Chat Server in Erlang (13 May 2005)

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This is my first project in Erlang. I'm enjoying learning the language very much. It is well suited to programs that have many concurrent processes, like servers. Erlang was created by Ericsson. They did an excellent job in designing the language and platform.

This chat server is divided into nine modules:

chat contains code to start and stop the application
chat_acceptor accepts incoming tcp connections and creates liason processes to handle them
chat_acceptor_sup supervises the acceptor
chat_dispatcher keeps a list of active liasons and dispatches messages to them
chat_liason communicates with a client and sends messages to the dispatcher
chat_liason_sup supervises all of the liasons
chat_logger keeps a log file of chat server events and system errors
chat_report_handler plugs into the Erlang system logger and forwards error reports to chat_logger
chat_supervisor is the root of the application supervision tree. It supervises the logger, liason supervisor, dispatcher, and acceptor supervisor

The chat server is an Erlang OTP application. It is started with the command application:start(chat). Various server parameters are defined in the application definition file, ebin/chat.app. The logfile is created in the priv directory.

The protocol consists of lines of text terminated by CRLF. Here is the transcript of a telnet session:

Welcome to Unnamed Chat Server
1118308610 localhost:1273 connected.
Hello!
1118308613 <localhost:1273> Hello!
Goodbye...
1118308619 <localhost:1273> Goodbye...

Downloads

The files are provided for educational purposes only.

chat-0.1.tar.gz (11KB)
chat-0.1/ (browse the files online)

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