test: add applier tool (#11143)

Signed-off-by: Yuval Kohavi <yuval.kohavi@gmail.com>

Author: yuval-k

hack/utils/applier/README.md

@@ -0,0 +1,52 @@
+# How to use this?
+
+Run like so
+
+```
+go run main.go apply -f yamls.yaml --iterations 3000
+```
+This will apply the template in yamls.yaml 3000 times.
+The template has an `.Index` variable you can use.
+
+For example, for a pod, you would have:
+```yaml
+apiVersion: v1
+kind: Pod
+metadata:
+  name: app-{{.Index}}
+  namespace: gloo-system
+  labels:
+    app: app-{{.Index}}
+    test: test1
+spec:
+  containers:
+  - name: app
+    image: registry.k8s.io/pause:3.6
+    resources:
+      limits:
+        memory: "1Mi"
+        cpu: "1m"
+    ports:
+      - containerPort: 8080
+```
+
+this will create pods name `app-0`, `app-1`,...
+
+You can also:
+- use `--dry-run` to just print yamls.
+- adjust `--qps` and `--burst` as well.
+- If your broke the cluster, you can use `--start` to continue from where you left off.
+
+By default, objects will not be overridden. This is because
+that a common failure mode here is that the cluster stops responding. When the cluster recovers you don't need to re-create the same object, so a simple create is enough. To change this behavior use `--force` to first delete objects and then re-create them.
+
+To clean up (just delete the objects), pass the `--delete` flag.
+
+If you are still not hitting the QPS set, try adding the `--async` flag to have requests going in parallel (you can also adjust `--workers`).
+
+## Caveat
+
+The template is parsed on the field level. This means that the input files must be valid yaml files. This is because the yaml is parsed **before** the template is evaluated.
+Only after the yaml is parsed, we go over all the fields and evaluate the templates on each field.
+
+This is a technical limitation is due to trying to give a similar experience to `kubectl apply`.

hack/utils/applier/cmd/apply.go

@@ -0,0 +1,123 @@
+package cmd
+
+import (
+	"fmt"
+
+	"github.com/spf13/cobra"
+	"k8s.io/cli-runtime/pkg/genericclioptions"
+	"k8s.io/cli-runtime/pkg/resource"
+	"k8s.io/client-go/dynamic"
+	"k8s.io/client-go/tools/clientcmd"
+	cmdutil "k8s.io/kubectl/pkg/cmd/util"
+
+	"github.com/kgateway-dev/kgateway/hack/utils/applier/pkg/applier"
+)
+
+var (
+	fileNameFlags *genericclioptions.FileNameFlags
+
+	dryRun        bool
+	startIndex    int
+	endIndex      int
+	numIterations int
+	force         bool
+
+	delete bool
+
+	async   bool
+	workers int
+
+	qps   float32
+	burst int
+)
+
+// applyCmd represents the apply command
+var applyCmd = &cobra.Command{
+	Use: "apply",
+	RunE: func(cmd *cobra.Command, args []string) error {
+		fmt.Println("apply called")
+
+		if burst < int(qps) {
+			burst = int(qps)
+		}
+
+		configFlags.WithDiscoveryBurst(burst).WithDiscoveryQPS(qps)
+
+		userSpecifiedContext, err := cmd.Flags().GetString("context")
+		if err != nil {
+			return err
+		}
+
+		restConfig, err := clientcmd.NewNonInteractiveDeferredLoadingClientConfig(
+			&clientcmd.ClientConfigLoadingRules{ExplicitPath: configFlags.ToRawKubeConfigLoader().ConfigAccess().GetDefaultFilename()},
+			&clientcmd.ConfigOverrides{
+				CurrentContext: userSpecifiedContext,
+			}).ClientConfig()
+		if err != nil {
+			return err
+		}
+
+		restConfig.QPS = qps
+		restConfig.Burst = burst
+
+		factory := cmdutil.NewFactory(matchVersionKubeConfigFlags)
+		validationDirective, err := cmdutil.GetValidationDirective(cmd)
+		if err != nil {
+			return err
+		}
+
+		dynamicClient, err := dynamic.NewForConfig(restConfig)
+		if err != nil {
+			return err
+		}
+		fieldValidationVerifier := resource.NewQueryParamVerifier(dynamicClient, factory.OpenAPIGetter(), resource.QueryParamFieldValidation)
+
+		validator, err := factory.Validator(validationDirective, fieldValidationVerifier)
+		if err != nil {
+			return err
+		}
+		filenameOptions := fileNameFlags.ToOptions()
+
+		if numIterations > 0 {
+			endIndex = startIndex + numIterations
+		}
+
+		a := applier.Applier{
+			Start:  startIndex,
+			End:    endIndex,
+			DryRun: dryRun,
+			Force:  force,
+			Delete: delete,
+
+			Async:   async,
+			Workers: workers,
+		}
+
+		return a.Apply(dynamicClient, factory, filenameOptions, validator)
+	},
+}
+
+func init() {
+	rootCmd.AddCommand(applyCmd)
+
+	filenames := []string{}
+	recursive := false
+	kustomize := ""
+	fileNameFlags = &genericclioptions.FileNameFlags{Usage: "", Filenames: &filenames, Kustomize: &kustomize, Recursive: &recursive}
+
+	fileNameFlags.AddFlags(applyCmd.PersistentFlags())
+	cmdutil.AddValidateFlags(applyCmd)
+
+	applyCmd.Flags().IntVar(&startIndex, "start", 0, "Start index for the loop")
+	applyCmd.Flags().IntVar(&numIterations, "iterations", 0, "If set, end index will be set to start+this")
+	applyCmd.Flags().IntVar(&endIndex, "end", 3000, "End index for the loop. (If start is 0, this is the number times to apply the manifest)")
+	applyCmd.Flags().BoolVarP(&dryRun, "dry-run", "d", false, "Dry run - print yamls to stdout")
+	applyCmd.Flags().BoolVar(&force, "force", false, "Force apply - delete and recreate objects")
+	applyCmd.Flags().Float32Var(&qps, "qps", 50, "QPS")
+	applyCmd.Flags().IntVar(&burst, "burst", 75, "Burst")
+
+	applyCmd.Flags().BoolVar(&async, "async", false, "Run in async mode. Use this if not hitting your QPS.")
+	applyCmd.Flags().IntVar(&workers, "workers", 10, "Number of workers to use when using async mode. each worker submits requests in parallel.")
+
+	applyCmd.Flags().BoolVar(&delete, "delete", false, "Delete resources instead of applying them (useful for cleanup)")
+}

