Publish to multiple topics

Enables publishing to various topics according to annotations
on the functions. The function cache is moved up one level so
that it can be shared between the scale from zero code and the
queue proxy.

Unit tests added for new internal methods.

Tested e2e with arkade and the newest queue-worker and RC
gateway image with two queues and an annotation on one of the
functions of com.openfaas.queue. It worked as expected including
with multiple namespace support.

Signed-off-by: Alex Ellis (OpenFaaS Ltd) <alexellis2@gmail.com>

gateway/Dockerfile

@@ -28,6 +28,7 @@ COPY queue          queue
 COPY plugin         plugin
 COPY version        version
 COPY scaling        scaling
+COPY pkg            pkg
 COPY main.go      .
 
 # Run a gofmt and exclude all vendored code.

gateway/Dockerfile.arm64

@@ -25,6 +25,7 @@ COPY queue          queue
 COPY plugin         plugin
 COPY version        version
 COPY scaling        scaling
+COPY pkg            pkg
 COPY main.go      .
 
 # Run a gofmt and exclude all vendored code.

gateway/Dockerfile.armhf

@@ -25,6 +25,7 @@ COPY queue          queue
 COPY plugin         plugin
 COPY version        version
 COPY scaling        scaling
+COPY pkg            pkg
 COPY main.go      .
 
 # Run a gofmt and exclude all vendored code.

gateway/Gopkg.lock

@@ -101,12 +101,12 @@
   version = "v0.6.0"
 
 [[projects]]
-  digest = "1:340f4e2e095ead4e0a15b4646da3e4533f8b6520e3a382eaf586e8166f3bbcb5"
+  digest = "1:437d6b220b852cd40c465c4eaf01ec26fd1dfdfb9c8c67933a256d0c97fdabb8"
   name = "github.com/openfaas/faas"
   packages = ["gateway/queue"]
   pruneopts = "UT"
-  revision = "bfa869ec8c0c04c26c5b0ed434bc367e712dcaef"
-  version = "0.10.2"
+  revision = "a7c6c39200782ea2e1a1b005d56e3edd51e761a7"
+  version = "0.18.16"
 
 [[projects]]
   digest = "1:4a97aa8ada0b2f865ca69a3a3bc0a2524c24f31c578c995d5c52cecb6913a9dc"
@@ -120,15 +120,15 @@
   version = "0.12.0"
 
 [[projects]]
-  digest = "1:1cf86a1a93c110ebcf836468bd917e8c116d6d2fc7612829c15e946b02dbf864"
+  digest = "1:e40ae4e58551013ed5ad4085b337718c9fba314372c0751713ed9fe8082a323d"
   name = "github.com/openfaas/nats-queue-worker"
   packages = [
     "handler",
     "nats",
   ]
   pruneopts = "UT"
-  revision = "a1835cb71db56e6b814b91df027acf62425a76ad"
-  version = "0.10.0"
+  revision = "1f4e16e1f7afe1fbd464fcaa8a7dabaa3e4ef0bb"
+  version = "0.10.1"
 
 [[projects]]
   digest = "1:eb04f69c8991e52eff33c428bd729e04208bf03235be88e4df0d88497c6861b9"

gateway/Gopkg.toml

@@ -12,7 +12,7 @@
 
 [[constraint]]
   name = "github.com/openfaas/nats-queue-worker"
-  version = "0.10.0"
+  version = "0.10.1"
 
 [[constraint]]
   name = "github.com/prometheus/client_golang"

gateway/handlers/forwarding_proxy.go

@@ -14,6 +14,7 @@ import (
 	"strings"
 	"time"
 
+	"github.com/openfaas/faas/gateway/pkg/middleware"
 	"github.com/openfaas/faas/gateway/types"
 )
 
