espat: implement MQTT subscribe functionality via blocking select/channels.

also refactor response processing for greater speed and efficiency.

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

examples/espat/espconsole/main.go

@@ -26,7 +26,7 @@ const pass = "YOURPASS"
 // these are the default pins for the Arduino Nano33 IoT.
 // change these to connect to a different UART or pins for the ESP8266/ESP32
 var (
-	uart = machine.UART2
+	uart = machine.UART1
 	tx   = machine.PA22
 	rx   = machine.PA23
 
@@ -43,28 +43,20 @@ func main() {
 	adaptor.Configure()
 
 	// first check if connected
-	if adaptor.Connected() {
+	if connectToESP() {
+		println("Connected to wifi adaptor.")
 		adaptor.Echo(false)
-		console.Write([]byte("\r\n"))
-		console.Write([]byte("ESP-AT console enabled.\r\n"))
-		console.Write([]byte("Firmware version:\r\n"))
-		console.Write(adaptor.Version())
-		console.Write([]byte("\r\n"))
 
-		if actAsAP {
-			provideAP()
-		} else {
-			connectToAP()
-		}
-
-		console.Write([]byte("Type an AT command then press enter:\r\n"))
-		prompt()
+		connectToAP()
 	} else {
-		console.Write([]byte("\r\n"))
-		console.Write([]byte("Unable to connect to wifi adaptor.\r\n"))
+		println("")
+		failMessage("Unable to connect to wifi adaptor.")
 		return
 	}
 
+	println("Type an AT command then press enter:")
+	prompt()
+
 	input := make([]byte, 64)
 	i := 0
 	for {
@@ -82,7 +74,8 @@ func main() {
 				adaptor.Write(input[:i+2])
 
 				// display response
-				console.Write(adaptor.Response(100))
+				r, _ := adaptor.Response(500)
+				console.Write(r)
 
 				// prompt
 				prompt()
@@ -101,28 +94,50 @@ func main() {
 }
 
 func prompt() {
-	console.Write([]byte("ESPAT>"))
+	print("ESPAT>")
+}
+
+// connect to ESP8266/ESP32
+func connectToESP() bool {
+	for i := 0; i < 5; i++ {
+		println("Connecting to wifi adaptor...")
+		if adaptor.Connected() {
+			return true
+		}
+		time.Sleep(1 * time.Second)
+	}
+	return false
 }
 
 // connect to access point
 func connectToAP() {
-	console.Write([]byte("Connecting to wifi network...\r\n"))
+	println("Connecting to wifi network '" + ssid + "'")
+
 	adaptor.SetWifiMode(espat.WifiModeClient)
 	adaptor.ConnectToAP(ssid, pass, 10)
-	console.Write([]byte("Connected.\r\n"))
-	console.Write([]byte(adaptor.GetClientIP()))
-	console.Write([]byte("\r\n"))
+
+	println("Connected.")
+	ip, err := adaptor.GetClientIP()
+	if err != nil {
+		failMessage(err.Error())
+	}
+
+	println(ip)
 }
 
 // provide access point
 func provideAP() {
-	time.Sleep(500 * time.Millisecond)
-	console.Write([]byte("Starting wifi network as access point '"))
-	console.Write([]byte(ssid))
-	console.Write([]byte("'...\r\n"))
+	println("Starting wifi network as access point '" + ssid + "'...")
 	adaptor.SetWifiMode(espat.WifiModeAP)
 	adaptor.SetAPConfig(ssid, pass, 7, espat.WifiAPSecurityWPA2_PSK)
-	console.Write([]byte("Ready.\r\n"))
-	console.Write([]byte(adaptor.GetAPIP()))
-	console.Write([]byte("\r\n"))
+	println("Ready.")
+	ip, _ := adaptor.GetAPIP()
+	println(ip)
+}
+
+func failMessage(msg string) {
+	for {
+		println(msg)
+		time.Sleep(1 * time.Second)
+	}
 }

examples/espat/esphub/main.go

@@ -24,7 +24,7 @@ const pass = "YOURPASS"
 // these are the default pins for the Arduino Nano33 IoT.
 // change these to connect to a different UART or pins for the ESP8266/ESP32
 var (
-	uart = machine.UART2
+	uart = machine.UART1
 	tx   = machine.PA22
 	rx   = machine.PA23
 
