I'm not able to perform validation for the input data in my mongoengine model class

Question

class TextBoxValues(DynamicDocument):
    entity_id = StringField(max_length=200, required=True) 
    textbox_type = StringField(max_length=1000, required=True)  
    regexp = re.compile('[A-Za-z]')
    entity_value = StringField(regex=regexp,max_length=None, required=True) 

I was using the regex parameter to perform validation which is not working for me,it still takes input in any format, why?

Answer 1

The regex to provide to StringField(regex=) should in fact be a string but it also work if you give it a compiled regex.

The problem is your regex actually. It should be regexp=r'^[A-Za-z]+$' as @wiktor-stribiżew suggested in the comment.

The minimal example below demonstrates that the regex works as expected

from mongoengine import *
connect()    # connect to 'test' database

class TextBoxValues(Document):
    entity_value = StringField(regex=r'^[A-Za-z]+$')

TextBoxValues(entity_value="AZaz").save() # passes validation

TextBoxValues(entity_value="AZaz1").save() # raises ValidationError (String value did not match validation regex: ['entity_value'])