@@ -43,7 +44,7 @@ func MakeForwardingProxyHandler(proxy *types.HTTPClientReverseProxy,
 	notifiers []HTTPNotifier,
 	baseURLResolver BaseURLResolver,
 	urlPathTransformer URLPathTransformer,
-	serviceAuthInjector AuthInjector) http.HandlerFunc {
+	serviceAuthInjector middleware.AuthInjector) http.HandlerFunc {
 
 	writeRequestURI := false
 	if _, exists := os.LookupEnv("write_request_uri"); exists {
@@ -108,7 +109,7 @@ func forwardRequest(w http.ResponseWriter,
 	requestURL string,
 	timeout time.Duration,
 	writeRequestURI bool,
-	serviceAuthInjector AuthInjector) (int, error) {
+	serviceAuthInjector middleware.AuthInjector) (int, error) {
 
 	upstreamReq := buildUpstreamRequest(r, baseURL, requestURL)
 	if upstreamReq.Body != nil {

gateway/handlers/queue_proxy.go

@@ -6,16 +6,19 @@ package handlers
 import (
 	"fmt"
 	"io/ioutil"
+	"log"
 	"net/http"
 	"net/url"
+	"strings"
 
 	"github.com/gorilla/mux"
 	"github.com/openfaas/faas/gateway/metrics"
 	"github.com/openfaas/faas/gateway/queue"
+	"github.com/openfaas/faas/gateway/scaling"
 )
 
 // MakeQueuedProxy accepts work onto a queue
-func MakeQueuedProxy(metrics metrics.MetricOptions, wildcard bool, canQueueRequests queue.CanQueueRequests, pathTransformer URLPathTransformer) http.HandlerFunc {
+func MakeQueuedProxy(metrics metrics.MetricOptions, wildcard bool, queuer queue.RequestQueuer, pathTransformer URLPathTransformer, defaultNS string, functionCacher scaling.FunctionCacher, serviceQuery scaling.ServiceQuery) http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
 		if r.Body != nil {
 			defer r.Body.Close()
@@ -24,29 +27,20 @@ func MakeQueuedProxy(metrics metrics.MetricOptions, wildcard bool, canQueueReque
 		body, err := ioutil.ReadAll(r.Body)
 
 		if err != nil {
-			w.WriteHeader(http.StatusBadRequest)
+			http.Error(w, err.Error(), http.StatusBadRequest)
+			return
+		}
 
-			w.Write([]byte(err.Error()))
+		callbackURL, err := getCallbackURLHeader(r.Header)
+		if err != nil {
+			http.Error(w, err.Error(), http.StatusBadRequest)
 			return
 		}
 
 		vars := mux.Vars(r)
 		name := vars["name"]
 
-		callbackURLHeader := r.Header.Get("X-Callback-Url")
-		var callbackURL *url.URL
-
-		if len(callbackURLHeader) > 0 {
-			urlVal, urlErr := url.Parse(callbackURLHeader)
-			if urlErr != nil {
-				w.WriteHeader(http.StatusBadRequest)
-
-				w.Write([]byte(urlErr.Error()))
-				return
-			}
-
-			callbackURL = urlVal
-		}
+		queueName, err := getQueueName(name, functionCacher, serviceQuery)
 
 		req := &queue.Request{
 			Function:    name,
@@ -57,15 +51,69 @@ func MakeQueuedProxy(metrics metrics.MetricOptions, wildcard bool, canQueueReque
 			Header:      r.Header,
 			Host:        r.Host,
 			CallbackURL: callbackURL,
+			QueueName:   queueName,
 		}
 
