Initial commit

2019-02-27 16:05:41 +01:00
commit 4ad61b6640
5 changed files with 208 additions and 0 deletions
@@ -0,0 +1,148 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"runtime"
+	"strings"
+
+	"io/ioutil"
+
+	"gopkg.in/yaml.v2"
+)
+
+type Clusters struct {
+	Cluster struct {
+		InsecureSkipTLSVerify bool   `yaml:"insecure-skip-tls-verify"`
+		CertificateAuthorityData string `yaml:"certificate-authority-data"`
+		Server                string `yaml:"server"`
+	} `yaml:"cluster"`
+	Name string `yaml:"name"`
+}
+
+type Users struct {
+	Name string `yaml:"name"`
+	User struct {
+		ClientCertificateData string `yaml:"client-certificate-data"`
+		ClientKeyData         string `yaml:"client-key-data"`
+		Username			  string `yaml:"username"`
+		Password			  string `yaml:"password"`
+	} `yaml:"user"`
+}
+
+type Kubecfg struct {
+	APIVersion string `yaml:"apiVersion"`
+	Clusters   []Clusters `yaml:"clusters"`
+	Contexts []struct {
+		Context struct {
+			Cluster string `yaml:"cluster"`
+			User    string `yaml:"user"`
+		} `yaml:"context"`
+		Name string `yaml:"name"`
+	} `yaml:"contexts"`
+	CurrentContext string `yaml:"current-context"`
+	Kind           string `yaml:"kind"`
+	Preferences    struct {
+	} `yaml:"preferences"`
+	Users []Users `yaml:"users"`
+}
+
+func main() {
+	cfg := Kubecfg{}
+
+	home := userHomeDir()
+	data, err := ioutil.ReadFile(strings.Join([]string{home, ".kube", "config"}, "/"))
+
+	if err != nil {
+		log.Fatalf("error: %v", err)
+	}
+
+	err2 := yaml.Unmarshal(data, &cfg)
+	if err2 != nil {
+		log.Fatalf("error: %v", err2)
+	}
+
+	if len(os.Args) == 1 {
+		fmt.Println("Contexts:")
+		for i := 0; i < len(cfg.Contexts); i++ {
+			name := cfg.Contexts[i].Name
+			fmt.Printf("%v\n", name)
+		}
+	} else {
+		var ix = -1
+		for i, n := range cfg.Contexts {
+			if n.Name == os.Args[1] {
+				ix = i
+				break
+			}
+		}
+
+		if ix == -1 {
+			fmt.Printf("Context named '%v' not found in kube-config\n\n", os.Args[1])
+		} else {
+			cluster := cfg.Contexts[ix].Context.Cluster
+			user := cfg.Contexts[ix].Context.User
+
+			x := Kubecfg{}
+			x.APIVersion = "v1"
+			x.Kind = "Config"
+			x.Contexts = append(x.Contexts, cfg.Contexts[ix])
+			if c, ok := findCluster(cluster, cfg); ok {
+				x.Clusters = append(x.Clusters, c)
+			}
+			if u, ok := findUsers(user, cfg); ok {
+				x.Users = u
+			}
+
+			d, err := yaml.Marshal(&x)
+			if err != nil {
+				log.Fatalf("error: %v", err)
+			}
+			fmt.Printf("%s\n", string(d))
+		}
+	}
+}
+
+func findCluster(cluster string, cfg Kubecfg) (Clusters, bool) {
+	var ix = -1
+	for i, n := range cfg.Clusters {
+		if n.Name == cluster {
+			ix = i
+			break
+		}
+	}
+	if ix != -1 {
+		return cfg.Clusters[ix], true
+	}
+	return Clusters{}, false
+}
+
+func findUsers(user string, cfg Kubecfg) ([]Users, bool) {
+	var users []Users
+	for i, n := range cfg.Users {
+		if strings.HasPrefix(n.Name, user) {
+			users = append(users, cfg.Users[i])
+		}
+	}
+	if len(users) != 0 {
+		return users, true
+	}
+	return users, false
+}
+
+func userHomeDir() string {
+	if runtime.GOOS == "windows" {
+		home := os.Getenv("HOMEDRIVE") + os.Getenv("HOMEPATH")
+		if home == "" {
+			home = os.Getenv("USERPROFILE")
+		}
+		return home
+	} else if runtime.GOOS == "linux" {
+		home := os.Getenv("XDG_CONFIG_HOME")
+		if home != "" {
+			return home
+		}
+	}
+	return os.Getenv("HOME")
+}