Create simple version command (#174)

Author: bplunkett-stripe

README.md

@@ -91,12 +91,12 @@ $ pg-schema-diff plan --dsn "postgres://postgres:postgres@localhost:5432/postgre
 # Install
 ## CLI
 ```bash
-go install github.com/stripe/pg-schema-diff/cmd/pg-schema-diff
+go install github.com/stripe/pg-schema-diff/cmd/pg-schema-diff@latest
 ```
 
 ## Library
 ```bash
-go get -u github.com/stripe/pg-schema-diff
+go get -u github.com/stripe/pg-schema-diff@latest
 ```
 # Using CLI
 ## 1. Apply schema to fresh database

cmd/pg-schema-diff/main.go

@@ -15,6 +15,7 @@ var rootCmd = &cobra.Command{
 func init() {
 	rootCmd.AddCommand(buildPlanCmd())
 	rootCmd.AddCommand(buildApplyCmd())
+	rootCmd.AddCommand(buildVersionCmd())
 }
 
 func main() {

cmd/pg-schema-diff/version_cmd.go

@@ -0,0 +1,25 @@
+package main
+
+import (
+	"fmt"
+	"runtime/debug"
+
+	"github.com/spf13/cobra"
+)
+
+func buildVersionCmd() *cobra.Command {
+	cmd := &cobra.Command{
+		Use:   "version",
+		Short: "Get the version of pg-schema-diff",
+	}
+	cmd.RunE = func(_ *cobra.Command, _ []string) error {
+		buildInfo, ok := debug.ReadBuildInfo()
+		if !ok {
+			return fmt.Errorf("build information not available")
+		}
+		fmt.Printf("version=%s\n", buildInfo.Main.Version)
+
+		return nil
+	}
+	return cmd
+}