-		if err = canQueueRequests.Queue(req); err != nil {
-			w.WriteHeader(http.StatusInternalServerError)
-			w.Write([]byte(err.Error()))
-			fmt.Println(err)
+		if len(queueName) > 0 {
+			log.Printf("Queueing %s to: %s\n", name, queueName)
+		}
+
+		if err = queuer.Queue(req); err != nil {
+			fmt.Printf("Queue error: %v\n", err)
+			http.Error(w, err.Error(), http.StatusInternalServerError)
 			return
 		}
 
 		w.WriteHeader(http.StatusAccepted)
 	}
 }
+
+func getQueueName(name string, cache scaling.FunctionCacher, serviceQuery scaling.ServiceQuery) (queueName string, err error) {
+	fn, ns := getNameParts(name)
+
+	query, hit := cache.Get(fn, ns)
+	if !hit {
+		queryResponse, err := serviceQuery.GetReplicas(fn, ns)
+		if err != nil {
+			return "", err
+		}
+		cache.Set(fn, ns, queryResponse)
+	}
+
+	query, _ = cache.Get(fn, ns)
+
+	queueName = ""
+	if query.Annotations != nil {
+		if v := (*query.Annotations)["com.openfaas.queue"]; len(v) > 0 {
+			queueName = v
+		}
+	}
+	return queueName, err
+}
+
+func getCallbackURLHeader(header http.Header) (*url.URL, error) {
+	value := header.Get("X-Callback-Url")
+	var callbackURL *url.URL
+
+	if len(value) > 0 {
+		urlVal, err := url.Parse(value)
+		if err != nil {
+			return callbackURL, err
+		}
+
+		callbackURL = urlVal
+	}
+
+	return callbackURL, nil
+}
+
+func getNameParts(name string) (fn, ns string) {
+	fn = name
+	ns = ""
+
+	if index := strings.LastIndex(name, "."); index > 0 {
+		fn = name[:index]
+		ns = name[index+1:]
+	}
+	return fn, ns
+}

gateway/handlers/queue_proxy_test.go

@@ -0,0 +1,74 @@
+// Copyright (c) Alex Ellis 2017. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+package handlers
+
+import (
+	"net/http"
+	"testing"
+)
+
+func Test_getNameParts(t *testing.T) {
+	fn, ns := getNameParts("figlet.openfaas-fn")
+	wantFn := "figlet"
+	wantNs := "openfaas-fn"
+
+	if fn != wantFn {
+		t.Fatalf("want %s, got %s", wantFn, fn)
+	}
+	if ns != wantNs {
+		t.Fatalf("want %s, got %s", wantNs, ns)
+	}
+}
+
+func Test_getNamePartsDualDot(t *testing.T) {
+	fn, ns := getNameParts("dev.figlet.openfaas-fn")
+	wantFn := "dev.figlet"
+	wantNs := "openfaas-fn"
+
+	if fn != wantFn {
+		t.Fatalf("want %s, got %s", wantFn, fn)
+	}
+	if ns != wantNs {
+		t.Fatalf("want %s, got %s", wantNs, ns)
+	}
+}
+
+func Test_getNameParts_NoNs(t *testing.T) {
+	fn, ns := getNameParts("figlet")
+	wantFn := "figlet"
+	wantNs := ""
+
+	if fn != wantFn {
+		t.Fatalf("want %s, got %s", wantFn, fn)
+	}
+	if ns != wantNs {
+		t.Fatalf("want %s, got %s", wantNs, ns)
+	}
+}
+
+func Test_getCallbackURLHeader(t *testing.T) {
+	want := "http://localhost:8080"
+	header := http.Header{}
+	header.Add("X-Callback-Url", want)
+
+	uri, err := getCallbackURLHeader(header)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if uri.String() != want {
+		t.Fatalf("want %s, but got %s", want, uri.String())
+	}
+}
+
+func Test_getCallbackURLHeader_ParseFails(t *testing.T) {
+	want := "ht tp://foo.com"
+	header := http.Header{}
+	header.Add("X-Callback-Url", want)
+
+	_, err := getCallbackURLHeader(header)
+	if err == nil {
+		t.Fatal("wanted a parsing error.")
+	}
+}

