Hi Nitin,

You will need to pass the file as a separate input parameter of type Binary Data with Send In = Request Part. 

You can’t include the binary directly in the JSON because multipart/form-data sends each field (including files) as separate parts. JSON can't handle raw binary properly in that format.

So, define all fields (user_name, .....) as Request Parts, and add one more for file_content as Binary Data. That should work.

Hope this helps.

@Nitin Chavan : Please have a look at the documentation provided at https://success.outsystems.com/documentation/11/integration_with_external_systems/rest/consume_rest_apis/payload_request_examples_when_consuming_a_single_rest_method/ . Refer to section "Multipart/form-data". Do copy the sample shown there and put in your code and make necessary changes - move your fields in respective boundary and test the code and it should work.

Yes, since you're using multipart/form-data as the request format in OutSystems and your request includes a binary file, you cannot include the file binary inside a custom structure as a regular field like "file_content": <>. Instead, you must define it as a separate input parameter using the RequestPart data type.

Recommended Approach in OutSystems

To send binary content via multipart/form-data, do the following in your consumed REST API method definition:

Define Input Parameters:

• For all non-binary values (e.g., user_name, client_id, etc.), add input parameters of type Text/Integer.

• For file_content, add:

  • Name: file_content

  • Data Type: Binary Data

  • Send In: Body

  • Type: Request Part

No,
Can you check the both OML I have exposed api from one and consume from another with binary data.

https://amitj.outsystemscloud.com/App02/Screen1?_ts=638889819646430408

Another module 

Please install both and test by correcting the consumer api url, it will work

Can you try to keep json instead of Multipart/form-data.
Can you check now again new changes in modules i am able to send the FIle  data as  base64

Also send file data as Base64 in the request body when consuming an API — and this is a common and valid approach, especially when working with REST APIs that expect JSON.

JSON limitation: JSON does not support binary directly — only text (including Base64).

Platform compatibility: Base64 works seamlessly across platforms (like browsers, mobile apps, OutSystems, etc.).

API support: Many APIs (especially in OutSystems) are designed to accept Base64 strings for files.

In OutSystems, when consuming a REST API: You can only send a Base64 string (not raw binary) in a text input parameter. If you're using Binary Data as input, it must still be Base64-encoded on the client or calling side. 

Can you try to keep json instead of Multipart/form-data.
Can you check now again new changes in modules i am able to send the FIle  data as  base64

Also send file data as Base64 in the request body when consuming an API — and this is a common and valid approach, especially when working with REST APIs that expect JSON.

JSON limitation: JSON does not support binary directly — only text (including Base64).

Platform compatibility: Base64 works seamlessly across platforms (like browsers, mobile apps, OutSystems, etc.).

API support: Many APIs (especially in OutSystems) are designed to accept Base64 strings for files.

In OutSystems, when consuming a REST API: You can only send a Base64 string (not raw binary) in a text input parameter. If you're using Binary Data as input, it must still be Base64-encoded on the client or calling side. 

Another OML