Add PHP APC support (#23)

Author: Gavin M. Roy

README.md

@@ -4,6 +4,7 @@ newrelic_plugin_agent
 An agent that polls supported backend systems and submits the results to the
 NewRelic platform. Currently supported backend systems are:
 
+- Alternative PHP Cache
 - Apache HTTP Server
 - CouchDB
 - Edgecast CDN "Realtime" API
@@ -15,6 +16,7 @@ NewRelic platform. Currently supported backend systems are:
 - RabbitMQ
 - Redis
 - Riak
+- uWSGI
 
 IMPORTANT
 ---------
@@ -102,6 +104,10 @@ You can also use a single mapping like follows:
 
 The fields for plugin configurations can vary due to a plugin's configuration requirements. The name value in each stanza is only required when using multiple targets in a plugin. If it is only a single target, the name will be taken from the server's hostname.
 
+APC Installation Notes
+----------------------
+Copy the apc-php.php script to a directory that can be served by your web server or php-fpm application. Edit the newrelic_plugin_agent configuration to point to the appropriate URL.
+
 Apache HTTPd Installation Notes
 -------------------------------
 Enable the HTTPd server status page in the default virtual host. The following example configuration snippet for Apache HTTPd 2.2 demonstrates how to do this:
@@ -290,6 +296,15 @@ Configuration Example
           port: 6000
           user: stats
 
+      php_apc:
+         scheme: http
+         host: localhost
+         port: 80
+         path: /apc-nrp.php
+         #username: foo
+         #password: bar
+         #verify_ssl_cert: t
+
       postgresql:
         - host: localhost
           port: 5432

etc/apc-php.php

@@ -0,0 +1,8 @@
+<?php
+/**
+ * PHP APC Data for NewRelic Plugin Agent
+ *
+ */
+Header('Content-Type: application/json');
+echo json_encode(array('user_stats' => apc_cache_info('user', true),
+                       'shared_memory' => apc_sma_info(true)));

etc/newrelic/newrelic_plugin_agent.cfg

@@ -5,107 +5,115 @@ Application:
   poll_interval: 60
   #proxy: http://localhost:8080
 
-  #apache_httpd:
-  #  name: hostname
-  #  scheme: http
-  #  host: localhost
-  #  verify_ssl_cert: true
-  #  port: 80
-  #  path: /server-status
-
-  #couchdb:
-  #  name: localhost
-  #  host: localhost
-  #  verify_ssl_cert: true
-  #  port: 5984
-  #  username: foo
-  # password: bar
-
-  #edgecast:
-  #  name: My Edgecase Account
-  #  account: YOUR_ACCOUNT_#
-  #  token: YOUR_API_TOKEN
-
-  #memcached:
-  #  name: localhost
-  #  host: localhost
-  #  port: 11211
-  #  path: /path/to/unix/socket
-
-  #mongodb:
-  #  name: hostname
-  #  host: localhost
-  #  port: 27017
-  #  databases:
-  #    - test
-  #    - yourdbname
-
-  #mongodb:   # With Authentication
-  #  name: hostname
-  #  host: localhost
-  #  port: 27017
-  #  admin_username: user
-  #  admin_password: pass
-  #  databases:
-  #    test:
-  #      username: user
-  #      password: pass
-  #    yourdbname:
-  #      username: user
-  #      password: pass
-
-  #nginx:
-  #  name: hostname
-  #  host: localhost
-  #  port: 80
-  #  verify_ssl_cert: true
-  #  path: /nginx_stub_status
+  # apache_httpd:
+  #   name: hostname
+  #   scheme: http
+  #   host: localhost
+  #   verify_ssl_cert: true
+  #   port: 80
+  #   path: /server-status
+
+  # couchdb:
+  #   name: localhost
+  #   host: localhost
+  #   verify_ssl_cert: true
+  #   port: 5984
+  #   username: foo
+  #   password: bar
+
+  # edgecast:
+  #   name: My Edgecase Account
+  #   account: YOUR_ACCOUNT_#
+  #   token: YOUR_API_TOKEN
+
+  # memcached:
+  #   name: localhost
+  #   host: localhost
+  #   port: 11211
+  #   path: /path/to/unix/socket
+
+  # mongodb:
+  #   name: hostname
+  #   host: localhost
+  #   port: 27017
+  #   databases:
+  #     - test
+  #     - yourdbname
+
+  # mongodb:   # With Authentication
+  #   name: hostname
+  #   host: localhost
+  #   port: 27017
+  #   admin_username: user
+  #   admin_password: pass
+  #   databases:
+  #     test:
+  #       username: user
+  #       password: pass
+  #     yourdbname:
+  #       username: user
+  #       password: pass
+
+  # nginx:
+  #   name: hostname
+  #   host: localhost
+  #   port: 80
+  #   verify_ssl_cert: true
+  #   path: /nginx_stub_status
 