@@ -43,17 +43,14 @@ func main() {
 	readyled.High()
 
 	// first check if connected
-	if adaptor.Connected() {
+	if connectToESP() {
 		println("Connected to wifi adaptor.")
 		adaptor.Echo(false)
 
-		if actAsAP {
-			provideAP()
-		} else {
-			connectToAP()
-		}
+		connectToAP()
 	} else {
-		println("Unable to connect to wifi adaptor.")
+		println("")
+		failMessage("Unable to connect to wifi adaptor.")
 		return
 	}
 
@@ -86,21 +83,47 @@ func main() {
 	println("Done.")
 }
 
+// connect to ESP8266/ESP32
+func connectToESP() bool {
+	for i := 0; i < 5; i++ {
+		println("Connecting to wifi adaptor...")
+		if adaptor.Connected() {
+			return true
+		}
+		time.Sleep(1 * time.Second)
+	}
+	return false
+}
+
 // connect to access point
 func connectToAP() {
-	println("Connecting to wifi network...")
+	println("Connecting to wifi network '" + ssid + "'")
+
 	adaptor.SetWifiMode(espat.WifiModeClient)
 	adaptor.ConnectToAP(ssid, pass, 10)
+
 	println("Connected.")
-	println(adaptor.GetClientIP())
+	ip, err := adaptor.GetClientIP()
+	if err != nil {
+		failMessage(err.Error())
+	}
+
+	println(ip)
 }
 
 // provide access point
 func provideAP() {
-	println("Starting wifi network as access point:")
-	println(ssid)
+	println("Starting wifi network as access point '" + ssid + "'...")
 	adaptor.SetWifiMode(espat.WifiModeAP)
 	adaptor.SetAPConfig(ssid, pass, 7, espat.WifiAPSecurityWPA2_PSK)
 	println("Ready.")
-	println(adaptor.GetAPIP())
+	ip, _ := adaptor.GetAPIP()
+	println(ip)
+}
+
+func failMessage(msg string) {
+	for {
+		println(msg)
+		time.Sleep(1 * time.Second)
+	}
 }

examples/espat/espstation/main.go

@@ -24,7 +24,7 @@ const hubIP = "0.0.0.0"
 // these are the default pins for the Arduino Nano33 IoT.
 // change these to connect to a different UART or pins for the ESP8266/ESP32
 var (
-	uart = machine.UART2
+	uart = machine.UART1
 	tx   = machine.PA22
 	rx   = machine.PA23
 
@@ -39,13 +39,14 @@ func main() {
 	adaptor.Configure()
 
 	// first check if connected
-	if adaptor.Connected() {
+	if connectToESP() {
 		println("Connected to wifi adaptor.")
 		adaptor.Echo(false)
 
 		connectToAP()
 	} else {
-		println("Unable to connect to wifi adaptor.")
+		println("")
+		failMessage("Unable to connect to wifi adaptor.")
 		return
 	}
 
@@ -71,11 +72,37 @@ func main() {
 	println("Done.")
 }
 
+// connect to ESP8266/ESP32
+func connectToESP() bool {
+	for i := 0; i < 5; i++ {
+		println("Connecting to wifi adaptor...")
+		if adaptor.Connected() {
+			return true
+		}
+		time.Sleep(1 * time.Second)
+	}
+	return false
+}
+
 // connect to access point
 func connectToAP() {
-	println("Connecting to wifi network...")
+	println("Connecting to wifi network '" + ssid + "'")
+
 	adaptor.SetWifiMode(espat.WifiModeClient)
 	adaptor.ConnectToAP(ssid, pass, 10)
+
 	println("Connected.")
-	println(adaptor.GetClientIP())
+	ip, err := adaptor.GetClientIP()
+	if err != nil {
+		failMessage(err.Error())
+	}
+
+	println(ip)
+}
+
+func failMessage(msg string) {
+	for {
+		println(msg)
+		time.Sleep(1 * time.Second)
+	}
 }

examples/espat/mqttclient/main.go

@@ -25,8 +25,9 @@ const ssid = "YOURSSID"
 const pass = "YOURPASS"
 
