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Also note that binary content from Table input mode is not converted to Literal mode. All binary configuration should be performed in Table input mode.

Using File Input Values for REST Client and Multipart Form Data

When you’re working with multipart/form-data or url-encoded messages in the REST Client’s table editor, you can populate a table value from a file (in addition to using the standard Fixed/Parameterized/Scripted options). This allows you to embed file contents in the payload.
 

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