Add support for JSON version output

Signed-off-by: Samuel Dacanay <sam.dacanay@anchore.com>

Make json version output always verbose, cleanup struct tag

Signed-off-by: Samuel Dacanay <sam.dacanay@anchore.com>

Use camel case for json

Signed-off-by: Samuel Dacanay <sam.dacanay@anchore.com>

cmd/version.go

@@ -1,14 +1,19 @@
 package cmd
 
 import (
+	"encoding/json"
 	"fmt"
+	"os"
 
 	"github.com/anchore/syft/internal"
+
 	"github.com/anchore/syft/internal/version"
+	"github.com/anchore/syft/syft/presenter"
 	"github.com/spf13/cobra"
 )
 
 var showVerboseVersionInfo bool
+var outputFormat string
 
 var versionCmd = &cobra.Command{
 	Use:   "version",
@@ -18,22 +23,44 @@ var versionCmd = &cobra.Command{
 
 func init() {
 	versionCmd.Flags().BoolVarP(&showVerboseVersionInfo, "verbose", "v", false, "show additional version information")
-
+	versionCmd.Flags().StringVarP(&outputFormat, "output", "o", string(presenter.TextPresenter), "format to show version information (available=[text, json])")
 	rootCmd.AddCommand(versionCmd)
 }
 
 func printVersion(_ *cobra.Command, _ []string) {
 	versionInfo := version.FromBuild()
-	if showVerboseVersionInfo {
-		fmt.Println("Application:  ", internal.ApplicationName)
-		fmt.Println("Version:      ", versionInfo.Version)
-		fmt.Println("BuildDate:    ", versionInfo.BuildDate)
-		fmt.Println("GitCommit:    ", versionInfo.GitCommit)
-		fmt.Println("GitTreeState: ", versionInfo.GitTreeState)
-		fmt.Println("Platform:     ", versionInfo.Platform)
-		fmt.Println("GoVersion:    ", versionInfo.GoVersion)
-		fmt.Println("Compiler:     ", versionInfo.Compiler)
-	} else {
-		fmt.Printf("%s %s\n", internal.ApplicationName, versionInfo.Version)
+
+	switch outputFormat {
+	case "text":
+		if showVerboseVersionInfo {
+			fmt.Println("Application:  ", internal.ApplicationName)
+			fmt.Println("Version:      ", versionInfo.Version)
+			fmt.Println("BuildDate:    ", versionInfo.BuildDate)
+			fmt.Println("GitCommit:    ", versionInfo.GitCommit)
+			fmt.Println("GitTreeState: ", versionInfo.GitTreeState)
+			fmt.Println("Platform:     ", versionInfo.Platform)
+			fmt.Println("GoVersion:    ", versionInfo.GoVersion)
+			fmt.Println("Compiler:     ", versionInfo.Compiler)
+		} else {
+			fmt.Printf("%s %s\n", internal.ApplicationName, versionInfo.Version)
+		}
+	case "json":
+		enc := json.NewEncoder(os.Stdout)
+		enc.SetEscapeHTML(false)
+		enc.SetIndent("", " ")
+		err := enc.Encode(&struct {
+			version.Version
+			Application string `json:"application"`
+		}{
+			Version:     versionInfo,
+			Application: internal.ApplicationName,
+		})
+		if err != nil {
+			fmt.Printf("failed to show version information: %+v\n", err)
+			os.Exit(1)
+		}
+	default:
+		fmt.Printf("unsupported output format: %s\n", outputFormat)
+		os.Exit(1)
 	}
 }

internal/version/build.go

@@ -16,13 +16,13 @@ var platform = fmt.Sprintf("%s/%s", runtime.GOOS, runtime.GOARCH)
 
 // Version defines the application version details (generally from build information)
 type Version struct {
-	Version      string // application semantic version
-	GitCommit    string // git SHA at build-time
-	GitTreeState string // indication of git tree (either "clean" or "dirty") at build-time
-	BuildDate    string // date of the build
-	GoVersion    string // go runtime version at build-time
-	Compiler     string // compiler used at build-time
-	Platform     string // GOOS and GOARCH at build-time
+	Version      string `json:"version"`      // application semantic version
+	GitCommit    string `json:"gitCommit"`    // git SHA at build-time
+	GitTreeState string `json:"gitTreeState"` // indication of git tree (either "clean" or "dirty") at build-time
+	BuildDate    string `json:"buildDate"`    // date of the build
+	GoVersion    string `json:"goVersion"`    // go runtime version at build-time
+	Compiler     string `json:"compiler"`     // compiler used at build-time
+	Platform     string `json:"platform"`     // GOOS and GOARCH at build-time
 }
 
 // FromBuild provides all version details