debian-mirror-gitlab/debian/gems-compat/actionpack-5.1.6.1/lib/action_dispatch/http/headers.rb

130 lines
3.6 KiB
Ruby

module ActionDispatch
module Http
# Provides access to the request's HTTP headers from the environment.
#
# env = { "CONTENT_TYPE" => "text/plain", "HTTP_USER_AGENT" => "curl/7.43.0" }
# headers = ActionDispatch::Http::Headers.from_hash(env)
# headers["Content-Type"] # => "text/plain"
# headers["User-Agent"] # => "curl/7.43.0"
#
# Also note that when headers are mapped to CGI-like variables by the Rack
# server, both dashes and underscores are converted to underscores. This
# ambiguity cannot be resolved at this stage anymore. Both underscores and
# dashes have to be interpreted as if they were originally sent as dashes.
#
# # GET / HTTP/1.1
# # ...
# # User-Agent: curl/7.43.0
# # X_Custom_Header: token
#
# headers["X_Custom_Header"] # => nil
# headers["X-Custom-Header"] # => "token"
class Headers
CGI_VARIABLES = Set.new(%W[
AUTH_TYPE
CONTENT_LENGTH
CONTENT_TYPE
GATEWAY_INTERFACE
HTTPS
PATH_INFO
PATH_TRANSLATED
QUERY_STRING
REMOTE_ADDR
REMOTE_HOST
REMOTE_IDENT
REMOTE_USER
REQUEST_METHOD
SCRIPT_NAME
SERVER_NAME
SERVER_PORT
SERVER_PROTOCOL
SERVER_SOFTWARE
]).freeze
HTTP_HEADER = /\A[A-Za-z0-9-]+\z/
include Enumerable
def self.from_hash(hash)
new ActionDispatch::Request.new hash
end
def initialize(request) # :nodoc:
@req = request
end
# Returns the value for the given key mapped to @env.
def [](key)
@req.get_header env_name(key)
end
# Sets the given value for the key mapped to @env.
def []=(key, value)
@req.set_header env_name(key), value
end
# Add a value to a multivalued header like Vary or Accept-Encoding.
def add(key, value)
@req.add_header env_name(key), value
end
def key?(key)
@req.has_header? env_name(key)
end
alias :include? :key?
DEFAULT = Object.new # :nodoc:
# Returns the value for the given key mapped to @env.
#
# If the key is not found and an optional code block is not provided,
# raises a <tt>KeyError</tt> exception.
#
# If the code block is provided, then it will be run and
# its result returned.
def fetch(key, default = DEFAULT)
@req.fetch_header(env_name(key)) do
return default unless default == DEFAULT
return yield if block_given?
raise KeyError, key
end
end
def each(&block)
@req.each_header(&block)
end
# Returns a new Http::Headers instance containing the contents of
# <tt>headers_or_env</tt> and the original instance.
def merge(headers_or_env)
headers = @req.dup.headers
headers.merge!(headers_or_env)
headers
end
# Adds the contents of <tt>headers_or_env</tt> to original instance
# entries; duplicate keys are overwritten with the values from
# <tt>headers_or_env</tt>.
def merge!(headers_or_env)
headers_or_env.each do |key, value|
@req.set_header env_name(key), value
end
end
def env; @req.env.dup; end
private
# Converts an HTTP header name to an environment variable name if it is
# not contained within the headers hash.
def env_name(key)
key = key.to_s
if key =~ HTTP_HEADER
key = key.upcase.tr("-", "_")
key = "HTTP_" + key unless CGI_VARIABLES.include?(key)
end
key
end
end
end
end