Non Watched Namespace Labeled selectors

README.md

@@ -1,6 +1,10 @@
 # solo-kit
 A collection of code generation and libraries to for API development.
 
+### Testing
+To generate tests set `SkipGeneratedTests` to false in the `generate.go` file. This will use the test templates
+to generate the code for the tests. Such as files like `pkg/code-generator/codegen/templates/snapshot_emitter_test_template.go`
+
 ### Description:
 - Define your declarative API in `.proto` files
 - APIs are defined by top-level protobuf messages in `.proto` files

changelog/v0.30.3/namespace-selectors.yaml

@@ -0,0 +1,9 @@
+changelog:
+  - type: NEW_FEATURE
+    issueLink: https://github.com/solo-io/gloo/issues/5868 
+    description: |
+      Added the ability to watch namespaces given be Expression Selectors in the Watch Opts
+      Watched Namespaces work as normally. When Expression Selectors the snapshot
+      emitter will watch, in addition to the watched namespaces, namespaces that
+      are labeled and meet the criteria of the Expression Selector. All resource 
+      clients will watch these namespaces, if set.

pkg/api/external/kubernetes/namespace/resource_client.go

@@ -16,7 +16,6 @@ import (
 	kubev1 "k8s.io/api/core/v1"
 	apierrors "k8s.io/apimachinery/pkg/api/errors"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
-	"k8s.io/apimachinery/pkg/labels"
 	"k8s.io/client-go/kubernetes"
 )
 
@@ -144,7 +143,11 @@ func (rc *namespaceResourceClient) List(namespace string, opts clients.ListOpts)
 		return nil, eris.New("to list namespaces you must watch all namespaces")
 	}
 
-	namespaceObjList, err := rc.cache.NamespaceLister().List(labels.SelectorFromSet(opts.Selector))
+	listOptions, err := clients.GetLabelSelector(opts)
+	if err != nil {
+		return nil, err
+	}
+	namespaceObjList, err := rc.cache.NamespaceLister().List(listOptions)
 	if err != nil {
 		return nil, eris.Wrapf(err, "listing namespaces level")
 	}

