The goal of this issue is to let Piwik Super Users configure a custom JavaScript snippet of code that would automatically be appended to the/piwik.js tracking code served by the Piwik tracking server(s).

Proposed solution

• we build a new plugin "CustomPiwikJs"
• this plugin would be open source and available in the Marketplace,
• Super User can enter a JS code snippet in the CustomPiwikJs plugin setting Textarea,
• the plugin defines a new console command that when executed will:
  • generate a new piwik.js appending any custom script,
  • if the generated piwik.js is different from the original /piwik.js
  • then overwrite the /piwik.js file.
• appending JS script to piwik.js could be easily made available to
  other plugins via a hook.
  • This would lead to amazing potential for plugins to customise the tracking code served by Piwik to the websites and web apps!
  • eg. plugin Heatmap Heatmap plugin for Piwik + Click + Scroll maps #6371 could require CustomPiwikJs plugin and then insert custom JS tracker to store mouse positions and build heatmaps

Notes

• this logic would be executed as schedule task every 5 min or so if possible, and also once after each Piwik Upgrade.
• to make sure our sync task runs really every 5 min, we will need to setup a cron for user to execute this command every 5 minutes:
  core:run-scheduled-tasks Will run all scheduled tasks due to run at this time.
• (if the last scheduled task ran more than N min ago, display a warning message notification that file may be out of sync)

feel free to post if you have any feedback!