docker-seafile-client/IMPROVEMENTS.md

Improvement Plan

This plan prioritizes user safety and a working release pipeline before public portfolio polish. The project already has useful adoption evidence: more than 5,800 Docker Hub pulls, external issues, and external contributions.

Security-sensitive findings should be fixed and released before detailed exploit scenarios are discussed in public issues.

P0 - Release blockers

Restore reproducible image builds

• Replace the unavailable Seafile APT repository used in Dockerfile. Upstream discontinued it; the CLI now ships as an x86_64-only AppImage.
• Install a supported Seafile CLI version from an official source.
• Pin the version and verify its checksum during the build. The checksum is trust-on-first-use: upstream publishes no digest or signature alongside the AppImage, so this is weaker than the signed APT repository it replaces.
• Remove apt-key, which is deprecated and trusts keys globally.
• Add a smoke check that seaf-cli runs to the image build. Note that seaf-cli has no --version flag; use seaf-cli --help and assert the expected subcommands, and record the installed version from the package manager instead.
• Scan the resulting image and review every high or critical finding.
• Establish a stronger trust anchor for the AppImage than a self-derived checksum: an upstream digest or signature, or a verified artifact mirrored somewhere we control.

Acceptance criteria:

• A clean docker build --no-cache . succeeds in CI.
• The installed Seafile version is explicit and current.
• An invalid artifact checksum fails the build. Upstream publishes no signature for the AppImage, so signature verification is not achievable from this source.

Remove shell and path injection risks

• Pass subprocess arguments as arrays instead of joining values into shell command strings in dsc/client.py and dsc/misc.py. The password is no longer wrapped in quotes to survive a shell, which also fixes passwords containing quotes, $, and backticks.
• Replace su -c with a mechanism such as runuser -- that does not need a shell. runuser -u sets the same HOME and a PATH that still finds the seaf-cli wrapper, so the daemon environment is unchanged.
• Treat server-provided library names as untrusted input.
• Resolve every target directory and prove that it remains under /dsc/seafile before creating or writing it. Symlinks are resolved first, so an existing symlink in the libraries directory cannot redirect a write.
• Define how duplicate, absolute, empty, and traversal-style library names are handled. See dsc/paths.py and the "Some notes" section of the README.

Acceptance criteria:

• Tests cover quotes, command substitutions, separators, newlines, absolute paths, parent traversal, Unicode, and colliding library names.
• No configuration or server value can execute a command or escape the data directory.

Support secrets safely

• Implement PASSWORD_FILE for Docker Compose and Swarm secrets. Only a trailing newline is stripped, so a secret keeps any surrounding spaces.
• Add token-based authentication and TOKEN_FILE if supported by the installed Seafile CLI. It is: seaf-cli sync takes -T, and ignores the password when a token is given.
• Define precedence and reject conflicting secret sources. Two sources for one secret (PASSWORD with PASSWORD_FILE) are rejected; a token takes precedence over a password, as it does in seaf-cli itself.
• Ensure secrets are absent from application logs. Both the password and the token are masked before a command is logged.
• Document any upstream limitation that exposes a secret in process arguments. seaf-cli accepts credentials only as arguments, so a secret is visible to any process in the container. The account password no longer goes there: the client authenticates with an API token, which can be revoked. See the README.

Acceptance criteria:

• A container can authenticate with a mounted file under /run/secrets.
• Tests reject conflicting inputs and verify newline handling.
• Logs never contain the password or token.

Correct environment parsing and defaults

• Replace direct os.getenv() assignments in start.py with typed parsers. See dsc/config.py and defaults_from_env().
• Preserve the documented defaults for upload limit, download limit, and delete-confirm threshold when variables are absent. They were not: an unset variable overwrote the argparse default with None, so a default container sent the literal string None for all three.
• Validate UID, GID, limits, threshold, and booleans before daemon startup. UID and GID are now integers; as strings they never equalled the integers they were compared against, so usermod ran on every start.
• Reject negative and malformed numeric values with useful messages.
• Do not pass None as a Seafile configuration value. Booleans are also rendered as true/false rather than Python's True/False. This fixed DISABLE_VERIFY_CERTIFICATE, which never worked. The daemon reads the key with seafile_session_config_get_bool, which is g_strcmp0(value, "true") == 0, so it accepts only the exact string "true". Python's str(True) stored the string "True", which did not match and was therefore read as false, leaving verification on for anyone who asked to disable it. The default stored the string "False", which is also not "true" and so was correctly read as false.

Acceptance criteria:

• Table-driven tests cover unset, zero, valid, negative, and malformed values.
• A default container receives exactly the defaults documented in the README.

Make startup and shutdown deterministic

• Check every important subprocess return code. A failed seaf-cli sync is reported per library and does not stop the remaining ones.
• Add timeouts to daemon startup, shutdown, and readiness polling. See DAEMON_START_TIMEOUT and DAEMON_STOP_TIMEOUT in dsc/const.py; the stop timeout is deliberately below the 10 second docker stop grace period.
• Handle SIGTERM and SIGINT and stop the daemon in finally.
• Return a nonzero container exit code on configuration or daemon failure.
• Produce actionable errors instead of waiting forever.