gateway/handlers/scaling.go

@@ -24,9 +24,7 @@ func getNamespace(defaultNamespace, fullName string) (string, string) {
 // be called. If the function is not ready after the configured
 // amount of attempts / queries then next will not be invoked and a status
 // will be returned to the client.
-func MakeScalingHandler(next http.HandlerFunc, config scaling.ScalingConfig, defaultNamespace string) http.HandlerFunc {
-
-	scaler := scaling.NewFunctionScaler(config)
+func MakeScalingHandler(next http.HandlerFunc, scaler scaling.FunctionScaler, config scaling.ScalingConfig, defaultNamespace string) http.HandlerFunc {
 
 	return func(w http.ResponseWriter, r *http.Request) {
 

gateway/main.go

@@ -13,6 +13,7 @@ import (
 	"github.com/openfaas/faas-provider/auth"
 	"github.com/openfaas/faas/gateway/handlers"
 	"github.com/openfaas/faas/gateway/metrics"
+	"github.com/openfaas/faas/gateway/pkg/middleware"
 	"github.com/openfaas/faas/gateway/plugin"
 	"github.com/openfaas/faas/gateway/scaling"
 	"github.com/openfaas/faas/gateway/types"
@@ -60,6 +61,9 @@ func main() {
 
 	servicePollInterval := time.Second * 5
 
+	metadataQuery := metrics.NewMetadataQuery(credentials)
+	fmt.Println(metadataQuery)
+
 	metricsOptions := metrics.BuildMetricsOptions()
 	exporter := metrics.NewExporter(metricsOptions, credentials)
 	exporter.StartServiceWatcher(*config.FunctionsProviderURL, metricsOptions, "func", servicePollInterval)
@@ -100,10 +104,10 @@ func main() {
 		functionURLTransformer = nilURLTransformer
 	}
 
-	var serviceAuthInjector handlers.AuthInjector
+	var serviceAuthInjector middleware.AuthInjector
 
 	if config.UseBasicAuth {
-		serviceAuthInjector = &handlers.BasicAuthInjector{Credentials: credentials}
+		serviceAuthInjector = &middleware.BasicAuthInjector{Credentials: credentials}
 	}
 
 	decorateExternalAuth := handlers.MakeExternalAuthHandler
@@ -129,6 +133,21 @@ func main() {
 
 	faasHandlers.LogProxyHandler = handlers.NewLogHandlerFunc(*config.LogsProviderURL, config.WriteTimeout)
 
+	scalingConfig := scaling.ScalingConfig{
+		MaxPollCount:         uint(1000),
+		SetScaleRetries:      uint(20),
+		FunctionPollInterval: time.Millisecond * 50,
+		CacheExpiry:          time.Second * 5, // freshness of replica values before going stale
+		ServiceQuery:         externalServiceQuery,
+	}
+
+	functionProxy := faasHandlers.Proxy
+	if config.ScaleFromZero {
+		scalingFunctionCache := scaling.NewFunctionCache(scalingConfig.CacheExpiry)
+		scaler := scaling.NewFunctionScaler(scalingConfig, scalingFunctionCache)
+		functionProxy = handlers.MakeScalingHandler(faasHandlers.Proxy, scaler, scalingConfig, config.Namespace)
+	}
+
 	if config.UseNATS() {
 		log.Println("Async enabled: Using NATS Streaming.")
 		maxReconnect := 60
@@ -141,8 +160,9 @@ func main() {
 			log.Fatalln(queueErr)
 		}
 
+		queueFunctionCache := scaling.NewFunctionCache(scalingConfig.CacheExpiry)
 		faasHandlers.QueuedProxy = handlers.MakeNotifierWrapper(
-			handlers.MakeCallIDMiddleware(handlers.MakeQueuedProxy(metricsOptions, true, natsQueue, trimURLTransformer)),
+			handlers.MakeCallIDMiddleware(handlers.MakeQueuedProxy(metricsOptions, true, natsQueue, trimURLTransformer, config.Namespace, queueFunctionCache, externalServiceQuery)),
 			forwardingNotifiers,
 		)
 
@@ -188,20 +208,6 @@ func main() {
 	r := mux.NewRouter()
 	// max wait time to start a function = maxPollCount * functionPollInterval
 
