Custom Connector: How to POST binary body?

[Syndicate_Admin]

I have some tests working in Postman that POST binary data (.jpg) to an endpoint. This works just fine, but there is no visible schema for the `body` of this request. Its just "binary data" I guess. 

What do I select in PowerApps Custom Connector to allow binary data in the `body`? Do I need a schema of some sort? 

[murshed]

Hi,

Can you please tell us little more what you are trying to do? Where is this binary data coming from? You can probably work with content-type for this. Also look at this article to work with base64 encoding and binary data: https://linnzawwin.blogspot.com/2021/02/handle-base64-and-binary-file-content.html

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[Syndicate_Admin]

I had the same problem and finally figured it out. You can use the Swagger editor and add a body parameter like this:

      parameters:
      - name: body
        in: body
        schema: {type: string, format: binary}

It appears as a string parameter in the swagger editor and on the custom connector testing tab, but then when you're in the actual flow editor you can put the "File content" from a previous step in there and it gets sent as plain binary. I absolutely did not expect that to work, but it does.

Hope that helps anyone else stumbling across this post because they're stuck on the same thing!

Edit: I later noticed that the paconn validate tool gives a warning that "the MIME type 'application/octet-stream' is not supported" when I try to set the content-type. So maybe what I discovered was a dirty hack, and not the intended behaviour after all.

[Syndicate_Admin]

I was able to figure this out. Believe it or not, the Body was not required!

[Syndicate_Admin]

Glad you figured yours out! I just edited my solution to note that I'm still getting an ominous warning. So far it's been working fine, but what I'm doing doesn't seem to be officially supported.

[Syndicate_Admin]

here is an example from Github:
https://github.com/microsoft/PowerPlatformConnectors/blob/master/custom-connectors/ServiceNow/apiDef...

there is an example POST on line 471 - 644,

631-640 contains the file element

i'm not sure what to make of this information.... but hopefully it helps someone 🙂

(there is a content type element on row 611 - 630 too)

note: the above is in JSON, so you will need to convert to YAML to use in your custom connector

https://www.json2yaml.com/