Exposing artificial hook function if scoping is enabled (#49)

* Exposing artificial hook function if scoping is enabled
* Added option to disable emulated opentelemetry extension

Author: intuibase

docs/reference/configuration.md

@@ -57,6 +57,7 @@ opentelemetry_distro.enabled=true
 | Option | Default | Accepted values | Description |
 | --- | --- | --- | --- |
 | `OTEL_PHP_ENABLED` | `true` | `true` or `false` | Enables automatic bootstrap |
+| `OTEL_PHP_OPENTELEMETRY_EXTENSION_EMULATION_ENABLED` | `true` | `true` or `false` | Enables registration of an emulated `opentelemetry` extension, allowing auto-instrumentations to work without `opentelemetry.so` |
 | `OTEL_PHP_NATIVE_OTLP_SERIALIZER_ENABLED` | `true` | `true` or `false` | Enables native OTLP protobuf serializer |
 
 ### Asynchronous data sending

prod/native/extension/code/ModuleEntry.cpp

@@ -181,8 +181,14 @@ PHP_MINIT_FUNCTION(opentelemetry_distro) {
 
     opentelemetry::php::moduleInit(type, module_number);
 
-    if (!zend_register_internal_module(&opentelemetry_distro_fake)) {
-        ELOGF_WARNING(OTEL_G(globals)->logger_, MODULE, "Unable to create artificial OpenTelemetry extension. There might be stability issues.");
+    if (OTEL_G(globals)->config_->get().opentelemetry_extension_emulation_enabled) {
+        if (OTEL_G(globals)->config_->get().debug_scoper_enabled) {
+            opentelemetry_distro_fake.functions = opentelemetry::php::module_functions::opentelemetry_distro_fake_functions;
+        }
+
+        if (!zend_register_internal_module(&opentelemetry_distro_fake)) {
+            ELOGF_WARNING(OTEL_G(globals)->logger_, MODULE, "Unable to create artificial OpenTelemetry extension - opentelemetry.so extension should be disabled. There might be stability issues.");
+        }
     }
 
     return SUCCESS;

prod/native/extension/code/ModuleFunctions.cpp

@@ -385,6 +385,13 @@ const zend_function_entry opentelemetry_distro_functions[] = {
 
     PHP_FE_END
 };
+
+const zend_function_entry opentelemetry_distro_fake_functions[] = {
+    ZEND_NS_FE( "OpenTelemetry\\Instrumentation", hook, hook_arginfo)
+
+    PHP_FE_END
+};
+
 // clang-format on
 
 } // namespace opentelemetry::php::module_functions

prod/native/extension/code/ModuleFunctions.h

@@ -5,5 +5,5 @@
 namespace opentelemetry::php::module_functions {
 
 extern const zend_function_entry opentelemetry_distro_functions[];
-
+extern const zend_function_entry opentelemetry_distro_fake_functions[];
 }

prod/native/libcommon/code/ConfigurationManager.h

@@ -109,6 +109,7 @@ class ConfigurationManager {
         BUILD_OTEL_PHP_OPTION_METADATA(OTEL_PHP_INFERRED_SPANS_SAMPLING_INTERVAL, OptionMetadata::type::duration, false),
         BUILD_OTEL_PHP_OPTION_METADATA(OTEL_PHP_INFERRED_SPANS_MIN_DURATION, OptionMetadata::type::duration, false),
         BUILD_OTEL_PHP_OPTION_METADATA(OTEL_PHP_DEPENDENCY_AUTOLOADER_GUARD_ENABLED, OptionMetadata::type::boolean, false),
+        BUILD_OTEL_PHP_OPTION_METADATA(OTEL_PHP_OPENTELEMETRY_EXTENSION_EMULATION_ENABLED, OptionMetadata::type::boolean, false),
         BUILD_OTEL_PHP_OPTION_METADATA(OTEL_PHP_NATIVE_OTLP_SERIALIZER_ENABLED, OptionMetadata::type::boolean, false),
         BUILD_OTEL_PHP_OPTION_METADATA(OTEL_PHP_OPAMP_HEADERS, OptionMetadata::type::string, false),
         BUILD_OTEL_PHP_OPTION_METADATA(OTEL_PHP_OPAMP_ENDPOINT, OptionMetadata::type::string, false),

prod/native/libcommon/code/ConfigurationSnapshot.h

@@ -31,6 +31,8 @@
 
 #define OTEL_PHP_DEPENDENCY_AUTOLOADER_GUARD_ENABLED dependency_autoloader_guard_enabled
 
+#define OTEL_PHP_OPENTELEMETRY_EXTENSION_EMULATION_ENABLED opentelemetry_extension_emulation_enabled
+
 #define OTEL_PHP_NATIVE_OTLP_SERIALIZER_ENABLED native_otlp_serializer_enabled
 
 #define OTEL_PHP_OPAMP_HEADERS opamp_headers
@@ -107,6 +109,7 @@ struct ConfigurationSnapshot {
     std::chrono::milliseconds OTEL_PHP_INFERRED_SPANS_MIN_DURATION = std::chrono::milliseconds(0);
 
     bool OTEL_PHP_DEPENDENCY_AUTOLOADER_GUARD_ENABLED = false;
+    bool OTEL_PHP_OPENTELEMETRY_EXTENSION_EMULATION_ENABLED = true;
     bool OTEL_PHP_NATIVE_OTLP_SERIALIZER_ENABLED = true;
 
     std::string OTEL_PHP_OPAMP_HEADERS;

prod/php/OpenTelemetry/Instrumentation/hook.php

@@ -30,11 +30,13 @@
  *
  * @see https://github.com/open-telemetry/opentelemetry-php-instrumentation
  */
-function hook(
-    ?string $class,
-    string $function,
-    ?Closure $pre = null,
-    ?Closure $post = null,
-): bool {
-    return InstrumentationBridge::singletonInstance()->hook($class, $function, $pre, $post);
+if (!function_exists(__NAMESPACE__ . '\\hook')) {
+    function hook(
+        ?string $class,
+        string $function,
+        ?Closure $pre = null,
+        ?Closure $post = null,
+    ): bool {
+        return InstrumentationBridge::singletonInstance()->hook($class, $function, $pre, $post);
+    }
 }