pkg/api/external/kubernetes/namespace/resource_namespace.go

@@ -0,0 +1,183 @@
+package namespace
+
+import (
+	"bytes"
+
+	"github.com/pkg/errors"
+	"github.com/solo-io/solo-kit/pkg/api/v1/clients"
+	"github.com/solo-io/solo-kit/pkg/api/v1/clients/kube/cache"
+	"github.com/solo-io/solo-kit/pkg/api/v1/resources"
+	skkube "github.com/solo-io/solo-kit/pkg/api/v1/resources/common/kubernetes"
+	kubev1 "k8s.io/api/core/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	kubewatch "k8s.io/apimachinery/pkg/watch"
+	"k8s.io/client-go/kubernetes"
+)
+
+var _ resources.ResourceNamespaceLister = &kubeResourceNamespaceLister{}
+var _ resources.ResourceNamespaceLister = &kubeClientResourceNamespaceLister{}
+
+// NewKubeClientCacheResourceNamespaceLister will create a new resource namespace lister that requires the kubernestes
+// client and cache.
+func NewKubeClientCacheResourceNamespaceLister(kube kubernetes.Interface, cache cache.KubeCoreCache) resources.ResourceNamespaceLister {
+	return &kubeResourceNamespaceLister{
+		client: NewNamespaceClient(kube, cache),
+	}
+}
+
+// NewKubeClientResourceNamespaceLister will create a new resource namespace lister that requires the kubernetes client
+// interface.
+func NewKubeClientResourceNamespaceLister(kube kubernetes.Interface) resources.ResourceNamespaceLister {
+	return &kubeClientResourceNamespaceLister{
+		kube: kube,
+	}
+}
+
+type kubeResourceNamespaceLister struct {
+	client skkube.KubeNamespaceClient
+}
+
+// GetResourceNamespaceList is the kubernetes implementation that returns the list of namespaces
+func (kns *kubeResourceNamespaceLister) GetResourceNamespaceList(opts resources.ResourceNamespaceListOptions, filtered resources.ResourceNamespaceList) (resources.ResourceNamespaceList, error) {
+	namespaces, err := kns.client.List(clients.TranslateResourceNamespaceListToListOptions(opts))
+	if err != nil {
+		return nil, err
+	}
+	converted := convertNamespaceListToResourceNamespace(namespaces)
+	return kns.filter(converted, filtered), nil
+}
+
+// GetResourceNamespaceWatch returns a watch for events that occur on kube namespaces returning a list of all the namespaces
+func (kns *kubeResourceNamespaceLister) GetResourceNamespaceWatch(opts resources.ResourceNamespaceWatchOptions, filtered resources.ResourceNamespaceList) (chan resources.ResourceNamespaceList, <-chan error, error) {
+	ctx := opts.Ctx
+	wopts := clients.TranslateResourceNamespaceListToWatchOptions(opts)
+	namespaceChan, errorChan, err := kns.client.Watch(wopts)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	resourceNamespaceChan := make(chan resources.ResourceNamespaceList)
+	go func() {
+		defer close(resourceNamespaceChan)
+		for {
+			select {
+			case namespaceList := <-namespaceChan:
+				select {
+				case resourceNamespaceChan <- kns.filter(convertNamespaceListToResourceNamespace(namespaceList), filtered):
+				case <-ctx.Done():
+					return
+				}
+			case <-ctx.Done():
+				return
+			}
+		}
+	}()
+	return resourceNamespaceChan, errorChan, nil
+}
+
+func (kns *kubeResourceNamespaceLister) filter(namespaces resources.ResourceNamespaceList, filter resources.ResourceNamespaceList) resources.ResourceNamespaceList {
+	filteredList := resources.ResourceNamespaceList{}
+	for _, ns := range namespaces {
+		add := true
+		for _, wns := range filter {
+			if ns.Name == wns.Name {
+				add = false
+				break
+			}
+		}
+		if add {
+			filteredList = append(filteredList, ns)
+		}
+	}
+	return filteredList
+}
+
+func convertNamespaceListToResourceNamespace(namespaces skkube.KubeNamespaceList) resources.ResourceNamespaceList {
+	l := make(resources.ResourceNamespaceList, len(namespaces))
+	for i, ns := range namespaces {
+		l[i] = resources.ResourceNamespace{Name: ns.ObjectMeta.Name}
+	}
+	return l
+}
+
+type kubeClientResourceNamespaceLister struct {
+	kube kubernetes.Interface
+}
+
+// GetResourceNamespaceList is the kubernetes implementation that returns the list of namespaces
+func (client *kubeClientResourceNamespaceLister) GetResourceNamespaceList(opts resources.ResourceNamespaceListOptions, filtered resources.ResourceNamespaceList) (resources.ResourceNamespaceList, error) {
+	excludeNamespaces := client.getExcludeFieldSelector(filtered)
+	namespaceList, err := client.kube.CoreV1().Namespaces().List(opts.Ctx, metav1.ListOptions{FieldSelector: excludeNamespaces, LabelSelector: opts.ExpressionSelector})
+	if err != nil {
+		return nil, err
+	}
+	return convertNamespaceListToResourceNamespaceList(namespaceList), nil
+}
+
+// GetResourceNamespaceWatch returns a watch for events that occur on kube namespaces returning a list of all the namespaces
+func (client *kubeClientResourceNamespaceLister) GetResourceNamespaceWatch(opts resources.ResourceNamespaceWatchOptions, filtered resources.ResourceNamespaceList) (chan resources.ResourceNamespaceList, <-chan error, error) {
+	excludeNamespaces := client.getExcludeFieldSelector(filtered)
+	namespaceWatcher, err := client.kube.CoreV1().Namespaces().Watch(opts.Ctx, metav1.ListOptions{FieldSelector: excludeNamespaces, LabelSelector: opts.ExpressionSelector})
+	if err != nil {
+		return nil, nil, err
+	}
+	namespaceChan := namespaceWatcher.ResultChan()
+	resourceNamespaceChan := make(chan resources.ResourceNamespaceList)
+	errorChannel := make(chan error)
+	go func() {
+		defer func() {
+			close(resourceNamespaceChan)
+			close(errorChannel)
+		}()
+		for {
+			select {
+			case <-opts.Ctx.Done():
+				return
+			case event, ok := <-namespaceChan:
+				if !ok {
+					return
+				}
+				switch event.Type {
+				case kubewatch.Error:
+					errorChannel <- errors.Errorf("error with the event from watching namespaces: %v", event)
+					return
+				default:
+					resourceNamespaceList, err := client.GetResourceNamespaceList(resources.ResourceNamespaceListOptions{
+						Ctx:                opts.Ctx,
+						ExpressionSelector: opts.ExpressionSelector,
+					}, filtered)
+					if err != nil {
+						errorChannel <- errors.Wrap(err, "error getting the list of resource namespaces while watching")
+						return
+					}
+					resourceNamespaceChan <- resourceNamespaceList
+				}
+			}
+		}
+	}()
+	return resourceNamespaceChan, errorChannel, nil
+}
+
+func (client *kubeClientResourceNamespaceLister) getExcludeFieldSelector(filtered resources.ResourceNamespaceList) string {
+	var buffer bytes.Buffer
+	for i, rns := range filtered {
+		ns := rns.Name
+		if ns != "" {
+			buffer.WriteString("metadata.name!=")
+			buffer.WriteString(ns)
+			if i < len(filtered)-1 {
+				buffer.WriteByte(',')
+			}
+		}
+	}
+	return buffer.String()
+}
+
+func convertNamespaceListToResourceNamespaceList(namespaceList *kubev1.NamespaceList) resources.ResourceNamespaceList {
+	resourceNamespaces := make(resources.ResourceNamespaceList, len(namespaceList.Items))
+	for i, item := range namespaceList.Items {
+		ns := item.Name
+		resourceNamespaces[i] = resources.ResourceNamespace{Name: ns}
+	}
+	return resourceNamespaces
+}

