Allow to query a django RestAPI with same interface as the django ORM. (the targeted API must use django-rest-framework + dynamic-rest libraries) In fact, it works like any other database engine. You add the rest_models engine in an alternate database and the rest_models databe router. Then add APIMeta class to the models querying the API, voilà !
Stable branch
Development status
Install using pip:
pip install django-rest-models
Alternatively, you can download or clone this repo and install with :
pip install -e .
.
This database wrapper work with
- python 2.7, 3.4, 3.5
- django 1.8 , 1.9, 1.10
On the api, this is tested against
- django-rest-framework 3.4, 3.5
- dynamic-rest 1.5, 1.6
settings.py:
DATABASES = {
'default': {
...
},
'api': {
'ENGINE': 'rest_models.backend',
'NAME': 'https://requestb.in/',
'USER': 'userapi',
'PASSWORD': 'passwordapi',
'AUTH': 'rest_models.backend.auth.BasicAuth',
},
}
DATABASE_ROUTERS = [
'rest_models.router.RestModelRouter',
]
models.py:
class MyModel(models.Model):
field = models.IntegerField()
...
class Meta:
# basic django meta Stuff
verbose_name = 'my model'
# the only customisation that make this model special
class APIMeta:
pass
class MyOtherModel(models.Model):
other_field = models.IntegerField()
first_model = models.ForeignKey(MyModel, db_column='mymodel')
...
class Meta:
# basic django meta Stuff
verbose_name = 'my other model'
# the only customisation that make this model special
class APIMeta:
pass
To allow this database adapter to work like a relational one, the targeted API must respect some requirements :
- dynamic-rest installed and all serializers/views must respectively inherit from Dynamic* (DynamicModelSerializer, etc...)
Each API serializer must :
- Provide the id field
- Provide the related field (ManyToMany and ForeignKey on Models) as DynamicRelationField
- Provide the reverse related field. We must, for each ForeignKey and ManyToMany, add a field on the related model's serializer.
class MenuSerializer(DynamicModelSerializer):
pizzas = DynamicRelationField('PizzaSerializer', many=True) # Menu.pizza = ManyToMany
class Meta:
model = Menu
name = 'menu'
fields = ('id', 'code', 'name', 'pizzas')
deferred_fields = ('pizza_set', )
class PizzaSerializer(DynamicModelSerializer):
toppings = DynamicRelationField(ToppingSerializer, many=True)
menu = DynamicRelationField(MenuSerializer) # Add this because Menu.pizza = ManyToMany
class Meta:
model = Pizza
name = 'pizza'
fields = ('id', 'name', 'price', 'from_date', 'to_date', 'toppings', 'menu')
django-rest-models provide a way to check the consistency of the api with the local models via the django check framework. At each startup, it will query the api with OPTIONS to check if the local models match the remote serializers.
Since this is not a real relational database, all feature cannot be implemented. Some limitations are inherited by dynamic-rest filtering system too.
Aggregations : is not implemented on the api endpoint, maybe in future releases
Complex filtering using OR : all filter passed to dynamic-rest is ANDed together, so no OR is possible
Negated AND in filtering: a negated AND give a OR, so previous limitation apply
Negated OR in filtering: since the compitation of nested filter is complexe and error prone, we disable all OR. in fact, only some nested of AND is accepted. only the final value of the Q() object can be negated
for short, you CANNOT :
Pizza.objects.aggregate()
Pizza.objects.annotate()
Pizza.objects.filter(Q(..) | Q(..))
Pizza.objects.exclude(Q(..) & Q(..))
Pizza.objects.exclude(Q(..) | Q(..))
but you can :
Pizza.objects.create
Pizza.objects.bulk_create
Pizza.objects.update
Pizza.objects.bulk_update
Pizza.objects.select_related
Pizza.objects.prefetch_related
Pizza.objects.values
Pizza.objects.values_list
Pizza.objects.delete
Pizza.objects.count()
Pizza.objects.filter(..., ..., ...)
Pizza.objects.filter(...).filter(...).exclude(...)
Pizza.objects.exclude(..., ...).exclude(...)
Pizza.objects.filter(Q(..) & Q(..))
Note
prefetch_related work as expected, but the performance is readly bad. As a matter of fact, a Pizza.objects.prefetch_related('toppings')
will query the toppings for all pizzas as expected, but the query to recover the pizza will contains the linked pizza in the response.
If the database contains a great number of pizzas for the given toppings, the response will contains them all, even if it's
useless at first glance, the linked pizza for each topping is mandotary to django to glue topping <=> pizza relationships.
So, be careful when using prefetch_related.
Some specific behaviour has been implemented to use the extra feature of a Rest API :
- When inserting, the resulting model is returned by the API. the inserted model is updated with the resulting values.
This imply 2 things:
- If you provided default values for fields in the api, these data will be populated into your created instance if it was ommited.
- If the serializer have some computed data, its data will always be used as a replacement of the one you gave to your models. (cf example: Pizza.cost which is the sum of the cost of the toppling. after each save, its value will be updated)
This database api support :
- select_related
- order_by
- only
- defer
- filter
- exclude
- delete
- update
- create
- bulk create (with retrive of pk)
- ManyToManyField
- ForeignKey*
Note
ForeignKey must have db_column fixed to the name of the reflected field in the api. or all update/create won't use the value if this field
The full documentation is at http://django-rest-models.readthedocs.org/en/latest/.
- Python 2.7, 3.4, 3.5
- Django >= 1.8
Contributions and pull requests are welcome.
If you found a bug or if you have a request for additional feature, please use the issue tracker on GitHub.
https://github.com/Yupeek/django-rest-models/issues
You can use this under GPLv3.
Original author: Darius BERNARD.
Thanks to django for this amazing framework.
django-rest-models's People
Recommend Projects
-
React
A declarative, efficient, and flexible JavaScript library for building user interfaces.
-
Vue.js
🖖 Vue.js is a progressive, incrementally-adoptable JavaScript framework for building UI on the web.
-
Typescript
TypeScript is a superset of JavaScript that compiles to clean JavaScript output.
-
TensorFlow
An Open Source Machine Learning Framework for Everyone
-
Django
The Web framework for perfectionists with deadlines.
-
Laravel
A PHP framework for web artisans
-
D3
Bring data to life with SVG, Canvas and HTML. 📊📈🎉
-
Recommend Topics
-
javascript
JavaScript (JS) is a lightweight interpreted programming language with first-class functions.
-
web
Some thing interesting about web. New door for the world.
-
server
A server is a program made to process requests and deliver data to clients.
-
Machine learning
Machine learning is a way of modeling and interpreting data that allows a piece of software to respond intelligently.
-
Visualization
Some thing interesting about visualization, use data art
-
Game
Some thing interesting about game, make everyone happy.
Recommend Org
-
Facebook
We are working to build community through open source technology. NB: members must have two-factor auth.
-
Microsoft
Open source projects and samples from Microsoft.
-
Google
Google ❤️ Open Source for everyone.
-
Alibaba
Alibaba Open Source for everyone
-
D3
Data-Driven Documents codes.
-
Tencent
China tencent open source team.