Configure Formatter and Linter for a Python Dev Container using VSCode

devcontainer.json

// For format details, see https://aka.ms/devcontainer.json. For config options, see the
// README at: https://github.com/devcontainers/templates/tree/main/src/docker-in-docker
{
    "name": "Python Dev Container w/ Linter & Formatter",
    "image": "mcr.microsoft.com/devcontainers/base:bullseye",
    "postCreateCommand": {
        "installLint": "pip install flake8",
        "installFormatter": "pip install black",
        "installDeps": "pip install -r ${containerWorkspaceFolder}/app/requirements.txt",
        "installApp": "pip install -e ${containerWorkspaceFolder}/"
    },
    "features": {
        "ghcr.io/devcontainers/features/docker-in-docker:2": {
            "version": "latest",
            "enableNonRootDocker": "true",
            "moby": "true"
        },
        "ghcr.io/devcontainers/features/python:1": {}
    },
    "customizations": {
        // Configure properties specific to VS Code.
        "vscode": {
            // Set *default* container specific settings.json values on container create.
            "settings": {
                "python.formatting.provider": "black",
                "editor.detectIndentation": false,
                "editor.formatOnSave": true,
                "editor.insertSpaces": true,
                "editor.tabSize": 4,
                "python.linting.flake8Enabled": true,
                // https://black.readthedocs.io/en/stable/the_black_code_style/current_style.html#line-length
                "python.linting.flake8Args": [
                    "--ignore=E203",
                    "--max-line-length=88"
                ]
            },
            // Add the IDs of extensions you want installed when the container is created.
            "extensions": [
                "ms-python.python"
            ]
        }
    },
    // Set container env variables as desired
    "remoteEnv": {}
}

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// this installs formatter,linter before installing the project dependancies.
...
"postCreateCommand": {
    "installLint": "pip install flake8",
    "installFormatter": "pip install black",
    "installDeps": "pip install -r ${containerWorkspaceFolder}/app/requirements.txt",
    "installApp": "pip install -e ${containerWorkspaceFolder}/"
},
...

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// This part is for specifying how tools operate
...
"customizations": {
    "vscode": {
        "settings": {
            "python.formatting.provider": "black",
            "editor.detectIndentation": false,
            "editor.formatOnSave": true,
            "editor.insertSpaces": true,
            "editor.tabSize": 4,
            "python.linting.flake8Enabled": true,
            // https://black.readthedocs.io/en/stable/the_black_code_style/current_style.html#line-length
            "python.linting.flake8Args": ["--ignore=E203", "--max-line-length=88"]
        },
    ...
    }
},
...