-	functionProxy := faasHandlers.Proxy
-
-	if config.ScaleFromZero {
-		scalingConfig := scaling.ScalingConfig{
-			MaxPollCount:         uint(1000),
-			SetScaleRetries:      uint(20),
-			FunctionPollInterval: time.Millisecond * 50,
-			CacheExpiry:          time.Second * 5, // freshness of replica values before going stale
-			ServiceQuery:         externalServiceQuery,
-		}
-
-		functionProxy = handlers.MakeScalingHandler(faasHandlers.Proxy, scalingConfig, config.Namespace)
-	}
-
 	r.HandleFunc("/function/{name:["+NameExpression+"]+}", functionProxy)
 	r.HandleFunc("/function/{name:["+NameExpression+"]+}/", functionProxy)
 	r.HandleFunc("/function/{name:["+NameExpression+"]+}/{params:.*}", functionProxy)

gateway/metrics/metadata_query.go

@@ -0,0 +1,11 @@
+package metrics
+
+import "github.com/openfaas/faas-provider/auth"
+
+type MetadataQuery struct {
+	Credentials *auth.BasicAuthCredentials
+}
+
+func NewMetadataQuery(credentials *auth.BasicAuthCredentials) *MetadataQuery {
+	return &MetadataQuery{Credentials: credentials}
+}

gateway/pkg/middleware/basic_auth_injector.go

@@ -1,7 +1,7 @@
 // Copyright (c) OpenFaaS Author(s). All rights reserved.
 // Licensed under the MIT license. See LICENSE file in the project root for full license information.
 
-package handlers
+package middleware
 
 import (
 	"net/http"

gateway/pkg/middleware/basic_auth_injector_test.go

@@ -1,7 +1,7 @@
 // Copyright (c) OpenFaaS Author(s). All rights reserved.
 // Licensed under the MIT license. See LICENSE file in the project root for full license information.
 
-package handlers
+package middleware
 
 import (
 	"net/http"

gateway/pkg/middleware/serviceauthinjector.go

@@ -1,4 +1,4 @@
-package handlers
+package middleware
 
 import "net/http"
 

gateway/plugin/external.go

@@ -16,12 +16,26 @@ import (
 	"time"
 
 	types "github.com/openfaas/faas-provider/types"
-	"github.com/openfaas/faas/gateway/handlers"
+	middleware "github.com/openfaas/faas/gateway/pkg/middleware"
 	"github.com/openfaas/faas/gateway/scaling"
 )
 
+// ExternalServiceQuery proxies service queries to external plugin via HTTP
+type ExternalServiceQuery struct {
+	URL          url.URL
+	ProxyClient  http.Client
+	AuthInjector middleware.AuthInjector
+}
+
+// ScaleServiceRequest request scaling of replica
+type ScaleServiceRequest struct {
+	ServiceName      string `json:"serviceName"`
+	ServiceNamespace string `json:"serviceNamespace"`
+	Replicas         uint64 `json:"replicas"`
+}
+
 // NewExternalServiceQuery proxies service queries to external plugin via HTTP
-func NewExternalServiceQuery(externalURL url.URL, authInjector handlers.AuthInjector) scaling.ServiceQuery {
+func NewExternalServiceQuery(externalURL url.URL, authInjector middleware.AuthInjector) scaling.ServiceQuery {
 	timeout := 3 * time.Second
 
 	proxyClient := http.Client{
@@ -45,20 +59,6 @@ func NewExternalServiceQuery(externalURL url.URL, authInjector handlers.AuthInje
 	}
 }
 
