update python_restful_api.py

Author: xianhu

README.md

@@ -38,6 +38,8 @@
 
 ### python_restful_api.py: 利用Python和Flask快速开发RESTful API
 
+### python_restful_api.py: RESTful API进阶: 连接数据库、添加参数、Token认证、返回代码说明等
+
 ### python_context.py: With语句和上下文管理器ContextManager
 ===================================================================================================
 

python_restful_api.py

@@ -4,72 +4,182 @@
 python_restful_api.py by xianhu
 """
 
-from flask import Flask
-from flask_restful import reqparse, abort, Api, Resource
+import sqlalchemy
+import sqlalchemy.orm
+import sqlalchemy.ext.declarative
+from flask import Flask, g
+from flask_restful import reqparse, Api, Resource
+from flask_httpauth import HTTPTokenAuth
 
+
+# Flask相关变量声明
 app = Flask(__name__)
 api = Api(app)
 
-ITEMS = {
- 'item1': {'name': 'Allen', 'age': 19},
- 'item2': {'name': 'Lily', 'age': 18},
- 'item3': {'name': 'James', 'age': 20},
+# 认证相关
+auth = HTTPTokenAuth(scheme="token")
+TOKENS = {
+ "fejiasdfhu",
+ "fejiuufjeh"
 }
 
 
-def abort_if_item_doesnt_exist(item_id):
- if item_id not in ITEMS:
- abort(404, message="Item {} doesn't exist".format(item_id))
+@auth.verify_token
+def verify_token(token):
+ if token in TOKENS:
+ g.current_user = token
+ return True
+ return False
 
 
-def get_new_item_id():
- for key in ITEMS:
- item_id = 'item' + str(int(key.strip('item')) + 1)
- if item_id not in ITEMS:
- return item_id
+# 数据库相关变量声明
+engine = sqlalchemy.create_engine("mysql+pymysql://username:password@ip/db_name", encoding="utf8", echo=False)
+BaseModel = sqlalchemy.ext.declarative.declarative_base()
 
 
-parser = reqparse.RequestParser()
-parser.add_argument('name', type=str, required=True, help='need name data')
-parser.add_argument('age', type=int, required=True, help='need age data')
+# 构建数据模型User
+class User(BaseModel):
+ __tablename__ = "Users"
+ __table_args__ = {
+ "mysql_engine": "InnoDB",
+ "mysql_charset": "utf8",
+ }
 
+ # 表结构,具体更多的数据类型自行百度
+ id = sqlalchemy.Column("id", sqlalchemy.Integer, primary_key=True, autoincrement=True)
+ name = sqlalchemy.Column("name", sqlalchemy.String(50), nullable=False)
+ age = sqlalchemy.Column("age", sqlalchemy.Integer, nullable=False)
 
-# 操作（put / get / delete）单一资源
-class Todo(Resource):
 
- def put(self, item_id):
- args = parser.parse_args()
- item = {'name': args['name'], 'age': args['age']}
- ITEMS[item_id] = item
- return item, 201
+# 构建数据模型的json格式
+def get_json(user):
+ return {"id": user.id, "name": user.name, "age": user.age}
+
+
+# 利用Session对象连接数据库
+DBSessinon = sqlalchemy.orm.sessionmaker(bind=engine)
+session = DBSessinon()
+BaseModel.metadata.drop_all(engine)
+BaseModel.metadata.create_all(engine)
+
+# RESTfulAPI的参数解析 -- put / post参数解析
+parser_put = reqparse.RequestParser()
+parser_put.add_argument("name", type=str, required=True, help="need name data")
+parser_put.add_argument("age", type=int, required=True, help="need age data")
+
+# RESTfulAPI的参数解析 -- get参数解析
+parser_get = reqparse.RequestParser()
+parser_get.add_argument("limit", type=int, required=False)
+parser_get.add_argument("offset", type=int, required=False)
+parser_get.add_argument("sortby", type=str, required=False)
 
- def get(self, item_id):
- abort_if_item_doesnt_exist(item_id)
- return ITEMS[item_id], 200
 
