initial import

cloud-provider/docker-compose/Dockerfile.receiver

@@ -0,0 +1,13 @@
+FROM golang:1 as builder
+
+WORKDIR /go/src/app
+
+COPY go.* ./
+RUN go mod download
+
+COPY . .
+RUN CGO_ENABLED=0 go build -o app ./cmd/receiver
+
+FROM alpine:latest
+COPY --from=builder /go/src/app .
+CMD ["./app"]

cloud-provider/docker-compose/Dockerfile.sender

@@ -0,0 +1,13 @@
+FROM golang:1 as builder
+
+WORKDIR /go/src/app
+
+COPY go.* ./
+RUN go mod download
+
+COPY . .
+RUN CGO_ENABLED=0 go build -o app ./cmd/sender
+
+FROM alpine:latest
+COPY --from=builder /go/src/app .
+CMD ["./app"]

cloud-provider/docker-compose/cmd/receiver/main.go

@@ -0,0 +1,70 @@
+package main
+
+import (
+	"context"
+	"log"
+	"os"
+	"sync"
+	"time"
+
+	"github.com/nats-io/nats.go"
+)
+
+type Message struct {
+	Text string
+}
+
+func connectNATS(ctx context.Context, url string) (*nats.Conn, error) {
+	var err error
+	for {
+		select {
+		case <-ctx.Done():
+			return nil, err
+		default:
+			var nc *nats.Conn
+			nc, err = nats.Connect(url)
+			if err == nil {
+				return nc, err
+			}
+		}
+	}
+
+}
+
+func main() {
+
+	url := nats.DefaultURL
+	if v, ok := os.LookupEnv("NATS_URL"); ok {
+		url = v
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+	defer cancel()
+	nc, err := connectNATS(ctx, url)
+	if err != nil {
+		log.Fatalf("Could not connect to server because of %v", err)
+	}
+	defer nc.Close()
+	log.Println("successfully connected to NATS server")
+
+	c, _ := nats.NewEncodedConn(nc, nats.JSON_ENCODER)
+	defer c.Close()
+
+	wg := sync.WaitGroup{}
+	wg.Add(1)
+
+	sub, err := c.Subscribe("testing", func(message *Message) {
+		log.Printf("neue Nachricht %+v", message)
+	})
+
+	if err != nil {
+		log.Fatalf("Could not subscribe because of %v", err)
+	}
+
+	log.Printf("Warte auf Nachrichten")
+	wg.Wait()
+
+	sub.Unsubscribe()
+	sub.Drain()
+
+}

cloud-provider/docker-compose/cmd/sender/main.go

@@ -0,0 +1,44 @@
+package main
+
+import (
+	"log"
+	"os"
+	"time"
+
+	"github.com/nats-io/nats.go"
+)
+
+type Message struct {
+	Text string
+}
+
+func sendMessage(url string) error {
+	nc, err := nats.Connect(url)
+	if err != nil {
+		return err
+	}
+	defer nc.Close()
+	c, _ := nats.NewEncodedConn(nc, nats.JSON_ENCODER)
+	defer c.Close()
+
+	return c.Publish("testing", &Message{"Hello World"})
+}
+
+func main() {
+
+	url := nats.DefaultURL
+	if v, ok := os.LookupEnv("NATS_URL"); ok {
+		url = v
+	}
+
+	for {
+		err := sendMessage(url)
+		if err != nil {
+			log.Println(err)
+		} else {
+			log.Println("Nachricht versendet")
+		}
+		time.Sleep(4 * time.Second)
+	}
+
+}

cloud-provider/docker-compose/docker-compose.yml

@@ -0,0 +1,16 @@
+version: '3'
+services:
+  sender-application:
+    build:
+      context: .
+      dockerfile: Dockerfile.sender
+    environment:
+      NATS_URL: "nats://nats-server:4222"
+  receiver-application:
+    build:
+      context: .
+      dockerfile: Dockerfile.receiver
+    environment:
+        NATS_URL: "nats://nats-server:4222"
+  nats-server:
+    image: nats

cloud-provider/docker-compose/go.mod

@@ -0,0 +1,5 @@
+module golang.source-fellows.com/samples/cloud/dockercompose
+
+go 1.14
+
+require github.com/nats-io/nats.go v1.10.0 // indirect

cloud-provider/docker-compose/go.sum

@@ -0,0 +1,17 @@
+github.com/nats-io/jwt v0.3.2 h1:+RB5hMpXUUA2dfxuhBTEkMOrYmM+gKIZYS1KjSostMI=
+github.com/nats-io/jwt v0.3.2/go.mod h1:/euKqTS1ZD+zzjYrY7pseZrTtWQSjujC7xjPc8wL6eU=
+github.com/nats-io/nats.go v1.10.0 h1:L8qnKaofSfNFbXg0C5F71LdjPRnmQwSsA4ukmkt1TvY=
+github.com/nats-io/nats.go v1.10.0/go.mod h1:AjGArbfyR50+afOUotNX2Xs5SYHf+CoOa5HH1eEl2HE=
+github.com/nats-io/nkeys v0.1.3/go.mod h1:xpnFELMwJABBLVhffcfd1MZx6VsNRFpEugbxziKVo7w=
+github.com/nats-io/nkeys v0.1.4 h1:aEsHIssIk6ETN5m2/MD8Y4B2X7FfXrBAUdkyRvbVYzA=
+github.com/nats-io/nkeys v0.1.4/go.mod h1:XdZpAbhgyyODYqjTawOnIOI7VlbKSarI9Gfy1tqEu/s=
+github.com/nats-io/nuid v1.0.1 h1:5iA8DT8V7q8WK2EScv2padNa/rTESc1KdnPw4TC2paw=
+github.com/nats-io/nuid v1.0.1/go.mod h1:19wcPz3Ph3q0Jbyiqsd0kePYG7A95tJPxeL+1OSON2c=
+golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
+golang.org/x/crypto v0.0.0-20190701094942-4def268fd1a4/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
+golang.org/x/crypto v0.0.0-20200323165209-0ec3e9974c59 h1:3zb4D3T4G8jdExgVU/95+vQXfpEPiMdCaZgmGVxjNHM=
+golang.org/x/crypto v0.0.0-20200323165209-0ec3e9974c59/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
+golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
+golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=