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String Rules

Length

Validator to check if the length of a string value falls within a specified range.

Parameters:
  • min_length (int): The minimum allowed length of the string.
  • max_length (int): The maximum allowed length of the string.
  • message (str): The error message to be used if the validation fails.
Example 
Length(5, 10) # Length(min_length=5, max_length=10)

MinLength

Validator to check if a value has a minimum length.

Parameters:
  • min (int): The minimum length that the value must have.
  • message (str): The error message to be used if the validation fails.
Example 
MinLength(5) # MinLength(min=5)

MaxLength

Validator to check if a value has a maximum length.

Parameters:
  • max (int): The maximum length that the value must have.
  • message (str): The error message to be used if the validation fails.
Example 
MaxLength(10) # MaxLength(max=10)

NotBlank

Validator to check if a string value is not blank (empty or contains only whitespace).

Parameters:
  • message (str): The error message to be used if the validation fails.
Example 
NotBlank()
# custom error message
NotBlank(message="Value should not be blank")

InList

Validator to check if a string value is present in a specified list.

Parameters:
  • valid_values (list): The list of valid values.
  • message (str): The error message to be used if the validation fails.
Example 
InList(["apple", "banana", "cherry"])
# custom error message
InList(["apple", "banana", "cherry"], "Value {field_name} should be one of: {valid_values}")

NotInList

Validator to check if a string value is not present in a specified list.

Parameters:
  • invalid_values (list): The list of invalid values.
  • message (str): The error message to be used if the validation fails.
Example 
NotInList(["apple", "banana", "cherry"])
# custom error message
NotInList(["apple", "banana", "cherry"], "Value {field_name} should not be one of: {valid_values}")

DoesntStartsWith

Validate that a string value does not start with any of the specified prefixes.

Parameters:
  • list_prefix (list of str): The list of prefixes that the string should not start with.
  • message (str): The error message template if validation fails.
Example 
DoesntStartsWith(["apple", "banana", "cherry"])
# custom error message
DoesntStartsWith(["apple", "banana", "cherry"], "Value {field_name} should not start with any of: {list_prefix}")

StartsWith

Validate that a string value does not start with any of the specified prefixes.

Parameters:
  • list_prefix (list of str): The list of prefixes that the string should not start with.
  • message (str): The error message template if validation fails.
Example 
StartsWith(["apple", "banana", "cherry"])
# custom error message
StartsWith(["apple", "banana", "cherry"], "Value {field_name} should start with any of: {list_prefix}")

DoesntEndsWith

Validate that a string value does not start with any of the specified prefixes.

Parameters:
  • list_prefix (list of str): The list of prefixes that the string should not start with.
  • message (str): The error message template if validation fails.
Example 
DoesntEndsWith(["apple", "banana", "cherry"])
# custom error message
DoesntEndsWith(["apple", "banana", "cherry"], "Value {field_name} should not end with any of: {list_prefix}")

EndsWith

Validate that a string value ends with one of the specified suffixes.

Parameters:
  • list_tail (list of str): The list of suffixes that the string should end with.
  • message (str): The error message template if validation fails.
Example 
EndsWith(["apple", "banana", "cherry"])
# custom error message
EndsWith(["apple", "banana", "cherry"], "Value {field_name} should end with any of: {list_tail}")

Equals

Validate that a string value is equal to another specified value.

Parameters:
  • another_value (str): The value to compare against.
  • message (str): The error message template if validation fails.
Example 
Equals("apple")
# custom error message
Equals("apple", "Value {field_name} should be equal to {another_value}")

NotEquals

Validate that a string value is not equal to another specified value.

Parameters:
  • another_value: The value to compare against.
  • message (str): The error message template if validation fails.
Example 
NotEquals("apple")
# custom error message
NotEquals("apple", "Value {field_name} should not be equal to {another_value}")