This library implements the client MQTT v3 protocol.
Originally forked from https://github.com/j0sh/ocaml-mqtt.
Install the packaage:
$ opam install mqtt
In your dune project add the following dependencies to your dune file:
(executable
(name My_app)
(public_name my_app)
(libraries mqtt.client lwt)
(preprocess (pps lwt_ppx)))
Here is a basic example of a subscriber:
module C = Mqtt_client
let host = "127.0.0.1"
let port = 1883
let sub_example () =
let on_message ~topic payload = Lwt_io.printlf "%s: %s" topic payload in
let%lwt () = Lwt_io.printl "Starting subscriber..." in
let%lwt client = C.connect ~on_message ~id:"client-1" ~port [ host ] in
C.subscribe [ ("topic-1", C.Atmost_once) ] client
let pub_example () =
let%lwt () = Lwt_io.printl "Starting publisher..." in
let%lwt client = C.connect ~id:"client-1" ~port [ host ] in
let rec loop () =
let%lwt () = Lwt_io.printl "Publishing..." in
let%lwt line = Lwt_io.read_line Lwt_io.stdin in
let%lwt () = C.publish ~qos:C.Atleast_once ~topic:"topic-1" line client in
let%lwt () = Lwt_io.printl "Published." in
loop ()
in
loop ()
let () = Lwt_main.run (sub_example ())