Update nats-queue-worker package to 0.4.7

This package version supports running OpenFaas on hosts the contain `.`
in their hostname i.e. computer-a.acme.com

Signed-off-by: Edward Wilde <ewilde@gmail.com>

gateway/vendor/github.com/openfaas/nats-queue-worker/.travis.yml

@@ -17,7 +17,7 @@ install:
   - echo "Please don't go get"
 
 script:
-  - cd queue-worker && ./build.sh
+  - ./build.sh
 
 after_success:
     - if [ ! -z "$TRAVIS_TAG" ] ; then

gateway/vendor/github.com/openfaas/nats-queue-worker/Gopkg.toml

@@ -33,6 +33,10 @@
   name = "github.com/openfaas/faas"
   version = "0.8.2"
 
+[[constraint]]
+  name = "github.com/nats-io/go-nats"
+  version = "v1.5.0"
+
 [prune]
   go-tests = true
   unused-packages = true

gateway/vendor/github.com/openfaas/nats-queue-worker/handler/handler.go

@@ -8,6 +8,7 @@ import (
 
 	"github.com/nats-io/go-nats-streaming"
 	"github.com/openfaas/faas/gateway/queue"
+	"regexp"
 )
 
 // NatsQueue queue for work
@@ -22,9 +23,11 @@ type NatsConfig interface {
 type DefaultNatsConfig struct {
 }
 
+var supportedCharacters, _ = regexp.Compile("[^a-zA-Z0-9-_]+")
+
 func (DefaultNatsConfig) GetClientID() string {
 	val, _ := os.Hostname()
-	return "faas-publisher-" + val
+	return getClientId(val)
 }
 
 // CreateNatsQueue ready for asynchronous processing
@@ -58,3 +61,7 @@ func (q *NatsQueue) Queue(req *queue.Request) error {
 
 	return err
 }
+
+func getClientId(hostname string) string {
+	return "faas-publisher-" + supportedCharacters.ReplaceAllString(hostname, "_")
+}

gateway/vendor/github.com/openfaas/nats-queue-worker/handler/handler_test.go

@@ -17,3 +17,23 @@ func Test_GetClientID_ContainsHostname(t *testing.T) {
 		t.Fail()
 	}
 }
+
+func TestCreateClientId(t *testing.T) {
+	clientId := getClientId("computer-a")
+	expected := "faas-publisher-computer-a"
+	if clientId != expected {
+		t.Logf("Expected client id `%s` actual `%s`\n", expected, clientId)
+		t.Fail()
+	}
+}
+
+func TestCreateClientIdWhenHostHasUnsupportedCharacters(t *testing.T) {
+	clientId := getClientId("computer-a.acme.com")
+	expected := "faas-publisher-computer-a_acme_com"
+	if clientId != expected {
+		t.Logf("Expected client id `%s` actual `%s`\n", expected, clientId)
+		t.Fail()
+	}
+}
+
+