Passing a Buffer to .attach

[mikemorton]

The following works fine for me:

  unirest.put(`${URL_BASE}/api/v1/Databases/${DBID}/Records/${RECORDID}/Content/${FIELDID}`)
  .headers({'Content-Type': 'multipart/form-data'})
  .attach('asdf', fs.createReadStream('V:/Multimedia/pumpkins.jpg'))
  .auth({user:USERNAME, pass:PASSWORD})
  .end(function (res) {
    console.log('statusCode:', res && res.statusCode);

    console.log('body:', res.body);
  });

However the next thing I'd like to do do is send large uploads in chunks. I can divide the file into chunks as Buffer objects but sending the buffer to attach does not seem to work for me:

  var bufferStream = new stream.PassThrough();
  bufferStream.end(Buffer.from(buffer));

  unirest.put(`${URL_BASE}/api/v1/Databases/${DBID}/Records/${RECORDID}/Content/${FIELDID}`)
  .headers({'Content-Type': 'multipart/form-data'})
  .attach('asdf', bufferStream)
  .auth({user:USERNAME, pass:PASSWORD})
  .end(function (res) {
    console.log('statusCode:', res && res.statusCode);

    console.log('body:', res.body);
  });

Yields the folowing error:

TypeError [ERR_HTTP_INVALID_HEADER_VALUE]: Invalid value "undefined" for header "Content-Length"
at ClientRequest.setHeader (_http_outgoing.js:473:3)
at FormData. (V:\Work\upload test\node_modules\unirest\node_modules\form-data\lib\form_data.js:321:13)
at V:\Work\upload test\node_modules\unirest\node_modules\form-data\lib\form_data.js:265:7
at V:\Work\upload test\node_modules\async\lib\async.js:251:17
at done (V:\Work\upload test\node_modules\async\lib\async.js:126:15)
at V:\Work\upload test\node_modules\async\lib\async.js:32:16
at V:\Work\upload test\node_modules\async\lib\async.js:248:21
at V:\Work\upload test\node_modules\async\lib\async.js:572:34
at V:\Work\upload test\node_modules\unirest\node_modules\form-data\lib\form_data.js:105:13
at FSReqWrap.oncomplete (fs.js:153:21)

What is the correct way to send a raw stream to .attach() ?

[Daniyal83]

Hello. I think I have the same issue when trying to send with content-type: multipart/form-data. Have you solved the problem?

[mikemorton]

I never really got it working. Since I was just writing some demo-level scratch code I wrote the buffer to a temporary file and sent the temp file using .attach('asdf', fs.createReadStream('V:/Multimedia/pumpkins.jpg')).

[Daniyal83]

I hope someone will answer and solve the issue.

[huan]

I run into this issue today with a Readable stream.

It seems that we have to use an FS Readable stream for this API method.

It would be great if we could use a Readable stream for this API!

[huan]

It turns out that the unirest are using the NPM module form-data, and the form-data module requires that if it received a stream that not fs.ReadStream, we need to provide the file information by additional.

Example:

form.append( 
  'my_file', 
  stream,
  {
    filename: 'bar.jpg', 
    contentType: 'image/jpeg', 
    knownLength: 19806,
  },
)

See: https://github.com/form-data/form-data#void-append-string-field-mixed-value--mixed-options-