一、参数传递
测试代码
# -*- coding: utf-8 -*- from flask import Flask, request app = Flask(__name__) @app.route("/", methods=['POST', 'GET']) def index(): print(request.args) print(request.form) print(request.values) print(request.data) print(request.json) return "ok" if __name__ == '__main__': app.run(debug=True)
请求测试
1、发送json数据
POST http://127.0.0.1:5000/?age=12 Content-Type: application/json { "name": "Tom" }
收到的数据如下
request.args [('age', '12')] request.form [] request.values [('age', '12')] request.data b'{\n"name": "Tom"\n}' request.json {'name': 'Tom'}
2、发送form数据
POST http://127.0.0.1:5000/?age=12 Content-Type: application/x-www-form-urlencoded name=Tom
收到的数据如下
request.args [('age', '12')] request.form [('name', 'Tom')] request.values [('age', '12'), ('name', 'Tom')] request.data b'' request.json None
如果request.args 和 request.form 数据相同，会优先取request.args 中的数据
二、升级参数接收
通过测试发现，如果前端没有传递正确的json数据，request.json 会返回一个None ,如果直接取数据会报错，目前主流的传参方式是json数据，我们改装一下：
# -*- coding: utf-8 -*- from flask import Flask, request, Request class MyRequest(Request): @property def json(self): """避免json数据未传递而返回 None""" try: data = self.get_json() except Exception as e: data = None return data or {} @property def params(self): """ 将参数全都放入一个变量 参数获取顺序 args > form > json :return: {dict} """ data = {} for key, value in self.args.items(): data.setdefault(key, value) for key, value in self.form.items(): data.setdefault(key, value) for key, value in self.json.items(): data.setdefault(key, value) return data app = Flask(__name__) app.request_class = MyRequest @app.route("/", methods=['POST', 'GET']) def index(): print(request.args) print(request.form) print(request.values) print(request.data) print(request.json) print(request.params) return request.params if __name__ == '__main__': app.run(debug=True)
MyRequest 类 修改了 json 方法，捕获了异常，避免返回 None 报错，添加了params 方法，将所有参数都封装到里边，简化参数获取，不过不能准确获取参数
三、返回参数
视图函数不能直接返回 list 参数，所以改造一下
# -*- coding: utf-8 -*- from flask import Flask, request, Request, jsonify class MyRequest(Request): @property def json(self): """避免json数据未传递而返回 None""" try: data = self.get_json() except Exception as e: data = None return data or {} @property def params(self): """ 将参数全都放入一个变量 处理参数顺序 args > form > json :return: {dict} """ data = {} for key, value in self.args.items(): data.setdefault(key, value) for key, value in self.form.items(): data.setdefault(key, value) for key, value in self.json.items(): data.setdefault(key, value) return data class MyFlask(Flask): request_class = MyRequest def make_response(self, rv): """视图函数可以直接返回list 或者 dict""" if isinstance(rv, (list, dict)): return jsonify(rv) return super().make_response(rv) def post(self, rule, **options): """便于书写post方法""" options.setdefault('methods', ['POST']) return self.route(rule, **options) app = MyFlask(__name__) @app.post("/") def index(): return ['cat', 'pig'] if __name__ == '__main__': app.run(debug=True)
额外添加了post方法，便于书写post请求
