This is a library based on PubSubClient (knolleary) and some modifications made by @diegopx and me.
This library provides an MQTT client that is capable of TLS connection with certificate chain verification (and SNI).
In addition, by using setCertHostName
method, the hostname in the certificate can be overridden. This is useful when you need to provide a different SNI other than the hostname written into the server certificate.
Below you can find the original manual. Note: modifications above works only on ESP8266/NodeMCU.
This library is a fork intended for drop-in replacement, so it cannot be used with the official PubSubClient at the same time
This library provides a client for doing simple publish/subscribe messaging with a server that supports MQTT.
The library comes with a number of example sketches. See File > Examples > PubSubClient within the Arduino application.
Full API documentation is available here: http://pubsubclient.knolleary.net
- It can only publish QoS 0 messages. It can subscribe at QoS 0 or QoS 1.
- The maximum message size, including header, is 128 bytes by default. This
is configurable via
MQTT_MAX_PACKET_SIZE
inPubSubClient.h
. - The keepalive interval is set to 15 seconds by default. This is configurable
via
MQTT_KEEPALIVE
inPubSubClient.h
. - The client uses MQTT 3.1.1 by default. It can be changed to use MQTT 3.1 by
changing value of
MQTT_VERSION
inPubSubClient.h
.
The library uses the Arduino Ethernet Client api for interacting with the underlying network hardware. This means it Just Works with a growing number of boards and shields, including:
- Arduino Ethernet
- Arduino Ethernet Shield
- Arduino YUN – use the included
YunClient
in place ofEthernetClient
, and be sure to do aBridge.begin()
first - Arduino WiFi Shield - if you want to send packets > 90 bytes with this shield,
enable the
MQTT_MAX_TRANSFER_SIZE
define inPubSubClient.h
. - Sparkfun WiFly Shield – library
- TI CC3000 WiFi - library
- Intel Galileo/Edison
- ESP8266
The library cannot currently be used with hardware based on the ENC28J60 chip – such as the Nanode or the Nuelectronics Ethernet Shield. For those, there is an alternative library available.
This code is released under the MIT License.