julienxx/chitchat

Erlang Chat app

chitchat

Erlang Chat app

Send a message from the router to the router:

P = message_router:start().
P ! {send_chat_msg, P, "Hello!"}.

Send a message from a client to the router:

chat_client:send_message(P, "Hello from client").

Send a message from a client to another router:

P1 = chat_client:start_router().
chat_client:send_message(P1, "Hello from client to router #1").

Stop message router:

message_router:stop(P).

Conversation:

P1 = chat_client:start_router().
  <0.136.0>
P2 = chat_client:start_router().
  <0.138.0>
chat_client:send_message(P2, "Hello P2!").
  Received "Hello P2!"
  {send_chat_msg,<0.138.0>,"Hello P2!"}
chat_client:send_message(P1, "How are you P1?").
  Received "How are you P1?"
  {send_chat_msg,<0.136.0>,"How are you P1?"}
message_router:stop(P1).
  Shutting down
  shutdown
message_router:stop(P2).
  Shutting down
  shutdown

Nickname registration:

chat_client:start_router().
  true
chat_client:register_nickname("Alice").
  {register_nick,"Alice",#Fun<chat_client.0.124345407>}
chat_client:send_message("Alice", "Hello Alice").
  "Alice" received: "Hello Alice"
  {send_chat_msg,"Alice","Hello Alice"}
chat_client:send_message("Alice", "Bye Alice").
  "Alice" received: "Bye Alice"
  {send_chat_msg,"Alice","Bye Alice"}
chat_client:unregister_nickname("Alice").
  {unregister_nick,"Alice"}
chat_client:send_message("Alice", "Bye Alice").
  Unknown client
  {send_chat_msg,"Alice","Bye Alice"}

Multi-node chat:

• Start two different nodes:

erl -sname node1 -setcookie chitchat

erl -sname node2 -setcookie chitchat

• let's test if the nodes see each other:

(node1@imac-de-julien)1> net_adm:ping('node2@imac-de-julien').
  pong

(node2@imac-de-julien)1> net_adm:ping('node1@imac-de-julien').
  pong

• node1 will be the message router:

(node1@imac-de-julien)3> chat_client:start_router().
  yes

• node2 can see the registered message_router:

(node2@imac-de-julien)2> global:registered_names().
  [message_router]

• register a nickname 'Alice' on node1:

(node1@imac-de-julien)4> chat_client:register_nickname("Alice").
  <0.49.0>

• register a nickname 'Bob' on node2:

(node2@imac-de-julien)4> chat_client:register_nickname("Bob").
  <5898.49.0>

• Alice sends a message to Bob:

(node1@imac-de-julien)5> chat_client:send_message("Bob", "Hi Bob!").
  <0.49.0>

• On Bob's side:

"Bob" received: "Hi Bob!"

• Bob replies:

(node2@imac-de-julien)4> chat_client:send_message("Alice", "How R U Alice?").
  <5898.49.0>

• On Alice's side:

"Alice" received: "How R U Alice?"

• Now test unregistering Alice:

(node1@imac-de-julien)7> chat_client:unregister_nickname("Alice").
  <0.49.0>

• Bob tries to send a message to Alice again:

(node2@imac-de-julien)5> chat_client:send_message("Alice", "U there?").
  <5898.49.0>

• On node1 (the message router):

Error: Unknown client: "Alice"