Class: Craft

Inherits:
Object
  • Object
show all
Defined in:
lib/craft.rb,
lib/craft/version.rb

Overview

Craft objects out of HTML and XML.

Examples

module Transformations
  IntegerTransform = lambda { |n| Integer n.text }
  Timestamp        = lambda { Time.now }
end

class Person < Craft
  include Transformations

  one :name, 'div.name'
  one :age, 'div.age', IntegerTransform
  many :friends, 'li.friend', Person
  stub :created_at, Timestamp
end

Constant Summary collapse

VERSION = 
'0.1.0'

Class Attribute Summary collapse

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(node, parent = nil) ⇒ Craft

Craft a new object.

node - A Nokogiri::XML::Node.



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# File 'lib/craft.rb', line 113

def initialize(node, parent = nil)
  @node = node
  @parent = parent
end

Class Attribute Details

.attribute_names ⇒ Object (readonly)

Returns an Array of names for the attributes defined in the class.



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# File 'lib/craft.rb', line 25

def attribute_names
  @attribute_names
end

Instance Attribute Details

#parent ⇒ Object (readonly)

Returns the value of attribute parent.



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# File 'lib/craft.rb', line 108

def parent
  @parent
end

Class Method Details

.many(name, *paths) ⇒ Object

Define an attribute that extracts a collection of values from a parsed document.

name - The Symbol name of the attribute. paths - One or more String XPath of CSS queries. An optional Proc

transformation on the extracted value may be appended. If none is
appended, the default transformation returns the stripped String
value of the node.

Returns nothing.



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# File 'lib/craft.rb', line 37

def many(name, *paths)
  transform = pop_transform_from_paths paths
  @attribute_names << name

  define_method name do
    @node.search(*paths).map { |node| instance_exec node, &transform }
  end
end

.one(name, *paths) ⇒ Object

Define an attribute that extracts a single value from a parsed document.

name - The Symbol name of the attribute. paths - One or more String XPath of CSS queries. An optional Proc

transformation on the extracted value may be appended. If none is
appended, the default transformation returns the stripped String
value of the node.

Returns nothing.



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# File 'lib/craft.rb', line 55

def one(name, *paths)
  transform = pop_transform_from_paths paths
  @attribute_names << name

  define_method name do
    instance_exec @node.at(*paths), &transform
  end
end

.parse(body) ⇒ Object

Parse a document.

body - A String HTML or XML document.

Returns an instance of its self.



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# File 'lib/craft.rb', line 69

def parse(body)
  new Nokogiri body
end

.stub(name, value = nil) ⇒ Object

Define an attribute that returns a value without parsing the document.

name - The Symbol name of the attribute. value - Some value the attribute should return. If given a Proc, the

value will be generated dynamically (default: nil).

Returns nothing.



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# File 'lib/craft.rb', line 80

def stub(name, value = nil)
  @attribute_names << name

  define_method name do
    value.respond_to?(:call) ? instance_exec(&value) : value
  end
end

.to_proc ⇒ Object 



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# File 'lib/craft.rb', line 88

def to_proc
  klass = self
  ->(node) { klass.new node, self }
end

Instance Method Details

#attribute_names ⇒ Object

Returns an Array of names for the attributes on this object.



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# File 'lib/craft.rb', line 124

def attribute_names
  self.class.attribute_names
end

#attributes ⇒ Object

Returns the Hash attributes.



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# File 'lib/craft.rb', line 119

def attributes
  Hash[attribute_names.map { |key| [key, self.send(key)] }]
end