   # pgbouncer:
   #   host: localhost
   #   port: 6000
   #   user: stats
 
+  # php_apc:
+  #   name: hostname
+  #   scheme: http
+  #   host: localhost
+  #   verify_ssl_cert: true
+  #   port: 80
+  #   path: /apc-nrp.php
+
   # postgresql:
   #   host: localhost
   #   port: 5432
   #   user: postgres
   #   dbname: postgres
   #   superuser: False
 
-  #rabbitmq:
-  #  name: rabbitmq@localhost
-  #  host: localhost
-  #  port: 15672
-  #  verify_ssl_cert: true
-  #  username: guest
-  #  password: guest
-  #  detailed: False
-  #  resolve_dns: False
-
-  #redis:
-  #  - name: localhost
-  #    host: localhost
-  #    port: 6379
-  #    db_count: 16
-  #    password: foo # [OPTIONAL]
-  #  - name: localhost
-  #    host: localhost
-  #    port: 6380
-  #    db_count: 16
-  #    password: foo # [OPTIONAL]
-
-  #riak:
-  #  name: localhost
-  #  host: node0.riak0.scs.mtmeprod.net
-  #  verify_ssl_cert: true
-  #  port: 8098
-
-  #uwsgi:
-  #  name: localhost
-  #  host: localhost
-  #  port: 1717
-  #  path: /path/to/unix/socket
+  # rabbitmq:
+  #   name: rabbitmq@localhost
+  #   host: localhost
+  #   port: 15672
+  #   verify_ssl_cert: true
+  #   username: guest
+  #   password: guest
+  #   detailed: False
+  #   resolve_dns: False
+
+  # redis:
+  #   - name: localhost
+  #     host: localhost
+  #     port: 6379
+  #     db_count: 16
+  #     password: foo # [OPTIONAL]
+  #   - name: localhost
+  #     host: localhost
+  #     port: 6380
+  #     db_count: 16
+  #     password: foo # [OPTIONAL]
+
+  # riak:
+  #   name: localhost
+  #   host: node0.riak0.scs.mtmeprod.net
+  #   verify_ssl_cert: true
+  #   port: 8098
+
+  # uwsgi:
+  #   name: localhost
+  #   host: localhost
+  #   port: 1717
+  #   path: /path/to/unix/socket
 
 Daemon:
   user: newrelic

newrelic_plugin_agent/agent.py

@@ -263,6 +263,12 @@ def start_plugin_polling(self):
                 self.poll_plugin(plugin, pgbouncer.PgBouncer,
                                  self.application_config.get(plugin))
 
