Harden Dockerfile for production: pin, freeze, drop runtime uv#98
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brandonros wants to merge 3 commits into
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Harden Dockerfile for production: pin, freeze, drop runtime uv#98brandonros wants to merge 3 commits into
brandonros wants to merge 3 commits into
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The previous Dockerfile was a dev setup masquerading as production: - `FROM python:latest` meant rebuilds drifted silently over time. - `uv sync --locked` + `uv run` at CMD meant every container start re-validated the lockfile against the venv, which can touch the package index (at minimum DNS) even when the venv is already built. - `--reload` is uvicorn's dev mode; it watches the filesystem and respawns workers, each of which re-invokes the CMD and compounds the above. This rewrite: - Pins the base image (python:3.12-slim) and uv (0.4.30) so builds are reproducible. - Uses a multi-stage build so the runtime image ships neither uv nor pip caches. - Switches `--locked` -> `--frozen` so lockfile drift fails the build loudly instead of being silently reconciled. - Splits the dep-install layer from the source-copy layer so code changes don't bust the dependency cache. - Drops `uv run` from CMD and invokes uvicorn directly from /app/.venv/bin via PATH. Runtime startup now makes zero PyPI callouts and needs no DNS for package management. - Removes `--reload`. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Without these env vars, `uv sync` downloads its own CPython into /root/.local/share/uv/python/ and symlinks the venv's interpreter to it. In a multi-stage build we only COPY /app across, so that interpreter directory is absent from the runtime image and the venv's python symlink dangles -- exec fails at container start with "No such file or directory" on /app/.venv/bin/uvicorn. Silent version drift too: uv picked 3.10 despite the 3.12-slim base. UV_PYTHON_PREFERENCE=only-system + UV_PYTHON_DOWNLOADS=never force uv to use /usr/local/bin/python3.12 from the base image, which is present in both stages. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
The host pins Python 3.10 via .python-version for local dev. Keeping the container on the same version avoids subtle behavior differences between developer machines and production (stdlib changes, dep wheel selection, etc.) and means `uv sync` respects the existing pin inside the build context without extra workarounds. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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The previous Dockerfile was a dev setup masquerading as production:
FROM python:latestmeant rebuilds drifted silently over time.uv sync --locked+uv runat CMD meant every container start re-validated the lockfile against the venv, which can touch the package index (at minimum DNS) even when the venv is already built.--reloadis uvicorn's dev mode; it watches the filesystem and respawns workers, each of which re-invokes the CMD and compounds the above.This rewrite:
--locked->--frozenso lockfile drift fails the build loudly instead of being silently reconciled.uv runfrom CMD and invokes uvicorn directly from /app/.venv/bin via PATH. Runtime startup now makes zero PyPI callouts and needs no DNS for package management.--reload.