SQLAlchemy data layer for Eve-powered RESTful APIs
… image:: https://travis-ci.org/pyeve/eve-sqlalchemy.svg?branch=master
:target: https://travis-ci.org/pyeve/eve-sqlalchemy
Powered by Eve, SQLAlchemy and good intentions this extension allows
to effortlessly build and deploy highly customizable, fully featured
RESTful Web Services with SQL-based backends.
As of some years ago, Eve-SQLAlchemy has been effectively unmaintained. I am no
longer actively using it, which makes it increasingly difficult to find the
time for even small updates. If anyone is interested in taking over maintenance
of Eve-SQLAlchemy, please reach out to me.
The following code blocks are excerpts of examples/one_to_many
and should
give you an idea of how Eve-SQLAlchemy is used. A complete working example can
be found there. If you are not familiar with Eve <https://python-eve.org/>
_
and SQLAlchemy <https://www.sqlalchemy.org/>
_, it is recommended to read up
on them first.
For this example, we declare two SQLAlchemy mappings (from domain.py
):
… code-block:: python
class Parent(BaseModel):
__tablename__ = 'parent'
id = Column(Integer, primary_key=True)
children = relationship("Child")
class Child(BaseModel):
__tablename__ = 'child'
id = Column(Integer, primary_key=True)
parent_id = Column(Integer, ForeignKey('parent.id'))
As for Eve, a settings.py
is used to configure our API. Eve-SQLAlchemy,
having access to a lot of metadata from your models, can automatically generate
a great deal of the DOMAIN
dictionary for you:
… code-block:: python
DEBUG = True
SQLALCHEMY_DATABASE_URI = 'sqlite://'
SQLALCHEMY_TRACK_MODIFICATIONS = False
RESOURCE_METHODS = ['GET', 'POST']
DOMAIN = DomainConfig({
'parents': ResourceConfig(Parent),
'children': ResourceConfig(Child)
}).render()
Finally, running our application server is easy (from app.py
):
… code-block:: python
app = Eve(validator=ValidatorSQL, data=SQL)
db = app.data.driver
Base.metadata.bind = db.engine
db.Model = Base
# create database schema on startup and populate some example data
db.create_all()
db.session.add_all([Parent(children=[Child() for k in range(n)])
for n in range(10)])
db.session.commit()
# using reloader will destroy the in-memory sqlite db
app.run(debug=True, use_reloader=False)
The API is now live, ready to be consumed:
… code-block:: console
$ curl -s http://localhost:5000/parents | python -m json.tool
… code-block:: json
{
"_items": [
{
"_created": "Sun, 22 Oct 2017 07:58:28 GMT",
"_etag": "f56d7cb013bf3d8449e11e8e1f0213f5efd0f07d",
"_links": {
"self": {
"href": "parents/1",
"title": "Parent"
}
},
"_updated": "Sun, 22 Oct 2017 07:58:28 GMT",
"children": [],
"id": 1
},
{
"_created": "Sun, 22 Oct 2017 07:58:28 GMT",
"_etag": "dd1698161cb6beef04f564b2e18804d4a7c4330d",
"_links": {
"self": {
"href": "parents/2",
"title": "Parent"
}
},
"_updated": "Sun, 22 Oct 2017 07:58:28 GMT",
"children": [
1
],
"id": 2
},
"..."
],
"_links": {
"parent": {
"href": "/",
"title": "home"
},
"self": {
"href": "parents",
"title": "parents"
}
},
"_meta": {
"max_results": 25,
"page": 1,
"total": 10
}
}
All you need to bring your API online is a database, a configuration
file (defaults to settings.py
) and a launch script. Overall, you
will find that configuring and fine-tuning your API is a very simple
process.
Eve-SQLAlchemy is thoroughly tested under Python 2.7-3.7 and PyPy.
The offical project documentation can be accessed at
eve-sqlalchemy.readthedocs.org <https://eve-sqlalchemy.readthedocs.org/>
_. For full working examples,
especially regarding different relationship types, see the examples
directory in this repository.