feat: Init Command

cmd/tk/init.go

@@ -0,0 +1,81 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"log"
+	"os"
+
+	"github.com/sh0rez/tanka/pkg/config/v1alpha1"
+	"github.com/spf13/cobra"
+)
+
+// initCmd creates a new application
+func initCmd() *cobra.Command {
+	cmd := &cobra.Command{
+		Use:   "init",
+		Short: "Create the directory structure",
+	}
+	force := cmd.Flags().BoolP("force", "f", false, "ignore the working directory not being empty")
+	provider := cmd.Flags().StringP("provider", "p", "", fmt.Sprintf("one of %s", listProviders()))
+	cmd.Run = func(cmd *cobra.Command, args []string) {
+		files, err := ioutil.ReadDir(".")
+		if err != nil {
+			log.Fatalln("Error listing files:", err)
+		}
+		if len(files) > 0 && !*force {
+			log.Fatalln("Error: directory not empty. Use `-f` to force")
+		}
+
+		if err := writeNewFile("jsonnetfile.json", "{}"); err != nil {
+			log.Fatalln("Error creating `jsonnetfile.json`:", err)
+		}
+
+		if err := os.Mkdir("vendor", os.ModePerm); err != nil {
+			log.Fatalln("Error creating `vendor/` folder:", err)
+		}
+
+		if err := os.Mkdir("lib", os.ModePerm); err != nil {
+			log.Fatalln("Error creating `vendor/` folder:", err)
+		}
+
+		if err := os.MkdirAll("environments/default", os.ModePerm); err != nil {
+			log.Fatalln("Error creating environments folder")
+		}
+
+		if err := writeNewFile("environments/default/main.jsonnet", "{}"); err != nil {
+			log.Fatalln("Error creating `main.jsonnet`:", err)
+		}
+
+		cfg := v1alpha1.Config{
+			APIVersion: "tanka.dev/v1alpha1",
+			Kind:       "Environment",
+		}
+		if *provider != "" {
+			cfg.Spec = map[string]interface{}{}
+			cfg.Spec["provider"] = map[string]interface{}{
+				*provider: map[string]interface{}{},
+			}
+		}
+
+		spec, err := json.Marshal(&cfg)
+		if err != nil {
+			log.Fatalln("Error creating spec.json:", err)
+		}
+
+		if err := writeNewFile("environments/default/spec.json", string(spec)); err != nil {
+			log.Fatalln("Error creating `environments/default/spec.json`:", err)
+		}
+
+	}
+	return cmd
+}
+
+// writeNewFile writes the content to a file if it does not exist
+func writeNewFile(name, content string) error {
+	if _, err := os.Stat(name); os.IsNotExist(err) {
+		return ioutil.WriteFile(name, []byte(content), 0644)
+	}
+	return nil
+}

cmd/tk/main.go

@@ -2,15 +2,15 @@ package main
 
 import (
 	"log"
+	"os"
 
+	"github.com/mitchellh/mapstructure"
 	"github.com/spf13/cobra"
 	"github.com/spf13/viper"
 
 	"github.com/sh0rez/tanka/pkg/config/v1alpha1"
 	"github.com/sh0rez/tanka/pkg/provider"
 	"github.com/sh0rez/tanka/pkg/provider/kubernetes"
-
-	"github.com/mitchellh/mapstructure"
 )
 
 var Version = "dev"
@@ -57,6 +57,7 @@ func main() {
 	// jsonnet commands
 	rootCmd.AddCommand(
 		evalCmd(),
+		initCmd(),
 		fmtCmd(),
 		debugCmd(),
 	)
@@ -77,7 +78,10 @@ func main() {
 	if err := viper.ReadInConfig(); err != nil {
 		// just run fine without config. Provider features won't work (apply, show, diff)
 		if _, ok := err.(viper.ConfigFileNotFoundError); ok {
-			log.Fatalln(rootCmd.Execute())
+			if err := rootCmd.Execute(); err != nil {
+				log.Fatalln("Ouch:", err)
+			}
+			os.Exit(1)
 		}
 
 		log.Fatalln(err)

cmd/tk/provider.go

@@ -26,19 +26,23 @@ func providerListCmd() *cobra.Command {
 		Use:   "list",
 		Short: "print all available providers",
 		Run: func(cmd *cobra.Command, args []string) {
-			keys := make([]string, len(providers))
-
-			i := 0
-			for k := range providers {
-				keys[i] = k
-				i++
-			}
-			log.Println("Available providers:", keys)
+			log.Println("Available providers:", listProviders())
 		},
 	}
 	return cmd
 }
 
+func listProviders() []string {
+	keys := make([]string, len(providers))
+
+	i := 0
+	for k := range providers {
+		keys[i] = k
+		i++
+	}
+	return keys
+}
+
 func applyCmd() *cobra.Command {
 	cmd := &cobra.Command{
 		Use:   "apply",