-// ExternalServiceQuery proxies service queries to external plugin via HTTP
-type ExternalServiceQuery struct {
-	URL          url.URL
-	ProxyClient  http.Client
-	AuthInjector handlers.AuthInjector
-}
-
-// ScaleServiceRequest request scaling of replica
-type ScaleServiceRequest struct {
-	ServiceName      string `json:"serviceName"`
-	ServiceNamespace string `json:"serviceNamespace"`
-	Replicas         uint64 `json:"replicas"`
-}
-
 // GetReplicas replica count for function
 func (s ExternalServiceQuery) GetReplicas(serviceName, serviceNamespace string) (scaling.ServiceQueryResponse, error) {
 	start := time.Now()
@@ -126,6 +126,7 @@ func (s ExternalServiceQuery) GetReplicas(serviceName, serviceNamespace string)
 		MinReplicas:       minReplicas,
 		ScalingFactor:     scalingFactor,
 		AvailableReplicas: availableReplicas,
+		Annotations:       function.Annotations,
 	}, err
 }
 

gateway/plugin/external_test.go

@@ -7,7 +7,7 @@ import (
 	"strings"
 	"testing"
 
-	"github.com/openfaas/faas/gateway/handlers"
+	middleware "github.com/openfaas/faas/gateway/pkg/middleware"
 	"github.com/openfaas/faas/gateway/scaling"
 )
 
@@ -47,7 +47,7 @@ func TestGetReplicasNonExistentFn(t *testing.T) {
 		}))
 	defer testServer.Close()
 
-	var injector handlers.AuthInjector
+	var injector middleware.AuthInjector
 	url, _ := url.Parse(testServer.URL + "/")
 
 	esq := NewExternalServiceQuery(*url, injector)
@@ -77,7 +77,7 @@ func TestGetReplicasExistentFn(t *testing.T) {
 		AvailableReplicas: 0,
 	}
 
-	var injector handlers.AuthInjector
+	var injector middleware.AuthInjector
 	url, _ := url.Parse(testServer.URL + "/")
 
 	esq := NewExternalServiceQuery(*url, injector)
@@ -102,7 +102,7 @@ func TestSetReplicasNonExistentFn(t *testing.T) {
 		}))
 	defer testServer.Close()
 
-	var injector handlers.AuthInjector
+	var injector middleware.AuthInjector
 	url, _ := url.Parse(testServer.URL + "/")
 	esq := NewExternalServiceQuery(*url, injector)
 
@@ -124,7 +124,7 @@ func TestSetReplicasExistentFn(t *testing.T) {
 		}))
 	defer testServer.Close()
 
-	var injector handlers.AuthInjector
+	var injector middleware.AuthInjector
 
 	url, _ := url.Parse(testServer.URL + "/")
 	esq := NewExternalServiceQuery(*url, injector)

gateway/queue/types.go

@@ -43,8 +43,3 @@ type Request struct {
 type RequestQueuer interface {
 	Queue(req *Request) error
 }
-
-// CanQueueRequests can take on asynchronous requests
-type CanQueueRequests interface {
-	Queue(req *Request) error
-}

gateway/scaling/function_cache.go

@@ -8,17 +8,10 @@ import (
 	"time"
 )
 
-// FunctionMeta holds the last refresh and any other
-// meta-data needed for caching.
-type FunctionMeta struct {
-	LastRefresh          time.Time
-	ServiceQueryResponse ServiceQueryResponse
-}
-
-// Expired find out whether the cache item has expired with
-// the given expiry duration from when it was stored.
-func (fm *FunctionMeta) Expired(expiry time.Duration) bool {
-	return time.Now().After(fm.LastRefresh.Add(expiry))
+// FunctionCacher queries functions and caches the results
+type FunctionCacher interface {
+	Set(functionName, namespace string, serviceQueryResponse ServiceQueryResponse)
+	Get(functionName, namespace string) (ServiceQueryResponse, bool)
 }
 
 // FunctionCache provides a cache of Function replica counts
@@ -28,8 +21,16 @@ type FunctionCache struct {
 	Sync   sync.RWMutex
 }
 