pkg/api/v1/clients/common/common.go

@@ -37,10 +37,8 @@ func KubeResourceWatch(cache cache.Cache, listFunc ResourceListFunc, namespace s
 	// prevent flooding the channel with duplicates
 	var previous *resources.ResourceList
 	updateResourceList := func() {
-		list, err := listFunc(namespace, clients.ListOpts{
-			Ctx:      opts.Ctx,
-			Selector: opts.Selector,
-		})
+		lopts := clients.TranslateWatchOptsIntoListOpts(opts)
+		list, err := listFunc(namespace, lopts)
 		if err != nil {
 			errs <- err
 			return

pkg/api/v1/clients/kube/resource_client.go

@@ -23,7 +23,6 @@ import (
 	"go.opencensus.io/tag"
 	apierrors "k8s.io/apimachinery/pkg/api/errors"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
-	"k8s.io/apimachinery/pkg/labels"
 )
 
 var (
@@ -296,7 +295,7 @@ func (rc *ResourceClient) List(namespace string, opts clients.ListOpts) (resourc
 		return nil, err
 	}
 
-	labelSelector, err := rc.getLabelSelector(opts)
+	labelSelector, err := clients.GetLabelSelector(opts)
 	if err != nil {
 		return nil, errors.Wrapf(err, "parsing label selector")
 	}
@@ -414,16 +413,6 @@ func (rc *ResourceClient) Watch(namespace string, opts clients.WatchOpts) (<-cha
 	return resourcesChan, errs, nil
 }
 
-func (rc *ResourceClient) getLabelSelector(listOpts clients.ListOpts) (labels.Selector, error) {
-	// https://kubernetes.io/docs/concepts/overview/working-with-objects/labels/#set-based-requirement
-	if listOpts.ExpressionSelector != "" {
-		return labels.Parse(listOpts.ExpressionSelector)
-	}
-
-	// https://kubernetes.io/docs/concepts/overview/working-with-objects/labels/#equality-based-requirement
-	return labels.SelectorFromSet(listOpts.Selector), nil
-}
-
 // Checks whether the group version kind of the given resource matches that of the client's underlying CRD:
 func (rc *ResourceClient) matchesClientGVK(resource v1.Resource) bool {
 	return resource.GroupVersionKind().String() == rc.crd.GroupVersionKind().String()

