Flask wtf validators Length min and max does not works-CodePudding

I build Flask app with sqlite3 database and app.route add and app.route save

I have a problem with validators some of them works some does not works validators.DataRequired() works URLField() works

but validators.Length(min=1,max=15) does not works at all


from flask_wtf import FlaskForm #I aslo I also tried with Form
from wtforms import BooleanField, StringField, IntegerField, validators,SubmitField
from wtforms.fields.html5 import URLField

class AddRecValidators(FlaskForm): # <---I aslo I also tried with Form

    title = StringField('Title:',[validators.DataRequired(), validators.Length(min=1,max=35,message="Title too long max 35 characters")])
    authors = StringField('Authors:',[validators.Length(min=1,max=100)])
    published_date = IntegerField('Published date:',[validators.Length(min=1,max=4)])
    isbn_or_identifier = StringField('ISBN:',[validators.Length(min=1,max=15)])
    page_count = IntegerField('Page count:',[ validators.Length(min=1,max=10000)])
    language = StringField('Language:',[ validators.Length(min=1,max=3)])
    image_links = URLField('Image links:')
    
    submit = SubmitField(label=('Add to library'))

CodePudding user response：

It looks like you're using the wrong validators for the type of input you're validating.

validators.Length() is for strings, see here
For the integers, try using NumberRange

from flask_wtf import FlaskForm
from wtforms import BooleanField, StringField, IntegerField, validators,SubmitField
from wtforms.fields.html5 import URLField

class AddRecValidators(FlaskForm): 

    title = StringField('Title:',[validators.DataRequired(), validators.Length(min=1,max=35,message="Title too long max 35 characters")])
    authors = StringField('Authors:',[validators.Length(min=1,max=100)])
    published_date = IntegerField('Published date:',[validators.NumberRange(min=1,max=4)]) # <-- note change to NumberRange
    isbn_or_identifier = StringField('ISBN:',[validators.Length(min=1,max=15)])
    page_count = IntegerField('Page count:',[ validators.NumberRange(min=1,max=10000)]) # <-- note change to NumberRange
    language = StringField('Language:',[ validators.Length(min=1,max=3)])
    image_links = URLField('Image links:')
    
    submit = SubmitField(label=('Add to library'))

Also, here are the docs for flask-wtforms validators.

CodePudding user response：

Still nothing, even though my book database has the same limitations.

class My_library(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    title = db.Column(db.String(35))
    authors = db.Column(db.String(25))
    published_date = db.Column(db.Integer)
    isbn_or_identifier = db.Column(db.String(15), unique=True)
    page_count = db.Column(db.String(10000))
    language = db.Column(db.String(3))
    image_links = db.Column(db.String(500))

I can create database entries via / addrec book titles exceeding 35 characters authors length over 100 characters published date with dates over a million page count above 10,000

neither limiting the number of characters in the database nor validation gives anything I have no idea why?

Does anybody have an idea?