invalid_grant error code when trying to get the access token

Question

I am able to get the "code" in my redirect Url but unable to get access token.

I tried sending POST request using POSTMAN and also from java code but "invalid_grant" error i got.

Response {"error_description":"invalid authorization code","error":"invalid_grant"}

HttpClient client = new HttpClient();
        PostMethod post = new PostMethod("https://login.salesforce.com/services/oauth2/token");
        post.setParameter("grant_type", "authorization_code");
        post.setParameter("client_id", "MASKED");
        post.setParameter("client_secret", "MASKED");
        post.setParameter("redirect_uri", "https://www.facebook.com/");
        post.setParameter("code", "xxxxxxxxxxxxxxxxxxxxxxxxxxx");

What I am missing in the above code ?

Answer 1

Instead of "https://login.salesforce.com/services/oauth2/token" your should send your request to "https://login.salesforce.com/services/oauth2/authorize" so your code should look like

HttpClient client = new HttpClient();
        PostMethod post = new PostMethod("https://login.salesforce.com/services/oauth2/authorize");
        post.setParameter("grant_type", "authorization_code");
        post.setParameter("client_id", "MASKED");
        post.setParameter("client_secret", "MASKED");
        post.setParameter("redirect_uri", "https://www.facebook.com/");
        post.setParameter("code", "xxxxxxxxxxxxxxxxxxxxxxxxxxx");