Welcome to Flask-Validator’s documentation!¶

Data validator for Flask using SQL-Alchemy, working at Model component with events, preventing invalid data in the columns. The extension works with event listeners from SQLAlchemy.

The code is available in this repository

Contents:

Installation¶

Flask-Validator is avalable via pip, running the following command

pip install flask_validator

It might take a minute or so, it has quite a few things to download and install.

Basic Usage¶

The most performant way to set up your validations is uring the SQLAlchemy special directive __declare_last__, it occurs after mappings are assumed to be completed and the ‘configure’ step has finished. With this method, you will create the event one tine, just before the class creation.

The only required argument is the Column to validate.

# import ...
from flask_validator import ValidateInteger, ValidateString, ValidateEmail

class User(db.Model):
  _tablename__ = 'user'
  id = db.Column(db.Integer, primary_key=True)
  name = db.Column(db.String(80))
  code = db.Column(db.Integer())
  email = db.Column(db.String(125))

  def __init__(self, string, integer):
      self.string = string
      self.integer = integer

  @classmethod
  def __declare_last__(cls):
      ValidateString(User.name)
      ValidateInteger(User.code)
      ValidateEmail(User.email, true, true, "The e-mail is not valid. Please check it")

With that code, the Validator will execute an ORM event listening each field modification

Validators availables¶

At the moment, the library support this validations:

Types
Numeric
- Validatelength
- ValidateNumber
Comparision
Internet
Location
Financial
- ValidateCreditCard
- ValidateCurrency
- in_iban
- in_bic
Others

ValidateInteger¶

Check if the new value is a valid int or long type

Parametes:

Parameter	Default	Description
field		SQLAlchemy column to validate
allow_null	True	Allow `null` values
throw_exception	False	Throw a `ValidateError` exception on validation fails
message	None	Add a custom message to the `ValidateError` exception

Note

long type is only available i Python 2.7

ValidateNumeric¶

Check if the new value is a valid int, long, float or complex type

Parametes:

Parameter	Default	Description
field		SQLAlchemy column to validate
allow_null	True	Allow `null` values
throw_exception	False	Throw a `ValidateError` exception on validation fails
message	None	Add a custom message to the `ValidateError` exception

Note

long type is only available i Python 2.7

ValidateString¶

Check if the new value is a valid string type.

Parametes:

Parameter	Default	Description
field		SQLAlchemy column to validate
allow_null	True	Allow `null` values
throw_exception	False	Throw a `ValidateError` exception on validation fails
message	None	Add a custom message to the `ValidateError` exception

ValidateBoolean¶

Check if the new value is a valid bool type.

Parametes:

Parameter	Default	Description
field		SQLAlchemy column to validate
throw_exception	False	Throw a `ValidateError` exception on validation fails
message	None	Add a custom message to the `ValidateError` exception

Validatelength¶

Check if the new value has a length with a maximun and a minimun

Parametes:

Parameter	Default	Description
field		SQLAlchemy column to validate
max_length	None	Maximum value length
min_length	0	Minumum value length
throw_exception	False	Throw a `ValidateError` exception on validation fails
message	None	Add a custom message to the `ValidateError` exception

ValidateNumber¶

Check if the new value is a number or not (NaN)

Parametes:

Parameter	Default	Description
field		SQLAlchemy column to validate
throw_exception	False	Throw a `ValidateError` exception on validation fails
message	None	Add a custom message to the `ValidateError` exception

ValidateLessThan¶

Check if the new value is a lesser than X value

Parametes:

Parameter	Default	Description
field		SQLAlchemy column to validate
value		Value to check
throw_exception	False	Throw a `ValidateError` exception on validation fails
message	None	Add a custom message to the `ValidateError` exception

ValidateLessThanOrEqual¶

Check if the new value is a lesser than X value or equal

Parametes:

Parameter	Default	Description
field		SQLAlchemy column to validate
value		Value to check
throw_exception	False	Throw a `ValidateError` exception on validation fails
message	None	Add a custom message to the `ValidateError` exception

ValidateGreaterThan¶

Check if the new value is a greater than X value

Parametes:

Parameter	Default	Description
field		SQLAlchemy column to validate
value		Value to check
throw_exception	False	Throw a `ValidateError` exception on validation fails
message	None	Add a custom message to the `ValidateError` exception

ValidateGreaterThanOrEqual¶

Check if the new value is a greater than X value or equal

Parametes:

Parameter	Default	Description
field		SQLAlchemy column to validate
value		Value to check
throw_exception	False	Throw a `ValidateError` exception on validation fails
message	None	Add a custom message to the `ValidateError` exception

ValidateEmail¶

Check if the new value is a valid e-mail, using email_validator library.

Parametes:

Parameter	Default	Description
field		SQLAlchemy column to validate
allow_smtputf8	True	Allow internationalized addresses that would require the SMTPUTF8 extension.
check_deliverability	True	Check domain name resolution.
allow_empty_local	False	Allow an empty local part for validating Postfix aliases.
allow_null	True	Allow `null` values
throw_exception	False	Throw a `ValidateError` exception on validation fails
message	None	Add a custom message to the `ValidateError` exception

ValidateRegex¶

Compare a value against a regular expresion

Parametes:

Parameter	Default	Description
field		SQLAlchemy column to validate
throw_exception	False	Throw a `ValidateError` exception on validation fails
message	None	Add a custom message to the `ValidateError` exception

ValidateRange¶

Check if the new value is in a range

Parametes:

Parameter	Default	Description
field		SQLAlchemy column to validate
range		Range values
allow_null	True	Allow `null` values
throw_exception	False	Throw a `ValidateError` exception on validation fails
message	None	Add a custom message to the `ValidateError` exception

ValidateIP¶

Check if the value is a valid IP Address

Parametes:

