feat(build/cmd): include commit/tag and time in 'version' cmd

Makefile

@@ -104,5 +104,13 @@ test: deps generate
 .PHONY: build
 ## builds the binary executable from CLI
 build: $(INSTALL_PREFIX) deps
-	@echo "building $(BINARY_PATH) ..."
-	@go build -o $(BINARY_PATH) cmd/libasciidoc/*.go
+	$(eval BUILD_COMMIT:=$(shell git rev-parse --short HEAD))
+	$(eval BUILD_TAG:=$(shell git tag --contains $(BUILD_COMMIT)))
+	$(eval BUILD_TIME:=$(shell date -u '+%Y-%m-%dT%H:%M:%SZ'))
+	@echo "building $(BINARY_PATH) (commit:$(BUILD_COMMIT) / tag:$(BUILD_TAG) / time:$(BUILD_TIME))"
+	@go build -ldflags \
+	  " -X github.com/bytesparadise/libasciidoc.BuildCommit=$(BUILD_COMMIT)\
+	    -X github.com/bytesparadise/libasciidoc.BuildTag=$(BUILD_TAG) \
+	    -X github.com/bytesparadise/libasciidoc.BuildTime=$(BUILD_TIME)" \
+	  -o $(BINARY_PATH) \
+	  cmd/libasciidoc/*.go

cmd/libasciidoc/main.go

@@ -11,6 +11,7 @@ import (
 
 func main() {
 	rootCmd := NewRootCmd()
+	versionCmd := NewVersionCmd()
 	rootCmd.AddCommand(versionCmd)
 	rootCmd.SetHelpCommand(helpCommand)
 	// rootCmd.SetHelpTemplate(helpTemplate)

cmd/libasciidoc/version_cmd.go

@@ -0,0 +1,24 @@
+package main
+
+import (
+	"fmt"
+
+	"github.com/bytesparadise/libasciidoc"
+	"github.com/spf13/cobra"
+)
+
+// NewVersionCmd returns the root command
+func NewVersionCmd() *cobra.Command {
+	return &cobra.Command{
+		Use:   "version",
+		Short: "Print the version number of libasciidoc",
+		Run: func(cmd *cobra.Command, args []string) {
+			if libasciidoc.BuildTag != "" {
+				fmt.Fprintf(cmd.OutOrStdout(), "tag:        %s\n", libasciidoc.BuildTag)
+			} else {
+				fmt.Fprintf(cmd.OutOrStdout(), "commit:     %s\n", libasciidoc.BuildCommit)
+			}
+			fmt.Fprintf(cmd.OutOrStdout(), "build time: %s\n", libasciidoc.BuildTime)
+		},
+	}
+}

cmd/libasciidoc/version_cmd_test.go

@@ -0,0 +1,26 @@
+package main_test
+
+import (
+	"bytes"
+
+	main "github.com/bytesparadise/libasciidoc/cmd/libasciidoc"
+	. "github.com/onsi/ginkgo"
+	"github.com/stretchr/testify/require"
+)
+
+var _ = Describe("version cmd", func() {
+
+	It("ok", func() {
+		// given
+		versionCmd := main.NewVersionCmd()
+		buf := new(bytes.Buffer)
+		versionCmd.SetOutput(buf)
+		versionCmd.SetArgs([]string{})
+		// when
+		err := versionCmd.Execute()
+		// then
+		require.NoError(GinkgoT(), err)
+		require.NotEmpty(GinkgoT(), buf.String())
+	})
+
+})

libasciidoc.go

@@ -12,6 +12,15 @@ import (
 	log "github.com/sirupsen/logrus"
 )
 
+var (
+	// BuildCommit lastest build commit (set by Makefile)
+	BuildCommit = ""
+	// BuildTag if the `BuildCommit` matches a tag
+	BuildTag = ""
+	// BuildTime set by build script (set by Makefile)
+	BuildTime = ""
+)
+
 // ConvertFileToHTML converts the content of the given filename into an HTML document.
 // The conversion result is written in the given writer `output`, whereas the document metadata (title, etc.) (or an error if a problem occurred) is returned
 // as the result of the function call.