Excessive logging of `hookImplementationsMap[hook]: invalid key or value`

[richardgaunt]

Description

This started with the upgrade to 11.10.0.24 for new relic php agent

We are getting many, many (1000s) of logs during deployment:

hookImplementationsMap[hook]: invalid key or value

This log was implemented as part of: #1030

I have run a check within my code base validating the hookImplementationsMap (in ModuleHandler) but cannot see any issue with the ModuleHandler::hookImplementationsMap

See below (I may have got something wrong as the c code is not easily readable for a php developer - please let me know and I can reimplement in my code base):

protected function isValidImplementation() {
    foreach ($this->hookImplementationsMap as $hook_key => $hook_value) {
      // Remimplementing
      //      if (NULL == key || 0 == ZEND_STRING_LEN(key)
      //        || 0 == nr_php_is_zval_valid_array(val)
      //        || 0 == zend_hash_num_elements(Z_ARRVAL_P(val))) {
      //        return true;
      //      } else {
      //        return false;
      //      }

      if ($hook_key === NULL || $hook_value === '' || !is_array($hook_value) || count($hook_value) === 0) {
        return $hook_key;
      }
    }
  }

Steps to Reproduce

Deploy the server with the new relic

Expected Behavior

Should not be getting these logs.

Relevant Logs / Console output

warning: hookImplementationsMap[hook]: invalid key or value

Your Environment

We are utilising this image (note the new relic download and installation):

https://github.com/uselagoon/lagoon-images/blame/main/images/php-fpm/8.3.Dockerfile

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[bduranleau-nr]

Hi @richardgaunt! Thank you for your report, I'm sorry you're experiencing this issue.

I'm surprised you're getting this warning message, since it should just be checking for valid key/value pairs in the Drupal-defined hookImplementationsMap. I ran some tests today to try and reproduce the issue you're seeing on the Drupal umami demo site and wasn't able to get any warning outputs like you're seeing on your end. I'd like to investigate a little further, if you don't mind providing some details about your environment.

Looking at your testing function:

      if ($hook_key === NULL || $hook_value === '' || !is_array($hook_value) || count($hook_value) === 0) {
        return $hook_key;
      }

Since we check for $hook_key == NULL in this conditional, we don't want to return $hook_key if that check passes. I would suggest tweaking this logic to print out an error log message if it occurs, with details of what conditional specifically failed if possible (it may be best to split up the if statement in that case, with one check for the key and another for the value). The $hook_key should be a non-empty string, whereas the $hook_value should be a non-empty array. Would it be possible to print out the entire contents of the $hookImplementationsMap on your application and check for any key/value pair violations that don't match those expectations, and share any you may find here?

One thing I noticed looking at the lagoon link you provided is that in addition to the New Relic PHP Agent, that image also installs blackfire here: https://github.com/uselagoon/lagoon-images/blob/1318994bd59dd394058a5b8ecb0fce2f70398b34/images/php-fpm/8.3.Dockerfile#L153. Blackfire is another APM agent. We know from experience that systems with multiple APM solutions installed can step on each other's toes in unexpected ways, and officially recommend disabling other 3rd party APM software when using the New Relic PHP Agent. Can you confirm if you are using Blackfire in your setup? If so, can you try disabling it and seeing if the issue persists?

If you have any security concerns providing any of the above in Github, let me know and I can direct you towards resources that will get you in touch with our General Tech Support Engineers, who will be able to work with you directly and securely to gather environment information, logs, etc privately for further debugging.

[richardgaunt]

Yes amended the checking function - ran it in the constructor of ModuleHandler and no violations.

  /**
   * Added checks to test new relic logging.
   *
   * @return void
   */
  protected function validateImplementationMapHooks(): void {
    foreach ($this->hookImplementationsMap as $hook_key => $hook_value) {
      if ($hook_key === NULL) {
        \Drupal::service('logger.factory')->get('Extension')->error('hookImplementationsMap: The hook implementation map contains a NULL key.');
      }
      if ($hook_value === '' || !is_array($hook_value) || count($hook_value) === 0) {
        \Drupal::service('logger.factory')->get('Extension')->error(sprintf('hookImplementationsMap: The hook %s has invalid value', $hook_key));
      }
    }
  }

I am still getting 1000s of logs - this is happening when Drupal bootstraps. I will let you know if i notice anything else from the logs.

[richardgaunt]

Might be good for the new relic agent to specify which entry it found to be invalid

[richardgaunt]

I can confirm that blackfire is installed but not activated on our setup

[zsistla]

Thank you for your feedback. This issue has been addressed in the latest New Relic PHP Agent Release 12.0.0.25. Logging has been modified to reduce the number of logs and to provide more information on the error condition.

[seanhamlin]

Just noting that this issue I do not consider resolved. We updated to 12.0.0.25 and still see loads of

2025-08-26 14:00:14.888 +0000 (95 95) warning: hookImplementationsMap[hook]: invalid key

Editing /usr/local/etc/php/conf.d/newrelic.ini to set

newrelic.loglevel = "error"
newrelic.daemon.loglevel = "error"

Stopped the warning spam we were receiving.

[richardgaunt]

The logging is saying one of the keys is NULL or invalid string.

I patched drupal and created validation of this variable in the ModulHandler class to test this variable directly and there is nothing wrong with the variable.

This logging appears to happen on cache rebuild (drush cr) and on cron when I assume the container is rebuilt but even when I validated this variable at those times there were no errors.