Hooks Viewer

update: README.md

Major rewrite. The plugin now covers (almost) every event Matomo dispatches and renders them inline at their dispatch point.

Hook discovery

New HookCatalog scans core/ and plugins/ for every Piwik::postEvent('…') call site. Same-file self::FOO_EVENT constants are resolved automatically.
Result is cached in tmp/cache/hooksviewer-catalog.php and rebuilt whenever the source tree changes (mtime-based signature, 5 min TTL).
~258 events discovered out of the box on a clean Matomo 5 install, vs. ~210 in the previous hand-maintained list.

Rendering

Events are rendered at the moment they fire, inline in the DOM, as <details><summary>HookName</summary><pre><code>args…</code></pre></details>.
Args are pretty-printed across multiple indented lines (depth-limited, truncated at 30 entries per level / 240 chars per string), so deep arrays and objects stay readable.
Args panel is locked to a dark background with white text so it remains legible regardless of the active Matomo theme.

Safety

Inline emission is suppressed for JSON, XML, CSV, image, and tracker responses — Matomo's API and matomo.php payloads stay byte-exact.
Widget AJAX requests (format=html) keep their inline output, so hooks like ViewDataTable.filterViewDataTable, Visualization.beforeRender, Metrics.isLowerValueBetter, and Widget.filterWidgets are visible inside each widget as it loads.
Every fired hook (HTML or not) is also appended to tmp/logs/hooksviewer.log with timestamp, request id, and args. Watch with tail -f.
Activation/deactivation now flushes Matomo's merged-asset bundle so the plugin's stylesheet is picked up immediately.

Internals

One generic __call() dispatcher replaces 200+ hand-rolled stub methods. The whole plugin is ~340 lines of PHP.
Compatible with Matomo 5.x.

Initial plugin commit.

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