ps.basic

The ps (Production System) packages implementation started in 2013. Given a non staged production environment - hosted on different operating Systems all around the globe the implementations first goal was to consolidate the widely spread scripts and standalone Programs - started via cron - under one umbrella. At that time it was decided to implement that umbrella using python 2.4. The ps.basic package was created.

Back than the ps.basic requirements where:

• establish the usage of templates for shell scripts and emails

• establish a consistent way calling shell scripts and sending emails

• establish a consistent way for local logging (with automatic logfile rotation/deletion)

• establish a consistent way to handle configuration files

• establish a consistent way to handle staged environments (TESTING/DEVELOPMENT/INTEGRATION/PRODUCTION)

In the next step it was decided to:

• enhance the logging

  • additionally send the logging message to a network socket endpoint

  • enhance the logging message with version number, Product_id, ….

  • implement a program/package ps_bridge being able to receive those logging messages

    • to store those logging messages in an sqlite database (as delivered with the python standard distribution)

    • or/and route those logging messages to further destinations

  • implement a web server ps_herald to analyze the logging messages provided by the sqlite database on a node

  • implement a tool in that package ps_neelix to react on

    • logging messages e.g inform interested parties that something happened e.g using email via stage_specific configuration files (easily added to versioning control)

    • lost heartbeats of monitored services putting their logging messages in the sqlite database on a node

• add a finite state machine environment to the ps.basic package

  • easing putting structure to the implementation

  • a graphical representation based on pygraphviz was added - generating the image from the implementation.

Those mechanisms where implemented compatible to python 2.4. Having a package major version numbers 0 e.g. 0.x.x and are used in daily production.

It allows for a staged development/production environment - combined with CI/CT … allowing to easily monitor the distributed services behaviour and configuration - as depicted in the following picture.

Crucial points for the logging are:

• the used network connections are setup using ssh where the setup of the connection is completely owned by the “mother company” - it is currently not in the scope of the project to further manage this

• that the Version number of the service (beside module name , line number …) is automatically integrated into the logging message - serving Requirements for ITIL.

• it is possible (and used in production) to (easily) extend existing applicacitions to use the (version based) logging mechanism.

Starting with the usage of python 3 the package was released to the public using a major version number 1 e.g. 1.x.x.

Documentation: https://psbasic.readthedocs.io

Git: https://bitbucket.org/drsetz/ps.basic/src/master/