Canary deployments for fission functions. (#892)

canaryconfigmgr/canaryConfigCache.go

@@ -0,0 +1,72 @@
+/*
+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 canaryconfigmgr
+
+import (
+	"context"
+
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+
+	"github.com/fission/fission/cache"
+)
+
+type (
+	canaryConfigCancelFuncMap struct {
+		cache *cache.Cache // map[metadataKey]*context.Context
+	}
+
+	// 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
+	}
+)
+
+func makecanaryConfigCancelFuncMap() *canaryConfigCancelFuncMap {
+	return &canaryConfigCancelFuncMap{
+		cache: cache.MakeCache(0, 0),
+	}
+}
+
+func keyFromMetadata(m *metav1.ObjectMeta) metadataKey {
+	return metadataKey{
+		Name:      m.Name,
+		Namespace: m.Namespace,
+	}
+}
+
+func (cancelFuncMap *canaryConfigCancelFuncMap) lookup(f *metav1.ObjectMeta) (*context.CancelFunc, error) {
+	mk := keyFromMetadata(f)
+	item, err := cancelFuncMap.cache.Get(mk)
+	if err != nil {
+		return nil, err
+	}
+	cancelFunc := item.(*context.CancelFunc)
+	return cancelFunc, nil
+}
+
+func (cancelFuncMap *canaryConfigCancelFuncMap) assign(f *metav1.ObjectMeta, cancelFunc *context.CancelFunc) error {
+	mk := keyFromMetadata(f)
+	err, _ := cancelFuncMap.cache.Set(mk, cancelFunc)
+	return err
+}
+
+func (cancelFuncMap *canaryConfigCancelFuncMap) remove(f *metav1.ObjectMeta) error {
+	mk := keyFromMetadata(f)
+	return cancelFuncMap.cache.Delete(mk)
+}