[GSoC 2019] kubectl plugin for the Postgres operator (#579)

* Add a prototype of a kubectl plugin for the Postgres operator Work done by Vineeth Pothulapati <vineethpothulapati@outlook.com> during Google Summer of Code 2019
2026-10-19 00:01:06 +02:00 · 2019-08-27 12:51:21 +02:00
parent 056b2222a5
commit fd6a2454e8
19 changed files with 2191 additions and 0 deletions
@@ -0,0 +1,170 @@
+/*
+Copyright © 2019 Vineeth Pothulapati <vineethpothulapati@outlook.com>
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+package cmd
+
+import (
+	"flag"
+	"fmt"
+	PostgresqlLister "github.com/zalando/postgres-operator/pkg/generated/clientset/versioned/typed/acid.zalan.do/v1"
+	v1 "k8s.io/api/apps/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/client-go/kubernetes"
+	restclient "k8s.io/client-go/rest"
+	"k8s.io/client-go/tools/clientcmd"
+	"k8s.io/client-go/util/homedir"
+	"log"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strconv"
+	"strings"
+)
+
+const (
+	OperatorName     = "postgres-operator"
+	DefaultNamespace = "default"
+)
+
+func getConfig() *restclient.Config {
+	var kubeconfig *string
+	var config *restclient.Config
+	envKube := os.Getenv("KUBECONFIG")
+	if envKube != "" {
+		kubeconfig = &envKube
+	} else {
+		if home := homedir.HomeDir(); home != "" {
+			kubeconfig = flag.String("kubeconfig", filepath.Join(home, ".kube", "config"), "(optional) absolute path to the kubeconfig file")
+		} else {
+			kubeconfig = flag.String("kubeconfig", "", "absolute path to the kubeconfig file")
+		}
+	}
+	flag.Parse()
+	var err error
+	config, err = clientcmd.BuildConfigFromFlags("", *kubeconfig)
+	if err != nil {
+		log.Fatal(err)
+	}
+	return config
+}
+
+func getCurrentNamespace() string {
+	namespace, err := exec.Command("kubectl", "config", "view", "--minify", "--output", "jsonpath={..namespace}").CombinedOutput()
+	if err != nil {
+		log.Fatal(err)
+	}
+	currentNamespace := string(namespace)
+	if currentNamespace == "" {
+		currentNamespace = DefaultNamespace
+	}
+	return currentNamespace
+}
+
+func confirmAction(clusterName string, namespace string) {
+	for {
+		confirmClusterDetails := ""
+		_, err := fmt.Scan(&confirmClusterDetails)
+		if err != nil {
+			log.Fatalf("couldn't get confirmation from the user %v", err)
+		}
+		clusterDetails := strings.Split(confirmClusterDetails, "/")
+		if clusterDetails[0] != namespace || clusterDetails[1] != clusterName {
+			fmt.Printf("cluster name or namespace doesn't match. Please re-enter %s/%s\nHint: Press (ctrl+c) to exit\n", namespace, clusterName)
+		} else {
+			return
+		}
+	}
+}
+
+func getPodName(clusterName string, master bool, replicaNumber string) string {
+	config := getConfig()
+	client, er := kubernetes.NewForConfig(config)
+	if er != nil {
+		log.Fatal(er)
+	}
+
+	postgresConfig, err := PostgresqlLister.NewForConfig(config)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	postgresCluster, err := postgresConfig.Postgresqls(getCurrentNamespace()).Get(clusterName, metav1.GetOptions{})
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	numOfInstances := postgresCluster.Spec.NumberOfInstances
+	var podName string
+	var podRole string
+	replica := clusterName + "-" + replicaNumber
+
+	for ins := 0; ins < int(numOfInstances); ins++ {
+		pod, err := client.CoreV1().Pods(getCurrentNamespace()).Get(clusterName+"-"+strconv.Itoa(ins), metav1.GetOptions{})
+		if err != nil {
+			log.Fatal(err)
+		}
+
+		podRole = pod.Labels["spilo-role"]
+		if podRole == "master" && master {
+			podName = pod.Name
+			fmt.Printf("connected to %s with pod name as %s\n", podRole, podName)
+			break
+		} else if podRole == "replica" && !master && (pod.Name == replica || replicaNumber == "") {
+			podName = pod.Name
+			fmt.Printf("connected to %s with pod name as %s\n", podRole, podName)
+			break
+		}
+	}
+	if podName == "" {
+		log.Fatal("Provided replica doesn't exist")
+	}
+	return podName
+}
+
+func getPostgresOperator(k8sClient *kubernetes.Clientset) *v1.Deployment {
+	var operator *v1.Deployment
+	operator, err := k8sClient.AppsV1().Deployments(getCurrentNamespace()).Get(OperatorName, metav1.GetOptions{})
+	if err == nil {
+		return operator
+	}
+
+	allDeployments := k8sClient.AppsV1().Deployments("")
+	listDeployments, err := allDeployments.List(metav1.ListOptions{})
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	for _, deployment := range listDeployments.Items {
+		if deployment.Name == OperatorName {
+			operator = deployment.DeepCopy()
+			break
+		} else {
+			for key, value := range deployment.Labels {
+				if key == "app.kubernetes.io/name" && value == OperatorName {
+					operator = deployment.DeepCopy()
+					break
+				}
+			}
+		}
+	}
+	return operator
+}