mqtt: add driver for syntactical sugar around virtual devices

Signed-off-by: deadprogram <ron@hybridgroup.com>

examples/mqtt_driver_ping.go

@@ -0,0 +1,41 @@
+package main
+
+import (
+	"fmt"
+	"time"
+
+	"gobot.io/x/gobot"
+	"gobot.io/x/gobot/platforms/mqtt"
+)
+
+func main() {
+	mqttAdaptor := mqtt.NewAdaptor("tcp://test.mosquitto.org:1883", "pinger")
+	holaDriver := mqtt.NewDriver(mqttAdaptor, "hola")
+	helloDriver := mqtt.NewDriver(mqttAdaptor, "hello")
+
+	work := func() {
+		helloDriver.OnData(func(data []byte) {
+			fmt.Println("hello")
+		})
+
+		holaDriver.OnData(func(data []byte) {
+			fmt.Println("hola")
+		})
+
+		data := []byte("o")
+		gobot.Every(1*time.Second, func() {
+			helloDriver.Publish(data)
+		})
+
+		gobot.Every(5*time.Second, func() {
+			holaDriver.Publish(data)
+		})
+	}
+
+	robot := gobot.NewRobot("mqttBot",
+		[]gobot.Connection{mqttAdaptor},
+		work,
+	)
+
+	robot.Start()
+}

platforms/mqtt/README.md

@@ -2,7 +2,7 @@
 
 MQTT is an Internet of Things connectivity protocol featuring a lightweight publish/subscribe messaging transport. It is useful for its small code footprint and minimal network bandwidth usage.
 
-This repository contains the Gobot adaptor/drivers to connect to MQTT servers. It uses the Paho MQTT Golang client package (https://eclipse.org/paho/) created and maintained by the Eclipse Foundation (https://github.com/eclipse) thank you!
+This repository contains the Gobot adaptor/driver to connect to MQTT servers. It uses the Paho MQTT Golang client package (https://eclipse.org/paho/) created and maintained by the Eclipse Foundation (https://github.com/eclipse) thank you!
 
 For more info about the MQTT machine to machine messaging standard, go to http://mqtt.org/
 

platforms/mqtt/mqtt_adaptor.go

@@ -41,6 +41,9 @@ func (a *Adaptor) Name() string { return a.name }
 // SetName sets the MQTT Adaptor's name
 func (a *Adaptor) SetName(n string) { a.name = n }
 
+// Port returns the Host name
+func (a *Adaptor) Port() string { return a.Host }
+
 // Connect returns true if connection to mqtt is established
 func (a *Adaptor) Connect() (err error) {
 	a.client = paho.NewClient(createClientOptions(a.clientID, a.Host, a.username, a.password))

platforms/mqtt/mqtt_driver.go

@@ -0,0 +1,66 @@
+package mqtt
+
+import "gobot.io/x/gobot"
+
+// Driver for mqtt
+type Driver struct {
+	name       string
+	topic      string
+	connection gobot.Connection
+	gobot.Eventer
+	gobot.Commander
+}
+
+// NewDriver returns a new Gobot MQTT Driver
+func NewDriver(a *Adaptor, topic string) *Driver {
+	m := &Driver{
+		name:       "MQTT",
+		topic:      topic,
+		connection: a,
+		Eventer:    gobot.NewEventer(),
+		Commander:  gobot.NewCommander(),
+	}
+
+	return m
+}
+
+// Name returns name for the Driver
+func (m *Driver) Name() string { return m.name }
+
+// Name sets name for the Driver
+func (m *Driver) SetName(name string) { m.name = name }
+
+// Connection returns Connections used by the Driver
+func (m *Driver) Connection() gobot.Connection {
+	return m.connection
+}
+
+func (m *Driver) adaptor() *Adaptor {
+	return m.Connection().(*Adaptor)
+}
+
+// Start starts the Driver
+func (m *Driver) Start() error {
+	return nil
+}
+
+// Halt halts the Driver
+func (m *Driver) Halt() error {
+	return nil
+}
+
+// Topic returns the current topic for the Driver
+func (m *Driver) Topic() string { return m.topic }
+
+// SetTopic sets the current topic for the Driver
+func (m *Driver) SetTopic(topic string) { m.topic = topic }
+
+// Publish a message to the current device topic
+func (m *Driver) Publish(message []byte) bool {
+	return m.adaptor().Publish(m.topic, message)
+}
+
+// OnData subscribes to the current device topic, and then calls the message handler function when data is received
+func (m *Driver) OnData(f func(s []byte)) bool {
+	return m.adaptor().On(m.topic, f)
+}

platforms/mqtt/mqtt_driver_test.go

@@ -0,0 +1,20 @@
+package mqtt
+
+import (
+	"testing"
+
+	"gobot.io/x/gobot"
+	"gobot.io/x/gobot/gobottest"
+)
+
+var _ gobot.Driver = (*Driver)(nil)
+
+func TestMqttDriver(t *testing.T) {
+	d := NewDriver(initTestMqttAdaptor(), "/test/topic")
+
+	gobottest.Assert(t, d.Name(), "MQTT")
+	gobottest.Assert(t, d.Connection().Name(), "MQTT")
+
+	gobottest.Assert(t, d.Start(), nil)
+	gobottest.Assert(t, d.Halt(), nil)
+}