feat: Implement CRD client to fetch custom resources

Author: mrajagopal

go.mod

@@ -37,6 +37,7 @@ require (
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 	k8s.io/api v0.29.2 // indirect
 	k8s.io/apimachinery v0.29.2 // indirect
+	k8s.io/apiextensions-apiserver v0.29.2
 	k8s.io/klog/v2 v2.110.1 // indirect
 	k8s.io/kube-openapi v0.0.0-20231010175941-2dd684a91f00 // indirect
 	k8s.io/utils v0.0.0-20230726121419-3b25d923346b // indirect

go.sum

@@ -138,6 +138,8 @@ gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
 gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 k8s.io/api v0.29.2 h1:hBC7B9+MU+ptchxEqTNW2DkUosJpp1P+Wn6YncZ474A=
 k8s.io/api v0.29.2/go.mod h1:sdIaaKuU7P44aoyyLlikSLayT6Vb7bvJNCX105xZXY0=
+k8s.io/apiextensions-apiserver v0.29.2 h1:UK3xB5lOWSnhaCk0RFZ0LUacPZz9RY4wi/yt2Iu+btg=
+k8s.io/apiextensions-apiserver v0.29.2/go.mod h1:aLfYjpA5p3OwtqNXQFkhJ56TB+spV8Gc4wfMhUA3/b8=
 k8s.io/apimachinery v0.29.2 h1:EWGpfJ856oj11C52NRCHuU7rFDwxev48z+6DSlGNsV8=
 k8s.io/apimachinery v0.29.2/go.mod h1:6HVkd1FwxIagpYrHSwJlQqZI3G9LfYWRPAkUvLnXTKU=
 k8s.io/client-go v0.29.2 h1:FEg85el1TeZp+/vYJM7hkDlSTFZ+c5nnK44DJ4FyoRg=

internal/jobs/job.go

@@ -2,6 +2,7 @@ package jobs
 
 import (
 	"context"
+	crdClient "k8s.io/apiextensions-apiserver/pkg/client/clientset/clientset"
 	"k8s.io/client-go/kubernetes"
 	"os"
 	"path"
@@ -14,6 +15,12 @@ type Job struct {
 	RetrieveFunction func(*kubernetes.Clientset, context.Context) []byte
 }
 
+type CustomJob struct {
+	Name             string
+	OutputFile       string
+	RetrieveFunction func(*crdClient.Clientset, context.Context) []byte
+}
+
 func (j Job) Collect(baseFolder string, cs *kubernetes.Clientset) {
 	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
 	defer cancel()
@@ -26,3 +33,16 @@ func (j Job) Collect(baseFolder string, cs *kubernetes.Clientset) {
 	defer file.Close()
 	_, _ = file.Write(result)
 }
+
+func (j CustomJob) CustomCollect(baseFolder string, cs *crdClient.Clientset) {
+	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+	defer cancel()
+	result := j.RetrieveFunction(cs, ctx)
+
+	fullPathFile := path.Join(baseFolder, j.OutputFile)
+	os.MkdirAll(path.Dir(fullPathFile), os.ModePerm)
+
+	file, _ := os.Create(fullPathFile)
+	defer file.Close()
+	_, _ = file.Write(result)
+}

internal/jobs/job_list.go

@@ -3,6 +3,7 @@ package jobs
 import (
 	"context"
 	"encoding/json"
+	crdClient "k8s.io/apiextensions-apiserver/pkg/client/clientset/clientset"
 	v1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/client-go/kubernetes"
 )
@@ -18,6 +19,24 @@ func K8sJobList() []Job {
 				return jsonPods
 			},
 		},
+		{
+			Name:       "configmap-list",
+			OutputFile: "/list/configmaps.json",
+			RetrieveFunction: func(c *kubernetes.Clientset, ctx context.Context) []byte {
+				pods, _ := c.CoreV1().ConfigMaps("").List(ctx, v1.ListOptions{})
+				jsonPods, _ := json.MarshalIndent(pods, "", "  ")
+				return jsonPods
+			},
+		},
+		{
+			Name:       "service-list",
+			OutputFile: "/list/services.json",
+			RetrieveFunction: func(c *kubernetes.Clientset, ctx context.Context) []byte {
+				pods, _ := c.CoreV1().ConfigMaps("").List(ctx, v1.ListOptions{})
+				jsonPods, _ := json.MarshalIndent(pods, "", "  ")
+				return jsonPods
+			},
+		},
 		{
 			Name:       "server-version",
 			OutputFile: "/k8s/server_version.json",
@@ -39,3 +58,18 @@ func K8sJobList() []Job {
 	}
 	return jobList
 }
+
+func K8sCustomJobList() []CustomJob {
+	jobList := []CustomJob{
+		{
+			Name:       "crd-list",
+			OutputFile: "/list/crd.json",
+			RetrieveFunction: func(c *crdClient.Clientset, ctx context.Context) []byte {
+				crds, _ := c.ApiextensionsV1().CustomResourceDefinitions().List(ctx, v1.ListOptions{})
+				jsonCrds, _ := json.MarshalIndent(crds, "", "  ")
+				return jsonCrds
+			},
+		},
+	}
+	return jobList
+}

main.go

@@ -3,6 +3,7 @@ package main
 import (
 	"fmt"
 	"github.com/nginxinc/kubectl-kic-supportpkg/internal/jobs"
+	crdClient "k8s.io/apiextensions-apiserver/pkg/client/clientset/clientset"
 	"k8s.io/client-go/kubernetes"
 	"k8s.io/client-go/tools/clientcmd"
 	"k8s.io/client-go/util/homedir"
@@ -32,4 +33,14 @@ func main() {
 		fmt.Printf("Running %s and collecting the output in %s/%s...\n", job.Name, tmpDir, job.OutputFile)
 		job.Collect(tmpDir, clientSet)
 	}
+
+	// Create a new clientset for CRDs
+	crdClientset, err := crdClient.NewForConfig(config)
+	if err != nil {
+		panic(err.Error())
+	}
+	for _, job := range jobs.K8sCustomJobList() {
+		fmt.Printf("Running %s and collecting the output in %s/%s...\n", job.Name, tmpDir, job.OutputFile)
+		job.CustomCollect(tmpDir, crdClientset)
+	}
 }