Auto Generate Access token for Oauth 2 Outbound Rest Message

[Divya2411]

I want to connect servicenow with third party integration through Api, but my access token expires everytime. So i want to auto generate the access token everytime its expired. For that need Script code, how to generate it automatically.

I Tried some code but getting the error, "Bearer token is missing in the HTTP request authorization header".

Kindly Help.

[Ahmmed Ali]

You can configure "Application registry" and use authentication as that record in your REST API record. ServiceNow will automatically manage access and refresh tokens.

below videos shows one example:

https://www.youtube.com/watch?v=4uAXcgwjNVQ

https://www.youtube.com/watch?v=QRjjZ911bZE

[Divya2411]

yes, i configure application registry and rest outbound message but if the token expire i need to generate it again manually. I want the script for auto generation of the access token , i tried some code from community but it's not working:-

doIt();

function doIt() {
    var sm = new sn_ws.RESTMessageV2();
    sm.setEndpoint("oauth token endpoint");
    sm.setHttpMethod("post");
    sm.setRequestHeader("Accept", "Application/json");
    sm.setQueryParameter("grant_type", "client_credentials");
    sm.setQueryParameter("client_id", "enter the client_id here");
    sm.setQueryParameter("client_secret", "enter the client_secret here");

    var response = sm.execute();
    var responseBody = response.getBody();
    gs.print(responseBody);


    //Fetch Access Token from Response Body
    var resp = new JSONParser().parse(responseBody);
    gs.print('Access Token: ' + resp.access_token);
}


It showing the errors.

[Ahmmed Ali]

What is the lifespan of refresh token? If access token is expired, new token can be generated using access token. You need to keep the refresh token lifespan more value.