fix(agent): Slim txn naming updates (#917)

1) the scheme for route run to correlate with proper OAPI naming was
incorrectly listed and therefore txn naming precedence was incorrectly
handled
2) this PR kept same naming scheme in route:run putting it before
wrapper_call and saying ok to overwrite (instead of after and not ok to
overwrite)
3) number 2 needed to incorporate fallback naming scheme 
4) added fallback naming scheme (since some errors and middleware
intervention give the wrong txn name) using dispatcher:dispatch.

When there is an exception thrown in a route that is handled by the slim
routing and error middleware, it is superseded by: Uncaught exception
'Slim\\Exception\\HttpNotFoundException' with message 'Not found.' and
transformed into an http 404 error and is shown in the http.statuscode
field as 404. If the middleware isn't loaded, it is recorded as an
uncaught exception and status code is 200.

Wrap function Slim\\Routing\\Dispatcher::dispatch
It will name set the txn_name in case we hit an error and
Slim\\Routing\\Route::run isn't called. It is set to be overwritable do
that if we encounter Slim\\Routing\\Route::run, it can overwrite with
the most accurate info (this is only relevant in the case of redirects).
This allows us to give the txn_name even in error cases when
Slim\\Routing\\Route::run isn't called.

Corresponds with multiverse updates which passed against this branch.

Author: zsistla

agent/fw_slim.c

@@ -81,28 +81,65 @@ NR_PHP_WRAPPER(nr_slim2_route_dispatch) {
 NR_PHP_WRAPPER_END
 
 /*
- * Wrap the \Slim\Route::run method, which is the happy path for Slim routing.
+ * Wrap the Slim 3\Slim\Route::run method
+ * and
+ * Slim 4 Slim\\Routing\\Route::run
+ * which are the happy paths for Slim 3/4 routing.
  * i.e. The router has succesfully matched the URL and dispatched the request
  * to a route.
  *
- * In this case, `nr_txn_set_path` is called after `NR_PHP_WRAPPER_CALL` with
- * `NR_OK_TO_OVERWRITE` and as this corresponds to calling the wrapped function
- * in func_end no change is needed to ensure OAPI compatibility as it will use
- * the default func_end after callback. This entails that the first wrapped
- * function call of this type gets to name the txn.
+ * In this case, `nr_txn_set_path` is called before `NR_PHP_WRAPPER_CALL` with
+ * `NR_OK_TO_OVERWRITE` and as this corresponds to calling the last wrapped
+ * function call of this type gets to name the txn; therefore needs a before
+ * call for OAPI.
  */
 NR_PHP_WRAPPER(nr_slim3_4_route_run) {
   zval* this_var = NULL;
   char* txn_name = NULL;
 
   (void)wraprec;
+
   NR_PHP_WRAPPER_REQUIRE_FRAMEWORK(NR_FW_SLIM);
 
   this_var = nr_php_scope_get(NR_EXECUTE_ORIG_ARGS TSRMLS_CC);
   txn_name = nr_slim_path_from_route(this_var TSRMLS_CC);
   nr_php_scope_release(&this_var);
 
+  if (txn_name) {
+    nr_txn_set_path("Slim", NRPRG(txn), txn_name, NR_PATH_TYPE_ACTION,
+                    NR_OK_TO_OVERWRITE);
+    nr_free(txn_name);
+  }
+
   NR_PHP_WRAPPER_CALL;
+}
+NR_PHP_WRAPPER_END
+
+/*
+ * public function dispatch(string $method, string $uri): RoutingResults
+ * This is fallback naming mechanism for Slim 4 routing when the Slim 4
+ * Slim\\Routing\\Route::run does not run due middlware intervening on
+ * certain errors.
+ * In this case, `nr_txn_set_path` is called before `NR_PHP_WRAPPER_CALL` with
+ * `NR_NOT_OK_TO_OVERWRITE` and as this corresponds to calling the first wrapped
+ * function in func_begin.
+ */
+NR_PHP_WRAPPER(nr_slim4_route_dispatch) {
+  char* txn_name = NULL;
+  zval* route_name = NULL;
+
+  (void)wraprec;
+
+  NR_PHP_WRAPPER_REQUIRE_FRAMEWORK(NR_FW_SLIM);
+
+  /* Get the route name. The first arg is the method, 2nd arg is routename. */
+  route_name = nr_php_arg_get(2, NR_EXECUTE_ORIG_ARGS);
+
+  if (nr_php_is_zval_valid_string(route_name)) {
+    txn_name = nr_strndup(Z_STRVAL_P(route_name), Z_STRLEN_P(route_name));
+  }
+
+  nr_php_arg_release(&route_name);
 
   if (txn_name) {
     nr_txn_set_path("Slim", NRPRG(txn), txn_name, NR_PATH_TYPE_ACTION,
@@ -120,7 +157,7 @@ NR_PHP_WRAPPER(nr_slim_application_construct) {
   (void)wraprec;
 
   version = nr_php_get_object_constant(this_var, "VERSION");
-  
+
   if (NRINI(vulnerability_management_package_detection_enabled)) {
     // Add php package to transaction
     nr_txn_add_php_package(NRPRG(txn), PHP_PACKAGE_NAME, version);
@@ -139,12 +176,34 @@ void nr_slim_enable(TSRMLS_D) {
 
   nr_php_wrap_user_function(NR_PSTR("Slim\\Route::dispatch"),
                             nr_slim2_route_dispatch TSRMLS_CC);
+
+#if ZEND_MODULE_API_NO >= ZEND_8_0_X_API_NO \
+    && !defined OVERWRITE_ZEND_EXECUTE_DATA
+
   /* Slim 3 */
-  nr_php_wrap_user_function(NR_PSTR("Slim\\Route::run"),
-                            nr_slim3_4_route_run TSRMLS_CC);
+  nr_php_wrap_user_function_before_after_clean(
+      NR_PSTR("Slim\\Route::run"), nr_slim3_4_route_run, NULL, NULL);
+
   /* Slim 4 */
+  nr_php_wrap_user_function_before_after_clean(
+      NR_PSTR("Slim\\Routing\\Route::run"), nr_slim3_4_route_run, NULL, NULL);
+
+  /* Slim 4 */
+  nr_php_wrap_user_function_before_after_clean(
+      NR_PSTR("Slim\\Routing\\Dispatcher::dispatch"), nr_slim4_route_dispatch,
+      NULL, NULL);
+#else
+  /* Slim 4*/
   nr_php_wrap_user_function(NR_PSTR("Slim\\Routing\\Route::run"),
                             nr_slim3_4_route_run TSRMLS_CC);
+  /* Slim 4 */
+  nr_php_wrap_user_function(NR_PSTR("Slim\\Routing\\Dispatcher::dispatch"),
+                            nr_slim4_route_dispatch TSRMLS_CC);
+
+  /* Slim 3 */
+  nr_php_wrap_user_function(NR_PSTR("Slim\\Route::run"),
+                            nr_slim3_4_route_run TSRMLS_CC);
+#endif
 
   /* Slim 2 does not have the same path as Slim 3/4 which is why
     we need to separate these*/