MQTT in Processing
see also MQTT Brokers and https://www.kobakant.at/DIY/?p=9140
Shiftr has libraries for various platforms including Arduino and Processing that make it very easy to code MQTT Clients.
SHIFTR ONLINE
To code a Proccessing Client we use Shiftr's MQTT library for Processing.
Install Library
Sketch --> Import Library --> Add Library --> filter: "MQTT" install "MQTT library for Processing based on the Eclipse Paho project by Joel Gaehwiller"
Open Example
File --> Examples --> MQTT --> "PublishSubscribe"
The following line of code connects you to the online Shiftr Broker's public namespace called "try" with the Client ID "processing".
client.connect("mqtt://public:public@public.cloud.shiftr.io", "processing");
Notes: Make sure the URL in your code is the same as the current URL shown on the public namespace website:
"mqtt://public:public@public.cloud.shiftr.io"
If you are using your own namespace, make sure you edit the URL to include:
name_of_your_instance
token_secret
url_of_your_instance
"mqtt://name_of_your_instance:token_secret@url_of_your_instance.cloud.shiftr.io"
if you need to use a different port number other than the default 1883 (for example 2883), you can specify it like this:
"mqtt://name_of_your_instance:token_secret@url_of_your_instance.cloud.shiftr.io:2883"
SHIFTR Desktop App
Download the Shiftr MQTT library (see above).
Open the Shiftr MQTT example (see above).
Insert your IP address instead of the Shiftr URL:
client.connect("mqtt://192.168.0.9", "processing”);
if you need to use a different port number other than the default 1883 (for example 2883), you can specify it like this:
client.connect("mqtt://192.168.0.9:2883", "processing”);