 // IP address of the MQTT broker to use. Replace with your own info.
-//const server = "tcp://test.mosquitto.org:1883"
-const server = "ssl://test.mosquitto.org:8883"
+const server = "tcp://test.mosquitto.org:1883"
+
+//const server = "ssl://test.mosquitto.org:8883"
 
 // these are the default pins for the Arduino Nano33 IoT.
 // change these to connect to a different UART or pins for the ESP8266/ESP32
@@ -66,7 +67,7 @@ func main() {
 	opts := mqtt.NewClientOptions(adaptor)
 	opts.AddBroker(server).SetClientID("tinygo-client-" + randomString(10))
 
-	println("Connectng to MQTT...")
+	println("Connecting to MQTT broker at", server)
 	cl := mqtt.NewClient(opts)
 	if token := cl.Connect(); token.Wait() && token.Error() != nil {
 		failMessage(token.Error().Error())
@@ -105,13 +106,18 @@ func connectToESP() bool {
 
 // connect to access point
 func connectToAP() {
-	println("Connecting to wifi network...")
+	println("Connecting to wifi network '" + ssid + "'")
 
 	adaptor.SetWifiMode(espat.WifiModeClient)
 	adaptor.ConnectToAP(ssid, pass, 10)
 
 	println("Connected.")
-	println(adaptor.GetClientIP())
+	ip, err := adaptor.GetClientIP()
+	if err != nil {
+		failMessage(err.Error())
+	}
+
+	println(ip)
 }
 
 // Returns an int >= min, < max

examples/espat/mqttsub/main.go

@@ -0,0 +1,163 @@
+// This is a sensor station that uses a ESP8266 or ESP32 running on the device UART1.
+// It creates an MQTT connection that publishes a message every second
+// to an MQTT broker.
+//
+// In other words:
+// Your computer <--> UART0 <--> MCU <--> UART1 <--> ESP8266 <--> Internet <--> MQTT broker.
+//
+// You must also install the Paho MQTT package to build this program:
+//
+// 		go get -u github.com/eclipse/paho.mqtt.golang
+//
+package main
+
+import (
+	"fmt"
+	"machine"
+	"math/rand"
+	"time"
+
+	"tinygo.org/x/drivers/espat"
+	"tinygo.org/x/drivers/espat/mqtt"
+)
+
+// access point info
+const ssid = "YOURSSID"
+const pass = "YOURPASS"
+
+// IP address of the MQTT broker to use. Replace with your own info.
+//const server = "tcp://test.mosquitto.org:1883"
+
+const server = "ssl://test.mosquitto.org:8883"
+
+// change these to connect to a different UART or pins for the ESP8266/ESP32
+var (
+	// these are defaults for the Arduino Nano33 IoT.
+	uart = machine.UART1
+	tx   = machine.PA22
+	rx   = machine.PA23
+
+	console = machine.UART0
+
+	adaptor *espat.Device
+	cl      mqtt.Client
+	topicTx = "tinygo/tx"
+	topicRx = "tinygo/rx"
+)
+
+func subHandler(client mqtt.Client, msg mqtt.Message) {
+	fmt.Printf("[%s]  ", msg.Topic())
+	fmt.Printf("%s\r\n", msg.Payload())
+}
+
+func main() {
+	time.Sleep(3000 * time.Millisecond)
+
+	uart.Configure(machine.UARTConfig{TX: tx, RX: rx})
+	rand.Seed(time.Now().UnixNano())
+
+	// Init esp8266/esp32
+	adaptor = espat.New(uart)
+	adaptor.Configure()
+
+	// first check if connected
+	if connectToESP() {
+		println("Connected to wifi adaptor.")
+		adaptor.Echo(false)
+
+		connectToAP()
+	} else {
+		println("")
+		failMessage("Unable to connect to wifi adaptor.")
+		return
+	}
+
+	opts := mqtt.NewClientOptions(adaptor)
+	opts.AddBroker(server).SetClientID("tinygo-client-" + randomString(10))
+
+	println("Connecting to MQTT broker at", server)
+	cl = mqtt.NewClient(opts)
+	if token := cl.Connect(); token.Wait() && token.Error() != nil {
+		failMessage(token.Error().Error())
+	}
+
+	// subscribe
+	token := cl.Subscribe(topicRx, 0, subHandler)
+	token.Wait()
+	if token.Error() != nil {
+		failMessage(token.Error().Error())
+	}
+
+	go publishing()
+
+	select {}
+
+	// Right now this code is never reached. Need a way to trigger it...
+	println("Disconnecting MQTT...")
+	cl.Disconnect(100)
+
+	println("Done.")
+}
+
+func publishing() {
+	for {
+		println("Publishing MQTT message...")
+		data := []byte("{\"e\":[{ \"n\":\"hello\", \"v\":101 }]}")
+		token := cl.Publish(topicTx, 0, false, data)
+		token.Wait()
+		if token.Error() != nil {
+			println(token.Error().Error())
+		}
+
+		time.Sleep(1000 * time.Millisecond)
+	}
+}
+
+// connect to ESP8266/ESP32
+func connectToESP() bool {
+	for i := 0; i < 5; i++ {
+		println("Connecting to wifi adaptor...")
+		if adaptor.Connected() {
+			return true
+		}
+		time.Sleep(1 * time.Second)
+	}
+	return false
+}
+
+// connect to access point
+func connectToAP() {
+	println("Connecting to wifi network '" + ssid + "'")
+
+	adaptor.SetWifiMode(espat.WifiModeClient)
+	adaptor.ConnectToAP(ssid, pass, 10)
+
+	println("Connected.")
+	ip, err := adaptor.GetClientIP()
+	if err != nil {
+		failMessage(err.Error())
+	}
+
+	println(ip)
+}
+
+// Returns an int >= min, < max
+func randomInt(min, max int) int {
+	return min + rand.Intn(max-min)
+}
+
+// Generate a random string of A-Z chars with len = l
+func randomString(len int) string {
+	bytes := make([]byte, len)
+	for i := 0; i < len; i++ {
+		bytes[i] = byte(randomInt(65, 90))
+	}
+	return string(bytes)
+}
+
+func failMessage(msg string) {
+	for {
+		println(msg)
+		time.Sleep(1 * time.Second)
+	}
+}

