Guile MQTT provides bindings for the libmosquitto MQTT client library. The
bindings are written in [GOOPS](https://www.gnu.org/software/guile
/manual/html_node/GOOPS.html) and rely on lower-level bindings created by
NYACC directly and automatically from mosquitto.h.
Changes compared to v0.2.1:
* Major version bumped to 1 to indicate reasonable stability.
* Bugfix: Support publishing of UTF-8 strings. (Thanks to Evgeny Pisemsky.)
* Get ready for the Guile 4.0 release.
The bindings align with GOOPS style, which means short method names. (The
specialization is done through the arguments.)
The user can extend the client class by inheritance.
Guile MQTT is free software and is released under the LGPL v3 license; the
full source distribution is available through
* a tarball:
https://github.com/mdjurfeldt/guile-mqtt/releases/download/v1.0.0/guile
-mqtt-1.0.0.tar.gz
<https://github.com/mdjurfeldt/guile-mqtt/releases/download/v0.2.0/guile-mqtt-0.2.0.tar.gz>
* the git repository:
https://github.com/mdjurfeldt/guile-mqtt
The following example, as well as the Guile libmosquitto bindings
themselves, are inspired by the [Chicken Scheme mosquitto bindings](
http://wiki.call-cc.org/eggref/5/mosquitto) by Dmitrii Kosenkov.
```
(use-modules (mosquitto client))
(let ((client (make-client #:on-connect
(lambda (client err)
(if (not (eq? err MOSQ_ERR_SUCCESS))
(abort err)
(display "Yay, we are connected!"))))))
(set! (disconnect-callback client)
(lambda (client err)
(if (not (eq? err MOSQ_ERR_SUCCESS))
(display "Unexpected disconnect..."))))
(set! (message-callback client)
(lambda (cl msg)
(display (string->append "Topic: " (topic msg)
"Payload:" payload msg))
(publish client "topic2" "message received, thanks!")))
(connect client "localhost" #:username "mqtt-admin" #:password "mypass")
(subscribe client "topic1")
(loop-forever client))
```
See further examples under the directory [examples](
https://github.com/mdjurfeldt/guile-mqqt/tree/main/examples).
