amplify-js: Amplify v6: It is not possible to set boundaries in REST requests with multipart

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• I have done my best to include a minimal, self-contained set of instructions for consistently reproducing the issue.

JavaScript Framework

React

Amplify APIs

REST API

Amplify Categories

api

Environment information

# Put output below this line

  "dependencies": {
    ...,
    "@aws-amplify/api-rest": "^4.0.5",
    "@aws-amplify/auth": "^6.0.5",
    "@aws-amplify/ui-react": "^6.0.3",
  },

Describe the bug

When i try to submit a Rest request that contains Multipart the framework sets Content-Type to multipart/form-data and it prevents the creatorin of boundary

Content-Type: multipart/form-data; boundary=---------------------------3513053024223207799458523308

https://github.com/aws-amplify/amplify-js/blob/a353e0d777a1ca5e57aa4b2cda48d147ee1d4803/packages/api-rest/src/apis/common/handler.ts#L54

This is a change compared to the v.5.X version.

Am i missing something? Is there any documentation about this change?

Expected behavior

Implement the same behavior that we had with the previous version

Reproduction steps

const form = new FormData(); form.append(parameterName, new Blob([file], { type: file.type }), file.name); post({ apiName, path, options: { body: form } }).response.body.json();

Code Snippet

// Put your code below this line.

Log output

// Put your logs below this line

aws-exports.js

No response

Manual configuration

No response

Additional configuration

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Mobile Device

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Mobile Operating System

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Mobile Browser

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Mobile Browser Version

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Additional information and screenshots

No response