Parameter	Default	Description
field		SQLAlchemy column to validate
ipv6	False	Check IPv6 Address instread of IPv4
allow_null	True	Allow `null` values
throw_exception	False	Throw a `ValidateError` exception on validation fails
message	None	Add a custom message to the `ValidateError` exception

ValidateURL¶

Check if the value is a valid URL

Parametes:

Parameter	Default	Description
field		SQLAlchemy column to validate
allow_null	True	Allow `null` values
throw_exception	False	Throw a `ValidateError` exception on validation fails
message	None	Add a custom message to the `ValidateError` exception

ValidateUUID¶

Check if the value is a valid UUUID

Parametes:

Parameter	Default	Description
field		SQLAlchemy column to validate
version	4	UUID version
allow_null	True	Allow `null` values
throw_exception	False	Throw a `ValidateError` exception on validation fails
message	None	Add a custom message to the `ValidateError` exception

ValidateCountry¶

Check if the value is a valid Country. Validation provided by iso3166. Allowed names:

Name
Alpha2
Alpha3
Numeric
Apolitic Name

Parametes:

Parameter	Default	Description
field		SQLAlchemy column to validate
allow_null	True	Allow `null` values
throw_exception	False	Throw a `ValidateError` exception on validation fails
message	None	Add a custom message to the `ValidateError` exception

ValidateTimezone¶

Check if the value is a valid Timezone. Validation provided by pytz

Parametes:

Parameter	Default	Description
field		SQLAlchemy column to validate
allow_null	True	Allow `null` values
throw_exception	False	Throw a `ValidateError` exception on validation fails
message	None	Add a custom message to the `ValidateError` exception

ValidateLocale¶

Check if the value is a valid Locale.

Parametes:

Parameter	Default	Description
field		SQLAlchemy column to validate
allow_null	True	Allow `null` values
throw_exception	False	Throw a `ValidateError` exception on validation fails
message	None	Add a custom message to the `ValidateError` exception

ValidateCreditCard¶

Check if the new value is valid credit card number.

Allowed formats: * XXXXYYYYWWWWZZZ * “XXXXYYYYWWWWZZZ” * “XXXX YYYY WWWW ZZZ” * “XXXX-YYYY-WWWW-ZZZ”

Parametes:

Parameter	Default	Description
field		SQLAlchemy column to validate
allow_null	True	Allow `null` values
throw_exception	False	Throw a `ValidateError` exception on validation fails
message	None	Add a custom message to the `ValidateError` exception

ValidateCurrency¶

Check if the new value is a valid Currency

Validation provided by: moneyed

Parametes:

Parameter	Default	Description
field		SQLAlchemy column to validate
allow_null	True	Allow `null` values
throw_exception	False	Throw a `ValidateError` exception on validation fails
message	None	Add a custom message to the `ValidateError` exception

ValidateIBAN¶

Check if the new value is valid IBAN (International Bank Account Number)

More reference: https://en.wikipedia.org/wiki/International_Bank_Account_Number

Parametes:

Parameter	Default	Description
field		SQLAlchemy column to validate
allow_null	True	Allow `null` values
throw_exception	False	Throw a `ValidateError` exception on validation fails
message	None	Add a custom message to the `ValidateError` exception

ValidateBIC¶

Check if the new value is valid BIC (SO 9362 defined standard format of Bank Identifier Codes )

More reference: https://en.wikipedia.org/wiki/ISO_9362

Parametes:

Parameter	Default	Description
field		SQLAlchemy column to validate
allow_null	True	Allow `null` values
throw_exception	False	Throw a `ValidateError` exception on validation fails
message	None	Add a custom message to the `ValidateError` exception

ValidateISBN¶

Check if the new value is valid ISBN (International Standard Book Number). Allows ISBN10 or ISBN13

Validation provided by: isbnlib More reference: https://en.wikipedia.org/wiki/International_Standard_Book_Number

Parametes:

Parameter	Default	Description
field		SQLAlchemy column to validate
allow_null	True	Allow `null` values
throw_exception	False	Throw a `ValidateError` exception on validation fails
message	None	Add a custom message to the `ValidateError` exception

Custom Validators¶

You will be able to create customs validator implementing the class Validator.

You must define your own method check_value() and if you are receiving any argument, you also must call the parent __init__()

from flask_validator import Validator

class ValidateAorB(Validator)
    def __init__(self, field, useless, allow_null=True, throw_exception=False, message=None):
        self.useless = useless

        Validator.__init__(self, field, allow_null, throw_exception, message):

    def check_value(self, value):
        return if value in ['A', 'B']


validator = ValidateAorB(field, True, True, 'yadayada')

Exception Message¶

You will be able to create customs exception messages, with a few variables availables:

field: Object and property
key: property
new_value: New value changed
old_value: Previous value

from flask_validator import ValidateEmail

validator = ValidateEmail(field, False, True, 'Message: Field {field}, Key {key}, New value {new_value}, Old value {old_value}')

Welcome to Flask-Validator’s documentation!¶

Installation¶

Basic Usage¶

Validators availables¶

ValidateInteger¶

ValidateNumeric¶

ValidateString¶

ValidateBoolean¶

Validatelength¶

ValidateNumber¶

ValidateLessThan¶

ValidateLessThanOrEqual¶

ValidateGreaterThan¶

ValidateGreaterThanOrEqual¶

ValidateEmail¶

ValidateRegex¶

ValidateRange¶

ValidateIP¶

ValidateURL¶

ValidateUUID¶

ValidateCountry¶

ValidateTimezone¶

ValidateLocale¶

ValidateCreditCard¶

ValidateCurrency¶

ValidateIBAN¶

ValidateBIC¶

ValidateISBN¶

Custom Validators¶

Exception Message¶

Indices and tables¶