Class: Protocol::HTTP::Headers

Inherits:
Object
  • Object
show all
Defined in:
lib/protocol/http/headers.rb

Overview

Headers are an array of key-value pairs. Some header keys represent multiple values.

Defined Under Namespace

Classes: Merged, Multiple, Split

Constant Summary collapse

MERGE_POLICY = 
{
	# Headers which may only be specified once.
	'content-type' => false,
	'content-disposition' => false,
	'content-length' => false,
	'user-agent' => false,
	'referer' => false,
	'host' => false,
	'authorization' => false,
	'proxy-authorization' => false,
	'if-modified-since' => false,
	'if-unmodified-since' => false,
	'from' => false,
	'location' => false,
	'max-forwards' => false,
	
	'connection' => Split,
	
	# Headers specifically for proxies:
	'via' => Split,
	'x-forwarded-for' => Split,
	
	# Headers which may be specified multiple times, but which can't be concatenated.
	'set-cookie' => Multiple,
	'www-authenticate' => Multiple,
	'proxy-authenticate' => Multiple
}.tap{|hash| hash.default = Split}

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(fields = nil, indexed = nil) ⇒ Headers

Returns a new instance of Headers.



61
62
63
64
65
66
67
68
69
70
71
72
73
 
# File 'lib/protocol/http/headers.rb', line 61

def initialize(fields = nil, indexed = nil)
	if fields
		@fields = fields.dup
	else
		@fields = []
	end
	
	if indexed
		@indexed = indexed.dup
	else
		@indexed = nil
	end
end

Instance Attribute Details

#fields ⇒ Object (readonly)

An array of ‘[key, value]` pairs.



85
86
87
 
# File 'lib/protocol/http/headers.rb', line 85

def fields
  @fields
end

Class Method Details

.[](hash) ⇒ Object 



57
58
59
 
# File 'lib/protocol/http/headers.rb', line 57

def self.[] hash
	self.new(hash.to_a)
end

Instance Method Details

#==(other) ⇒ Object 



238
239
240
241
242
243
244
245
246
247
 
# File 'lib/protocol/http/headers.rb', line 238

def == other
	case other
	when Hash
		to_h == other
	when Headers
		@fields == other.fields
	else
		@fields == other
	end
end

#[](key) ⇒ Object 



221
222
223
 
# File 'lib/protocol/http/headers.rb', line 221

def [] key
	to_h[key]
end

#[]=(key, value) ⇒ Object

Append the value to the given key. Some values can be appended multiple times, others can only be set once.

Parameters:

  • key (String) —

    The header key.

  • value —

    The header value.



147
148
149
150
151
152
153
 
# File 'lib/protocol/http/headers.rb', line 147

def []= key, value
	if @indexed
		merge_into(@indexed, key.downcase, value)
	end
	
	@fields << [key, value]
end

#add(key, value) ⇒ Object 



128
129
130
 
# File 'lib/protocol/http/headers.rb', line 128

def add(key, value)
	self[key] = value
end

#clear ⇒ Object 



79
80
81
82
 
# File 'lib/protocol/http/headers.rb', line 79

def clear
	@fields.clear
	@indexed = nil
end

#delete(key) ⇒ Object

Delete all headers with the given key, and return the merged value.



184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
 
# File 'lib/protocol/http/headers.rb', line 184

def delete(key)
	deleted, @fields = @fields.partition do |field|
		field.first.downcase == key
	end
	
	if deleted.empty?
		return nil
	end
	
	if @indexed
		return @indexed.delete(key)
	elsif policy = MERGE_POLICY[key]
		(key, value), *tail = deleted
		merged = policy.new(value)
		
		tail.each{|k,v| merged << v}
		
		return merged
	else
		key, value = deleted.last
		return value
	end
end

#dup ⇒ Object 



75
76
77
 
# File 'lib/protocol/http/headers.rb', line 75

def dup
	self.class.new(@fields, @indexed)
end

#each(&block) ⇒ Object 



103
104
105
 
# File 'lib/protocol/http/headers.rb', line 103

def each(&block)
	@fields.each(&block)
end

#empty? ⇒ Boolean

Returns:

  • (Boolean) 


99
100
101
 
# File 'lib/protocol/http/headers.rb', line 99

def empty?
	@fields.empty?
end

#extract(keys) ⇒ Object Also known as: slice! 



111
112
113
114
115
116
117
118
119
120
121
122
123
 
# File 'lib/protocol/http/headers.rb', line 111

def extract(keys)
	deleted, @fields = @fields.partition do |field|
		keys.include?(field.first.downcase)
	end
	
	if @indexed
		keys.each do |key|
			@indexed.delete(key)
		end
	end
	
	return deleted
end

#freeze ⇒ Object 



87
88
89
90
91
92
93
94
95
96
97
 
# File 'lib/protocol/http/headers.rb', line 87

def freeze
	return if frozen?
	
	# Ensure @indexed is generated:
	self.to_h
	
	@fields.freeze
	@indexed.freeze
	
	super
end

#include?(key) ⇒ Boolean

Returns:

  • (Boolean) 


107
108
109
 
# File 'lib/protocol/http/headers.rb', line 107

def include? key
	self[key] != nil
end

#inspect ⇒ Object 



234
235
236
 
# File 'lib/protocol/http/headers.rb', line 234

def inspect
	"#<#{self.class} #{@fields.inspect}>"
end

#merge(headers) ⇒ Object 



140
141
142
 
# File 'lib/protocol/http/headers.rb', line 140

def merge(headers)
	self.dup.merge!(headers)
end

#merge!(headers) ⇒ Object 



132
133
134
135
136
137
138
 
# File 'lib/protocol/http/headers.rb', line 132

def merge!(headers)
	headers.each do |key, value|
		self[key] = value
	end
	
	return self
end

#to_h ⇒ Object

A hash table of ‘policy.map(values)`



226
227
228
229
230
231
232
 
# File 'lib/protocol/http/headers.rb', line 226

def to_h
	@indexed ||= @fields.inject({}) do |hash, (key, value)|
		merge_into(hash, key.downcase, value)
		
		hash
	end
end