+// NewFunctionCache creates a function cache to query function metadata
+func NewFunctionCache(cacheExpiry time.Duration) FunctionCacher {
+	return &FunctionCache{
+		Cache:  make(map[string]*FunctionMeta),
+		Expiry: cacheExpiry,
+	}
+}
+
 // Set replica count for functionName
-func (fc *FunctionCache) Set(functionName, namespace string, serviceQueryResponse ServiceQueryResponse) {
+func (fc *FunctionCache) Set(functionName, namespace string, queryRes ServiceQueryResponse) {
 	fc.Sync.Lock()
 	defer fc.Sync.Unlock()
 
@@ -38,14 +39,12 @@ func (fc *FunctionCache) Set(functionName, namespace string, serviceQueryRespons
 	}
 
 	fc.Cache[functionName+"."+namespace].LastRefresh = time.Now()
-	fc.Cache[functionName+"."+namespace].ServiceQueryResponse = serviceQueryResponse
-	// entry.LastRefresh = time.Now()
-	// entry.ServiceQueryResponse = serviceQueryResponse
+	fc.Cache[functionName+"."+namespace].ServiceQueryResponse = queryRes
 }
 
 // Get replica count for functionName
 func (fc *FunctionCache) Get(functionName, namespace string) (ServiceQueryResponse, bool) {
-	replicas := ServiceQueryResponse{
+	queryRes := ServiceQueryResponse{
 		AvailableReplicas: 0,
 	}
 
@@ -54,9 +53,9 @@ func (fc *FunctionCache) Get(functionName, namespace string) (ServiceQueryRespon
 	defer fc.Sync.RUnlock()
 
 	if val, exists := fc.Cache[functionName+"."+namespace]; exists {
-		replicas = val.ServiceQueryResponse
+		queryRes = val.ServiceQueryResponse
 		hit = !val.Expired(fc.Expiry)
 	}
 
-	return replicas, hit
+	return queryRes, hit
 }

gateway/scaling/function_meta.go

@@ -0,0 +1,21 @@
+// Copyright (c) OpenFaaS Author(s). All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+package scaling
+
+import (
+	"time"
+)
+
+// FunctionMeta holds the last refresh and any other
+// meta-data needed for caching.
+type FunctionMeta struct {
+	LastRefresh          time.Time
+	ServiceQueryResponse ServiceQueryResponse
+}
+
+// Expired find out whether the cache item has expired with
+// the given expiry duration from when it was stored.
+func (fm *FunctionMeta) Expired(expiry time.Duration) bool {
+	return time.Now().After(fm.LastRefresh.Add(expiry))
+}

gateway/scaling/function_scaler.go

@@ -8,21 +8,16 @@ import (
 
 // NewFunctionScaler create a new scaler with the specified
 // ScalingConfig
-func NewFunctionScaler(config ScalingConfig) FunctionScaler {
-	cache := FunctionCache{
-		Cache:  make(map[string]*FunctionMeta),
-		Expiry: config.CacheExpiry,
-	}
-
+func NewFunctionScaler(config ScalingConfig, functionCacher FunctionCacher) FunctionScaler {
 	return FunctionScaler{
-		Cache:  &cache,
+		Cache:  functionCacher,
 		Config: config,
 	}
 }
 
 // FunctionScaler scales from zero
 type FunctionScaler struct {
-	Cache  *FunctionCache
+	Cache  FunctionCacher
 	Config ScalingConfig
 }
 

gateway/scaling/service_query.go

@@ -16,4 +16,5 @@ type ServiceQueryResponse struct {
 	MinReplicas       uint64
 	ScalingFactor     uint64
 	AvailableReplicas uint64
+	Annotations       *map[string]string
 }

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

@@ -44,7 +44,12 @@ func (q *NATSQueue) Queue(req *queue.Request) error {
 	nc := q.nc
 	q.ncMutex.RUnlock()
 
-	return nc.Publish(q.Topic, out)
+	queueName := q.Topic
+	if len(req.QueueName) > 0 {
+		queueName = req.QueueName
+	}
+
+	return nc.Publish(queueName, out)
 }
 
 func (q *NATSQueue) connect() error {