One reason for this is that it requires
multipart/form-data, the de-facto standard for form-based file upload in HTML.
One way of overcoming this is to use Oracle Integration Cloud (OIC) between the JS client and Process REST API. OIC has a REST Technology Adapter that supports sending/receiving attachments in both
multipart/form-data media types. The goal is to shape in OIC a REST interface that accepts
multipart/form-data, to do a translation into
multipart/mixed (alongside with other transformations/actions if required) and to call the Process REST API. Below are the main steps for achieving this.
1. Create a REST Connection in OIC for Process REST API.
Go to OIC Homepage > Designer > Connections to create a new connection by selecting the REST Adapter. Read the complete article here.
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