+            elif plugin == 'php_apc':
+                if 'php_apc' not in globals():
+                    from newrelic_plugin_agent.plugins import php_apc
+                self.poll_plugin(plugin, php_apc.APC,
+                                 self.application_config.get(plugin))
+
             elif plugin == 'postgresql':
                 if 'postgresql' not in globals():
                     from newrelic_plugin_agent.plugins import postgresql

newrelic_plugin_agent/plugins/php_apc.py

@@ -0,0 +1,104 @@
+"""
+PHP APC Support
+
+"""
+import logging
+import requests
+import time
+
+from newrelic_plugin_agent.plugins import base
+
+LOGGER = logging.getLogger(__name__)
+
+class APC(base.Plugin):
+
+    GUID = 'com.meetme.newrelic_php_apc_agent'
+
+    def add_datapoints(self, stats):
+        """Add all of the data points for a node
+
+        :param str stats: The stats content from APC as a string
+
+        """
+        shared_memory = stats.get('shared_memory', dict())
+        self.add_gauge_value('Shared Memory/Available', 'Bytes',
+                             shared_memory.get('avail_mem', 0))
+        self.add_gauge_value('Shared Memory/Segment Size', 'Bytes',
+                             shared_memory.get('seg_size', 0))
+        self.add_gauge_value('Shared Memory/Segment Count', '',
+                             shared_memory.get('num_seg', 0))
+
+        user_stats = stats.get('user_stats', dict())
+        self.add_gauge_value('User Cache/Slots', '',
+                             user_stats.get('num_slots', 0))
+        self.add_gauge_value('User Cache/Entries', '',
+                             user_stats.get('num_entries', 0))
+        self.add_gauge_value('User Cache/Size', 'Bytes',
+                             user_stats.get('mem_size', 0))
+        self.add_gauge_value('User Cache/Expunges', '',
+                             user_stats.get('expunges', 0))
+
+        hits = user_stats.get('num_hits', 0)
+        misses = user_stats.get('num_misses', 0)
+        total = hits + misses
+        if total > 0:
+            effectiveness = float(float(hits) / float(total)) * 100
+        else:
+            effectiveness = 0
+        self.add_gauge_value('User Cache/Effectiveness', '%', effectiveness)
+
+        self.add_derive_value('User Cache/Hits', '', hits)
+        self.add_derive_value('User Cache/Misses', '', misses)
+        self.add_derive_value('User Cache/Inserts', '',
+                              user_stats.get('num_inserts', 0))
+
+    @property
+    def apc_stats_url(self):
+        if 'scheme' not in self.config:
+            self.config['scheme'] = 'http'
+        return '%(scheme)s://%(host)s:%(port)s%(path)s?auto' % self.config
+
+    def fetch_data(self):
+        """Fetch the data from the APC script
+
+        :rtype: str
+
+        """
+        kwargs = {'url': self.apc_stats_url,
+                  'verify': self.config.get('verify_ssl_cert', True)}
+        if 'username' in self.config and 'password' in self.config:
+            kwargs['auth'] = (self.config['username'], self.config['password'])
+
+        try:
+            response = requests.get(**kwargs)
+        except requests.ConnectionError as error:
+            LOGGER.error('Error polling APC Stats: %s', error)
+            return {}
+
+        if response.status_code == 200:
+            try:
+                return response.json()
+            except Exception as error:
+                LOGGER.error('JSON decoding error: %r', error)
+                return ''
+        LOGGER.error('Error response from %s (%s): %s', self.apc_stats_url,
+                     response.status_code, response.content)
+        return ''
+
+    def poll(self):
+        LOGGER.info('Polling APC Stats via %s', self.apc_stats_url)
+        start_time = time.time()
+        if 'scheme' not in self.config:
+            self.config['scheme'] = 'http'
+        self.derive = dict()
+        self.gauge = dict()
+        self.rate = dict()
+        data = self.fetch_data()
+        if data:
+            self.add_datapoints(data)
+            LOGGER.info('Polling complete in %.2f seconds',
+                        time.time() - start_time)
+        else:
+            LOGGER.error('No data was returned from APC. Ensure '
+                         'configuration is correct and that %s is reachable '
+                         'by the agent', self.apc_stats_url)