feat: add support for IPv6

.github/workflows/live-test.yaml

@@ -1,15 +1,15 @@
 name: Live test
 
 on:
-    workflow_dispatch:
-    schedule:
-      - cron: "0 0 * * *"
-    push:
-      paths:
-        - ".github/workflows/live-test.yaml"
+  workflow_dispatch:
+  schedule:
+    - cron: "0 0 * * *"
+  push:
+    paths:
+      - ".github/workflows/live-test.yaml"
 
 jobs:
-  test:
+  test-ipv4:
     runs-on: ubuntu-latest
 
     steps:
@@ -22,4 +22,22 @@ jobs:
 
       - name: Run test client
         working-directory: client
-        run: go run client.go -address coap.nordicsemi.academy
+        run: go run client.go -address coap.nordicsemi.academy
+
+  test-ipv6:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Setup Go
+        uses: actions/setup-go@v4
+        with:
+          go-version: 1.21.6
+
+      - name: Set up WARP
+        uses: fscarmen/[email protected]
+
+      - name: Run test client
+        working-directory: client
+        run: go run client.go -address coap.nordicsemi.academy -udp6

.github/workflows/test.yaml

@@ -53,4 +53,3 @@ jobs:
         run: |
           docker tag academy-coap ${{vars.REGISTRY_LOGIN_SERVER}}/coap |
           docker push ${{vars.REGISTRY_LOGIN_SERVER}}/coap
-

client/client.go

@@ -5,6 +5,7 @@ import (
 	"flag"
 	"fmt"
 	"log"
+	"net"
 	"time"
 
 	"github.com/plgd-dev/go-coap/v3/udp"
@@ -25,15 +26,31 @@ func check(e error) {
 
 func main() {
 	address := flag.String("address", "localhost",
-		"The UDP Server listen address, e.g. `localhost` or `0.0.0.0`.")
+		"The UDP Server listen address, e.g. `localhost`.")
 	password := flag.String("password", "connect:anything",
 		"The password to use for the PSK in dTLS.")
+	udp6 := flag.Bool("udp6", false, "Whether to use IPv6")
 	flag.Parse()
 
 	ctx, cancel := context.WithTimeout(context.Background(), time.Duration(10)*time.Second)
 	defer cancel()
 
-	udpAddr := fmt.Sprintf("%s:%d", *address, 5688)
+	var ip []net.IP
+	if *udp6 {
+		ip6, err := net.DefaultResolver.LookupIP(context.Background(), "ip6", *address)
+		if err != nil {
+			log.Fatal("Failed to resolve IPv6 address: ", err)
+		}
+		ip = ip6
+	} else {
+		ip4, err := net.DefaultResolver.LookupIP(context.Background(), "ip4", *address)
+		if err != nil {
+			log.Fatal("Failed to resolve IPv4 address: ", err)
+		}
+		ip = ip4
+	}
+
+	udpAddr := fmt.Sprintf("%s:%d", ip[0].String(), 5688)
 	log.Printf("UDP Server listening on: %s\n", udpAddr)
 	co, err := udp.Dial(udpAddr)
 	check(err)
@@ -44,7 +61,7 @@ func main() {
 	readId1, err := internal.TestGetCustom(co, ctx, fmt.Sprintf("/%s", id1))
 	check(err)
 	if string(readId1) != string(id1) {
-		log.Fatal(fmt.Sprintf("Read value %s is not equal written value %s.", id1, readId1))
+		log.Fatalf("Read value %s is not equal written value %s.", id1, readId1)
 	}
 
 	dtlsAddr := fmt.Sprintf("%s:%d", *address, 5689)
@@ -66,6 +83,6 @@ func main() {
 	readId2, err := internal.TestGetCustom(codTLS, ctx, fmt.Sprintf("/%s", id2))
 	check(err)
 	if string(readId2) != string(id2) {
-		log.Fatal(fmt.Sprintf("Read value %s is not equal written value %s.", id2, readId2))
+		log.Fatalf("Read value %s is not equal written value %s.", id2, readId2)
 	}
 }

server/start.sh

@@ -5,9 +5,15 @@ if [ -f $FILE ]; then
 export STORAGE_CONNECTION_STRING=$(cat /run/secrets/STORAGE_CONNECTION_STRING)
 fi 
 
-# we need to figure out the IP of the public interface here
-IP=`ip addr show eth0 | grep "inet\b" | awk '{print $2}' | cut -d/ -f1`
+# Enumerate all network interfaces and get their assigned IP addresses
+interfaces=$(ip -o addr show | awk '{print $2}' | cut -d':' -f1)
+
+for interface in $interfaces; do
+    IP=$(ip -o addr show $interface | awk '{print $4}' | cut -d'/' -f1)
+    echo "Interface: $interface, Assigned IP: $IP"
+
+    nohup /home/coap/coap-server -address "${IP}" -password "connect:anything" -dTLS &
+    nohup /home/coap/coap-server -address "${IP}" &
+done
 
-nohup /home/coap/coap-server -address "${IP}" -password "connect:anything" -dTLS &
-nohup /home/coap/coap-server -address "${IP}" &
 sleep infinity