Add sqlalchemy_example.py for sqlalchemy integration example

examples/sqlalchemy_example.py

@@ -0,0 +1,89 @@
+""" SQLAlchemy integration demo
+Use sqlalchemy to connect a in-memory sqlite database
+Defined a table User contains id, name, fullname, password as its columns
+Provider RESTFul service
+GET /users to get all of users in User table
+POST /user to create user
+GET /users/{id} to get user with specific id
+
+Could test it with after running the sanic server:
+curl http://localhost:8000/users
+curl http://localhost:8000/users/1
+curl http://localhost:8000/users/4
+curl http://localhost:8000/user --data '{"name": "ed", "password":"f8s7ccs","fullname":"Ed Jones"}'
+"""
+
+from sanic import Sanic
+from sanic.response import json
+from sanic.exceptions import NotFound
+from sqlalchemy import (
+    Column, String, Integer, Sequence,
+    create_engine
+)
+from sqlalchemy.orm import sessionmaker
+from sqlalchemy.ext.declarative import declarative_base
+
+
+Base = declarative_base()
+
+
+class User(Base):
+    __tablename__ = "users"
+    id = Column(Integer, Sequence("user_id_seq"), primary_key=True)
+    name = Column(String(50))
+    fullname = Column(String(50))
+    password = Column(String(12))
+
+    def serialize(self):
+        return {
+            "id": self.id,
+            "name": self.name,
+            "fullname": self.fullname,
+            "password": self.password,
+        }
+
+engine = create_engine("sqlite://")
+Base.metadata.create_all(engine)
+
+session = sessionmaker()
+session.configure(bind=engine)
+
+s = session()
+s.add_all([
+    User(name="wendy", fullname="Wendy Williams", password="foobar"),
+    User(name="mary", fullname="Mary Contrary", password="xxg527"),
+    User(name="fred", fullname="Fred Flinstone", password="blah")])
+s.commit()
+
+app = Sanic(__name__)
+
+
+@app.route("/users", methods=["GET"])
+async def all_users(request):
+    users = list(map(lambda u: u.serialize(), s.query(User).all()))
+    return json(users)
+
+
+@app.route("/user", methods=["POST"])
+async def new_user(request):
+    try:
+        s.add(User(**request.json))
+        return json({"success": True})
+    except Exception as e:
+        return json({"success": False})
+
+
+@app.route("/users/<user_id:int>", methods=["GET"])
+async def user(request, user_id):
+    try:
+        return json(s.query(User).filter_by(id=user_id)[0].serialize())
+    except IndexError:
+        raise NotFound("no user found with id: " + str(user_id))
+
+
+@app.exception(NotFound)
+async def not_found(request, exception):
+    return json({"type": type(exception).__name__, "message": str(exception)})
+
+
+app.run(host="0.0.0.0", port=8000)