recipemd.filter module

Defines boolean predicates that can be evaluated against a recipe.

Filters allow easy searching within the structure of a recipemd.data.Recipe. They can be created from strings with the FilterParser or in code with the FilterBuilder which can be imported as f from this module.

class recipemd.filter.FilterParser

Bases: object

Allows parsing filter strings into ASTs

filter_expression_parser: ParserElement

parse_filter_string(filter_string)

Parses a filter string into an evaluateable AST.

>>> fp = FilterParser()
>>> fp.parse_filter_string('vegan and summer')
BooleanAndOperation(operands=[AnyFilterTerm(filter_string=FuzzyFilterString(string='vegan')), AnyFilterTerm(filter_string=FuzzyFilterString(string='summer'))])

Parameters:

filter_string (str) – A string representing a recipe filter

Return type:

_FilterElement

Returns:

filter_element: A filter ast, subclass of FilterElement

Raises:

• ParseBaseException – If string is not a valid filter

• re.error – If a regular expression used in a filter term is not syntactically correct

recipemd.filter.f(string) = FilterBuilder(term=None)

A preconfigured FilterBuilder for convenient use

Parameters:

term (Optional[Type[FilterTerm]]) –

class recipemd.filter.FilterBuilder(term=None)

Bases: _FilterTermBuilder

Creates filter expressions in code

Allows using a language similar to the expressions parsed by recipemd.filter.FilterParser directly in python code. This makes filters usable as an embedded domain specific language.

A preconfigured Filter builder is available as f in this module:

>>> f('Cheese')
AnyFilterTerm(filter_string=FuzzyFilterString(string='Cheese'))

>>> f.ingr('Cheese')
IngredientFilterTerm(filter_string=FuzzyFilterString(string='Cheese'))

>>> f.re('Cheese|Bacon')
AnyFilterTerm(filter_string=RegexFilterString(regex=re.compile('Cheese|Bacon')))

>>> f.tag.ex('vegan')
TagFilterTerm(filter_string=ExactFilterString(string='vegan'))

Filters can be combined with logical operators “&” (and), “|” (or), “^” (xor), and “~” (not):

>>> f('Cheese') | f('Bacon')
BooleanOrOperation(operands=[AnyFilterTerm(filter_string=FuzzyFilterString(string='Cheese')), AnyFilterTerm(filter_string=FuzzyFilterString(string='Bacon'))])

Parameters:

term (Optional[Type[FilterTerm]]) –

property any: _FilterTermBuilder

Create a filter that matches any supported fields

Return type:

_FilterTermBuilder

property tag: _FilterTermBuilder

Create a filter that matches tags

Return type:

_FilterTermBuilder

property ingr: _FilterTermBuilder

Create a filter that matches ingredient names

Return type:

_FilterTermBuilder

property unit: _FilterTermBuilder

Create a filter that matches units in ingredients or in yields

Return type:

_FilterTermBuilder

class recipemd.filter.BooleanAndOperation(operands)

Bases: _BooleanBinaryOperation

Parameters:

operands (List[_FilterElement]) –

evaluate(recipe)

Evaluate filter against given recipe

Parameters:

recipe (Recipe) –

Return type:

bool

class recipemd.filter.BooleanOrOperation(operands)

Bases: _BooleanBinaryOperation

Parameters:

operands (List[_FilterElement]) –

evaluate(recipe)

Evaluate filter against given recipe

Parameters:

recipe (Recipe) –

Return type:

bool

class recipemd.filter.BooleanNotOperation(operands)

Bases: _BooleanUnaryOperation

Parameters:

operands (List[_FilterElement]) –

evaluate(recipe)

Evaluate filter against given recipe

Parameters:

recipe (Recipe) –

Return type:

bool

class recipemd.filter.BooleanXorOperation(operands)

Bases: _BooleanBinaryOperation

Parameters:

operands (List[_FilterElement]) –

OPERATOR = 'xor'

evaluate(recipe)

Evaluate filter against given recipe

Parameters:

recipe (Recipe) –

Return type:

bool

class recipemd.filter.AnyFilterTerm(filter_string)

Bases: IngredientFilterTerm, TagFilterTerm, UnitFilterTerm

Parameters:

filter_string (_FilterString) –

evaluate(recipe)

Evaluate filter against given recipe

Parameters:

recipe (Recipe) –

Return type:

bool

class recipemd.filter.TagFilterTerm(filter_string)

Bases: FilterTerm

Parameters:

filter_string (_FilterString) –

evaluate(recipe)

Evaluate filter against given recipe

Parameters:

recipe (Recipe) –

Return type:

bool

class recipemd.filter.IngredientFilterTerm(filter_string)

Bases: FilterTerm

Parameters:

filter_string (_FilterString) –

evaluate(recipe)

Evaluate filter against given recipe

Parameters:

recipe (Recipe) –

Return type:

bool

class recipemd.filter.UnitFilterTerm(filter_string)

Bases: FilterTerm

Parameters:

filter_string (_FilterString) –

evaluate(recipe)

Evaluate filter against given recipe

Parameters:

recipe (Recipe) –

Return type:

bool

class recipemd.filter.FuzzyFilterString(string)

Bases: _FilterString

Parameters:

string (str) –

string: str

contained_in(to_search)

Checks if any of the elements in to_search match the filter string.

Parameters:

to_search (Iterable[str]) –

Return type:

bool

class recipemd.filter.ExactFilterString(string)

Bases: _FilterString

Parameters:

string (str) –

string: str

contained_in(to_search)

Checks if any of the elements in to_search match the filter string.

Parameters:

to_search (Iterable[str]) –

Return type:

bool

class recipemd.filter.RegexFilterString(regex)

Bases: _FilterString

Parameters:

regex (Pattern) –

regex: Pattern

contained_in(to_search)

Checks if any of the elements in to_search match the filter string.

Parameters:

to_search (Iterable[str]) –

Return type:

bool