- Generate Code Verifier and Challenge: Use PKCE (Proof Key for Code Exchange) to enhance security.
- Generate State and Nonce: These are used to prevent CSRF attacks and replay attacks, respectively.
- Build Authorization URL: Include required parameters such as
response_type,client_id,redirect_uri,scope,code_challenge,code_challenge_method,state, andnonce.
| Parameter | Description |
|---|---|
response_type | Specifies the type of response. For authorization code flow, use code. |
client_id | The client ID you obtained during client registration. |
redirect_uri | The URI to which the response will be sent. It must match the redirect URI registered with the client. |
scope | A space-separated list of scopes. Use openid. |
code_challenge | The PKCE code challenge. |
code_challenge_method | The method used to generate the code challenge. Use S256. |
state | A random string to maintain state between the request and callback. Helps prevent CSRF attacks. |
nonce | A random string to associate with the ID token. Helps prevent replay attacks. |
response_mode | Specifies how the result should be returned. For this example, use query. |
prompt | Specifies whether the user should be prompted for reauthentication. |
login_hint | email:, social:google, social:facebook |