add a new example

_examples/configuration/multi-environments/cmd/root_command.go

@@ -0,0 +1,50 @@
+package cmd
+
+import (
+	"github.com/kataras/my-iris-app/api"
+
+	"github.com/spf13/cobra"
+)
+
+const defaultConfigFilename = "server.dev.yml"
+
+var (
+	serverConfig api.Configuration
+)
+
+// New returns a new root command.
+// Usage:
+// $ my-iris-app --config=server.yml
+func New() *cobra.Command {
+	configFile := defaultConfigFilename
+
+	rootCmd := &cobra.Command{
+		Use:                        "my-iris-app",
+		Short:                      "My Command Line App",
+		Long:                       "The root command will start the HTTP server.",
+		Version:                    "v0.0.1",
+		SilenceErrors:              true,
+		SilenceUsage:               true,
+		TraverseChildren:           true,
+		SuggestionsMinimumDistance: 1,
+		PersistentPreRunE: func(cmd *cobra.Command, args []string) error {
+			return serverConfig.BindFile(configFile)
+		},
+		RunE: func(cmd *cobra.Command, args []string) error {
+			return startServer()
+		},
+	}
+
+	// Shared flags.
+	flags := rootCmd.PersistentFlags()
+	flags.StringVar(&configFile, "config", configFile, "--config=server.yml a filepath which contains the YAML config format")
+
+	// Subcommands here.
+
+	return rootCmd
+}
+
+func startServer() error {
+	srv := api.NewServer(serverConfig)
+	return srv.Listen()
+}