Merge cache and informers into a single type.

Author: pwittrock

pkg/cache/cache.go

@@ -33,16 +33,16 @@ import (
 
 var log = logf.KBLog.WithName("object-cache")
 
-// Cache implements ReadInterface by reading objects from a cache populated by Informers
+// Cache implements ReadInterface by reading objects from a cache populated by InformersMap
 type Cache interface {
 	// Cache implements the client ReadInterface
 	client.ReadInterface
 
-	// Cache implements Informers
+	// Cache implements InformersMap
 	Informers
 }
 
-// Informers knows how to create or fetch informers for different group-version-kinds.
+// InformersMap knows how to create or fetch informers for different group-version-kinds.
 // It's safe to call GetInformer from multiple threads.
 type Informers interface {
 	// GetInformer fetches or constructs an informer for the given object that corresponds to a single
@@ -64,7 +64,7 @@ type Informers interface {
 	IndexField(obj runtime.Object, field string, extractValue client.IndexerFunc) error
 }
 
-// Options are the optional arguments for creating a new Informers object
+// Options are the optional arguments for creating a new InformersMap object
 type Options struct {
 	// Scheme is the scheme to use for mapping objects to GroupVersionKinds
 	Scheme *runtime.Scheme
@@ -76,14 +76,13 @@ type Options struct {
 	Resync *time.Duration
 }
 
-var _ Informers = &cache{}
-var _ client.ReadInterface = &cache{}
-var _ Cache = &cache{}
+var _ Informers = &informerCache{}
+var _ client.ReadInterface = &informerCache{}
+var _ Cache = &informerCache{}
 
-// cache is a Kubernetes Object cache populated from Informers.  cache wraps a CacheProvider and InformerProvider.
-type cache struct {
-	*internal.CacheProvider
-	*internal.InformerProvider
+// cache is a Kubernetes Object cache populated from InformersMap.  cache wraps a CacheProvider and InformersMap.
+type informerCache struct {
+	*internal.InformersMap
 }
 
 // New initializes and returns a new Cache
@@ -109,9 +108,6 @@ func New(config *rest.Config, opts Options) (Cache, error) {
 		opts.Resync = &r
 	}
 
-	cp := internal.NewCacheProvider()
-	ip := internal.NewInformerProvider(config, opts.Scheme, opts.Mapper, *opts.Resync, cp)
-	cp.SetInformerProvider(ip)
-	c := &cache{InformerProvider: ip, CacheProvider: cp}
-	return c, nil
+	im := internal.NewInformers(config, opts.Scheme, opts.Mapper, *opts.Resync)
+	return &informerCache{InformersMap: im}, nil
 }

pkg/cache/informers.go

@@ -0,0 +1,108 @@
+/*
+Copyright 2018 The Kubernetes 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 cache
+
+import (
+	"fmt"
+
+	"github.com/kubernetes-sigs/controller-runtime/pkg/cache/internal"
+	"github.com/kubernetes-sigs/controller-runtime/pkg/client"
+	"github.com/kubernetes-sigs/controller-runtime/pkg/client/apiutil"
+	apimeta "k8s.io/apimachinery/pkg/api/meta"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	"k8s.io/client-go/tools/cache"
+)
+
+// GetInformerForKind returns the informer for the GroupVersionKind
+func (ip *informerCache) GetInformerForKind(gvk schema.GroupVersionKind) (cache.SharedIndexInformer, error) {
+	// Map the gvk to an object
+	obj, err := ip.Scheme.New(gvk)
+	if err != nil {
+		return nil, err
+	}
+	i, err := ip.InformersMap.Get(gvk, obj)
+	if err != nil {
+		return nil, err
+	}
+	return i.Informer, err
+}
+
+// GetInformer returns the informer for the obj
+func (ip *informerCache) GetInformer(obj runtime.Object) (cache.SharedIndexInformer, error) {
+	gvk, err := apiutil.GVKForObject(obj, ip.Scheme)
+	if err != nil {
+		return nil, err
+	}
+	i, err := ip.InformersMap.Get(gvk, obj)
+	if err != nil {
+		return nil, err
+	}
+	return i.Informer, err
+}
+
+// IndexField adds an indexer to the underlying cache, using extraction function to get
+// value(s) from the given field.  This index can then be used by passing a field selector
+// to List. For one-to-one compatibility with "normal" field selectors, only return one value.
+// The values may be anything.  They will automatically be prefixed with the namespace of the
+// given object, if present.  The objects passed are guaranteed to be objects of the correct type.
+func (ip *informerCache) IndexField(obj runtime.Object, field string, extractValue client.IndexerFunc) error {
+	informer, err := ip.GetInformer(obj)
+	if err != nil {
+		return err
+	}
+	return indexByField(informer.GetIndexer(), field, extractValue)
+}
+
+func indexByField(indexer cache.Indexer, field string, extractor client.IndexerFunc) error {
+	indexFunc := func(objRaw interface{}) ([]string, error) {
+		// TODO(directxman12): check if this is the correct type?
+		obj, isObj := objRaw.(runtime.Object)
+		if !isObj {
+			return nil, fmt.Errorf("object of type %T is not an Object", objRaw)
+		}
+		meta, err := apimeta.Accessor(obj)
+		if err != nil {
+			return nil, err
+		}
+		ns := meta.GetNamespace()
+
+		rawVals := extractor(obj)
+		var vals []string
+		if ns == "" {
+			// if we're not doubling the keys for the namespaced case, just re-use what was returned to us
+			vals = rawVals
+		} else {
+			// if we need to add non-namespaced versions too, double the length
+			vals = make([]string, len(rawVals)*2)
+		}
+		for i, rawVal := range rawVals {
+			// save a namespaced variant, so that we can ask
+			// "what are all the object matching a given index *in a given namespace*"
+			vals[i] = internal.KeyToNamespacedKey(ns, rawVal)
+			if ns != "" {
+				// if we have a namespace, also inject a special index key for listing
+				// regardless of the object namespace
+				vals[i+len(rawVals)] = internal.KeyToNamespacedKey("", rawVal)
+			}
+		}
+
+		return vals, nil
+	}
+
+	return indexer.AddIndexers(cache.Indexers{internal.FieldIndexName(field): indexFunc})
+}