doc/admin-guide/plugins/hook-trace.en.rst

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.. include:: ../../common.defs

.. _admin-plugins-hook-trace:

Hook Trace Plugin
*****************

The HookTrace plugins shows the fundamental set of hooks that are
commonly used by plugins. It is also useful for tracing the sequence
of hook calls a plugin can receive under different circumstances.

The plugin begins by adding a global hook on each of the hooks it
is interested in. Next, in the event handler, we simply cast the
event data pointer to the expected type.

Hook events can be shown in the |TS| diagnostic log by using the
``hook-trace`` diagnostic tag::

    $ traffic_server -T hook-trace

.. literalinclude:: ../../../plugins/experimental/hook-trace/hook-trace.cc
   :language: c
   :lines: 24-