Move packages to proejct/pkg to follow go project folder structure convention (#1190)

pkg/router/functionServiceMap.go

@@ -0,0 +1,84 @@
+/*
+Copyright 2016 The Fission Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package router
+
+import (
+	"net/url"
+	"time"
+
+	"go.uber.org/zap"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+
+	"github.com/fission/fission/pkg/cache"
+)
+
+type (
+	functionServiceMap struct {
+		logger *zap.Logger
+		cache  *cache.Cache // map[metadataKey]*url.URL
+	}
+
+	// metav1.ObjectMeta is not hashable, so we make a hashable copy
+	// of the subset of its fields that are identifiable.
+	metadataKey struct {
+		Name            string
+		Namespace       string
+		ResourceVersion string
+	}
+)
+
+func makeFunctionServiceMap(logger *zap.Logger, expiry time.Duration) *functionServiceMap {
+	return &functionServiceMap{
+		logger: logger.Named("function_service_map"),
+		cache:  cache.MakeCache(expiry, 0),
+	}
+}
+
+func keyFromMetadata(m *metav1.ObjectMeta) *metadataKey {
+	return &metadataKey{
+		Name:            m.Name,
+		Namespace:       m.Namespace,
+		ResourceVersion: m.ResourceVersion,
+	}
+}
+
+func (fmap *functionServiceMap) lookup(f *metav1.ObjectMeta) (*url.URL, error) {
+	mk := keyFromMetadata(f)
+	item, err := fmap.cache.Get(*mk)
+	if err != nil {
+		return nil, err
+	}
+	u := item.(*url.URL)
+	return u, nil
+}
+
+func (fmap *functionServiceMap) assign(f *metav1.ObjectMeta, serviceUrl *url.URL) {
+	mk := keyFromMetadata(f)
+	err, old := fmap.cache.Set(*mk, serviceUrl)
+	if err != nil {
+		if *serviceUrl == *(old.(*url.URL)) {
+			return
+		}
+		fmap.logger.Error("error caching service url for function with a different value", zap.Error(err))
+		// ignore error
+	}
+}
+
+func (fmap *functionServiceMap) remove(f *metav1.ObjectMeta) error {
+	mk := keyFromMetadata(f)
+	return fmap.cache.Delete(*mk)
+}