Module: Rack::Accept::Header::PublicInstanceMethods

Included in:
Rack::Accept::Header
Defined in:
lib/rack/accept/header.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#qvalues ⇒ Object

A table of all values of this header to their respective quality factors (qvalues).



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# File 'lib/rack/accept/header.rb', line 67

def qvalues
  @qvalues
end

Instance Method Details

#accept?(value) ⇒ Boolean

Determines if the given value is acceptable (does not have a qvalue of 0) according to this header.

Returns:

  • (Boolean) 


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# File 'lib/rack/accept/header.rb', line 97

def accept?(value)
  qvalue(value) != 0
end

#best_of(values, keep_unacceptables = false) ⇒ Object

A shortcut for retrieving the first result of #sort.



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# File 'lib/rack/accept/header.rb', line 135

def best_of(values, keep_unacceptables=false)
  sort(values, keep_unacceptables).first
end

#initialize(header = '') ⇒ Object 



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# File 'lib/rack/accept/header.rb', line 69

def initialize(header='')
  @qvalues = parse(header)
end

#name ⇒ Object

The name of this header. Should be overridden in classes that mixin this module.



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# File 'lib/rack/accept/header.rb', line 75

def name
  ''
end

#qvalue(value) ⇒ Object

Returns the quality factor (qvalue) of the given value. Should be overridden in classes that mixin this module.



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# File 'lib/rack/accept/header.rb', line 81

def qvalue(value)
  1
end

#sort(values, keep_unacceptables = false) ⇒ Object

Sorts the given values according to the qvalue of each while preserving the original order. See #sort_with_qvalues for more information on exactly how the sort is performed.



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# File 'lib/rack/accept/header.rb', line 130

def sort(values, keep_unacceptables=false)
  sort_with_qvalues(values, keep_unacceptables).map {|q, v| v }
end

#sort_with_qvalues(values, keep_unacceptables = true) ⇒ Object

Returns a copy of the given values array, sorted by quality factor (qvalue). Each element of the returned array is itself an array containing two objects: 1) the value's qvalue and 2) the original value.

It is important to note that this sort is a "stable sort". In other words, the order of the original values is preserved so long as the qvalue for each is the same. This expectation can be useful when trying to determine which of a variety of options has the highest qvalue. If the user prefers using one option over another (for any number of reasons), he should put it first in values. He may then use the first result with confidence that it is both most acceptable to the client and most convenient for him as well.



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# File 'lib/rack/accept/header.rb', line 114

def sort_with_qvalues(values, keep_unacceptables=true)
  qvalues = {}
  values.each do |v|
    q = qvalue(v)
    if q != 0 || keep_unacceptables
      qvalues[q] ||= []
      qvalues[q] << v
    end
  end
  order = qvalues.keys.sort.reverse
  order.inject([]) {|m, q| m.concat(qvalues[q].map {|v| [q, v] }) }
end

#to_s ⇒ Object

Returns a string representation of this header.



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# File 'lib/rack/accept/header.rb', line 140

def to_s
  [name, value].join(': ')
end

#value ⇒ Object

Returns the value of this header as a string.



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# File 'lib/rack/accept/header.rb', line 86

def value
  join(@qvalues)
end

#values ⇒ Object

Returns an array of all values of this header, in no particular order.



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# File 'lib/rack/accept/header.rb', line 91

def values
  @qvalues.keys
end