Convert Appian Document to Base64

Sending Base64 in JSON is supported in Appian 18.3 +

https://docs.appian.com/suite/help/18.3/Integration_Object.html#sending-base64-inline-with-json

How do you integrate this directly into the Web API object?  I have a client trying to access single documents from SAP via an API endpoint I've set up, and regardless of how I try to format the http response, it just passes back either binary data or just the plain document id.

Do these docs help? https://docs.appian.com/suite/help/20.2/passing-a-web-api-document-into-a-process-model.html

I don't see any mention of Base64 there(?).  The remote team is asking to retrieve base64 instead of binary, if possible.

To clarify: I have an API set up where the remote team is passing in a document type and a primary key id.  Logic on our end attempts to retrieve a matching document from the Appian filesystem, and when a match is found, we send it back in the response.  Currently this is going over as binary data, but they're asking if we can convert it to a Base64 string first - and I'm not finding any way to do so (and if it already is, for example, I'm not seeing any way to verify or troubleshoot).

I don't see any mention of Base64 there(?).  The remote team is asking to retrieve base64 instead of binary, if possible.

To clarify: I have an API set up where the remote team is passing in a document type and a primary key id.  Logic on our end attempts to retrieve a matching document from the Appian filesystem, and when a match is found, we send it back in the response.  Currently this is going over as binary data, but they're asking if we can convert it to a Base64 string first - and I'm not finding any way to do so (and if it already is, for example, I'm not seeing any way to verify or troubleshoot).

Hi Mike, Do you have any solution for the above scenario? I am trying to implement something similar.

Hi Shikha, I'm not sure I ever got an answer to my last inquiry from months ago - maybe Danny Verb can provide some additional input?

The best solution would be to upgrade Appian Versions since in 18.3 you can easily send and receive base64 documents.

I was working in 20.1 or 20.2 by the time I wrote my most recent historic question in this thread - (July 2020) - as far as I remember I was never able to figure out the answer.  I can't understand why Appian doesn't just provide a straightforward way of converting a document to base64 (since there used to be a plug-in that would do it directly, as far as I understand).