Image upload with POST

[Jrole]

Hi all,

I want to upload an image (jpeg or png) which is stored locally to an REST API with the “POST Request” Node. In Postman, I’ve “developed” a PoC which also works, so the API itself seems to be OK. Authentication is done by a Bearer, works well. The content of the POST request is a piece of JSON data and the image, “Content-Type” in the header is (and must be) set to “multipart/form-data”.

Whats not working: I do not get the file up to the server, Statuscode 422. The node itself does not gives back a detailed error message (sadly).
Does anyone here has a working example of this node together with multipart form-data?
Or any hints on how to put the image into this node in a way it is accepted? I’ve already tryed it with “Files to binary object” node with or w/o Base64 encoder afterwards. In Postman, everthing works as long as I set in body the key “file” to type “file” (not text).

Thanks you in advance!

[qqilihq]

Hi Jrole,

422 means that the request is not encoded properly, seems like you’re not sending the request as multipart-encoded data.

There’s a node for building multipart requests in Palladian:

Multipart Encoded HTTP Entity Creator

A sample workflow you’ll find here:

HttpRetriever_Multipart_Example

–Philipp

[Jrole]

Thanks a lot, Philipp. Indead, I already worked on exactly this example but didn’t get the authentication working.

[qqilihq]

D’oh This shouldn’t be difficult to fix though. You mention that you have a Bearer token. You’d need to additionally supply this as input column to the HTTP Retriever with a column named Authorization which contains a string value Bearer xxxxxxxxxxxxxxx. Then select it in the Headers tab as follows and it will be sent as HTTP header:

Fingers crossed!

[Jrole]

Jep, works now I have another error message, but this time its coming from the API itself (422) which means: OK, you’re in.