HL7v2.MLLP.Handler behaviour (HL7v2 v3.10.1)

Behaviour for MLLP message handlers.

Implement handle_message/2 to process incoming HL7v2 messages and return a response. The handler receives the raw HL7v2 message (without MLLP framing) and connection metadata. The returned response message will be MLLP-framed before sending back to the client.

Example

defmodule MyHandler do
  @behaviour HL7v2.MLLP.Handler

  @impl true
  def handle_message(message, _meta) do
    # Parse, process, build ACK...
    {:ok, ack_message}
  end
end

Connection metadata

The meta map contains:

:peer — {address, port} of the remote client
:ref — the Ranch listener reference
:handler_state — the value passed as :handler_state to the listener

Summary

Types

meta()

Callbacks

handle_message(message, meta)

Handles an incoming HL7v2 message.

Types

meta()

@type meta() :: %{
  peer: {:inet.ip_address(), :inet.port_number()},
  ref: :ranch.ref(),
  handler_state: term()
}

Callbacks

handle_message(message, meta)

@callback handle_message(message :: binary(), meta :: meta()) ::
  {:ok, response :: binary()} | {:error, reason :: term()}

Handles an incoming HL7v2 message.

Receives the raw message binary (MLLP framing already stripped) and connection metadata. Must return {:ok, response_binary} or {:error, reason}.