Class: Rack::Response
Overview
Rack::Response provides a convenient interface to create a Rack response.
It allows setting of headers and cookies, and provides useful defaults (an OK response with empty headers and body).
You can use Response#write to iteratively generate your response, but note that this is buffered by Rack::Response until you call finish
. finish
however can take a block inside which calls to write
are synchronous with the Rack response.
Your application’s call
should end returning Response#finish.
Direct Known Subclasses
Defined Under Namespace
Constant Summary collapse
- CHUNKED =
'chunked'
- STATUS_WITH_NO_ENTITY_BODY =
Utils::STATUS_WITH_NO_ENTITY_BODY
Instance Attribute Summary collapse
-
#body ⇒ Object
Returns the value of attribute body.
-
#headers ⇒ Object
readonly
Returns the value of attribute headers.
-
#length ⇒ Object
Returns the value of attribute length.
-
#status ⇒ Object
Returns the value of attribute status.
Class Method Summary collapse
Instance Method Summary collapse
- #chunked? ⇒ Boolean
- #close ⇒ Object
- #delete_header(key) ⇒ Object
- #each(&callback) ⇒ Object
- #empty? ⇒ Boolean
-
#finish(&block) ⇒ Array
(also: #to_a)
Generate a response array consistent with the requirements of the SPEC.
- #get_header(key) ⇒ Object (also: #[])
- #has_header?(key) ⇒ Boolean
-
#initialize(body = nil, status = 200, headers = {}) {|_self| ... } ⇒ Response
constructor
Initialize the response object with the specified
body
,status
andheaders
. - #no_entity_body? ⇒ Boolean
- #redirect(target, status = 302) ⇒ Object
- #set_header(key, value) ⇒ Object (also: #[]=)
-
#write(chunk) ⇒ Object
Append to body and update content-length.
Methods included from Helpers
#accepted?, #add_header, #bad_request?, #cache!, #cache_control, #cache_control=, #client_error?, #content_length, #content_type, #content_type=, #created?, #delete_cookie, #do_not_cache!, #etag, #etag=, #forbidden?, #include?, #informational?, #invalid?, #location, #location=, #media_type, #media_type_params, #method_not_allowed?, #moved_permanently?, #no_content?, #not_acceptable?, #not_found?, #ok?, #precondition_failed?, #redirect?, #redirection?, #request_timeout?, #server_error?, #set_cookie, #set_cookie_header, #set_cookie_header=, #successful?, #unauthorized?, #unprocessable?
Constructor Details
#initialize(body = nil, status = 200, headers = {}) {|_self| ... } ⇒ Response
Initialize the response object with the specified body
, status
and headers
.
If the body
is nil
, construct an empty response object with internal buffering.
If the body
responds to to_str
, assume it’s a string-like object and construct a buffered response object containing using that string as the initial contents of the buffer.
Otherwise it is expected body
conforms to the normal requirements of a Rack response body, typically implementing one of each
(enumerable body) or call
(streaming body).
The status
defaults to 200
which is the “OK” HTTP status code. You can provide any other valid status code.
The headers
must be a Hash
of key-value header pairs which conform to the Rack specification for response headers. The key must be a String
instance and the value can be either a String
or Array
instance.
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# File 'lib/rack/response.rb', line 54 def initialize(body = nil, status = 200, headers = {}) @status = status.to_i unless headers.is_a?(Hash) raise ArgumentError, "Headers must be a Hash!" end @headers = Headers.new # Convert headers input to a plain hash with lowercase keys. headers.each do |k, v| @headers[k] = v end @writer = self.method(:append) @block = nil # Keep track of whether we have expanded the user supplied body. if body.nil? @body = [] @buffered = true @length = 0 elsif body.respond_to?(:to_str) @body = [body] @buffered = true @length = body.to_str.bytesize else @body = body @buffered = nil # undetermined as of yet. @length = 0 end yield self if block_given? end |
Instance Attribute Details
#body ⇒ Object
Returns the value of attribute body.
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# File 'lib/rack/response.rb', line 31 def body @body end |
#headers ⇒ Object (readonly)
Returns the value of attribute headers.
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# File 'lib/rack/response.rb', line 32 def headers @headers end |
#length ⇒ Object
Returns the value of attribute length.
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# File 'lib/rack/response.rb', line 31 def length @length end |
#status ⇒ Object
Returns the value of attribute status.
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# File 'lib/rack/response.rb', line 31 def status @status end |
Class Method Details
.[](status, headers, body) ⇒ Object
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# File 'lib/rack/response.rb', line 24 def self.[](status, headers, body) self.new(body, status, headers) end |
Instance Method Details
#chunked? ⇒ Boolean
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# File 'lib/rack/response.rb', line 94 def chunked? CHUNKED == get_header(TRANSFER_ENCODING) end |
#close ⇒ Object
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# File 'lib/rack/response.rb', line 148 def close @body.close if @body.respond_to?(:close) end |
#delete_header(key) ⇒ Object
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# File 'lib/rack/response.rb', line 168 def delete_header(key) raise ArgumentError unless key.is_a?(String) @headers.delete key end |
#each(&callback) ⇒ Object
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# File 'lib/rack/response.rb', line 128 def each(&callback) @body.each(&callback) @buffered = true if @block @writer = callback @block.call(self) end end |
#empty? ⇒ Boolean
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# File 'lib/rack/response.rb', line 152 def empty? @block == nil && @body.empty? end |
#finish(&block) ⇒ Array Also known as: to_a
Generate a response array consistent with the requirements of the SPEC. which is suitable to be returned from the middleware ‘#call(env)` method.
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# File 'lib/rack/response.rb', line 106 def finish(&block) if no_entity_body? delete_header CONTENT_TYPE delete_header CONTENT_LENGTH close return [@status, @headers, []] else if @length && @length > 0 && !chunked? set_header CONTENT_LENGTH, @length.to_s end if block_given? @block = block return [@status, @headers, self] else return [@status, @headers, @body] end end end |
#get_header(key) ⇒ Object Also known as: []
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# File 'lib/rack/response.rb', line 160 def get_header(key) raise ArgumentError unless key.is_a?(String) @headers[key] end |
#has_header?(key) ⇒ Boolean
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# File 'lib/rack/response.rb', line 156 def has_header?(key) raise ArgumentError unless key.is_a?(String) @headers.key?(key) end |
#no_entity_body? ⇒ Boolean
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# File 'lib/rack/response.rb', line 98 def no_entity_body? # The response body is an enumerable body and it is not allowed to have an entity body. @body.respond_to?(:each) && STATUS_WITH_NO_ENTITY_BODY[@status] end |
#redirect(target, status = 302) ⇒ Object
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# File 'lib/rack/response.rb', line 89 def redirect(target, status = 302) self.status = status self.location = target end |
#set_header(key, value) ⇒ Object Also known as: []=
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# File 'lib/rack/response.rb', line 164 def set_header(key, value) raise ArgumentError unless key.is_a?(String) @headers[key] = value end |
#write(chunk) ⇒ Object
Append to body and update content-length.
NOTE: Do not mix #write and direct #body access!
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# File 'lib/rack/response.rb', line 142 def write(chunk) buffered_body! @writer.call(chunk.to_s) end |