Google Stackdriver php-fpm curl_json plugin example

readme.md

Description

Google Stackdriver has various plugins for metrics on third-party applications. Looking for an integration with php-fpm, I came across this thread: https://groups.google.com/g/google-stackdriver-discussion/c/_okXG7SYqGg

While there was a mention of success, there was no description, example or explanation. I set out to find a solution myself and want to share that here.

The end-result is basically a combination of a CollectD example for php-fpm with the example in the Stackdriver documents for custom metrics using Nginx

Note: in order for the stackdriver-agent to gather stats on your php-fpm installation, the path needs to be exposed by the webserver. I used Apache2 (example attached), but something similar can be easily achieved with Nginx as well.

local.conf

<VirtualHost *:80>
  ServerName _
  ServerAlias localhost 127.0.0.1 local-stackdriver-agent.stackdriver.com

  <LocationMatch "/_php/status">
    Order Allow,Deny
    Allow from 127.0.0.1
    ProxyPass "unix:/var/run/php/php5.6-fpm.sock|fcgi://localhost/_php/status"
  </LocationMatch>

  DocumentRoot /var/www/html/

  <Directory /var/www/html>
    Options -Indexes +FollowSymLinks +MultiViews
    AllowOverride All
    Order allow,deny
    Allow from all
  </Directory>

  SetEnvIf Remote_Addr "::1" loopback
  SetEnvIf Remote_Addr "127\.0\.0\.1" loopback

  ErrorLog /var/log/apache2/health.log
  LogLevel warn
  CustomLog /dev/null combined
</VirtualHost>

phpfpm_curl_json.conf

LoadPlugin curl_json
<Plugin curl_json>
<URL "http://127.0.0.1/_php/status?json">
 Instance "phpfpm"
 <Key "accepted conn">
     Type "derive"
     Instance "accepted_connections"
 </Key>
 <Key "slow requests">
     Type "derive"
     Instance "slow_requests"
 </Key>
 <Key "listen queue">
     Type "gauge"
     Instance "listen_queue"
 </Key>
 <Key "active processes">
     Type "gauge"
     Instance "active_processes"
 </Key>
 <Key "idle processes">
     Type "gauge"
     Instance "idle_processes"
 </Key>
 <Key "total processes">
     Type "gauge"
     Instance "total"
 </Key>
 <Key "max active processes">
     Type "gauge"
     Instance "max_active"
 </Key>
</URL>
</Plugin>

LoadPlugin match_regex
LoadPlugin target_set
LoadPlugin target_replace

PreCacheChain "PreCache"
<Chain "PreCache">
  <Rule "jump_to_custom_metrics_from_curl_json">
    <Match regex>
      Plugin "^curl_json$"
      PluginInstance "^phpfpm$"
    </Match>
    <Target "jump">
      Chain "PreCache_curl_json"
    </Target>
  </Rule>
</Chain>
<Chain "PreCache_curl_json">
  <Rule "rewrite_curl_json_phpfpm">
    <Match regex>
      Plugin "^curl_json$"                   # Match on plugin.
      PluginInstance "^phpfpm.*$" # Match on plugin instance.
    </Match>
    <Target "set">
      MetaData "stackdriver_metric_type" "custom.googleapis.com/phpfpm/%{type_instance}"
      MetaData "label:service_name" "%{plugin_instance}"
    </Target>
    <Target "replace">
      MetaData "label:service_name" "phpfpm_" ""
    </Target>
  </Rule>

  <Rule "go_back">
    Target "return"
  </Rule>
</Chain>