Remove invalid hostname characters from nats client id

Signed-off-by: Edward Wilde <[email protected]>

Dockerfile

@@ -3,6 +3,7 @@ WORKDIR /go/src/github.com/openfaas/nats-queue-worker
 
 COPY vendor     vendor
 COPY handler    handler
+COPY nats       nats
 COPY main.go  .
 COPY readconfig.go .
 COPY readconfig_test.go .

Dockerfile.armhf

@@ -3,6 +3,7 @@ WORKDIR /go/src/github.com/openfaas/nats-queue-worker
 
 COPY vendor     vendor
 COPY handler    handler
+COPY nats       nats
 COPY main.go  .
 COPY readconfig.go .
 COPY readconfig_test.go .

handler/handler_test.go

@@ -1,6 +1,7 @@
 package handler
 
 import (
+	"github.com/openfaas/nats-queue-worker/nats"
 	"os"
 	"strings"
 	"testing"
@@ -12,7 +13,7 @@ func Test_GetClientID_ContainsHostname(t *testing.T) {
 	val := c.GetClientID()
 
 	hostname, _ := os.Hostname()
-	encodedHostname := supportedCharacters.ReplaceAllString(hostname, "_")
+	encodedHostname := nats.GetClientID(hostname)
 	if !strings.HasSuffix(val, encodedHostname) {
 		t.Errorf("GetClientID should contain hostname as suffix, got: %s", val)
 		t.Fail()

handler/nats_config.go

@@ -2,7 +2,8 @@ package handler
 
 import (
 	"os"
-	"regexp"
+
+	"github.com/openfaas/nats-queue-worker/nats"
 )
 
 type NatsConfig interface {
@@ -12,14 +13,12 @@ type NatsConfig interface {
 type DefaultNatsConfig struct {
 }
 
-var supportedCharacters, _ = regexp.Compile("[^a-zA-Z0-9-_]+")
-
 // GetClientID returns the ClientID assigned to this producer/consumer.
 func (DefaultNatsConfig) GetClientID() string {
 	val, _ := os.Hostname()
 	return getClientID(val)
 }
 
 func getClientID(hostname string) string {
-	return "faas-publisher-" + supportedCharacters.ReplaceAllString(hostname, "_")
+	return "faas-publisher-" + nats.GetClientID(hostname)
 }

main.go

@@ -18,6 +18,7 @@ import (
 	"github.com/nats-io/go-nats-streaming"
 	"github.com/openfaas/faas-provider/auth"
 	"github.com/openfaas/faas/gateway/queue"
+	"github.com/openfaas/nats-queue-worker/nats"
 )
 
 // AsyncReport is the report from a function executed on a queue worker.
@@ -51,12 +52,11 @@ func makeClient() http.Client {
 func main() {
 	readConfig := ReadConfig{}
 	config := readConfig.Read()
-
 	log.SetFlags(0)
 
 	clusterID := "faas-cluster"
 	val, _ := os.Hostname()
-	clientID := "faas-worker-" + val
+	clientID := "faas-worker-" + nats.GetClientID(val)
 
 	var durable string
 	var qgroup string
@@ -75,7 +75,7 @@ func main() {
 	client := makeClient()
 	sc, err := stan.Connect(clusterID, clientID, stan.NatsURL("nats://"+config.NatsAddress+":4222"))
 	if err != nil {
-		log.Fatalf("Can't connect: %v\n", err)
+		log.Fatalf("Can't connect to %s: %v\n", "nats://"+config.NatsAddress+":4222", err)
 	}
 
 	startOpt := stan.StartWithLastReceived()

nats/client.go

@@ -0,0 +1,8 @@
+package nats
+
+import "regexp"
+
+var supportedCharacters = regexp.MustCompile("[^a-zA-Z0-9-_]+")
+func GetClientID(value string) string {
+	return supportedCharacters.ReplaceAllString(value, "_")
+}

nats/client_test.go

@@ -0,0 +1,23 @@
+package nats
+
+import (
+	"testing"
+)
+
+func TestGetClientID(t *testing.T) {
+	clientID := GetClientID("computer-a")
+	want := "computer-a"
+	if clientID != want {
+		t.Logf("Want clientID: `%s`, but got: `%s`\n", want, clientID)
+		t.Fail()
+	}
+}
+
+func TestGetClientIDWhenHostHasUnsupportedCharacters(t *testing.T) {
+	clientID := GetClientID("computer-a.acme.com")
+	want := "computer-a_acme_com"
+	if clientID != want {
+		t.Logf("Want clientID: `%s`, but got: `%s`\n", want, clientID)
+		t.Fail()
+	}
+}