eea.flis.metadata 0.5.4

EEA Metadata models replication support

====================
Flis Metadata Client
====================

Client for Flis application that require common metadata

Quick start
-----------

1. Add "flis_metadata.common" and "flis_metadata.client"
to your INSTALLED_APPS setting like this::

INSTALLED_APPS = (
...
'flis_metadata.common',
'flis_metadata.client',
)

2. Add METADATA_REMOTE_HOST into your settings file::

METADATA_REMOTE_HOST = 'http://localhost:8000'
METADATA_REMOTE_PATH = ''

3. Run `python manage.py syncdb` to create the metadata models.

4. Run `python manage.py migrate` to migrate the common app.
Note:
If you are using django below 1.7.0 run `pip install south` and add it to
INSTALLED_APPS.

5. Run `python manage.py sync_remote_models` to sync the metadata models with
the remote ones.

How to add a new model
----------------------
We want to move model :code:`Foo` from :code:`flis.someapp` to be
replicated in all flis apps

In the this app:
1. Add the model in :code:`common/models.py`. Make sure it extends
:code:`ReplicatedModel`.

2. Add urls views and templates to edit it.

3. Add a fixture having all instances of :code:`Foo` for every flis app.
Note:
This data will be replicated and migrated in every app that uses
this package, so make sure that the migration includes everything

4. Update the pip package using :code:`setup.py`.

In :code:`flis.someapp` and other apps using this model
1. Update :code:`eaa.flis.metadata` package in requirements.txt and
install it.

2. For every relation to the foo model::

# add a new fake foreign key field
x = models.ForeingKey(Foo)
fake_x = models.ForeingKey('common.Foo')

# or add a new fake many to many field
y = models.ManyToManyField(Foo)
fake_y = models.ManyToManyField('common.Foo')

3. Add a migration to add the new fields

4. Create a datamigration that

1. Calls :code:`load_metadata_fixtures` management command

2. For every :code:`x` copies the same information in
:code:`fake_x` using the instance found in :code:`common.Foo`::

obj.fake_x = orm['common.Foo'].objects.get(title=obj.x.title)

# or

for y in obj.y.all():
obj.fake_y.add(orm['common.Foo'].objects.get(title=y.title)

5. Remove the :code:`Foo` model and :code:`x` fields from
:code:`flis.someapp`

6. Create an automatic schemamigration to reflect the removals

7. Rename `fake_x` fields to `x` in `models.py`

8. In the migration generated at 5. rename the fields and M2M tables from
`fake_x` to `x`

9. Run the migration in different corner cases.
Note:
You can browse through flis.flip, flis.horizon-scanning-tool or
flis.live_catalogue to see an example of such migrations.