A Multipurpose Server
Once we remove the idea that individual services need to have their different message formats, we can use uniform messaging to solve a range of problems. Here, for example, is a “multiserver”:
| multi_server.erl | |
| Line 1 | -module(multi_server). |
| - | -export([start/0]). |
| - | |
| - | start() -> spawn(fun() -> multi_server() end). |
| 5 | |
| - | multi_server() -> |
| - | receive |
| - | {_Pid, {email, _From, _Subject, _Text} = Email} -> |
| - | {ok, S} = file:open("mbox", [write,append]), |
| 10 | io:format(S, "~p.~n", [Email]), |
| - | file:close(S); |
| - | {_Pid, {im, From, Text}} -> |
| - | io:format("Msg (~s): ~s~n",[From, Text]); |
| - | {Pid, {get, File}} -> |
| 15 | Pid ! {self(), file:read_file(File)}; |
| - | Any -> |
| - | io:format("multi server got:~p~n",[Any]) ... |
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