dj-database-url

DJ-Database-URL

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   :target: https://codecov.io/gh/jazzband/dj-database-url

This simple Django utility allows you to utilize the
`12factor <http://www.12factor.net/backing-services>`_ inspired
``DATABASE_URL`` environment variable to configure your Django application.

The ``dj_database_url.config`` method returns a Django database connection
dictionary, populated with all the data specified in your URL. There is
also a `conn_max_age` argument to easily enable Django's connection pool.

If you'd rather not use an environment variable, you can pass a URL in directly
instead to ``dj_database_url.parse``.

Installation
------------

Installation is simple:

.. code-block:: console

    $ pip install dj-database-url

Usage
-----

1. If ``DATABASES`` is already defined:

- Configure your database in ``settings.py`` from ``DATABASE_URL``:

  .. code-block:: python

      import dj_database_url

      DATABASES['default'] = dj_database_url.config(
          conn_max_age=600,
          conn_health_checks=True,
      )

- Provide a default:

  .. code-block:: python

      DATABASES['default'] = dj_database_url.config(
          default='postgres://...',
          conn_max_age=600,
          conn_health_checks=True,
      )

- Parse an arbitrary Database URL:

  .. code-block:: python

      DATABASES['default'] = dj_database_url.parse(
          'postgres://...',
          conn_max_age=600,
          conn_health_checks=True,
      )

2. If ``DATABASES`` is not defined:

- Configure your database in ``settings.py`` from ``DATABASE_URL``:

  .. code-block:: python

      import dj_database_url

      DATABASES = {
          'default': dj_database_url.config(
              conn_max_age=600,
              conn_health_checks=True,
          ),
      }

- You can provide a default, used if the ``DATABASE_URL`` setting is not defined:

  .. code-block:: python

      DATABASES = {
          'default': dj_database_url.config(
              default='postgres://...',
              conn_max_age=600,
              conn_health_checks=True,
          )
      }

- Parse an arbitrary Database URL:

  .. code-block:: python

      DATABASES = {
          'default': dj_database_url.parse(
              'postgres://...',
              conn_max_age=600,
              conn_health_checks=True,
          )
      }

``conn_max_age`` sets the |CONN_MAX_AGE setting|__, which tells Django to
persist database connections between requests, up to the given lifetime in
seconds. If you do not provide a value, it will follow Django’s default of
``0``. Setting it is recommended for performance.

.. |CONN_MAX_AGE setting| replace:: ``CONN_MAX_AGE`` setting
__ https://docs.djangoproject.com/en/stable/ref/settings/#conn-max-age

``conn_health_checks`` sets the |CONN_HEALTH_CHECKS setting|__ (new in Django
4.1), which tells Django to check a persisted connection still works at the
start of each request. If you do not provide a value, it will follow Django’s
default of ``False``. Enabling it is recommended if you set a non-zero
``conn_max_age``.

.. |CONN_HEALTH_CHECKS setting| replace:: ``CONN_HEALTH_CHECKS`` setting
__ https://docs.djangoproject.com/en/stable/ref/settings/#conn-health-checks

Strings passed to `dj_database_url` must be valid URLs; in
particular, special characters must be url-encoded. The following url will raise
a `ValueError`:

.. code-block:: plaintext

    postgres://user:p#ssword!@localhost/foobar

and should instead be passed as:

.. code-block:: plaintext

    postgres://user:p%23ssword!@localhost/foobar

`TEST <https://docs.djangoproject.com/en/stable/ref/settings/#test>`_ settings can be configured using the ``test_options`` attribute::

    DATABASES['default'] = dj_database_url.config(default='postgres://...', test_options={'NAME': 'mytestdatabase'})


Supported Databases
-------------------

Support currently exists for PostgreSQL, PostGIS, MySQL, MySQL (GIS),
Oracle, Oracle (GIS), Redshift, CockroachDB, Timescale, Timescale (GIS) and SQLite.

If you want to use
some non-default backends, you need to register them first:

.. code-block:: python

    import dj_database_url

    # registration should be performed only once
    dj_database_url.register("mysql-connector", "mysql.connector.django")

    assert dj_database_url.parse("mysql-connector://user:password@host:port/db-name") == {
        "ENGINE": "mysql.connector.django",
        # ...other connection params
    }

Some backends need further config adjustments (e.g. oracle and mssql
expect ``PORT`` to be a string). For such cases you can provide a
post-processing function to ``register()`` (note that ``register()`` is
used as a **decorator(!)** in this case):

.. code-block:: python

    import dj_database_url

    @dj_database_url.register("mssql", "sql_server.pyodbc")
    def stringify_port(config):
        config["PORT"] = str(config["PORT"])

    @dj_database_url.register("redshift", "django_redshift_backend")
    def apply_current_schema(config):
        options = config["OPTIONS"]
        schema = options.pop("currentSchema", None)
        if schema:
            options["options"] = f"-c search_path={schema}"

    @dj_database_url.register("snowflake", "django_snowflake")
    def adjust_snowflake_config(config):
        config.pop("PORT", None)
        config["ACCOUNT"] = config.pop("HOST")
        name, _, schema = config["NAME"].partition("/")
        if schema:
            config["SCHEMA"] = schema
            config["NAME"] = name
        options = config.get("OPTIONS", {})
        warehouse = options.pop("warehouse", None)
        if warehouse:
            config["WAREHOUSE"] = warehouse
        role = options.pop("role", None)
        if role:
            config["ROLE"] = role

