flask修改flask_wtf使其支持json数据的validation验证

Posted 2020-11-27 花名k

flask默认是前后端不分离策略,前端通过flask+wtf表单来传递post,put...等数据.

 

现在前后端分离是趋势,那么对flask进行一定的修改,变为前后端分离,在前端页面中请求后端,那么请求的格式那么必然会有使用json传递数据,然而flask_wtf默认只支持form表单,那么对改动支持json

 

代码如下:

 1 # coding=utf-8
 2 
 3 from flask import request
 4 from wtforms import Form
 5 from OnlineClassroom.app.err.JsonValidateErr import JsonValidateErr
 6 
 7 
 8 # request data 基础验证器
 9 class RequestBaseForm(Form):
10     # 解析请求参数
11     def __init__(self):
12         # todo 做个处理,如果请求进来的请求时form参数则else,如果是json则进行下列操作
13         if "application/json" in request.headers.get("Content-Type"):
14             data = request.get_json(silent=True)
15             args = request.args.to_dict()
16             super(RequestBaseForm, self).__init__(data=data, **args)
17         else:
18             # application/x-www-form-urlencoded    or    multipart/form-data
19             data = request.form.to_dict()
20             args = request.args.to_dict()
21             super(RequestBaseForm, self).__init__(data=data, **args)
22 
23     # 对验证错误的参数抛出异常
24     def validate_for_api(self):
25         valid = super(RequestBaseForm, self).validate()
26         if not valid:
27             # todo 这里做一个返回,code,msg,data 错误返回  ???
28             raise JsonValidateErr("field is require?")
29 
30         return self

根据请求header中content-type来对数据解析,调用wtfforms的Form父类方法__init__将解析过后的参数给予父类的属性,其中自定义方法validate_for_api调用父类的验证方法validate()由父类来确定是否存在与准确

 

form表单模型:

1 # coding=utf-8
2 
3 from .JsonBaseValidate import RequestBaseForm
4 from wtforms import StringField,Form
5 from wtforms.validators import DataRequired,Length
6 
7 class Testform(RequestBaseForm):
8     username = StringField("username",validators=[DataRequired(),Length(min=2,max=20)])

---

一个简单的测试,路由代码如下:

1 @user.route("/index",methods=["GET","POST"])
2 def xx():
3     req = Testform()
4     type = request.headers.get("Content-Type")
5     if req.validate_for_api():
6         return "requset username.data {} >> request context-type {}".format(req.username.data,type)
7     return "request validate failds..."

 

 

 

 这是json请求,不要忘记在header中将content-type的选项改为applocation/json

 

 

 

 

这是form-data和form-urlencoded