Python builds Mock_server based on Flask

1. Introduction

Flask is a lightweight and customizable framework, written in Python language, which is more flexible, lightweight, safe and easy to use than other similar frameworks. Flask is a micro-framework based on Python development and relies on jinja2 templates and Werkzeug WSGI services . Here we briefly introduce the use of flask to mock a server, which is convenient for testing and mock testing before the corresponding service function development is completed.

Install:

# 安装flask
pip install flask
# 验证flask
pip show flask

Two, Flask is simple to use

1. Configuration file

app=Flask(__name__,template_folder='templates',static_url_path='/static/',static

_path='/zz')

Template path: template_folder='templates'

Static file path: static_url_path='/static/'

Import aliases for static files: static_path='/zz'

Set to debug environment: app.debug=True (code modification is automatically updated)

2. Routing system

1) Dynamic routing (url parameter passing), the sample code is as follows:

from flask import Flask


# 创建1个Flask实例
app = Flask(__name__)


# 设置一个动态参数name
@app.route('/<name>')
# 视图必须有对应的接收参数name
def first_flask(name):
    print(name)
    return "Hello World~"


if __name__ == '__main__':
    app.run(debug=True)

 After executing the code, access the service link, add the name "yoyo" to the path, and the effect is as follows:

2) Specify the allowed request method

@app.route('/login', methods=['GET', 'POST'])

3. Request request parameter acquisition

1) Post request parameter acquisition

request.get_data(), request.data, get unprocessed raw request data regardless of the content type, if the data format is json, then get a json string; request.get_json(), and request.json
, The request parameters are processed, and the result is in dictionary format, so the sorting will disrupt the sorting rules based on the dictionary.

Client request code:

Server code:

from flask import Flask, request


# 创建1个Flask实例
app = Flask(__name__)


# 设置一个动态参数name
@app.route('/', methods=['GET', 'POST'])
# 视图函数
def first_flask():
    # 1. request.get_data()、request.data，获取未经处理过的原始请求数据而不管内容类型,如果数据格式是json的，则取得的是json字符串
    a = request.get_data()
    print(a)
    print(type(a))

    b = request.data
    print(b)
    print(type(b))

    # 2.request.get_json(),和request.json，将请求参数做了处理，得到的是字典格式的，因此排序会打乱依据字典排序规则
    c = request.get_json()
    print(c)
    print(type(c))
    name = request.get_json()['name']
    print(f"name的值是：{name}")

    d = request.json
    print(d)
    print(type(d))

    return "Hello World~"


if __name__ == '__main__':
    app.run(debug=True)

2) get request parameter acquisition

Client code:

Server code: 

from flask import Flask, request


# 创建1个Flask实例
app = Flask(__name__)


# 设置一个动态参数name
@app.route('/', methods=['GET', 'POST'])
# 视图函数
def first_flask():

    # get请求参数
    # 获取到单个的值
    e = request.args.get('name')
    print(f'获取name的值为：{e}')

    # 可以获取get请求的所有参数返回值是ImmutableMultiDict(不可变的多字典)类型
    f = request.args
    print(f)

    # 将获得的参数转换为字典
    g = request.args.to_dict()
    print(g)
    print(type(g))

    return "Hello World~"


if __name__ == '__main__':
    app.run(debug=True)

The server prints the result:

 There are also some common methods, such as:

request.headers : Get request headers

request.method: get method

request.url: Get the access url address, such as  http://127.0.0.1:5000/?name=yoyo&age=17

request.cookies: get request cookies

3. Mock login and query user information scenarios

Server code:

from flask import Flask, request, jsonify

app = Flask(__name__)
# 解决接收报文中文乱码问题
app.config['JSON_AS_ASCII'] =False


@app.route('/api/login', methods=['POST'], strict_slashes=False)
def login():
    '''登录接口'''
    # 调试信息，打印请求方法
    print(request.method)
    # 获取请求数据，将数据变为字典
    data = request.get_json()
    print(data)

    # 定义用户名和密码变量，从data中取值
    username = data['username']
    pwd = data['password']

    '''
    测试场景设计
    1）参数为空
    2）用户名密码正确
    3）用户名或密码错误
    '''
    if username == '' or pwd == '':
        return jsonify({"code": "001",
                        "msg": "用户名或密码不能为空"})

    elif username == 'yoyo' and pwd == '123456':
        return jsonify({"code": "002",
                        "msg": "登录成功",
                        "info": {
                            "age": 18,
                            "name": "yoyo"},
                        "token": "23657DGYUSGD126731638712GE18271H"
                        })
    else:
        return jsonify(
            {
                "code": "001",
                "msg": "用户名或密码错误"
            }
        )

# 查询个人用户信息接口
@app.route('/api/userinfo', methods=['GET'], strict_slashes=False)
def api_userinfo():
    # 获取请求头的token
    token = request.headers.get('token')
    if token == "23657DGYUSGD126731638712GE18271H":
        return jsonify({
            "httpstatus": 200,
            "data": {
                "userid": 321411,
                "username": "yoyo",
                "userbalance": 5678.90,
                "userpoints": 4215
            }
        })
    else:
        return jsonify(
            {"code": "1000",
             "msg": "用户信息不正确"}
        )


if __name__ == '__main__':
    app.run(debug=True)

illustrate:

1) # In the routing configuration, strict_slashes=False is strictly required for the / symbol at the end of the URL
    For example: @app.route('/index', strict_slashes=False) #Visit http://www.xx.com/index/ or http://www.xx.com/index is available
    @app.route('/index',strict_slashes=True) #Only visit http://www.xx.com/index 

2) In the Flask framework, jsonify can be used to return json data. When using jsonify, the Content-Type of the returned http response is application/json, which complies with the provisions of the HTTP protocol

Client code and request result: