ferencd@0: require 'net/protocol'
ferencd@0: require 'parslet'
ferencd@0: 
ferencd@0: module Net
ferencd@0:   class HTTP < Protocol
ferencd@0:     module Server
ferencd@0:       #
ferencd@0:       # Inspired by:
ferencd@0:       #
ferencd@0:       # * [Thin](https://github.com/macournoyer/thin/blob/master/ext/thin_parser/common.rl)
ferencd@0:       # * [Unicorn](https://github.com/defunkt/unicorn/blob/master/ext/unicorn_http/unicorn_http_common.rl)
ferencd@0:       # * [RFC 2616](http://www.w3.org/Protocols/rfc2616/rfc2616.html)
ferencd@0:       #
ferencd@0:       class Parser < Parslet::Parser
ferencd@0: 
ferencd@0:         #
ferencd@0:         # Character Classes
ferencd@0:         #
ferencd@0:         rule(:digit) { match['0-9'] }
ferencd@0:         rule(:digits) { digit.repeat(1) }
ferencd@0:         rule(:xdigit) { digit | match['a-fA-F'] }
ferencd@0:         rule(:upper) { match['A-Z'] }
ferencd@0:         rule(:lower) { match['a-z'] }
ferencd@0:         rule(:alpha) { upper | lower }
ferencd@0:         rule(:alnum) { alpha | digit }
ferencd@0:         rule(:cntrl) { match['\x00-\x1f'] }
ferencd@0:         rule(:ascii) { match['\x00-\x7f'] }
ferencd@0: 
ferencd@0:         rule(:lws) { match[" \t"] }
ferencd@0:         rule(:crlf) { str("\r\n") }
ferencd@0: 
ferencd@0:         rule(:ctl) { cntrl | str("\x7f") }
ferencd@0:         rule(:text) { lws | (ctl.absnt? >> ascii) }
ferencd@0: 
ferencd@0:         rule(:safe) { charset('$', '-', '_', '.') }
ferencd@0:         rule(:extra) { charset('!', '*', "'", '(', ')', ',') }
ferencd@0:         rule(:reserved) { charset(';', '/', '?', ':', '@', '&', '=', '+') }
ferencd@0:         rule(:sorta_safe) { charset('"', '<', '>') }
ferencd@0: 
ferencd@0:         rule(:unsafe) { ctl | charset(' ', '#', '%') | sorta_safe }
ferencd@0:         rule(:national) {
ferencd@0:           (alpha | digit | reserved | extra | safe | unsafe).absnt? >> any
ferencd@0:         }
ferencd@0: 
ferencd@0:         rule(:unreserved) { alpha | digit | safe | extra | national }
ferencd@0:         rule(:uescape) { str("%u") >> xdigit >> xdigit >> xdigit >> xdigit }
ferencd@0:         rule(:escape) { str("%") >> xdigit >> xdigit }
ferencd@0:         rule(:uchar) { unreserved | uescape | escape | sorta_safe }
ferencd@0:         rule(:pchar) { uchar | charset(':', '@', '&', '=', '+') }
ferencd@0:         rule(:separators) {
ferencd@0:           lws | charset(
ferencd@0:             '(', ')', '<', '>', '@', ',', ';', ':', "\\", '"', '/', '[', ']',
ferencd@0:             '?', '=', '{', '}'
ferencd@0:           )
ferencd@0:         }
ferencd@0: 
ferencd@0:         #
ferencd@0:         # Elements
ferencd@0:         #
ferencd@0:         rule(:token) { (ctl | separators).absnt? >> ascii }
ferencd@0: 
ferencd@0:         rule(:comment_text) { (str('(') | str(')')).absnt? >> text }
ferencd@0:         rule(:comment) { str('(') >> comment_text.repeat >> str(')') }
ferencd@0: 
ferencd@0:         rule(:quoted_pair) { str("\\") >> ascii }
ferencd@0:         rule(:quoted_text) { quoted_pair | str('"').absnt? >> text }
ferencd@0:         rule(:quoted_string) { str('"') >> quoted_text >> str('"') }
ferencd@0: 
ferencd@0:         #
ferencd@0:         # URI Elements
ferencd@0:         #