pkg/api/v1/clients/options.go

@@ -0,0 +1,35 @@
+package clients
+
+import (
+	"github.com/solo-io/solo-kit/pkg/api/v1/resources"
+	"k8s.io/apimachinery/pkg/labels"
+)
+
+// GetLabelSelector will parse ExpresionSelector if present, else it selects Selector.
+func GetLabelSelector(listOpts ListOpts) (labels.Selector, error) {
+	// https://kubernetes.io/docs/concepts/overview/working-with-objects/labels/#set-based-requirement
+	if listOpts.ExpressionSelector != "" {
+		return labels.Parse(listOpts.ExpressionSelector)
+	}
+
+	// https://kubernetes.io/docs/concepts/overview/working-with-objects/labels/#equality-based-requirement
+	return labels.SelectorFromSet(listOpts.Selector), nil
+}
+
+// TranslateWatchOptsIntoListOpts translates the watch options into list options
+func TranslateWatchOptsIntoListOpts(wopts WatchOpts) ListOpts {
+	clopts := ListOpts{Ctx: wopts.Ctx, ExpressionSelector: wopts.ExpressionSelector, Selector: wopts.Selector}
+	return clopts
+}
+
+// TranslateResourceNamespaceListToListOptions translates the resource namespace list options to List Options
+func TranslateResourceNamespaceListToListOptions(lopts resources.ResourceNamespaceListOptions) ListOpts {
+	clopts := ListOpts{Ctx: lopts.Ctx, ExpressionSelector: lopts.ExpressionSelector}
+	return clopts
+}
+
+// TranslateResourceNamespaceListToWatchOptions translates the resource namespace watch options to Watch Options
+func TranslateResourceNamespaceListToWatchOptions(wopts resources.ResourceNamespaceWatchOptions) WatchOpts {
+	clopts := WatchOpts{Ctx: wopts.Ctx, ExpressionSelector: wopts.ExpressionSelector}
+	return clopts
+}

pkg/api/v1/resources/resource_interface.go

@@ -1,6 +1,7 @@
 package resources
 
 import (
+	"context"
 	"fmt"
 	"reflect"
 	"sort"
@@ -80,6 +81,62 @@ type CustomInputResource interface {
 	MarshalStatus() (v1.Status, error)
 }
 
+// ResourceNamespaceListOptions provides the options for listing Resource Namespaces
+type ResourceNamespaceListOptions struct {
+	// Ctx is the context
+	Ctx context.Context
+
+	// Equality-based label requirements
+	// https://kubernetes.io/docs/concepts/overview/working-with-objects/labels/#equality-based-requirement
+	// Equality-based requirements allow filtering by label keys and values.
+	// Matching objects must satisfy all of the specified label constraints,
+	// though they may have additional labels as well.
+	// Example:
+	//	{product: edge} would return all objects with a label key equal to
+	//	product and label value equal to edge
+	// If both ExpressionSelector and Selector are defined, ExpressionSelector is preferred
+	ExpressionSelector string
+}
+
+// ResourceNamespaceWatchOptions provides the options for watching Resource Namespaces
+type ResourceNamespaceWatchOptions struct {
+	// Ctx is the context
+	Ctx context.Context
+	// Equality-based label requirements
+	// https://kubernetes.io/docs/concepts/overview/working-with-objects/labels/#equality-based-requirement
+	// Equality-based requirements allow filtering by label keys and values.
+	// Matching objects must satisfy all of the specified label constraints,
+	// though they may have additional labels as well.
+	// Example:
+	//	{product: edge} would return all objects with a label key equal to
+	//	product and label value equal to edge
+	// If both ExpressionSelector and Selector are defined, ExpressionSelector is preferred
+	ExpressionSelector string
+}
+
+// ResoruceNamespace is the namespaces that resources can be found. ResourceNamespaces are
+// anything that contains resources independent of other resoruces. They provide sections
+// independent infrastructure or regions. IE kubernetes namespaces
+type ResourceNamespace struct {
+	// Name the name of the namespace
+	Name string
+}
+
+// ResourceNamespaceList contains a list of ResourceNamespaces
+type ResourceNamespaceList []ResourceNamespace
+
+// ResourceNamespaceLister is anything that can list and watch namespaces that
+// resources can be found.
+type ResourceNamespaceLister interface {
+	// GetResourceNamespaceList returns the list of the namespaces that resources
+	// can be found. The list returned will not contain namespacesToFilter.
+	GetResourceNamespaceList(opts ResourceNamespaceListOptions, namespacesToFilter ResourceNamespaceList) (ResourceNamespaceList, error)
+	// GetResourceNamespaceWatch returns a watch that receives events when namespaces
+	// are updated or created. The channel will not return namespacesToFilter. Use the errs for when
+	// errors are async.
+	GetResourceNamespaceWatch(opts ResourceNamespaceWatchOptions, namespacesToFilter ResourceNamespaceList) (chan ResourceNamespaceList, <-chan error, error)
+}
+
 type ResourceList []Resource
 type ResourcesById map[string]Resource
 type ResourcesByKind map[string]ResourceList