Add version subcommand to stellar-etl CLI (#347)

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: leighmcculloch <351529+leighmcculloch@users.noreply.github.com>

Author: Copilot

cmd/version.go

@@ -0,0 +1,42 @@
+package cmd
+
+import (
+	"fmt"
+	"io"
+	"runtime/debug"
+
+	"github.com/spf13/cobra"
+)
+
+var versionCmd = &cobra.Command{
+	Use:   "version",
+	Short: "Display version information",
+	Long:  `Display the version of stellar-etl and the versions of XDR libs.`,
+	Run: func(cmd *cobra.Command, args []string) {
+		buildInfo, ok := debug.ReadBuildInfo()
+		if !ok {
+			fmt.Fprintf(cmd.OutOrStdout(), "stellar-etl (unknown)\n")
+			return
+		}
+		fmt.Fprintf(cmd.OutOrStdout(), "stellar-etl %s\n", buildInfo.Main.Version)
+
+		// Find and display versions of libs containing XDR
+		printDepVersion(cmd.OutOrStdout(), buildInfo, "github.com/stellar/go")
+		printDepVersion(cmd.OutOrStdout(), buildInfo, "github.com/stellar/go-stellar-xdr-json")
+	},
+}
+
+func printDepVersion(out io.Writer, buildInfo *debug.BuildInfo, name string) {
+	version := "(unknown)"
+	for _, dep := range buildInfo.Deps {
+		if dep.Path == name {
+			version = dep.Version
+			break
+		}
+	}
+	fmt.Fprintf(out, "%s %s\n", name, version)
+}
+
+func init() {
+	rootCmd.AddCommand(versionCmd)
+}

cmd/version_test.go

@@ -0,0 +1,25 @@
+package cmd
+
+import (
+	"bytes"
+	"testing"
+
+	"github.com/spf13/cobra"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestVersionCommand(t *testing.T) {
+	cmd := &cobra.Command{}
+	cmd.AddCommand(versionCmd)
+	out := new(bytes.Buffer)
+	cmd.SetOut(out)
+	cmd.SetArgs([]string{"version"})
+	err := cmd.Execute()
+	require.NoError(t, err)
+
+	outStr := out.String()
+	assert.Contains(t, outStr, "stellar-etl")
+	assert.Contains(t, outStr, "github.com/stellar/go")
+	assert.Contains(t, outStr, "github.com/stellar/go-stellar-xdr-json")
+}