@@ -1,3 +1,8 @@ += + * Major changes + * Remove dependency on Erlectricity + * Simplify processing loop + = 1.0.0 / 2009-10-19 * No Changes. Production ready! History.txt @@ -11,8 +11,7 @@ begin gem.authors = ["Tom Preston-Werner"] gem.files.include(["ext"]) gem.extensions << 'ext/extconf.rb' - gem.add_dependency('erlectricity', '>= 1.1.0') - gem.add_dependency('bert', '>= 1.0.0') + gem.add_dependency('bert', '>= 1.1.0') gem.add_dependency('bertrpc', '>= 1.0.0') # gem is a Gem::Specification... see http://www.rubygems.org/read/chapter/20 for additional settings Rakefile @@ -14,6 +14,10 @@ mod(:slowcalc) do sleep(rand * 2) a + b end + + fun(:superslow) do + sleep 10 + end end # Throw an error examples/calc.rb @@ -11,6 +11,11 @@ class Ernie self.current_mod = nil self.logger = nil + # Record a module. + # +name+ is the module Symbol + # +block+ is the Block containing function definitions + # + # Returns nothing def self.mod(name, block) m = Mod.new(name) self.current_mod = m @@ -18,69 +23,129 @@ class Ernie block.call end + # Record a function. + # +name+ is the function Symbol + # +block+ is the Block to associate + # + # Returns nothing def self.fun(name, block) self.current_mod.fun(name, block) end + # Set the logfile to given path. + # +file+ is the String path to the logfile + # + # Returns nothing def self.logfile(file) self.logger = Logger.new(file) end + # If logging is enabled, log the given text. + # +text+ is the String to log + # + # Returns nothing def self.log(text) self.logger.info(text) if self.logger end + # Dispatch the request to the proper mod:fun. + # +mod+ is the module Symbol + # +fun+ is the function Symbol + # +args+ is the Array of arguments + # + # Returns the Ruby object response def self.dispatch(mod, fun, args) - xargs = BERT::Decoder.convert(args) - self.log("-- " + [mod, fun, xargs].inspect) self.mods[mod] || raise(ServerError.new("No such module '#{mod}'")) self.mods[mod].funs[fun] || raise(ServerError.new("No such function '#{mod}:#{fun}'")) - res = self.mods[mod].funs[fun].call(*xargs) - BERT::Encoder.convert(res) + self.mods[mod].funs[fun].call(*args) end + # Read the length header from the wire. + # +input+ is the IO from which to read + # + # Returns the size Integer if one was read + # Returns nil otherwise + def self.read_4(input) + raw = input.read(4) + return nil unless raw + raw.unpack('N').first + end + + # Read a BERP from the wire and decode it to a Ruby object. + # +input+ is the IO from which to read + # + # Returns a Ruby object if one could be read + # Returns nil otherwise + def self.read_berp(input) + packet_size = self.read_4(input) + return nil unless packet_size + bert = input.read(packet_size) + BERT.decode(bert) + end + + # Write the given Ruby object to the wire as a BERP. + # +output+ is the IO on which to write + # +ruby+ is the Ruby object to encode + # + # Returns nothing + def self.write_berp(output, ruby) + data = BERT.encode(ruby) + output.write([data.length].pack("N")) + output.write(data) + end + + # Start the processing loop. + # + # Loops forever def self.start self.log("Starting") self.log(self.mods.inspect) - receive do |f| - f.when([:call, Symbol, Symbol, Array]) do |mod, fun, args| - self.log("-> " + [:call, mod, fun, args].inspect) + + input = IO.new(3) + output = IO.new(4) + input.sync = true + output.sync = true + + loop do + iruby = self.read_berp(input) + unless iruby + puts "Could not read BERP length header. Ernie server may have gone away. Exiting now." + exit! + end + + if iruby.size == 4 && iruby[0] == :call + mod, fun, args = iruby[1..3] + self.log("-> " + iruby.inspect) begin res = self.dispatch(mod, fun, args) - xres = [:reply, res] - self.log("<- " + xres.inspect) - f.send!(xres) + oruby = t[:reply, res] + self.log("<- " + oruby.inspect) + write_berp(output, oruby) rescue ServerError => e - xres = [:error, [:server, 0, e.class.to_s, e.message, e.backtrace]] - self.log("<- " + xres.inspect) + oruby = t[:error, t[:server, 0, e.class.to_s, e.message, e.backtrace]] + self.log("<- " + oruby.inspect) self.log(e.backtrace.join("\n")) - f.send!(xres) + write_berp(output, oruby) rescue Object => e - xres = [:error, [:user, 0, e.class.to_s, e.message, e.backtrace]] - self.log("<- " + xres.inspect) + oruby = t[:error, t[:user, 0, e.class.to_s, e.message, e.backtrace]] + self.log("<- " + oruby.inspect) self.log(e.backtrace.join("\n")) - f.send!(xres) + write_berp(output, oruby) end - f.receive_loop - end - - f.when([:cast, Symbol, Symbol, Array]) do |mod, fun, args| + elsif iruby.size == 4 && iruby[0] == :cast + mod, fun, args = iruby[1..3] self.log("-> " + [:cast, mod, fun, args].inspect) begin self.dispatch(mod, fun, args) rescue Object => e # ignore end - f.send!([:noreply]) - f.receive_loop - end - - f.when(Any) do |any| - self.log("-> " + any.inspect) - xres = [:error, [:server, 0, "Invalid request: #{any.inspect}"]] - self.log("<- " + xres.inspect) - f.send!(xres) - f.receive_loop + write_berp(output, t[:noreply]) + else + self.log("-> " + iruby.inspect) + oruby = t[:error, t[:server, 0, "Invalid request: #{iruby.inspect}"]] + self.log("<- " + oruby.inspect) + write_berp(output, oruby) end end end lib/ernie.rb bf7e17b1c26b1be768648575aa3339c72c7906f9 Tom Preston-Werner tom@mojombo.com http://github.com/mojombo/ernie/commit/d581d0c4ddd97c07696b64b32cf5b355c50af42f d581d0c4ddd97c07696b64b32cf5b355c50af42f 2009-10-28T17:08:05-07:00 2009-10-28T15:34:59-07:00 remove dependency on erlectricity 6ca7dff3f32af1bfcaac3e5c7b2f381af24adcb9 Tom Preston-Werner tom@mojombo.com