Class: RecipeScrapers::Declaration

Inherits:
Object
  • Object
show all
Defined in:
lib/recipe_scrapers/declaration.rb

Overview

Tells the gem where the recipe fields are on a site whose markup is missing or wrong. A declaration is built by register. Inside its block, each recipe field is a method that takes a CSS selector:

  • title "h1.recipe-title" reads the text of the first match.
  • ingredients rows: "ul.ingredients li" reads one line per match, for ingredients, instructions, keywords and equipment.
  • ingredient_groups heading: "h3", item: "li" splits the ingredients under their headings.

A declared field wins over the schema.org value. Every field left out falls back to it.

Examples:

RecipeScrapers.register "example.com" do
  title "h1.recipe-title"
  ingredients rows: ".ingredients li"
  instructions rows: ".steps li"
  encoding "windows-1251"
end

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(host) ⇒ Declaration 



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# File 'lib/recipe_scrapers/declaration.rb', line 39

def initialize(host)
  @host = host
  @rules = {}
  @parsers = {}
  @encoding_name = nil
end

Instance Attribute Details

#encoding_name ⇒ String? (readonly) 



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# File 'lib/recipe_scrapers/declaration.rb', line 30

def encoding_name
  @encoding_name
end

#host ⇒ String (readonly) 



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# File 'lib/recipe_scrapers/declaration.rb', line 27

def host
  @host
end

Class Method Details

.build(host) { ... } ⇒ Declaration

Yields:

  • the declaration body, evaluated on the new declaration



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# File 'lib/recipe_scrapers/declaration.rb', line 35

def self.build(host, &block)
  new(host).tap { |declaration| declaration.instance_eval(&block) if block }
end

Instance Method Details

#encoding(name) ⇒ Object

Declares the encoding of pages that send no charset, or the wrong one.



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# File 'lib/recipe_scrapers/declaration.rb', line 58

def encoding(name)
  @encoding_name = name
end

#parser(field, *parsers) ⇒ Object

Sets the parsers of a field for this site, in the order they are tried.

Raises:

  • (ArgumentError) —

    for a field that takes no parser



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# File 'lib/recipe_scrapers/declaration.rb', line 67

def parser(field, *parsers)
  @parsers[Parsers::Chain.field!(field)] = parsers
end

#parsers_for(field) ⇒ Array<#call>?

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Returns the parsers this site sets for the field.



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# File 'lib/recipe_scrapers/declaration.rb', line 75

def parsers_for(field)
  @parsers[field]
end

#rule(field) ⇒ Hash?

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Returns what the declaration says about the field: {selector:}, {rows:}, or {heading:, item:} for ingredient groups.



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# File 'lib/recipe_scrapers/declaration.rb', line 51

def rule(field)
  @rules[field]
end