poetry-pycontainer

poetry-pycontainer

A Poetry plugin that integrates pycontainer-build to build OCI container images directly from your Poetry projects — no Docker required.

Features

• 🐍 Native Poetry Integration - Build containers with poetry build-container
• 🚫 No Docker Required - Pure Python OCI image generation
• ⚡ Fast Builds - Efficient layer caching and reuse
• 🔧 Configuration via pyproject.toml - Use [tool.pycontainer] section
• 📦 Automatic Dependency Packaging - Includes Poetry dependencies
• 🔒 SBOM Generation - Built-in security compliance

Installation

poetry self add poetry-pycontainer

Or install pycontainer-build and the plugin:

pip install poetry-pycontainer pycontainer-build

Quick Start

Basic Usage

# Build a container image from your Poetry project
poetry build-container

# Build with a specific tag
poetry build-container --tag myapp:v1.0.0

# Build and push to registry
poetry build-container --tag ghcr.io/user/myapp:latest --push

Configuration

Add configuration to your pyproject.toml:

[tool.poetry]
name = "myapp"
version = "1.0.0"
description = "My Python application"

[tool.pycontainer]
tag = "myapp:latest"
base_image = "python:3.11-slim"
registry = "ghcr.io/user/myapp"
include_deps = true
push = false

[tool.pycontainer.env]
ENV = "production"
PORT = "8080"

[tool.pycontainer.labels]
maintainer = "[email protected]"

Commands

poetry build-container

Build an OCI container image from your Poetry project.

Options:

• --tag, -t - Container image tag (default: {name}:{version})
• --base-image, -b - Base container image (default: python:3.11-slim)
• --registry, -r - Container registry URL
• --push, -p - Push image to registry
• --include-deps, -d - Include Poetry dependencies (default: true)
• --sbom, -s - Generate SBOM (spdx or cyclonedx)
• --verbose, -v - Verbose output
• --dry-run - Show what would be built without building
• --no-cache - Disable layer caching

Examples:

# Basic build
poetry build-container

# Build with custom tag
poetry build-container --tag myapp:v2.0.0

# Build on different base image
poetry build-container --base-image python:3.12-alpine

# Build with SBOM
poetry build-container --sbom spdx

# Build and push to GHCR
poetry build-container \
  --tag ghcr.io/myorg/myapp:latest \
  --push \
  --verbose

# Dry run to preview
poetry build-container --dry-run --verbose

Configuration Reference

All configuration is under [tool.pycontainer] in pyproject.toml:

[tool.pycontainer]
# Container image tag (optional, defaults to {name}:{version})
tag = "myapp:latest"

# Base container image
base_image = "python:3.11-slim"

# Container registry URL
registry = "ghcr.io/user/myapp"

# Push image to registry after build
push = false

# Include Poetry dependencies in the image
include_deps = true

# Generate SBOM (spdx or cyclonedx)
sbom = "spdx"

# Enable verbose output
verbose = false

# Dry run mode
dry_run = false

# Disable layer caching
no_cache = false

# Environment variables to set in the container
[tool.pycontainer.env]
ENV = "production"
PORT = "8080"
DEBUG = "false"

# Container labels
[tool.pycontainer.labels]
maintainer = "[email protected]"
version = "1.0.0"
org.opencontainers.image.source = "https://github.com/user/repo"

How It Works

1. Reads Poetry Configuration - Extracts project name, version, dependencies from pyproject.toml
2. Applies Tool Configuration - Merges [tool.pycontainer] settings
3. Builds Container - Uses pycontainer-build to create OCI image
4. Adds Metadata - Automatically adds Poetry metadata as OCI labels
5. Pushes (Optional) - Pushes to registry if --push is specified

Integration Examples

With GitHub Actions

name: Build and Push Container

on:
  push:
    branches: [main]

jobs:
  build:
    runs-on: ubuntu-latest
    permissions:
      packages: write
    steps:
      - uses: actions/checkout@v4
      
      - uses: actions/setup-python@v5
        with:
          python-version: '3.11'
      
      - name: Install Poetry
        run: pipx install poetry
      
      - name: Install plugin
        run: poetry self add poetry-pycontainer
      
      - name: Install dependencies
        run: poetry install
      
      - name: Build and push container
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        run: |
          poetry build-container \
            --tag ghcr.io/${{ github.repository }}:${{ github.sha }} \
            --push \
            --verbose

With Azure Developer CLI

# azure.yaml
name: myapp

services:
  api:
    project: ./
    language: python
    host: containerapp
    hooks:
      prebuild:
        shell: sh
        run: |
          pip install poetry
          poetry self add poetry-pycontainer
      build:
        shell: sh
        run: |
          poetry build-container \
            --tag ${SERVICE_IMAGE_NAME}:${SERVICE_IMAGE_TAG} \
            --push

Local Development

# Install dependencies
poetry install

# Build container locally
poetry build-container --tag myapp:dev

# Test with Docker (for validation only)
docker run myapp:dev

Advanced Usage

Custom Base Images

# Use distroless for smaller images
poetry build-container --base-image gcr.io/distroless/python3-debian12

# Use Alpine for minimal size
poetry build-container --base-image python:3.11-alpine

Multi-Stage Configuration

[tool.pycontainer]
base_image = "python:3.11-slim"

[tool.pycontainer.env]
# Development
ENV = "development"

# Override in CI with --env flag or environment variables

Framework Auto-Detection

pycontainer-build automatically detects and configures:

• FastAPI - Sets up uvicorn with correct host/port
• Flask - Configures Flask development server
• Django - Sets up Django runserver

No manual configuration needed!

Troubleshooting

Plugin Not Found

# Ensure plugin is installed
poetry self show plugins

# Reinstall if needed
poetry self remove poetry-pycontainer
poetry self add poetry-pycontainer

Build Fails: "pycontainer-build not found"

# Install pycontainer-build
pip install pycontainer-build

# Or add as a dev dependency
poetry add --group dev pycontainer-build

Dependencies Not Included

Ensure include_deps = true in your config:

[tool.pycontainer]
include_deps = true

Requirements

• Python 3.11+
• Poetry 1.2.0+
• pycontainer-build (installed automatically as dependency)

License

MIT License - See LICENSE file for details

Contributing

Contributions welcome! Please see CONTRIBUTING.md for guidelines.

Related Projects

• pycontainer-build - The core container builder
• hatch-pycontainer - Hatch plugin for pycontainer-build
• Poetry - Python dependency management

Support

• GitHub Issues
• Documentation