tflowclient

The tflowclient package (Text-based workFlow scheduler Client) provides all the necessary bits to build text-based console clients to interact with various workflow schedulers. For now, only SMS is supported: see the bin/tflowclient_cdp.py executable.

The default display is a tree-view of the workload currently being managed by the workflow scheduler. An alternative display/"app" is available and can be trigger by adding `-a Cancel`` on the command-line: it allows to select several root nodes and to cancel (i.e. delete) them.

Requirements & Dependencies

The tflowclient package is only compatible with Python >= 3.7.

The tflowclient package itself only depends on the non-standard urwid package that is available on PyPi.

Developers will also need to install the pytest and black PyPi packages in order to respectively test the code and format the code.

To use the bin/tflowclient_cdp.py executable, a cdp executable needs to be available in the system's path. Otherwise, its path can be specified in the user-specific configuration file ~/.tflowclientrc.ini.

Installation

Manually

Just fetch the code and add the src directory to your PYTHONPATH.

Via pip

Install pip's build package:

pip install build

Build the tflowclient package (from the repository root directory):

python -m build

After this step, a ready to use pip package should be located in the dist subdirectory. It may be installed using pip:

pip install ./dist/package_name.tar.gz

Rules regarding developments

All the Python code (including the code in bin and tests subdirectories) must comply with PEP8. Prior to any commit in the central repository, all the Python code must be automatically formatted using the black formatter:

black .

All the unit tests must succeed at any time. The pytest launcher should be used (from the repository root directory):

pytest

The ~/.tflowclientrc.ini configuration file

The configuration file is optional. You do not need to create it unless you want to customise some the default configuration

It could look like that:

[logging]
; Activate logging in a ``~/.tflowclient.log`` file for messages with a
; severity greater or equal to ``CRITICAL``.
level = CRITICAL

[urwid]
; The backend for ``urwid``. The other possible value is ``curses``.
backend = raw

[palette]
; The platette that will be used by urwid.
; For example, you might want to print aborted tasks with black
; characters on a ``dark magenta`` background
ABORTED = black,dark magenta

The default tflowclient palette can be dumped using the bin/tflowclient_palette.py executable. More details, on the various color schemes can be obtained in the urwid documentation.

By default, only 16 colors are available to build the "palette". Some of may want to expand their horizons... Theoretically, it is possible to support 256 colors (see the configuration) but beware that it is not supported by all terminals (that's why it's not activated by default).

Use of a 256-colors palette:

[urwid]
backend = raw
terminal_colors = 256

[palette]
ABORTED = black, dark magenta, , g74, #f86

The first to entries of the palette still represent foreground and background colors for the 16-colors palette but the 4th and 5th elements represents foreground and background colors for the 256-colors palette (see https://urwid.readthedocs.io/en/latest/examples/index.html#palette-test-py).

Extra configuration for SMS/CDP

When running the tflowclient_cdp.py utility, the server name, user name and SMS suite to follow have to be specified:

tflowclient_cdp.py -s sms_server -u sms_user -r sms_suite

For a day to day use, default values can be specified in the ~/.tflowclientrc.ini file:

[cdp]
path=path_to_the_cdp_binary
host=sms_server
user=sms_user
suite=sms_suite

path may be omitted if it is properly configured system-wide.

In addition, the user must provide his credentials in a ~/.smsrc file. The ~/.smsrc file may contain several lines for each of the server_name/user_name pair the user wants to connect to. The .smsrc file looks like:

sms_server sms_user sms_user_s_password

The ~/.smsrc file needs to be accessible only by the user ("600" permissions in octal notation).