5. Use Python for scripting inside and outside containers#

Date: 2022-11-30

Status#

Accepted

Context#

Inside the container, we use the ibek tool for scripting. Outside we use ec from epics-containers-cli.

Much of what these tools do is call command line tools like docker, helm, kubectl, compilers, etc. This seems like a natural fit for bash scripts.

These features were originally implemented in bash but were converted to python for the following reasons:

python provides for much richer command line arguments
it is also much easier to provide rich help
managing errors is vastly improved with exception handling
the unit testing framework allows good test coverage in continuous integration
complex string handling is a common requirement and is much easier in python
there is a clear versioning strategy and packages can be installed with pip, meaning that you can check which version of the script you are running and report bugs against a specific version
the code is much easier to read and maintain
because the packages can be pip installed they can be used in CI and inside multiple containers without having to copy the scripts around

Decision#

We always prefer Python and keep bash scripts to a minimum

Consequences#

Scripting is much easier to maintain and is more reliable.