hack/utils/applier/cmd/root.go

@@ -0,0 +1,34 @@
+package cmd
+
+import (
+	"os"
+
+	"github.com/spf13/cobra"
+	"k8s.io/cli-runtime/pkg/genericclioptions"
+	cmdutil "k8s.io/kubectl/pkg/cmd/util"
+)
+
+var (
+	configFlags                 = genericclioptions.NewConfigFlags(true)
+	matchVersionKubeConfigFlags = cmdutil.NewMatchVersionFlags(configFlags)
+)
+
+// rootCmd represents the base command when called without any subcommands
+var rootCmd = &cobra.Command{
+	Use: "applier",
+}
+
+// Execute adds all child commands to the root command and sets flags appropriately.
+// This is called by main.main(). It only needs to happen once to the rootCmd.
+func Execute() {
+	err := rootCmd.Execute()
+	if err != nil {
+		os.Exit(1)
+	}
+}
+
+func init() {
+	configFlags.AddFlags(rootCmd.PersistentFlags())
+	matchVersionKubeConfigFlags.AddFlags(rootCmd.PersistentFlags())
+
+}

hack/utils/applier/go.mod

@@ -0,0 +1,92 @@
+module github.com/kgateway-dev/kgateway/hack/utils/applier
+
+go 1.19
+
+require (
+	github.com/cheggaaa/pb/v3 v3.1.0
+	github.com/spf13/cobra v1.5.0
+	k8s.io/apimachinery v0.25.2
+	k8s.io/cli-runtime v0.25.2
+	k8s.io/client-go v0.25.2
+	k8s.io/kubectl v0.25.2
+)
+
+require (
+	cloud.google.com/go v0.97.0 // indirect
+	github.com/Azure/go-ansiterm v0.0.0-20210617225240-d185dfc1b5a1 // indirect
+	github.com/Azure/go-autorest v14.2.0+incompatible // indirect
+	github.com/Azure/go-autorest/autorest v0.11.27 // indirect
+	github.com/Azure/go-autorest/autorest/adal v0.9.20 // indirect
+	github.com/Azure/go-autorest/autorest/date v0.3.0 // indirect
+	github.com/Azure/go-autorest/logger v0.2.1 // indirect
+	github.com/Azure/go-autorest/tracing v0.6.0 // indirect
+	github.com/MakeNowJust/heredoc v1.0.0 // indirect
+	github.com/PuerkitoBio/purell v1.1.1 // indirect
+	github.com/PuerkitoBio/urlesc v0.0.0-20170810143723-de5bf2ad4578 // indirect
+	github.com/VividCortex/ewma v1.1.1 // indirect
+	github.com/chai2010/gettext-go v1.0.2 // indirect
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/emicklei/go-restful/v3 v3.8.0 // indirect
+	github.com/evanphx/json-patch v4.12.0+incompatible // indirect
+	github.com/exponent-io/jsonpath v0.0.0-20151013193312-d6023ce2651d // indirect
+	github.com/fatih/color v1.10.0 // indirect
+	github.com/go-errors/errors v1.0.1 // indirect
+	github.com/go-logr/logr v1.2.3 // indirect
+	github.com/go-openapi/jsonpointer v0.19.5 // indirect
+	github.com/go-openapi/jsonreference v0.19.5 // indirect
+	github.com/go-openapi/swag v0.19.14 // indirect
+	github.com/gogo/protobuf v1.3.2 // indirect
+	github.com/golang-jwt/jwt/v4 v4.2.0 // indirect
+	github.com/golang/protobuf v1.5.2 // indirect
+	github.com/google/btree v1.0.1 // indirect
