Changeset 9564

Timestamp:

03/04/2020 05:10:57 AM (5 years ago)

Author:

dd32

Message:

Trac: Github PRs: Switch to using a Github App Token for authentication with Github.

This significantly increases the number of API requests that can be made per hour, and enables access to several additional API endpoints.

This uses the MIT licensed ​https://github.com/adhocore/php-jwt to generate the JWTs as required by the Github App API.

See #4903, #5052.

Location:

sites/trunk/api.wordpress.org/public_html/dotorg/trac/pr

Files:

• adhocore-php-jwt (added)
• adhocore-php-jwt/JWT.php (added)
• adhocore-php-jwt/JWTException.php (added)
• adhocore-php-jwt/ValidatesJWT.php (added)
• functions.php (modified) (2 diffs)
• webhook.php (modified) (1 diff)

sites/trunk/api.wordpress.org/public_html/dotorg/trac/pr/functions.php

@@ -72 +72 @@
             [
                 'Accept: application/json',
-                'Authorization: ' . get_authorization_token(),
+                'Authorization: ' . get_authorization_token( $url ),
             ],
             $headers
@@ -89 +89 @@
  * Fetch an Authorization token for a Github API request.
  */
-function get_authorization_token() {
-    global $wpdb;
-
-    // TODO: This needs to be switched to a Github App token.
-    // This works temporarily to avoid the low unauthenticated limits.
-    return 'BEARER ' . $wpdb->get_var( "SELECT access_token FROM wporg_github_users WHERE github_user = 'dd32'");
+function get_authorization_token( $url ) {
+    // There are two different tokens used, JWT and App Installation tokens.
+    if ( false !== stripos( $url, 'api.github.com/app' ) ) {
+        // App Endpoint, that's a JWT token
+        return 'BEARER ' . get_jwt_app_token();
+    } else {
+        // Regular Endpoint, use an App Installation token
+        return 'BEARER ' . get_app_install_token();
+    }
+}
+
+/**
+ * Fetch a JWT Authorization token for the Github /app API endpoints.
+ */
+function get_jwt_app_token() {
+    $token = wp_cache_get( GH_TRAC_APP_ID, 'API:JWT-token' );
+    if ( $token ) {
+        return $token;
+    }
+
+    include_once __DIR__ . '/adhocore-php-jwt/ValidatesJWT.php';
+    include_once __DIR__ . '/adhocore-php-jwt/JWTException.php';
+    include_once __DIR__ . '/adhocore-php-jwt/JWT.php';
+
+    $key = openssl_pkey_get_private( base64_decode( GH_TRAC_APP_PRIV_KEY ) );
+    $jwt = new \Ahc\Jwt\JWT( $key, 'RS256' );
+
+    $token = $jwt->encode([
+        'iat' => time(),
+        'exp' => time() + 10*60,
+        'iss' => GH_TRAC_APP_ID,
+    ]);
+
+    // Cache it for 9 mins (It's valid for 10min)
+    wp_cache_set( GH_TRAC_APP_ID, $token, 'API:JWT-token', 9 * 60 );
+
+    return $token;
+}
+
+/**
+ * Fetch an App Authorization token for accessing Github Resources.
+ * 
+ * This assumes that the Github App will only ever be installed on the @WordPress organization.
+ */
+function get_app_install_token() {
+    $token = wp_cache_get( GH_TRAC_APP_ID . '-install-token', 'API:JWT-token' );
+    if ( $token ) {
+        return $token;
+    }
+
+    $installs = api_request(
+        '/app/installations',
+        null,
+        [ 'Accept: application/vnd.github.machine-man-preview+json' ]
+    );
+    if ( ! $installs || empty( $installs[0]->access_tokens_url ) ) {
+        return false;
+    }
+
+    $access_token = api_request(
+        $installs[0]->access_tokens_url,
+        null,
+        [ 'Accept: application/vnd.github.machine-man-preview+json' ],
+        'POST'
+    );
+    if ( ! $access_token || empty( $access_token->token ) ) {
+        return false;
+    }
+
+    $token     = $access_token->token;
+    $token_exp = strtotime( $access_token->expires_at );
+
+    // Cache the token for 1 minute less than what it's valid for.
+    wp_cache_set( GH_TRAC_APP_ID . '-install-token', $token, 'API:JWT-token', $token_exp - time() - 60 );
+
+    return $token;
 }
 

sites/trunk/api.wordpress.org/public_html/dotorg/trac/pr/webhook.php

@@ -4 +4 @@
 require dirname( dirname( dirname( __DIR__ ) ) ) . '/init.php';
 require dirname( dirname( dirname( __DIR__ ) ) ) . '/includes/hyperdb/bb-10-hyper-db.php';
+require dirname( dirname( dirname( __DIR__ ) ) ) . '/includes/object-cache.php';
+\wp_cache_init();
 
 require __DIR__ . '/functions.php';