AttributeError: type object 'WXLoginForm' has no attribute 'from_json'
出现上面问题的百分之九十都是因为没写以下内容：
···
import wtforms_json
wtforms_json.init()
···
使用流程如下：
Quickstart
In order to start using WTForms-JSON, you need to first initialize the extension. This monkey patches some classes and methods within WTForms and adds JSON handling support:
First Example
After the extension has been initialized we can create an ordinary WTForms form. Notice how we are initalizing the form using from_json() class method:
class LocationForm(Form):
name = TextField()
address = TextField()
class EventForm(Form):
name = TextField()
is_public = BooleanField()
json = {
'name': 'First Event',
'location': {'name': 'some location'},
}
form = EventForm.from_json(json) # 此处调用了from_json,即可接收json对象
If you want WTForms-JSON to throw errors when unknown json keys are encountered just pass skip_unknown_keys=False to from_json():
Throws exception
form = EventForm.from_json(json, skip_unknown_keys=False)
最后的生产环境样例：
from flask import request
class EventForm(Form):
name = TextField()
is_public = BooleanField()
form = EventForm.from_json(class EventForm(Form):
name = TextField()
is_public = BooleanField()
form = EventForm.from_json(request.json)
我知道有蛋疼的哥们跟我遇到一样的问题，话不多说，喜欢点赞
