How to enable the CORS mode on frontend side in GraphQL/AWS Amplify?

Question

How to do same for GraphQL of AWS Amplify?

fetch('https://trusted-api.co.jp', {
  mode: 'cors'
});

I did not found neither the documentation how to do it nor source code which mention to cors.

Reference

Regular graphQL operation could be called as below:

import AWSAmplifyAPI, { graphqlOperation as graphQL_Operation, GraphQLResult } from "@aws-amplify/api";
import Observable from "zen-observable";

export default class DataBaseService {

  public static async sendRequestAndExtractDataFromResponse(
      graphQL_RawRequest: string,
      requestVariables?: object
  ): Promise<unknown> {

    const serverRawResponse: GraphQLResult | Observable<unknown> =
        await AWSAmplifyAPI.graphql(graphQL_Operation(graphQL_RawRequest, requestVariables));
   // ...
  }
}

Answer 1

You need to configure this on the server side, so the server side needs to approve this "CORS" issue.

Technically your amplify lambda function would add the code similar to:

exports.handler = async (event) => {
  const response = {
    statusCode: 200,
    //  Uncomment below to enable CORS requests
    headers: {
      "Access-Control-Allow-Origin": "*",
    },

    //   headers: {
    //     "Access-Control-Allow-Headers" : "Content-Type",
    //     "Access-Control-Allow-Origin": "https://www.example.com",
    //     "Access-Control-Allow-Methods": "OPTIONS,POST,GET"
    // },
    body: JSON.stringify("Hello from Lambda!"),
  };
  return response;
};