如何通过Client_ID、Client_Secret等参数获取Access Token？代码报错求助

Let's break down what's going wrong with your code and fix it step by step:

Key Issues in Your Current Code #

• Incorrect Grant Type & Parameter Names
  • You used authorization_Code (capital C) for grant_type—the correct spelling is authorization_code (lowercase c). But more importantly, since you're passing username and password, you should be using the Password Grant Type, which requires grant_type=password instead of authorization_code (that's for the Authorization Code flow, which needs a pre-obtained code).
  • Your parameter names are wrong: OAuth2 expects client_id and client_secret (snake_case, no spaces), not "Client ID" and "Client Secret".
• Wrong API Endpoint
  • You're sending the POST request to Auth_URL (the authorization page URL), but the correct endpoint for fetching an access token is Access_Token_URL. The Auth_URL is for redirecting users to grant permission and get an authorization code, not directly retrieving tokens.
• Redundant Authentication
  • You're both passing client credentials as form parameters and using preemptive Basic Auth—you only need one of these methods for authentication.

Corrected Code (Password Grant Type) #

Here's the fixed version that should work for the Password flow:

public class Authentication_Token {
    private String clientId = "9d99755c****d";
    private String clientSecret = "dbdb21c0de1b***ab1d4cf6a4b92535ed2";
    private String accessTokenUrl = "https://api.imgur.com/oauth2/token";

    @Test
    public void oauth2PasswordGrant() {
        Response resp = given()
                .contentType("application/x-www-form-urlencoded")
                // Correct parameters for Password Grant Type
                .formParam("grant_type", "password")
                .formParam("client_id", clientId)
                .formParam("client_secret", clientSecret)
                .formParam("username", "testbot@gmail.com")
                .formParam("password", "testbota#1")
                .post(accessTokenUrl);

        // Print response to debug easily
        System.out.println(resp.getBody().asString());
    }
}

Note on Authorization Code Flow (Recommended for Production) #

If you intended to use the more secure Authorization Code Grant Type (better for production apps that don't own the user's credentials), you'll need two steps:

1. Redirect the user to https://api.imgur.com/oauth2/authorize with parameters like client_id, response_type=code, redirect_uri to get an authorization code.
2. Exchange that code for an access token by sending a POST to accessTokenUrl with grant_type=authorization_code, code=YOUR_AUTH_CODE, client_id, client_secret, and redirect_uri.

内容的提问来源于stack exchange，提问作者umeshinator