Commands
========

InstrumentDB implements a number of commands that can be executed from
the terminal. These are meant to ease the management of the database.

Here is the list:

- :ref:`export_cmd`
- :ref:`import_cmd`
- :ref:`updatedb_cmd`
- :ref:`deletedatafiles_cmd`
- :ref:`delete_all`

These commands can be executed from the command line using the syntax

.. code-block::

   python3 manage.py CMD

where ``CMD`` is the name of the command, e.g., ``export``. To get
help for the command, run

.. code-block::

   python3 manage.py CMD --help


.. _export_cmd:
``export``
----------

This command exports the content of the database into a folder.
The index of the database, all the metadata, the release information
and so on are stored in a file named ``schema.json``, while all the
data files, format specifications, plots, etc., are saved in separate
directories.

The purpose of the ``export`` command is to be paired with ``import``:
it enables a database to be created on a machine and replicated into
another.


.. _import_cmd:
``import``
----------

This command imports a JSON file and the associated files that have
been produced by the :ref:`_export_cmd` command.


.. _updatedb_cmd:
``updatedb``
------------

The database keeps a copy of every release in the form of a JSON file.
This command rebuilds all these JSON files. It should be triggered
if you fear that these files got corrupted.


.. _deletedatafiles_cmd:
``delete-data-files``
---------------------

Delete a set of data files from the database. You can specify a release tag
using the ``--release`` command-line switch: in this case, all the data files
belonging to the data release will be deleted. Any data file belonging to more
than one data release will be left untouched, in order not to leave
dangling references.

.. _deleteall_cmd:
``delete-all``
--------------

This command deletes all the entities, quantities, data files, and
format specifications from the database.