ferencd@0:         rule(:scheme) {
ferencd@0:           (alpha | digit | charset('+', '-', '.')).repeat
ferencd@0:         }
ferencd@0:         rule(:host_name) {
ferencd@0:           (alnum | charset('-', '_', '.')).repeat(1)
ferencd@0:         }
ferencd@0:         rule(:user_info) {
ferencd@0:           (
ferencd@0:             unreserved | escape | charset(';', ':', '&', '=', '+')
ferencd@0:           ).repeat(1)
ferencd@0:         }
ferencd@0: 
ferencd@0:         rule(:path) { pchar.repeat(1) >> (str('/') >> pchar.repeat).repeat }
ferencd@0:         rule(:query_string) { (uchar | reserved).repeat }
ferencd@0:         rule(:param) { (pchar | str('/')).repeat }
ferencd@0:         rule(:params) { param >> (str(';') >> param).repeat }
ferencd@0:         rule(:frag) { (uchar | reserved).repeat }
ferencd@0: 
ferencd@0:         rule(:uri_path) {
ferencd@0:           (str('/').maybe >> path.maybe).as(:path) >>
ferencd@0:           (str(';') >> params.as(:params)).maybe >>
ferencd@0:           (str('?') >> query_string.as(:query)).maybe >>
ferencd@0:           (str('#') >> frag.as(:fragment)).maybe
ferencd@0:         }
ferencd@0: 
ferencd@0:         rule(:uri) {
ferencd@0:           scheme.as(:scheme) >> str(':') >> str('//').maybe >>
ferencd@0:           (user_info.as(:user_info) >> str('@')).maybe >>
ferencd@0:           host_name.as(:host) >>
ferencd@0:           (str(':') >> digits.as(:port)).maybe >>
ferencd@0:           uri_path
ferencd@0:         }
ferencd@0: 
ferencd@0:         rule(:request_uri) { str('*') | uri | uri_path }
ferencd@0: 
ferencd@0:         #
ferencd@0:         # HTTP Elements
ferencd@0:         #
ferencd@0:         rule(:request_method) { upper.repeat(1,20) | token.repeat(1) }
ferencd@0: 
ferencd@0:         rule(:version_number) { digits >> str('.') >> digits }
ferencd@0:         rule(:http_version) { str('HTTP/') >> version_number.as(:version) }
ferencd@0:         rule(:request_line) {
ferencd@0:           request_method.as(:method) >> str(' ') >>
ferencd@0:           request_uri.as(:uri) >> str(' ') >>
ferencd@0:           http_version
ferencd@0:         }
ferencd@0: 
ferencd@0:         rule(:header_name) { (str(':').absnt? >> token).repeat(1) }
ferencd@0:         rule(:header_value) {
ferencd@0:           (text | token | separators | quoted_string).repeat(1)
ferencd@0:         }
ferencd@0: 
ferencd@0:         rule(:header) {
ferencd@0:           header_name.as(:name) >> str(':') >> lws.repeat(1) >>
ferencd@0:           header_value.as(:value) >> crlf
ferencd@0:         }
ferencd@0:         rule(:request) {
ferencd@0:           request_line >> crlf >>
ferencd@0:           header.repeat.as(:headers) >> crlf
ferencd@0:         }
ferencd@0: 
ferencd@0:         root :request
ferencd@0: 
ferencd@0:         protected
ferencd@0: 
ferencd@0:         #
ferencd@0:         # Creates a matcher for the given characters.
ferencd@0:         #
ferencd@0:         # @param [Array<String>] chars
ferencd@0:         #   The characters to match.
ferencd@0:         #
ferencd@0:         def charset(*chars)
ferencd@0:           match[chars.map { |c| Regexp.escape(c) }.join]
ferencd@0:         end
ferencd@0: 
ferencd@0:       end
ferencd@0:     end
ferencd@0:   end
ferencd@0: end