forked from igrigorik/em-websocket
/
handler_factory.rb
107 lines (95 loc) · 3.6 KB
/
handler_factory.rb
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module EventMachine
module WebSocket
class HandlerFactory
PATH = /^(\w+) (\/[^\s]*) HTTP\/1\.1$/
HEADER = /^([^:]+):\s*(.+)$/
def self.build(connection, data, secure = false, debug = false)
(header, remains) = data.split("\r\n\r\n", 2)
unless remains
# The whole header has not been received yet.
return nil
end
request = {}
lines = header.split("\r\n")
# extract request path
first_line = lines.shift.match(PATH)
raise HandshakeError, "Invalid HTTP header" unless first_line
request['method'] = first_line[1].strip
request['path'] = first_line[2].strip
unless request["method"] == "GET"
raise HandshakeError, "Must be GET request"
end
# extract query string values
request['query'] = Addressable::URI.parse(request['path']).query_values ||= {}
# extract remaining headers
lines.each do |line|
h = HEADER.match(line)
request[h[1].strip.downcase] = h[2].strip if h
end
build_with_request(connection, request, remains, secure, debug)
end
def self.build_with_request(connection, request, remains, secure = false, debug = false)
# Determine version heuristically
version = if request['sec-websocket-version']
# Used from drafts 04 onwards
request['sec-websocket-version'].to_i
elsif request['sec-websocket-draft']
# Used in drafts 01 - 03
request['sec-websocket-draft'].to_i
elsif request['sec-websocket-key1']
76
else
75
end
# Additional handling of bytes after the header if required
case version
when 75
if !remains.empty?
raise HandshakeError, "Extra bytes after header"
end
when 76, 1..3
if remains.length < 8
# The whole third-key has not been received yet.
return nil
elsif remains.length > 8
raise HandshakeError, "Extra bytes after third key"
end
request['third-key'] = remains
end
# Validate that Connection and Upgrade headers
unless request['connection'] && request['connection'] =~ /Upgrade/ && request['upgrade'] && request['upgrade'].downcase == 'websocket'
raise HandshakeError, "Connection and Upgrade headers required"
end
# transform headers
protocol = (secure ? "wss" : "ws")
request['host'] = Addressable::URI.parse("#{protocol}://"+request['host'])
case version
when 75
Handler75.new(connection, request, debug)
when 76
Handler76.new(connection, request, debug)
when 1..3
# We'll use handler03 - I believe they're all compatible
Handler03.new(connection, request, debug)
when 5
Handler05.new(connection, request, debug)
when 6
Handler06.new(connection, request, debug)
when 7
Handler07.new(connection, request, debug)
when 8
# drafts 9, 10, 11 and 12 should never change the version
# number as they are all the same as version 08.
Handler08.new(connection, request, debug)
when 13
# drafts 13 to 17 all identify as version 13 as they are
# only minor changes or text changes.
Handler13.new(connection, request, debug)
else
# According to spec should abort the connection
raise WebSocketError, "Protocol version #{version} not supported"
end
end
end
end
end