django-postgres-man-db 0.1.1

Reusable Django management command for PostgreSQL lifecycle, backup, and restore tasks.

django-postgres-man-db

man_db is a small, reusable Django app that provides management commands to manage PostgreSQL databases and backups. It is intended to be dropped into Django projects that use Postgres.

Features

• Management commands (two entry points: man_db and mandb) to perform common Postgres lifecycle tasks:
  • create — create the configured PostgreSQL database
  • drop — terminate connections and drop the database (destructive)
  • reset — delete local app migration files and drop the database (destructive)
  • ping — check that PostgreSQL is reachable
  • backup — create a pg_dump custom-format archive
  • restore — restore a pg_restore archive (destructive)

Requirements

• Python >= 3.11
• Django >= 5.2
• psycopg[binary] and structlog (declared in pyproject.toml)
• pg_dump and pg_restore binaries available on PATH (or provided via env vars)

See pyproject.toml for package metadata and declared dependencies.

Installation

For Django projects that consume a published release, install from PyPI:

uv add django-postgres-man-db
# or
pip install django-postgres-man-db

For local development from this repository, use an editable install:

python -m venv .venv
source .venv/bin/activate
pip install -e .

Then add man_db to your Django INSTALLED_APPS.

# settings.py
INSTALLED_APPS = [
  # ...
  "man_db",
]

Ensure the DATABASES[...] entry you intend to manage uses the Postgres backend (django.db.backends.postgresql). The management commands read connection details from settings.DATABASES.

Environment variables

• PG_DUMP_PATH — optional absolute path to the pg_dump executable. If unset, the command will look for pg_dump on PATH, but only from trusted executable directories.
• PG_RESTORE_PATH — optional absolute path to the pg_restore executable. If unset, the command will look for pg_restore on PATH, but only from trusted executable directories.
• PGPASSWORD — if your DB password is set in DATABASES[...], the package will set PGPASSWORD in the subprocess environment for pg_dump/pg_restore.
• SERVICE_NAME / ENVIRONMENT — optional values used to bind contextvars for structlog (defaults: man_db / local).

Optional Django settings

• MAN_DB_TRUSTED_EXECUTABLE_DIRS — iterable of trusted directories for pg_dump and pg_restore PATH fallback. Defaults to common system binary locations such as /usr/bin, /usr/local/bin, and /usr/lib/postgresql.
• MAN_DB_RESET_APP_ALLOWLIST — iterable of app labels allowed for reset migration deletion when --apps is not passed.

Usage

The package exposes two management command names that are equivalent:

python manage.py man_db <action> [options]
python manage.py mandb <action> [options]

Common examples:

# create the database
python manage.py man_db create

Specifying the database name

The management commands read database connection information from your Django project's settings.DATABASES. The important field for create, backup, and restore actions is the NAME value under the selected database alias.

Example settings.py (using environment variables is recommended for secrets):

import os

DATABASES = {
  "default": {
    "ENGINE": "django.db.backends.postgresql",
    "NAME": os.environ.get("DB_NAME", "my_database_name"),
    "USER": os.environ.get("DB_USER", "app_user"),
    "PASSWORD": os.environ.get("DB_PASSWORD", "secret"),
    "HOST": os.environ.get("DB_HOST", "db.example"),
    "PORT": int(os.environ.get("DB_PORT", 5432)),
  },
  "analytics": {
    "ENGINE": "django.db.backends.postgresql",
    "NAME": "analytics_db",
    "USER": "analytics_user",
    "PASSWORD": "secret",
    "HOST": "db.example",
    "PORT": 5432,
  },
}

How the commands select the database:

• Use the --database option to select a Django database alias (default: default). The command reads the NAME from that alias.
• Example: python manage.py man_db create --database analytics will attempt to create the database named by DATABASES["analytics"]["NAME"].

Important notes:

• The create action requires a non-empty NAME. If DATABASES[alias]["NAME"] is empty, the command raises a CommandError and refuses to proceed.
• For restore, you may use --create-db to tell pg_restore to create the database from the archive; when --create-db is used the command allows an empty NAME because the archive can provide the database name.
• Keep credentials out of source by using os.environ.get(...) or a secrets manager in your settings.py.

More examples:

# check connectivity for a named DB alias
python manage.py man_db ping --database reporting

# create a backup (output dir, optional prefix)
python manage.py man_db backup --output-dir ./backups --prefix nightly

# restore from backup (destructive)
python manage.py man_db restore --backup ./backups/app_20260516_20260516_010203.dump --i-understand

# reset scoped app migrations and drop DB (destructive, must pass --yes)
python manage.py man_db reset --yes --apps my_app another_app

Important flags

• --yes — required to confirm destructive actions (drop, reset).
• --apps — app labels whose migrations may be deleted during reset.
• --database — Django database alias (default: default).
• --output-dir — directory to write backups to (default: <BASE_DIR>/backups).
• --prefix — optional filename prefix for backups (must be a single filename component).
• --compression — compression level for pg_dump custom format (0–9; default: 6).
• --include-owner — include original object owners and privileges in dumps/restores.
• --backup — path to the .dump archive to restore.
• --create-db — when restoring, create the DB from the archive (-C to pg_restore).
• --jobs — number of parallel jobs for pg_restore (default: 2, maximum: local CPU count).
• --i-understand — required to acknowledge destructive restore operations.

Behavior notes

• Backup files are created with a timestamped filename. The implementation ensures generated backup paths cannot escape the requested --output-dir.
• Backup and restore executable paths must be absolute executable files when provided through PG_DUMP_PATH or PG_RESTORE_PATH.
• PATH fallback for pg_dump and pg_restore is restricted to trusted executable directories.
• Restore is destructive by default; the command refuses to run unless --i-understand is provided.
• restore validates --jobs and rejects values outside 1..os.cpu_count().
• reset deletes migration files only for explicitly scoped app labels from --apps or MAN_DB_RESET_APP_ALLOWLIST, and then drops the configured database.

Logging & events

Logging is implemented with structlog. Events are emitted with a log_name (Application, System, Audit) and an event_code (see src/man_db/event_codes.py). The package binds SERVICE_NAME and ENVIRONMENT context variables if present.

If you want to see or persist these structured logs, configure structlog/the stdlib logger in your project as you would normally.

Running tests

The repository includes unit tests that use Django's test framework. To run tests locally:

python -m pip install -e .
python -m pytest -q

Tests rely on DJANGO_SETTINGS_MODULE being set to tests.settings, which the test modules set by default.

Development and contributing

• Fork and open a PR with a clear description of the change.
• Keep changes focused and include tests for new behavior.
• Run the test suite before submitting: python -m pytest.

License

This project is licensed under the MIT License (see pyproject.toml).

Author

Letlaka