// First, create an instance of the OAuth2 server $server = new OAuth2\Server([ 'access_token_lifetime' => 3600, 'store' => new OAuth2\Storage\Pdo(['dsn' => 'mysql:dbname=oauth2;host=localhost', 'username' => 'root', 'password' => 'password']), 'issuer' => 'https://example.com' ]); // Then, add a client to the server $server->addClient('client_id', 'client_secret'); // Next, define a scope that users can grant access to $server->addScope('protected_scope'); // Then, protect a resource with the required scope $server->addProtectedResource('/api/protected', ['protected_scope']); // Finally, authenticate the user and generate an access token $token = $server->grantAccessToken(OAuth2\Request::createFromGlobals());In this example, the OAuth2 server is created with a specific access token lifetime, and a PDO database connection is used to store client credentials. A single client is added to the server, along with a scope that can be granted access to. A protected resource is defined that requires the "protected_scope" scope to access. Finally, the user is authenticated using request data, and an access token is granted if the authentication is successful.