Common CLI behavior

[woutdenolf]

Two new modules for common behavior across all PyMca applications:

• PyMca5.PyMcaGui.PyMcaAppInit: common behavior for multiprocessing, Qt, HDF5, matplotlib, logging.
  Common calls at these stages of the application start-up:
  • before importing application dependencies
  • after importing application dependencies and before instantiating the application
  • after instantiating and before starting the application
• PyMca5.PyMcaMisc.CliUtils: common CLI behavior in terms of logging, common arguments.
  Uses argparse instead of getopt which provides proper --help for users.

The docstring of the two modules show the usage pattern.

Currently we have 28 CLI's of which 20 are Qt apps. There are many more files with a __main__, many of which using sys.argv directly, but I only handled the once that already had a CLI by using getopt or argparse.

In addition I added unit tests for the CLI: python -m PyMca5.tests.CliTest

Main CLI as an example

pymca --help

usage: pymca [-h] [--debug DEBUG] [--log-level {DEBUG,INFO,WARNING,ERROR,CRITICAL}] [--version] [--qt {5,6}]
             [--binding {pyqt5,pyqt6,pyside2,pyside6}]
             [--backend {matplotlib,mpl,gl,opengl,glut,osmesa,mesa,silx,silx-mpl,silxmpl,silx-gl,silxgl}]
             [--spec SPEC] [--shm SHM] [--fresh] [--nativefiledialogs NATIVEFILEDIALOGS] [--profiling] [--test]
             [files ...]

Main PyMca GUI

positional arguments:
  files                 Optional list of data files to open (default: None)

options:
  -h, --help            show this help message and exit
  --debug DEBUG         Enable debug mode (default: 0)
  --log-level {DEBUG,INFO,WARNING,ERROR,CRITICAL}
                        Logging level (default: WARNING)
  --version             Show version and exit (default: False)
  --qt {5,6}            Force Qt version (default: None)
  --binding {pyqt5,pyqt6,pyside2,pyside6}
                        Qt binding (default: None)
  --backend {matplotlib,mpl,gl,opengl,glut,osmesa,mesa,silx,silx-mpl,silxmpl,silx-gl,silxgl}
                        The plot backend to use: Matplotlib, OpenGL 2.1 (requires appropriate OpenGL drivers),
                        or Off-screen Mesa OpenGL software pipeline (requires OSMesa library). (default: mpl)
  --spec SPEC           Spec file (default: None)
  --shm SHM             Shared memory spec (default: None)
  --fresh, -f           Clear configuration (default: False)
  --nativefiledialogs NATIVEFILEDIALOGS
                        Use native file dialogs (default: 0)
  --profiling           Run main loop under profiler (default: False)
  --test                Run unit tests (default: False)