SAPUI5 using bearer Token in CF failing

[chayanhardrock85]

I am trying to call external API using BTP Business Studio for SAPUi5 App

1) API first needs to get the bearer Token, I have created destination using Basic Authentication.

In SAPUI5 code

var url = "/oauth/token?grant_type=client_credentials";
var ajaxRequest = {};
            ajaxRequest.url = url;
            ajaxRequest.method = "GET";
            ajaxRequest.headers = header;
            ajaxRequest.contentType = true;
            ajaxRequest.processData = false;
            ajaxRequest.success = successcallback.bind(this);
            jQuery.ajax(ajaxRequest);

Bearer Token is getting returned

View1.controller.js:153 {Authorization: 'Bearer eyJhbGciOiJSUzI1NiIsImprdSI6Imh0dHBzOi8vZDF…aIL-ZziUPK1DqXUmApUNEr1n8BiSwDjZfwbAKQKuoTuS8N4TQ'}

2) Using Bearer Token , data needs to be fetched. In Second step failing

jquery-dbg.js:10216 POST https://workspaces-ws-wllq8-app1.eu10.trial.applicationstudio.cloud.sap/document-information-extract... 503

controller

var url = "/document-information-extraction/v1/document/jobs";
var ajaxRequest = {};
            ajaxRequest.url = url;
            ajaxRequest.method = "POST";
            ajaxRequest.headers = header;
            ajaxRequest.data = data;
            ajaxRequest.processData = false;
            ajaxRequest.contentType = false;
            ajaxRequest.mimeType = "multipart/form-data";
            ajaxRequest.success = successcallback.bind(this);
            ajaxRequest.error = failcallback.bind(this);
            jQuery.ajax(ajaxRequest);

ui5.yaml

      backend:
       - path: /oauth
         destination: DocExtract
       - path: /document-information-extraction
         destination: DocExtract_CLONING

xs-app.json

  "routes": [
    {
      "source": "^/oauth/(.*)$",
      "target": "/oauth/$1",
      "destination": "DocExtract",
      "authenticationType": "xsuaa",
      "csrfProtection": false
    },
    {
      "source": "^/document-information-extraction/(.*)$",
      "target": "/document-information-extraction/$1",
      "destination": "DocExtract_CLONING",
      "authenticationType": "none",
      "csrfProtection": false
    },

[mariusobert]

I think you're using the destinations incorrectly here. Afaik it's not possible to communicate with the authentication.eu10.hana.ondemand.com endpoint via basic authentication.

And there's also no need to fetch OAuth tokens from the UI5 app as you can use the approuter for this. I recommend that you read my post Using the Destination service in SAP BTP, Cloud Foundry Environment. I hope this explains all the needed details for you use-case.