1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
|
======================================
How to provide initial data for models
======================================
It's sometimes useful to pre-populate your database with hard-coded data when
you're first setting up an app. You can provide initial data with migrations or
fixtures.
Providing initial data with migrations
======================================
If you want to automatically load initial data for an app, create a
:ref:`data migration <data-migrations>`. Migrations are run when setting up the
test database, so the data will be available there, subject to :ref:`some
limitations <test-case-serialized-rollback>`.
.. _initial-data-via-fixtures:
Providing data with fixtures
============================
You can also provide data using fixtures, however, this data isn't loaded
automatically, except if you use :attr:`.TransactionTestCase.fixtures`.
A fixture is a collection of data that Django knows how to import into a
database. The most straightforward way of creating a fixture if you've already
got some data is to use the :djadmin:`manage.py dumpdata <dumpdata>` command.
Or, you can write fixtures by hand; fixtures can be written as JSON, XML or YAML
(with PyYAML_ installed) documents. The :doc:`serialization documentation
</topics/serialization>` has more details about each of these supported
:ref:`serialization formats <serialization-formats>`.
.. _PyYAML: https://pyyaml.org/
As an example, though, here's what a fixture for a ``Person`` model might look
like in JSON:
.. code-block:: js
[
{
"model": "myapp.person",
"pk": 1,
"fields": {
"first_name": "John",
"last_name": "Lennon"
}
},
{
"model": "myapp.person",
"pk": 2,
"fields": {
"first_name": "Paul",
"last_name": "McCartney"
}
}
]
And here's that same fixture as YAML:
.. code-block:: yaml
- model: myapp.person
pk: 1
fields:
first_name: John
last_name: Lennon
- model: myapp.person
pk: 2
fields:
first_name: Paul
last_name: McCartney
You'll store this data in a ``fixtures`` directory inside your app.
You can load data by calling :djadmin:`manage.py loaddata <loaddata>`
``<fixturename>``, where ``<fixturename>`` is the name of the fixture file
you've created. Each time you run :djadmin:`loaddata`, the data will be read
from the fixture and re-loaded into the database. Note this means that if you
change one of the rows created by a fixture and then run :djadmin:`loaddata`
again, you'll wipe out any changes you've made.
Where Django finds fixture files
--------------------------------
By default, Django looks in the ``fixtures`` directory inside each app for
fixtures. You can set the :setting:`FIXTURE_DIRS` setting to a list of
additional directories where Django should look.
When running :djadmin:`manage.py loaddata <loaddata>`, you can also
specify a path to a fixture file, which overrides searching the usual
directories.
.. seealso::
Fixtures are also used by the :ref:`testing framework
<topics-testing-fixtures>` to help set up a consistent test environment.
|
