Facing CORS issue when Embeding Power BI in Salesforce Org

Hi,Swetasannbommaj 

Regarding the issue you raised, my solution is as follows:

1.First, you can try to install and enable CORS on the gateway API side with the following command:

npm install cors

Multiple routing files:

const express = require("express");
const router = express.Router();
const cors = require("cors");
router.use(cors());

Single route file:

const express = require("express")
const app = express()
const cors = require("cors")
app.use(cors())

Below are links to related questions:
javascript - React component has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource - Stack Overflow

Here is a link to enable CORS on the gateway API side:
CORS for REST APIs in API Gateway - Amazon API Gateway
 

2.Second, you can also redefine the headers and return:
 

const headers = {'Content-Type':'application/json',
                    'Access-Control-Allow-Origin':'*',
                    'Access-Control-Allow-Methods':'POST,PATCH,OPTIONS'}
const response = {
    statusCode: 200,
    headers:headers,
    body: JSON.stringify(X),
};
return response;

Here are the links to related questions:
aws lambda - Access to fetch at '' from origin '' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource - Stack Overflow
 

3.Finally, you can also try adding mode: 'no-cors' to the fetch method:

fetch(clientConfiguration['communitiesApi.local'], {
    mode: 'no-cors'
  })
  .then((response) => {
      return response.json();                
  })
  .then(data => {
      console.log(data);
      let communitiesFromApi = data.map(community => { return { value: community, display: community } });
      this.setState({ communities: [{ value: '', display: 'Select a Community...' }].concat(communitiesFromApi) });    

  }).catch(error => {
      console.log(error);
  });

Here are the links to related questions:

 javascript - React component has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource - Stack Overflow

Of course, if you have any new ideas, you are welcome to contact us.
 

Best Regards,

Leroy Lu

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