Development Notes

Development Notes#

Start Development Environment#

The project is designed fot Visual Studio Code development environment.

  1. Start VSCODE.

  2. Press Ctrl + Shift + P and search for Dev Containers: Open Folder in Container… and click on it.

  3. Select dev env, either PyTorch.

Programming Principles#

Parameters Validation#

It is assumed that all functions and class methods follow precondition principle, specifically demanding approach. Demanding approach states, that part of function or class method logic should be a pre-section which does the validation of all input parameters and prevents code to be injected by wrong arguments. This also offloads the responsibility from user to the function / class method itself.

Python Guidelines#

Max Line Length: It is set to 150 characters.

Commits Validation#

Every commit has to pass through and be compliant with following tools:

  • Ruff (linter & formatter)

  • PyRight (type check)

  • Bandit (vulnerabilities check)

The default configuration/standards of the tools is slightly modified generally and occasionally, there is a particular PEP message disabling on a line level in the code.

Tools could be installed manually by a user or using pre-commit tool which integrates all the tools. This is also the preferred way. See Project Installation for more details about pre-commit installation and location of modified configuration files.

Docstring#

It is used Google format.

To improve docstring readability, following highlight types are assumed:

  • <>: Used to highlight <variable>, <class>, <class.method()>, <class.attribute>, <function()>, etc…

  • **: Used to highlight Metron’s modules (e.g. *Video Streamer*) and terms to emphasize that wording represents a specific solution’s piece.

  • ``: Used to highlight source code blocks and commands ( e.g. `from metron_conduit.source_connector import *`), values (e.g. `-1`, `1.44` or `"string_value"`) or paths (e.g. `docs/images`).

Python Dependencies#

uv package manager is used.

YAML Configs#

Comments#

YAML comments convention should follow Python docstring convention.

Config Values Validation#

Metron does not use any main all YAML config parameters validation routine. Hydra does validation of expected config parameters and their type. In the code, configuration variable is accessed whenever is needed using specific decorator, applied on a function or class method. It passes the configuration variable as the first parameter in the function / class method. Therefore, the same principle as in Parameters Validation is followed. The function / class method has to validate required config parameter values and if the requirements are not met, raise ValueError with custom message referring to the particular YAML config parameter.

Diagram Drawings#

All Metron diagrams are drawn using diagrams.net tool. Diagram projects are found in docs/diagram_projects.

Design#

Colour Palette#

The colour palette is given by following colours:

  • orange: #F9895C

  • blue: #65BCD8

  • yellow: #F8D643

  • dark grey: #545A5E

Fonts#

As a theme font, QUANTUM (download link) font is used. This font should be used for visually appealing diagrams or headlines.

Tahoma is used as a standard font everywhere else.

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