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Content-Type boundary issue when uploading a file

(Paul Barnes) #1


I have a chrome extension that is using backendless to upload a file. The code is :

		var request = new XMLHttpRequest();'POST', '<API-KEY-OBSCURED>/<REST_API_KEY_OBSCURED>/files/binary/testName.webm?overwrite=true');
		request.setRequestHeader('Content-Type','multipart/form-data; boundary=RECORD_BOUNDARY');
		request.onload = function() {
			// Do Something 		

		var recorderBlob = { body: recorder.getBlob(), name: "testName.webm" };
                   // recorder.getBlob is a video/webm object containing a recorded screen

But the response returns a 400 with the following :

response = “{“code”:8002,“message”:“Could not parse request with message: Unexpected end of input, status code 400, headers POST /D5F0DFFA-0C36-CC73-FF39-171676325B00/A2C876F2-6E9C-EE22-FF0E-7C00506E6700/files/binary/testName.webm?overwrite=true”,“errorData”:{}}”

The documentation for the binary file upload does not describe what to do with the ‘boundary’ directive, but the API seems to need it.

Please can you advise ?


(Mark Piller) #2

Hi Paul,

I think it is an error in the documentation. I see the Example section here uses the following: Content-Type: text/plain. Could you please try making that change and see if it works for you?


(Paul Barnes) #3

Hi Mark

Thanks for the quick reply.

I changed the content-type to text/plain.

Unfortunately, I still get this response expecting the ‘multipart/form-data’ :slight_smile:

response = “{“code”:6010,“message”:“Corrupted multipart request. Header Content-Type must be set to value multipart/form-data”,“errorData”:{}}”

Any ideas ?


(Paul Barnes) #4

Hi Mark

the example you showed actually shows that it needs a PUT rather than a POST. When using a PUT rather than a POST with that content type, the response returns the 200 with the url to the file.

Though, I now need to understand why the file here, doesn’t look like a valid file -

Any thoughts there ?


(Anton Govorushkin) #5

Hi Paul

POST method is needed for basic file uploading, and PUT is for saving files from byte arrays. A working cURL sample attached.

curlSample.txt (14.7 KB)

I’ve just uploaded a .webm file successfully, please verify whether your base64 body is valid.


(Paul Barnes) #6

Hi Anton

Thanks for that.

My version had some tags for the mime type at the beginning. I’ve stripped those and it now uploads successfully!!