URL schema
----------

+----------------------+-----------------------------------------------+--------------------------------------------------+
| Engine               | Django Backend                                | URL                                              |
+======================+===============================================+==================================================+
| PostgreSQL           | ``django.db.backends.postgresql`` [1]_        | ``postgres://USER:PASSWORD@HOST:PORT/NAME`` [2]_ |
|                      |                                               | ``postgresql://USER:PASSWORD@HOST:PORT/NAME``    |
+----------------------+-----------------------------------------------+--------------------------------------------------+
| PostGIS              | ``django.contrib.gis.db.backends.postgis``    | ``postgis://USER:PASSWORD@HOST:PORT/NAME``       |
+----------------------+-----------------------------------------------+--------------------------------------------------+
| MSSQL                | ``sql_server.pyodbc``                         | ``mssql://USER:PASSWORD@HOST:PORT/NAME``         |
+----------------------+-----------------------------------------------+--------------------------------------------------+
| MSSQL [5]_           | ``mssql``                                     | ``mssqlms://USER:PASSWORD@HOST:PORT/NAME``       |
+----------------------+-----------------------------------------------+--------------------------------------------------+
| MySQL                | ``django.db.backends.mysql``                  | ``mysql://USER:PASSWORD@HOST:PORT/NAME`` [2]_    |
+----------------------+-----------------------------------------------+--------------------------------------------------+
| MySQL (GIS)          | ``django.contrib.gis.db.backends.mysql``      | ``mysqlgis://USER:PASSWORD@HOST:PORT/NAME``      |
+----------------------+-----------------------------------------------+--------------------------------------------------+
| SQLite               | ``django.db.backends.sqlite3``                | ``sqlite:///PATH`` [3]_                          |
+----------------------+-----------------------------------------------+--------------------------------------------------+
| SpatiaLite           | ``django.contrib.gis.db.backends.spatialite`` | ``spatialite:///PATH`` [3]_                      |
+----------------------+-----------------------------------------------+--------------------------------------------------+
| Oracle               | ``django.db.backends.oracle``                 | ``oracle://USER:PASSWORD@HOST:PORT/NAME`` [4]_   |
+----------------------+-----------------------------------------------+--------------------------------------------------+
| Oracle (GIS)         | ``django.contrib.gis.db.backends.oracle``     | ``oraclegis://USER:PASSWORD@HOST:PORT/NAME``     |
+----------------------+-----------------------------------------------+--------------------------------------------------+
| Redshift             | ``django_redshift_backend``                   | ``redshift://USER:PASSWORD@HOST:PORT/NAME``      |
+----------------------+-----------------------------------------------+--------------------------------------------------+
| CockroachDB          | ``django_cockroachdb``                        | ``cockroach://USER:PASSWORD@HOST:PORT/NAME``     |
+----------------------+-----------------------------------------------+--------------------------------------------------+
| Timescale [6]_       | ``timescale.db.backends.postgresql``          | ``timescale://USER:PASSWORD@HOST:PORT/NAME``     |
+----------------------+-----------------------------------------------+--------------------------------------------------+
| Timescale (GIS) [6]_ | ``timescale.db.backend.postgis``              | ``timescalegis://USER:PASSWORD@HOST:PORT/NAME``  |
+----------------------+-----------------------------------------------+--------------------------------------------------+

.. [1] The django.db.backends.postgresql backend is named django.db.backends.postgresql_psycopg2 in older releases. For
       backwards compatibility, the old name still works in newer versions. (The new name does not work in older versions).
.. [2] With PostgreSQL or CloudSQL, you can also use unix domain socket paths with
       `percent encoding <http://www.postgresql.org/docs/9.2/interactive/libpq-connect.html#AEN38162>`_:
       ``postgres://%2Fvar%2Flib%2Fpostgresql/dbname``
       ``mysql://uf07k1i6d8ia0v@%2fcloudsql%2fproject%3alocation%3ainstance/dbname``
.. [3] SQLite connects to file based databases. The same URL format is used, omitting
       the hostname, and using the "file" portion as the filename of the database.
       This has the effect of four slashes being present for an absolute file path:
       ``sqlite:////full/path/to/your/database/file.sqlite``.
.. [4] Note that when connecting to Oracle the URL isn't in the form you may know
       from using other Oracle tools (like SQLPlus) i.e. user and password are separated
       by ``:`` not by ``/``. Also you can omit ``HOST`` and ``PORT``
       and provide a full DSN string or TNS name in ``NAME`` part.
.. [5] Microsoft official `mssql-django <https://github.com/microsoft/mssql-django>`_ adapter.
.. [6] Using the django-timescaledb Package which must be installed.


Contributing
------------

We welcome contributions to this project. Projects can take two forms:

1. Raising issues or helping others through the github issue tracker.
2. Contributing code.

Raising Issues or helping others:
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

When submitting an issue or helping other remember you are talking to humans who have feelings, jobs and lives of their
own. Be nice, be kind, be polite. Remember english may not be someone first language, if you do not understand or
something is not clear be polite and re-ask/ re-word.

Contributing code:
^^^^^^^^^^^^^^^^^^

* Before writing code be sure to check existing PR's and issues in the tracker.
* Write code to the pylint spec.
* Large or wide sweeping changes will take longer, and may face more scrutiny than smaller confined changes.
* Code should be pass `black` and `flake8` validation.