Module configurator.fields

Settings fields

"""Settings fields"""

from abc import ABC
from typing import Any
import re


class ValidationError(Exception):
    """
    Thrown when value for the Field didn't pass the validation.
    """


class Field(ABC):
    """
    Base Field type. All objects used as settings fields should be subclass of Field.
    """
    type_: type = object
    default: Any = None

    def __init__(self, required: bool = True, default: Any = None):
        """
        Creates new Field object.
        Args:
            required: set true if field is crucial for the project and should be always provided
            default: default field value if not specified in config
        """
        self.required = required
        if default is not None:
            self.default = self.validate(default)

    def validate(self, value: Any) -> Any:
        """
        Validate if value can be assign to the field.
        Checks if value's type is correct.
        Args:
            value: value to assign to the Field

        Returns:
            safe to assign value

        """
        if not isinstance(value, self.type_):
            raise ValidationError('Type mismatch')
        return value


class Integer(Field):
    """
    Class for number type fields.
    """
    type_ = int
    default = 0


class PositiveInteger(Integer):
    """
    Class for positive integers - natural numbers.
    """
    default = 1

    def validate(self, value: int) -> int:
        value = super().validate(value)
        if value <= 0:
            raise ValidationError('PositiveInteger value must be greater than 0.')
        return value


class String(Field):
    """
    Class for string type fields.
    """
    type_ = str
    default = ''


class Email(String):
    """
    Class for email fields.
    """

    def validate(self, value: str) -> str:
        """Validates email using simple regex."""
        value = super().validate(value)
        regex = re.compile(r'^\S+@\S+\.\S+$')
        if regex.fullmatch(value) is None:
            raise ValidationError('Provided string is not a valid email.')
        return value


class Boolean(Field):
    """
    Class for bool type fields.
    """
    type_ = bool
    default = False


class Float(Field):
    """
    Class for floating-point numbers.
    """
    type_ = float
    default = 0.0


class Url(String):
    """
    Class for url fields.
    """

    def validate(self, value: str) -> str:
        """Validates url using regular expression."""
        value = super().validate(value)
        regex = regex = re.compile(
            r'^https?://'  # http:// or https://
            r'(?:(?:[A-Z0-9](?:[A-Z0-9-]{0,61}[A-Z0-9])?\.)+[A-Z]{2,6}\.?|'  # domain...
            r'localhost|'  # localhost...
            r'\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})'  # ...or ip
            r'(?::\d+)?'  # optional port
            r'(?:/?|[/?]\S+)$', re.IGNORECASE)
        if regex.fullmatch(value) is None:
            raise ValidationError('Provided string is not a valid url.')
        return value

Classes

class Boolean (required: bool = True, default: Any = None)

Class for bool type fields.

Creates new Field object.

Args

required

set true if field is crucial for the project and should be always provided

default

default field value if not specified in config

Expand source code

class Boolean(Field):
    """
    Class for bool type fields.
    """
    type_ = bool
    default = False

Ancestors

• Field
• abc.ABC

Class variables

var default : Any

Inherited members

• Field:
  • type_
  • validate

class Email (required: bool = True, default: Any = None)

Class for email fields.

Creates new Field object.

Args

required

set true if field is crucial for the project and should be always provided

default

default field value if not specified in config

Expand source code

class Email(String):
    """
    Class for email fields.
    """

    def validate(self, value: str) -> str:
        """Validates email using simple regex."""
        value = super().validate(value)
        regex = re.compile(r'^\S+@\S+\.\S+$')
        if regex.fullmatch(value) is None:
            raise ValidationError('Provided string is not a valid email.')
        return value

Ancestors

• String
• Field
• abc.ABC

Methods

def validate(self, value: str) ‑> str

Validates email using simple regex.

Expand source code

def validate(self, value: str) -> str:
    """Validates email using simple regex."""
    value = super().validate(value)
    regex = re.compile(r'^\S+@\S+\.\S+$')
    if regex.fullmatch(value) is None:
        raise ValidationError('Provided string is not a valid email.')
    return value

Inherited members

• String:
  • type_

class Field (required: bool = True, default: Any = None)

Base Field type. All objects used as settings fields should be subclass of Field.

Creates new Field object.

Args

required

set true if field is crucial for the project and should be always provided

default

default field value if not specified in config

Expand source code

class Field(ABC):
    """
    Base Field type. All objects used as settings fields should be subclass of Field.
    """
    type_: type = object
    default: Any = None

    def __init__(self, required: bool = True, default: Any = None):
        """
        Creates new Field object.
        Args:
            required: set true if field is crucial for the project and should be always provided
            default: default field value if not specified in config
        """
        self.required = required
        if default is not None:
            self.default = self.validate(default)

    def validate(self, value: Any) -> Any:
        """
        Validate if value can be assign to the field.
        Checks if value's type is correct.
        Args:
            value: value to assign to the Field

        Returns:
            safe to assign value

        """
        if not isinstance(value, self.type_):
            raise ValidationError('Type mismatch')
        return value

Ancestors

• abc.ABC

Subclasses

• Boolean
• Float
• Integer
• String
• BaseSettings

Class variables

var default : Any

var type_ : type

The base class of the class hierarchy.

When called, it accepts no arguments and returns a new featureless instance that has no instance attributes and cannot be given any.

Methods

def validate(self, value: Any) ‑> Any

Validate if value can be assign to the field. Checks if value's type is correct.

Args

value

value to assign to the Field

Returns

safe to assign value

Expand source code

def validate(self, value: Any) -> Any:
    """
    Validate if value can be assign to the field.
    Checks if value's type is correct.
    Args:
        value: value to assign to the Field

    Returns:
        safe to assign value

    """
    if not isinstance(value, self.type_):
        raise ValidationError('Type mismatch')
    return value

class Float (required: bool = True, default: Any = None)

Class for floating-point numbers.

Creates new Field object.

Args

required

set true if field is crucial for the project and should be always provided

default

default field value if not specified in config

Expand source code

class Float(Field):
    """
    Class for floating-point numbers.
    """
    type_ = float
    default = 0.0

Ancestors

• Field
• abc.ABC

Class variables

var default : Any

Inherited members

• Field:
  • type_
  • validate

class Integer (required: bool = True, default: Any = None)

Class for number type fields.

Creates new Field object.

Args

required

set true if field is crucial for the project and should be always provided

default

default field value if not specified in config

Expand source code

class Integer(Field):
    """
    Class for number type fields.
    """
    type_ = int
    default = 0

Ancestors

• Field
• abc.ABC

Subclasses

• PositiveInteger

Class variables

var default : Any

Inherited members

• Field:
  • type_
  • validate

class PositiveInteger (required: bool = True, default: Any = None)

Class for positive integers - natural numbers.

Creates new Field object.

Args

required

set true if field is crucial for the project and should be always provided

default

default field value if not specified in config

Expand source code

class PositiveInteger(Integer):
    """
    Class for positive integers - natural numbers.
    """
    default = 1

    def validate(self, value: int) -> int:
        value = super().validate(value)
        if value <= 0:
            raise ValidationError('PositiveInteger value must be greater than 0.')
        return value

Ancestors

• Integer
• Field
• abc.ABC

Class variables

var default : Any

Inherited members

• Integer:
  • type_
  • validate

class String (required: bool = True, default: Any = None)

Class for string type fields.

Creates new Field object.

Args

required

set true if field is crucial for the project and should be always provided

default

default field value if not specified in config

Expand source code

class String(Field):
    """
    Class for string type fields.
    """
    type_ = str
    default = ''

Ancestors

• Field
• abc.ABC

Subclasses

• Email
• Url

Class variables

var default : Any

Inherited members

• Field:
  • type_
  • validate

class Url (required: bool = True, default: Any = None)

Class for url fields.

Creates new Field object.

Args

required

set true if field is crucial for the project and should be always provided

default

default field value if not specified in config

Expand source code

class Url(String):
    """
    Class for url fields.
    """

    def validate(self, value: str) -> str:
        """Validates url using regular expression."""
        value = super().validate(value)
        regex = regex = re.compile(
            r'^https?://'  # http:// or https://
            r'(?:(?:[A-Z0-9](?:[A-Z0-9-]{0,61}[A-Z0-9])?\.)+[A-Z]{2,6}\.?|'  # domain...
            r'localhost|'  # localhost...
            r'\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})'  # ...or ip
            r'(?::\d+)?'  # optional port
            r'(?:/?|[/?]\S+)$', re.IGNORECASE)
        if regex.fullmatch(value) is None:
            raise ValidationError('Provided string is not a valid url.')
        return value

Ancestors

• String
• Field
• abc.ABC

Methods

def validate(self, value: str) ‑> str

Validates url using regular expression.

Expand source code

def validate(self, value: str) -> str:
    """Validates url using regular expression."""
    value = super().validate(value)
    regex = regex = re.compile(
        r'^https?://'  # http:// or https://
        r'(?:(?:[A-Z0-9](?:[A-Z0-9-]{0,61}[A-Z0-9])?\.)+[A-Z]{2,6}\.?|'  # domain...
        r'localhost|'  # localhost...
        r'\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})'  # ...or ip
        r'(?::\d+)?'  # optional port
        r'(?:/?|[/?]\S+)$', re.IGNORECASE)
    if regex.fullmatch(value) is None:
        raise ValidationError('Provided string is not a valid url.')
    return value

Inherited members

• String:
  • type_

class ValidationError (*args, **kwargs)

Thrown when value for the Field didn't pass the validation.

Expand source code

class ValidationError(Exception):
    """
    Thrown when value for the Field didn't pass the validation.
    """

Ancestors

• builtins.Exception
• builtins.BaseException