- def delete(self, item_id):
- abort_if_item_doesnt_exist(item_id)
- del ITEMS[item_id]
- return '', 204
+# 操作（put / get / delete）单一资源
+class Todo(Resource):
+ # 添加认证
+ decorators = [auth.login_required]
+
+ def put(self, user_id):
+ """
+ 更新用户数据: curl http://127.0.0.1:5000/users/1 -X PUT -d "name=Allen&age=20" -H "Authorization: token fejiasdfhu"
+ """
+ args = parser_put.parse_args()
+ user_ids_set = set([user.id for user in session.query(User.id)])
+ print(user_ids_set)
+
+ # 用户不存在，返回404
+ if user_id not in user_ids_set:
+ return None, 404
+
+ # 更新用户数据
+ user = session.query(User).filter(User.id == user_id)[0]
+ user.name = args["name"]
+ user.age = args["age"]
+ session.merge(user)
+ session.commit()
+
+ # 更新成功，返回201
+ return get_json(user), 201
+
+ def get(self, user_id):
+ """
+ 获取用户数据: curl http://127.0.0.1:5000/users/1 -X GET -H "Authorization: token fejiasdfhu"
+ """
+ users = session.query(User).filter(User.id == user_id)
+
+ # 用户不存在，返回404
+ if users.count() == 0:
+ return None, 404
+
+ # 返回用户数据
+ return get_json(users[0]), 200
+
+ def delete(self, user_id):
+ """
+ 删除用户数据: curl http://127.0.0.1:5000/users/1 -X DELETE -H "Authorization: token fejiasdfhu"
+ """
+ session.query(User).filter(User.id == user_id).delete()
+ return None, 204
 
 
 # 操作（post / get）资源列表
 class TodoList(Resource):
+ # 添加认证
+ decorators = [auth.login_required]
 
  def get(self):
- return ITEMS, 200
+ """
+ 获取全部用户数据: curl http://127.0.0.1:5000/users -X GET -d "limit=2&offset=0&sortby=name" -H "Authorization: token fejiasdfhu"
+ """
+ args = parser_get.parse_args()
+ users = session.query(User)
+
+ # 根据条件查询
+ if "sortby" in args:
+ users = users.order_by(User.name if args["sortby"] == "name" else User.age)
+ if "offset" in args:
+ users = users.offset(args["offset"])
+ if "limit" in args:
+ users = users.limit(args["limit"])
+
+ # 返回结果
+ return [get_json(user) for user in users], 200
 
  def post(self):
- args = parser.parse_args()
- item_id = get_new_item_id()
- ITEMS[item_id] = {'name': args['name'], 'age': args['age']}
- return ITEMS[item_id], 201
+ """
+ 添加一个新用户: curl http://127.0.0.1:5000/users -X POST -d "name=Brown&age=20" -H "Authorization: token fejiasdfhu"
+ """
+ args = parser_put.parse_args()
+
+ # 构建新用户
+ user = User(name=args["name"], age=args["age"])
+ session.add(user)
+ session.commit()
+
+ # 资源添加成功，返回201
+ return get_json(user), 201
 
 
 # 设置路由
-api.add_resource(TodoList, '/items')
-api.add_resource(Todo, '/items/<item_id>')
+api.add_resource(TodoList, "/users")
+api.add_resource(Todo, "/users/<int:user_id>")
 
 
-if __name__ == '__main__':
+if __name__ == "__main__":
  app.run(debug=True)
+
+
+""" 常见返回代码
+200 OK - [GET]：服务器成功返回用户请求的数据
+201 CREATED - [POST/PUT/PATCH]：用户新建或修改数据成功
+202 Accepted - [*]：表示一个请求已经进入后台排队（异步任务）
+204 NO CONTENT - [DELETE]：用户删除数据成功
+400 INVALID REQUEST - [POST/PUT/PATCH]：用户发出的请求有错误，服务器没有进行新建或修改数据的操作
+401 Unauthorized - [*]：表示用户没有权限（令牌、用户名、密码错误）
+403 Forbidden - [*] 表示用户得到授权（与401错误相对），但是访问是被禁止的
+404 NOT FOUND - [*]：用户发出的请求针对的是不存在的记录，服务器没有进行操作
+406 Not Acceptable - [GET]：用户请求的格式不可得
+410 Gone -[GET]：用户请求的资源被永久删除，且不会再得到的
+422 Unprocesable entity - [POST/PUT/PATCH] 当创建一个对象时，发生一个验证错误
+500 INTERNAL SERVER ERROR - [*]：服务器发生错误，用户将无法判断发出的请求是否成功
+"""