Validators

Validators take a string and returns whether this string satisfies a set of rules. The most common application of this is for data types. Validators also capture state. For example, the Integer validator keeps track of the largest value it has seen.

Text

class baskerville.Text

Validates values as text and will therefore always succeed, collecting information on the longest seen value.

Example

>>> text = baskerville.Text()
>>> text.validate("42")
True
>>> text.validate("Ferris")
True

max_length

The maximum number of bytes of a value this validator has validated successfully.

Type:

int

min_length

The minimum number of bytes of a value this validator has validated successfully.

Type:

int

class baskerville.Literal(values)

Validates on literal values provided at creation. For example, you could match on the values True and False to implement a boolean type validator.

Parameters:

values (list[str]) -- List of literal values that will succeed.

Example

>>> boolean = baskerville.Literal(["True", "False"])
>>> boolean.validate("True")
True
>>> boolean.validate("Ferris")
False

Numeric

class baskerville.Integer

Represents a 128-bit signed integer and captures the largest and smallest values seen. These values can then be used to inform a more detailed inferred type. For example, if the minimum value is 0, then the field may be representable as an unsigned integer.

Example

>>> integer = baskerville.Integer()
>>> integer.validate("+42")
True
>>> integer.validate("Ferris")
False

leading_plus

Whether this validator has seen a value with a leading '+' sign.

Type:

bool

max_value

Maximum value that this validator has validated successfully.

Type:

int

min_value

Minimum value that this validator has validated successfully.

Type:

int

class baskerville.Float

Represents a 64-bit floating point number.

Example

>>> float_ = baskerville.Float()
>>> float_.validate("4.2")
True
>>> float_.validate("42")
True
>>> float_.validate("+42e-1")
True
>>> float_.validate("Ferris")
False

e_notation

Whether this validator has seen a value written in E notation.

Example

>>> float_ = baskerville.Float()
>>> float_.e_notation
False
>>> float_.validate("42e-1")
True
>>> float_.e_notation
True

Type:

bool

leading_plus

Whether this validator has seen a value with a leading '+' sign.

Type:

bool

max_value

Maximum value that this validator has validated successfully.

Type:

float

min_value

Minimum value that this validator has validated successfully.

Type:

float

Time

class baskerville.Date(formats=None)

Example:

>>> date = baskerville.Date()
>>> date.validate("2001-01-22")
True
>>> date.formats
['%Y-%m-%d']

formats

List of valid date strftime-like format strings

Note

This will clone the entire list and its elements when retrieved. Consider memoizing.

Type:

list[str]

class baskerville.Time(formats=None)

Example:

>>> time = baskerville.Time()
>>> time.validate("12:34:56")
True
>>> time.formats
['%H:%M:%S']

formats

List of valid time strftime-like format strings

Note

This will clone the entire list and its elements when retrieved. Consider memoizing.

Type:

list[str]

class baskerville.DateTime(formats=None)

Validates date-time values.

Parameters:

formats (Optional[list[DateTimeFormat]]) -- List of date-time formats.

Example

>>> date_time = baskerville.DateTime()
>>> date_time.validate("Mon, 22 Jan 2001 00:00:00 GMT")
True
>>> date_time.formats
[RFC2822]
>>> date_time = baskerville.DateTime(formats=[baskerville.DateTimeFormat.Unix])
>>> date_time.validate("980121600")
True
>>> date_time.validate("Ferris")
False

formats

List of valid date-time formats

Note

This will clone the entire list and its elements when retrieved. Consider memoizing.

Type:

list[DateTimeFormat]

class baskerville.DateTimeFormat

RFC2822 = RFC2822

RFC3339 = RFC3339

static Strftime(strftime)

Parameters:

strftime (str) --

Strftime-like format string.

Unix = Unix

Other

class baskerville.Empty

Validates empty values.

Example

>>> empty = baskerville.Empty()
>>> empty.validate("")
True
>>> empty.validate("Ferris")
False

class baskerville.Unique

Validates unique values. If the validator has seen a given value before, then it will fail to validate.

Example

>>> unique = baskerville.Unique()
>>> unique.validate("Ferris")
True
>>> unique.validate("Corro")
True
>>> unique.validate("Ferris")
False