diff --git a/Doc/howto/logging-cookbook.rst b/Doc/howto/logging-cookbook.rst index ae101e3cdf2..bf6f54a841a 100644 --- a/Doc/howto/logging-cookbook.rst +++ b/Doc/howto/logging-cookbook.rst @@ -765,13 +765,71 @@ serialization. Running a logging socket listener in production ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ -To run a logging listener in production, you may need to use a process-management tool -such as `Supervisor `_. `Here -`_ is a Gist which -provides the bare-bones files to run the above functionality using Supervisor: you -will need to change the ``/path/to/`` parts in the Gist to reflect the actual paths you -want to use. +.. _socket-listener-gist: https://gist.github.com/vsajip/4b227eeec43817465ca835ca66f75e2b +To run a logging listener in production, you may need to use a +process-management tool such as `Supervisor `_. +`Here is a Gist `__ +which provides the bare-bones files to run the above functionality using +Supervisor. It consists of the following files: + ++-------------------------+----------------------------------------------------+ +| File | Purpose | ++=========================+====================================================+ +| :file:`prepare.sh` | A Bash script to prepare the environment for | +| | testing | ++-------------------------+----------------------------------------------------+ +| :file:`supervisor.conf` | The Supervisor configuration file, which has | +| | entries for the listener and a multi-process web | +| | application | ++-------------------------+----------------------------------------------------+ +| :file:`ensure_app.sh` | A Bash script to ensure that Supervisor is running | +| | with the above configuration | ++-------------------------+----------------------------------------------------+ +| :file:`log_listener.py` | The socket listener program which receives log | +| | events and records them to a file | ++-------------------------+----------------------------------------------------+ +| :file:`main.py` | A simple web application which performs logging | +| | via a socket connected to the listener | ++-------------------------+----------------------------------------------------+ +| :file:`webapp.json` | A JSON configuration file for the web application | ++-------------------------+----------------------------------------------------+ +| :file:`client.py` | A Python script to exercise the web application | ++-------------------------+----------------------------------------------------+ + +The web application uses `Gunicorn `_, which is a +popular web application server that starts multiple worker processes to handle +requests. This example setup shows how the workers can write to the same log file +without conflicting with one another --- they all go through the socket listener. + +To test these files, do the following in a POSIX environment: + +#. Download `the Gist `__ + as a ZIP archive using the :guilabel:`Download ZIP` button. + +#. Unzip the above files from the archive into a scratch directory. + +#. In the scratch directory, run ``bash prepare.sh`` to get things ready. + This creates a :file:`run` subdirectory to contain Supervisor-related and + log files, and a :file:`venv` subdirectory to contain a virtual environment + into which ``bottle``, ``gunicorn`` and ``supervisor`` are installed. + +#. Run ``bash ensure_app.sh`` to ensure that Supervisor is running with + the above configuration. + +#. Run ``venv/bin/python client.py`` to exercise the web application, + which will lead to records being written to the log. + +#. Inspect the log files in the :file:`run` subdirectory. You should see the + most recent log lines in files matching the pattern :file:`app.log*`. They won't be in + any particular order, since they have been handled concurrently by different + worker processes in a non-deterministic way. + +#. You can shut down the listener and the web application by running + ``venv/bin/supervisorctl -c supervisor.conf shutdown``. + +You may need to tweak the configuration files in the unlikely event that the +configured ports clash with something else in your test environment. .. _context-info: