elephant v0.2.11 Elephant View Source
Elephant: A STOMP client.
Use Elephant as the primary API and Elephant.Message for working with received messages.
Example
{:ok, pid} = Elephant.start_link
Elephant.connect(pid, {127,0,0,1}, 61613, "admin", "admin")
callback = fn m -> IO.puts(inspect(m)) end
Elephant.subscribe(pid, "foo.bar", callback)
Elephant.disconnect(pid)For more control, use pattern matching in the callback:
callback = fn
%Elephant.Message{command: :message, headers: headers, body: body} ->
Logger.info(["Received MESSAGE", "\nheaders: ", inspect(headers), "\nbody: ", inspect(body)])
%Elephant.Message{command: :error, headers: headers, body: body} ->
Logger.error(["Received ERROR", "\nheaders: ", inspect(headers), "\nbody: ", inspect(body)])
%Elephant.Message{command: cmd, headers: headers, body: body} ->
Logger.error([
"Received unknown command: ", cmd,
"\nheaders: ",
inspect(headers),
"\nbody: ",
inspect(body)
])
endStarting in a supervision tree
children = [
worker(Elephant, [%{}, [name: Elephant]])
]Link to this section Summary
Functions
Returns a specification to start this module under a supervisor
Connect to server
Disconnect from server
Disconnects from server
Invoked when the server is started. start_link/3 or start/3 will
block until it returns
Receive messages from the TCP socket
Subscribe to a queue and register a callback for received messages
Unsubscribe from a queue
Link to this section Functions
Returns a specification to start this module under a supervisor.
See Supervisor.
Connect to server.
host must be inet:socket_address() | inet:hostname(), for example {127,0,0,1}.
Disconnect from server.
Disconnects from server.
Returns {:ok, :disconnected} or {:error, :disconnect_failed, message}.
Invoked when the server is started. start_link/3 or start/3 will
block until it returns.
init_arg is the argument term (second argument) passed to start_link/3.
Returning {:ok, state} will cause start_link/3 to return
{:ok, pid} and the process to enter its loop.
Returning {:ok, state, timeout} is similar to {:ok, state}
except handle_info(:timeout, state) will be called after timeout
milliseconds if no messages are received within the timeout.
Returning {:ok, state, :hibernate} is similar to {:ok, state}
except the process is hibernated before entering the loop. See
c:handle_call/3 for more information on hibernation.
Returning {:ok, state, {:continue, continue}} is similar to
{:ok, state} except that immediately after entering the loop
the c:handle_continue/2 callback will be invoked with the value
continue as first argument.
Returning :ignore will cause start_link/3 to return :ignore and
the process will exit normally without entering the loop or calling
c:terminate/2. If used when part of a supervision tree the parent
supervisor will not fail to start nor immediately try to restart the
GenServer. The remainder of the supervision tree will be started
and so the GenServer should not be required by other processes.
It can be started later with Supervisor.restart_child/2 as the child
specification is saved in the parent supervisor. The main use cases for
this are:
- The
GenServeris disabled by configuration but might be enabled later. - An error occurred and it will be handled by a different mechanism than the
Supervisor. Likely this approach involves callingSupervisor.restart_child/2after a delay to attempt a restart.
Returning {:stop, reason} will cause start_link/3 to return
{:error, reason} and the process to exit with reason reason without
entering the loop or calling c:terminate/2.
Callback implementation for GenServer.init/1.
Receive messages from the TCP socket.
Is called automatically when necessary. Should not be called manually.
Subscribe to a queue and register a callback for received messages.
Unsubscribe from a queue.