drive/v3/files/${fileID}`,
    params: {
        alt: "media"
    }
}
gapi.client.request(currentApiRequest).then(
    (response) => {
                let data = response.body;
                console.log(byteSize(data));
                console.log(data);
    }
)

If its binary data why not just use the webContentLink ? – Linda Lawton - DaImTo Mar 25 '21 at 12:04 — Linda Lawton - DaImTo, Mar 25 '21 at 12:04
Because of cors, I simply cannot fetch a webContentLink... – Hongyi LI Mar 26 '21 at 14:03 — Hongyi LI, Mar 26 '21 at 14:03

score 1 · Accepted Answer · answered Mar 26 '21 at 01:23

How about the following modification? In this modification, at first, the retrieved data is converted to Unit8Array and converted it to the blob.

Modified script:

const fileID = "###"; // Please set your file ID.
currentApiRequest = {
  path: `https://www.googleapis.com/drive/v3/files/${fileID}`,
  params: {alt: "media"}
};
gapi.client.request(currentApiRequest)
.then((response) => {
  let data = response.body;
  const blob = new Blob([new Uint8Array(data.length).map((_, i) => data.charCodeAt(i))]);

  // When you use the following script, you can confirm whether this blob can be used as the correct data.
  const filename = "sample.png"; // Please set the sample filename.
  const a = document.createElement('a');
  document.body.appendChild(a);
  a.href = URL.createObjectURL(blob);
  a.download = filename;
  a.click();
});

References:

gapi.client.request(args)
Related thread.
- How do you download an image with Google Drive api V3 to a browser client?
- In this thread, the data retrieved from gapi.client.drive.files.get() is used. On the other hand, in this question, the data retrieved from gapi.client.request() is used. I thought that this might be also useful for other users. So I posted this answer without flagging as the duplication.

Unwanted "content-type: text/plain;charset=UTF-8" header in Google Drive API Response

1 Answers1

Modified script:

References: