OAuth 2.0 Client Credentials works in Postman but not from ServiceNow-to-ServiceNow (401 error)

[dd31]

Hi all,

I followed all the steps to set up OAuth 2.0 Client Credentials for a ServiceNow-to-ServiceNow integration:

1. In Instance A (target), created an OAuth Provider (Application Registry) with Client ID, Client Secret, and Redirect URL. Associated a user (with admin role) under OAuth application user.

2. In Instance B (caller), created an Application Registry to consume Instance A’s credentials (client id, secret, token URL, grant type = Client Credentials).

3. In Instance B, created a REST Message pointing to Instance A’s Table API, set Authentication type = OAuth 2.0

4. Clicked on Get OAuth Token — token is generated successfully.

5. But when I test the HTTP method (GET) in the REST Message, I get:

401 User Not Authenticated - Required to provide Auth information

[Ankur Bawiskar]

@dd31 

share the script you are using.

It should work fine

If my response helped please mark it correct and close the thread so that it benefits future readers.

[dd31]

hi @Ankur Bawiskar 

I have created a simple REST message using OAuth 2.0 for authentication and the GET HTTP method, targeting the table API of target ServiceNow instance. When I click 'Get OAuth Token,' it retrieves the token successfully, but when I click 'Test' under Related Links, it returns this message: {"error":{"message":"User Not Authenticated","detail":"Required to provide Auth information"},"status":"failure"} Method failed: (/api/now/table/sys_user) with code: 401 - Invalid username/password combo

[Ankur Bawiskar]

@dd31 

how it behaves when you run background script?

you should first get access token and then use that in actual API call.

If my response helped please mark it correct and close the thread so that it benefits future readers.

[dd31]

var clientId = "****";
var clientSecret = "**"; 
var tokenUrl = "https://*****.service-now.com/oauth_token.do";

var tokenRequest = new sn_ws.RESTMessageV2();
tokenRequest.setHttpMethod("post");
tokenRequest.setEndpoint(tokenUrl);
tokenRequest.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");

var tokenBody = "grant_type=client_credentials"
+ "&client_id=" + encodeURIComponent(clientId)
+ "&client_secret=" + encodeURIComponent(clientSecret);

tokenRequest.setRequestBody(tokenBody);

var tokenResponse = tokenRequest.execute();
var tokenStatus = tokenResponse.getStatusCode();
var tokenBodyResp = tokenResponse.getBody();

gs.info("Token Status: " + tokenStatus);
gs.info("Token Response: " + tokenBodyResp);

// Parse access token
var tokenJson = JSON.parse(tokenBodyResp);
var accessToken = tokenJson.access_token;
gs.info("Access Token: " + accessToken);

var apiUrl = "https://****.service-now.com/api/now/table/sys_user?sysparm_limit=5";
var apiRequest = new sn_ws.RESTMessageV2();
apiRequest.setHttpMethod("get");
apiRequest.setEndpoint(apiUrl);

apiRequest.setRequestHeader("Authorization", "Bearer " + accessToken);
apiRequest.setRequestHeader("Accept", "application/json");

var apiResponse = apiRequest.execute();
var apiStatus = apiResponse.getStatusCode();
var apiBody = apiResponse.getBody();

gs.info("API Status: " + apiStatus);
gs.info("API Response: " + apiBody);
gs.info("API Error Message: " + apiResponse.getErrorMessage());

Although i am able to retrieve the access token, but when i hit the main table api, i am getting exactly same error in background script, i tried on 2 of my personal PDIs, there also i am facing a similar issue.