Acceptance criteria:

• A daemon that never becomes ready causes a bounded failure.
• docker stop performs a graceful shutdown within Docker's timeout.
• Failure-injection tests cover command errors and interrupted startup.

Add real tests

• Add unit tests for configuration parsing, command construction, library resolution, path validation, retries, and status parsing. Command construction and path validation are covered in tests/; configuration parsing, retries, and status parsing are not.
• Add regression tests for externally reported password and deletion threshold issues.
• Add a container smoke test for imports, installed CLI version, startup, and shutdown using controlled fakes. See tests/smoke.sh, run by the image build job. It exercises the real seaf-cli and seaf-daemon, which the unit tests cannot: the runner is x86_64, matching the AppImage. The pinned client version is exposed as SEAFILE_CLI_VERSION in the image so it can be asserted at runtime.
• Keep image construction as a separate CI job so packaging failures are distinguishable from application failures. The unit-test job does not depend on the image build.

Acceptance criteria:

• CI fails on a deliberate parsing, quoting, or path-safety regression.
• Application tests run without requiring a live production server.

Repair and validate the quick start

• Change the Compose example to mapping syntax so quote characters are not passed as part of LIBRARY_ID.
• Pin the example to a versioned image instead of an implicit latest tag.
• Add a checked-in compose.example.yaml.
• Validate it with docker compose config in CI.

P1 - Reliability and supply chain

Networking and protocol behavior

• Add explicit connect and read timeouts to all HTTP requests.
• Define a bounded retry budget with backoff and jitter. Measured: the current Retry(total=30, backoff_factor=2, backoff_max=60) with no request timeout waits about 26 minutes on a single unreachable server before giving up, which is indistinguishable from a hang. Observed while writing the smoke test, when a probe pointed at an unroutable host.
• Handle authentication, rate limits, malformed responses, and retryable server errors separately.
• Make TLS configuration consistent between Python requests and Seafile.
• Support a custom CA bundle; keep certificate disabling as a last resort.
• Prefer structured JSON output from seaf-cli over parsing display text. seaf-cli list --json is used instead of splitting the display columns, which could not represent a library name or a path containing whitespace. list-remote still uses the HTTP API rather than the CLI.
• Reject ambiguous library names and an empty requested library set.

Runtime hardening

• Run the long-lived process as the configured non-root user after setup.
• Reject UID or GID zero unless a documented use case requires it.
• Add a health check for the daemon and RPC endpoint.
• Handle temporary RPC failures and daemon restarts without corrupting state.
• Document supported CPU architectures instead of implying multi-platform support.

CI and release pipeline

• Replace actions/checkout@v2 and docker/build-push-action@v1.
• Set workflow permissions explicitly to contents: read by default.
• Use a scoped Docker Hub access token. The workflow now reads secrets.DOCKER_TOKEN; the repository secret still has to be created from a scoped Docker Hub token before the next tag is pushed.
• Build a release image once and attach all version and latest tags to the same manifest digest.
• Add OCI labels via docker/metadata-action.
• Add an SBOM, provenance, and image signing.
• Add dependency updates for Python, Docker, and GitHub Actions. A weekly Dependabot configuration covers requirements.txt, the Dockerfile base image, and the workflow actions. The Seafile AppImage is fetched by URL and checksum, so it still has to be bumped by hand.
• Run dependency and image scans on pull requests and on a schedule.

Acceptance criteria:

• Every tag for one release resolves to the same manifest digest.
• Pull requests cannot access publication credentials.
• The current dependency update pull request passes all checks.

P2 - Maintainability and presentation

Simplify the implementation

• Separate configuration, subprocess execution, library resolution, and status monitoring so each can be tested independently.
• Remove unused imports and unnecessary dependencies. Both pinned requirements are used; urllib3 is imported directly but only pinned transitively through requests.
• Add type annotations and static checks at external-input boundaries.
• Make logging configurable and avoid forced dependency debug logs.
• Add .dockerignore and reduce unnecessary image packages. .dockerignore is in place; binutils and squashfs-tools are still shipped in the final image because the AppImage is unpacked in the same stage.

Establish a visible maintenance process

• Publish GitHub Releases for future tags with compatibility and rollback notes.
• Add CHANGELOG.md, SECURITY.md, and concise contribution guidance.
• Add issue templates that request image, client, and server versions plus sanitized logs.
• Triage stale issues and document the status of Docker secret support.
• Enable branch protection and require passing CI before merge.

Improve the public project page

• Link directly to the Docker Hub image near the top of README.md.
• Add CI, release, Docker pulls, and license badges after the checks are trustworthy.
• Add a short architecture and process-lifecycle section.
• Add a tested compatibility matrix.
• Explain deletion behavior, volume ownership, state loss, backup expectations, and recovery.
• Fix example inconsistencies and typographical errors.

Release gate

Do not publish the next image until all of the following are true:

• A clean, reproducible build uses a supported Seafile client.
• External values cannot reach a shell or escape the data directory.
• Secret-file or token authentication is covered by tests.
• Startup, retries, and shutdown are bounded and observable.
• Unit and container smoke tests pass.
• The steady-state process is non-root and has a useful health check.
• Release tags point to one scanned and signed image digest.
• The README quick start succeeds from a clean environment.