flask是Python编写的web微框架，我们可以通过flask快速实现web服务，下面来看看如何利用flask快速实现接口服务

安装

python环境必须有啊！这不是废话吗？！
通过pip来安装flask

pip install flask

show me the code

新建一个py文件

基本配置

# 创建一个flask对象,名字随意但一定要和下面的app对应
app = Flask(__name__) 

# 访问根路径
@app.route('/')
def main():
    return 'hello flask'
# 执行py文件时，运行flask对象
if __name__ == '__main__':
    app.run() 

执行py文件后，输出以下内容表示flask运行成功

* Serving Flask app "keepapp" (lazy loading)
 * Environment: production
   WARNING: Do not use the development server in a production environment.
   Use a production WSGI server instead.
 * Debug mode: off
 * Running on http://127.0.0.1:5000/ (Press CTRL+C to quit

当我们通过浏览器访问http://127.0.0.1:5000/

image.png

GET、POST

# methods数组中只存在GET，所以此请求只允许GET方式，path参数和方法的参数也要一致
@app.route('/users/<page>/<count>', methods=['GET'])
def get_user_list(page, count): 
       return {'page':page,'count':count}

# 如果需要从参数中获取对应的值，需要引入request
from flask import request
@app.route('/users', methods=['GET'])
def get_user_list2(page, count):
       page =  request.args.get("page") 
       count = request.args.get("count") 
       return {'page':page,'count':count}

# 支持GET和POST请求方式
@app.route('/users', methods=['GET','POST'])
def get_user_list2(page, count):
       #方式和get一样
       page =  request.args.get("page") 
       count = request.args.get("count") 
       return {'page':page,'count':count}

返回html

from flask import send_file

@app.route('/usermap')
def get_user_map():
    #本地需要存在一个html文件
    fileName = 'static/keepmap.html'
    return send_file(fileName)

值得注意的是，请求结果的返回类型必须是string, tuple, Response instance, WSGI callable
否则会出现以下异常提醒

The view function did not return a valid response.
The return type must be a string, tuple, Response instance, or WSGI callable, but it was a list.