+	github.com/google/gnostic v0.5.7-v3refs // indirect
+	github.com/google/gofuzz v1.1.0 // indirect
+	github.com/google/shlex v0.0.0-20191202100458-e7afc7fbc510 // indirect
+	github.com/google/uuid v1.1.2 // indirect
+	github.com/gregjones/httpcache v0.0.0-20180305231024-9cad4c3443a7 // indirect
+	github.com/imdario/mergo v0.3.6 // indirect
+	github.com/inconshreveable/mousetrap v1.0.0 // indirect
+	github.com/josharian/intern v1.0.0 // indirect
+	github.com/json-iterator/go v1.1.12 // indirect
+	github.com/liggitt/tabwriter v0.0.0-20181228230101-89fcab3d43de // indirect
+	github.com/mailru/easyjson v0.7.6 // indirect
+	github.com/mattn/go-colorable v0.1.8 // indirect
+	github.com/mattn/go-isatty v0.0.12 // indirect
+	github.com/mattn/go-runewidth v0.0.12 // indirect
+	github.com/mitchellh/go-wordwrap v1.0.0 // indirect
+	github.com/moby/spdystream v0.2.0 // indirect
+	github.com/moby/term v0.0.0-20210619224110-3f7ff695adc6 // indirect
+	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
+	github.com/modern-go/reflect2 v1.0.2 // indirect
+	github.com/monochromegane/go-gitignore v0.0.0-20200626010858-205db1a8cc00 // indirect
+	github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 // indirect
+	github.com/peterbourgon/diskv v2.0.1+incompatible // indirect
+	github.com/pkg/errors v0.9.1 // indirect
+	github.com/rivo/uniseg v0.2.0 // indirect
+	github.com/russross/blackfriday v1.5.2 // indirect
+	github.com/spf13/pflag v1.0.5 // indirect
+	github.com/xlab/treeprint v1.1.0 // indirect
+	go.starlark.net v0.0.0-20200306205701-8dd3e2ee1dd5 // indirect
+	golang.org/x/crypto v0.0.0-20220315160706-3147a52a75dd // indirect
+	golang.org/x/net v0.0.0-20220722155237-a158d28d115b // indirect
+	golang.org/x/oauth2 v0.0.0-20211104180415-d3ed0bb246c8 // indirect
+	golang.org/x/sys v0.0.0-20220722155257-8c9f86f7a55f // indirect
+	golang.org/x/term v0.0.0-20210927222741-03fcf44c2211 // indirect
+	golang.org/x/text v0.3.7 // indirect
+	golang.org/x/time v0.0.0-20220210224613-90d013bbcef8 // indirect
+	google.golang.org/appengine v1.6.7 // indirect
+	google.golang.org/protobuf v1.28.0 // indirect
+	gopkg.in/inf.v0 v0.9.1 // indirect
+	gopkg.in/yaml.v2 v2.4.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+	k8s.io/api v0.25.2 // indirect
+	k8s.io/component-base v0.25.2 // indirect
+	k8s.io/klog/v2 v2.70.1 // indirect
+	k8s.io/kube-openapi v0.0.0-20220803162953-67bda5d908f1 // indirect
+	k8s.io/utils v0.0.0-20220728103510-ee6ede2d64ed // indirect
+	sigs.k8s.io/json v0.0.0-20220713155537-f223a00ba0e2 // indirect
+	sigs.k8s.io/kustomize/api v0.12.1 // indirect
+	sigs.k8s.io/kustomize/kyaml v0.13.9 // indirect
+	sigs.k8s.io/structured-merge-diff/v4 v4.2.3 // indirect
+	sigs.k8s.io/yaml v1.2.0 // indirect
+)