examples/espat/tcpclient/main.go

@@ -24,7 +24,7 @@ const serverIP = "0.0.0.0"
 // these are the default pins for the Arduino Nano33 IoT.
 // change these to connect to a different UART or pins for the ESP8266/ESP32
 var (
-	uart = machine.UART2
+	uart = machine.UART1
 	tx   = machine.PA22
 	rx   = machine.PA23
 
@@ -39,13 +39,14 @@ func main() {
 	adaptor.Configure()
 
 	// first check if connected
-	if adaptor.Connected() {
+	if connectToESP() {
 		println("Connected to wifi adaptor.")
 		adaptor.Echo(false)
 
 		connectToAP()
 	} else {
-		println("Unable to connect to wifi adaptor.")
+		println("")
+		failMessage("Unable to connect to wifi adaptor.")
 		return
 	}
 
@@ -55,7 +56,10 @@ func main() {
 	laddr := &net.TCPAddr{Port: 8080}
 
 	println("Dialing TCP connection...")
-	conn, _ := net.DialTCP("tcp", laddr, raddr)
+	conn, err := net.DialTCP("tcp", laddr, raddr)
+	if err != nil {
+		failMessage(err.Error())
+	}
 
 	for {
 		// send data
@@ -71,11 +75,37 @@ func main() {
 	println("Done.")
 }
 
+// connect to ESP8266/ESP32
+func connectToESP() bool {
+	for i := 0; i < 5; i++ {
+		println("Connecting to wifi adaptor...")
+		if adaptor.Connected() {
+			return true
+		}
+		time.Sleep(1 * time.Second)
+	}
+	return false
+}
+
 // connect to access point
 func connectToAP() {
-	println("Connecting to wifi network...")
+	println("Connecting to wifi network '" + ssid + "'")
+
 	adaptor.SetWifiMode(espat.WifiModeClient)
 	adaptor.ConnectToAP(ssid, pass, 10)
+
 	println("Connected.")
-	println(adaptor.GetClientIP())
+	ip, err := adaptor.GetClientIP()
+	if err != nil {
+		failMessage(err.Error())
+	}
+
+	println(ip)
+}
+
+func failMessage(msg string) {
+	for {
+		println(msg)
+		time.Sleep(1 * time.Second)
+	}
 }