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

Constant Summary collapse

Split = 
Header::Split
Multiple = 
Header::Multiple
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' => Header::Connection,
	'cache-control' => Header::CacheControl,
	
	# Headers specifically for proxies:
	'via' => Split,
	'x-forwarded-for' => Split,
	
	# Headers which may be specified multiple times, but which can't be concatenated:
	'www-authenticate' => Multiple,
	'proxy-authenticate' => Multiple,
	
	# Custom headers:
	'set-cookie' => Header::SetCookie,
	'cookie' => Header::Cookie,
}.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.



40
41
42
43
44
45
46
47
48
49
50
51
52
 
# File 'lib/protocol/http/headers.rb', line 40

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.



64
65
66
 
# File 'lib/protocol/http/headers.rb', line 64

def fields
  @fields
end

Class Method Details

.[](hash) ⇒ Object 



36
37
38
 
# File 'lib/protocol/http/headers.rb', line 36

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

Instance Method Details

#==(other) ⇒ Object 



221
222
223
224
225
226
227
228
229
230
 
# File 'lib/protocol/http/headers.rb', line 221

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

#[](key) ⇒ Object 



204
205
206
 
# File 'lib/protocol/http/headers.rb', line 204

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.



126
127
128
129
130
131
132
 
# File 'lib/protocol/http/headers.rb', line 126

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

#add(key, value) ⇒ Object 



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

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

#clear ⇒ Object 



58
59
60
61
 
# File 'lib/protocol/http/headers.rb', line 58

def clear
	@fields.clear
	@indexed = nil
end

#delete(key) ⇒ Object

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



167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
 
# File 'lib/protocol/http/headers.rb', line 167

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 



54
55
56
 
# File 'lib/protocol/http/headers.rb', line 54

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

#each(&block) ⇒ Object 



82
83
84
 
# File 'lib/protocol/http/headers.rb', line 82

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

#empty? ⇒ Boolean

Returns:

  • (Boolean) 


78
79
80
 
# File 'lib/protocol/http/headers.rb', line 78

def empty?
	@fields.empty?
end

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



90
91
92
93
94
95
96
97
98
99
100
101
102
 
# File 'lib/protocol/http/headers.rb', line 90

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 



66
67
68
69
70
71
72
73
74
75
76
 
# File 'lib/protocol/http/headers.rb', line 66

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

#include?(key) ⇒ Boolean

Returns:

  • (Boolean) 


86
87
88
 
# File 'lib/protocol/http/headers.rb', line 86

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

#inspect ⇒ Object 



217
218
219
 
# File 'lib/protocol/http/headers.rb', line 217

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

#merge(headers) ⇒ Object 



119
120
121
 
# File 'lib/protocol/http/headers.rb', line 119

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

#merge!(headers) ⇒ Object 



111
112
113
114
115
116
117
 
# File 'lib/protocol/http/headers.rb', line 111

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)`



209
210
211
212
213
214
215
 
# File 'lib/protocol/http/headers.rb', line 209

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