MQTT - Qatja ability to connect using username and password ?

smartRF

Many cloud services use MQTT and they require an initial connection using a username and password. I have not found the ability to set these parameters with any of the MQTT type libraries i have found for processing. Is this capability available ?

jsotola

here is an example from the mqtt library

i added a few client connect strings

the one for broker.shiftr.io has user and password strings

the code publishes a message with every key press

it also times out in 15 seconds

try uncommenting some of the other client.connect command lines (only one at a time)

and try some of the other subscriptions

test.mosquitto.org has a lot of messages in the $SYS subscriptions

hope this helps

you may already know all of this, but someone else may not

    // This example sketch connects to shiftr.io
    // and sends a message on every kestroke.
    //
    // After starting the sketch you can find the
    // client here: [https://shiftr.io/try]
    //
    // by Joël Gähwiler
    // [https://github.com/256dpi/procssing-mqtt]

    import mqtt.*;

    int time;
    int wait = 15000;    // milliseconds (15 seconds)


    MQTTClient client;

    void setup() {
      client = new MQTTClient(this);

      client.connect("mqtt://try:try@broker.shiftr.io", "ESP8266Client");  // try:try = user:pwd

    //  client.connect("mqtt://iot.eclipse.org");
    //  client.connect("mqtt://test.mosquitto.org", "ESP8266Client");
    //  client.connect("mqtt://test.mosquitto.org");

    //  client.subscribe("$SYS/#");    // # - all, + - one
    //  client.subscribe("$SYS/+/+");
    //  client.subscribe("bbc/subtitles/bbc_news24/raw");

      client.subscribe("/example");
      client.subscribe("$SYS/broker/log/M/#");

    time = millis();

    }

    void draw() {

      if (millis() > (time + wait)) {
        client.unsubscribe("$SYS/broker/log/M/#");
        client.unsubscribe("ssjh/#");
        client.unsubscribe("/example");
        println("done");
        exit();
      } 
    }

    void keyPressed() { client.publish("/example", "pressed key - " + char(key)); }

    void messageReceived(String topic, byte[] payload) {
      println("new message: " + topic + " - " + new String(payload));
    }

jsotola

some of the code got messed up by the forum software

the beginning of the code should read as follows

// This example sketch connects to shiftr.io

// and sends a message on every kestroke.

//

// After starting the sketch you can find the

// client here: https://shiftr.io/try.

//

// by Joël Gähwiler

// https://github.com/256dpi/processing-mqtt

smartRF

Thank you Joel

your example obviously works with your broker but when i try to use this format with the service i want to work with, i get the following:

MQTT 1.6.1 by Joel Gaehwiler https://github.com/256dpi

[MQTT] failed to connect: MqttException

[MQTT] failed to subscribe: Client is not connected

here is the client connect format i am trying to use, where the user name is the 70B3.... section and the pw is the xPD8..... section (replacing your try:try )

are these incompatible with this implementation ? or did i not implement it properly ?

i can use this user/pw with other clients on an Android device or MQTTlens on a pc and it works just fine. I would like to be able to do the same with processing.

let me know if you have any suggestions.

client.connect("mqtt://70B3D57ED00009CB:xPD8muP6/3ZG0q8IMudHS4cAKpynuwTeEQeGOxtQxT4=@staging.thethingsnetwork.org","processing55AA"); // try:try = user:pwd

thanks Ken

jsotola

it is the forward slash in the password that throws the exception

without it you get "[MQTT] failed to connect: Not authorized to connect"

btw. i am not joel

jsotola

it is because the string is a URL, therefore the slash has to be escaped with %2F (replaced)

see http://w3schools.com/tags/ref_urlencode.asp

this should work

  client.connect("mqtt://70B3D57ED00009CB:xPD8muP6%2F3ZG0q8IMudHS4cAKpynuwTeEQeGOxtQxT4%3D@staging.thethingsnetwork.org","processing55AA");

smartRF

That solved the issue.

Now i am able to connect and subscribe and publish properly thru this broker using the test account i used as an example. thanks for taking the time to provide a solution and explanation regarding URL encodeing.

Ken