Add version command

Makefile

@@ -1,12 +1,19 @@
 OUTPUT ?= astro
 
+GIT_COMMIT=$(shell git rev-parse HEAD)
+GIT_COMMIT_SHORT=$(shell git rev-parse --short HEAD)
+VERSION ?= SNAPSHOT-${GIT_COMMIT_SHORT}
+
+LDFLAGS_VERSION=-X github.com/astronomerio/astro-cli/cmd.version=${VERSION} 
+LDFLAGS_GIT_COMMIT=-X github.com/astronomerio/astro-cli/cmd.gitcommit=${GIT_COMMIT}
+
 .DEFAULT_GOAL := build
 
 dep:
 	dep ensure
 
 build:
-	go build -o ${OUTPUT} main.go
+	go build -o ${OUTPUT} -ldflags "${LDFLAGS_VERSION} ${LDFLAGS_GIT_COMMIT}" main.go
 
 install: build
 	$(eval DESTDIR ?= $(GOBIN))

cmd/version.go

@@ -0,0 +1,28 @@
+package cmd
+
+import (
+	"fmt"
+
+	"github.com/spf13/cobra"
+)
+
+var (
+	version    = ""
+	gitcommit  = ""
+	versionCmd = &cobra.Command{
+		Use:   "version",
+		Short: "Astronomer CLI version",
+		Long:  "Astronomer CLI version",
+		RunE:  printVersion,
+	}
+)
+
+func init() {
+	RootCmd.AddCommand(versionCmd)
+}
+
+func printVersion(cmd *cobra.Command, args []string) error {
+	fmt.Printf("Astro CLI Version: %s\n", version)
+	fmt.Printf("Git Commit: %s\n", gitcommit)
+	return nil
+}