From 2b54cbb95bb938e608a59c5247b343785761a3b2 Mon Sep 17 00:00:00 2001
From: Marc Cataford <mcat@riseup.net>
Date: Sat, 13 Jul 2024 23:44:04 -0400
Subject: [PATCH] refactor: use flags instead of positionals, reorganize cli
 init

---
 cobble.go | 80 ++++++++++++++++++++++++++++++-------------------------
 1 file changed, 44 insertions(+), 36 deletions(-)

diff --git a/cobble.go b/cobble.go
index d0c0c3b..298324a 100644
--- a/cobble.go
+++ b/cobble.go
@@ -23,49 +23,57 @@ func SetupDatabaseConnection(cmd *cobra.Command, args []string) {
 	cmd.SetContext(context.WithValue(cmd.Context(), "db", db))
 }
 
-var cli = &cobra.Command{
-	Use:   "cobble",
-	Short: "Cobble is a simple SQL migration utility.",
-}
+func NewCli() *cobra.Command {
+	cli := &cobra.Command{
+		Use:   "cobble",
+		Short: "Cobble is a simple SQL migration utility.",
+	}
 
-var up = &cobra.Command{
-	Use:    "up",
-	Short:  "Applies migrations",
-	PreRun: SetupDatabaseConnection,
-	Run: func(cmd *cobra.Command, args []string) {
-		db := cmd.Context().Value("db").(DB)
-		migrationRoot := args[0]
-		migrationGraph, _ := NewMigrationGraphFromDirectory(migrationRoot)
-		migrationHistory, _ := migrationGraph.GetLinearHistory()
-		for _, migration := range migrationHistory {
-			log.Printf("%s", migration.Name)
-			if err := migration.Apply(db); err != nil {
-				os.Exit(1)
+	up := &cobra.Command{
+		Use:    "up",
+		Short:  "Applies migrations",
+		PreRun: SetupDatabaseConnection,
+		Run: func(cmd *cobra.Command, args []string) {
+			db := cmd.Context().Value("db").(DB)
+			migrationRoot := args[0]
+			migrationGraph, _ := NewMigrationGraphFromDirectory(migrationRoot)
+			migrationHistory, _ := migrationGraph.GetLinearHistory()
+			for _, migration := range migrationHistory {
+				log.Printf("%s", migration.Name)
+				if err := migration.Apply(db); err != nil {
+					os.Exit(1)
+				}
 			}
-		}
-	},
-}
+		},
+	}
 
-var inspect = &cobra.Command{
-	Use:   "inspect",
-	Short: "Prints the nth migration in the history",
-	Run: func(cmd *cobra.Command, args []string) {
-		migrationRoot := args[0]
-		migrationIndex, _ := strconv.Atoi(args[1])
+	inspect := &cobra.Command{
+		Use:   "inspect",
+		Short: "Prints the nth migration in the history",
+		Run: func(cmd *cobra.Command, args []string) {
+			migrationRoot, _ := cmd.Flags().GetString("root")
+			migrationIndex, _ := cmd.Flags().GetInt("index")
 
-		migrationGraph, _ := NewMigrationGraphFromDirectory(migrationRoot)
-		migrationHistory, _ := migrationGraph.GetLinearHistory()
-		migration := migrationHistory[migrationIndex]
-		sql, _ := migration.Sql()
-		fmt.Printf("%s:\n%s", migration.Name, sql)
-	},
-}
-
-func main() {
+			migrationGraph, _ := NewMigrationGraphFromDirectory(migrationRoot)
+			migrationHistory, _ := migrationGraph.GetLinearHistory()
+			migration := migrationHistory[migrationIndex]
+			sql, _ := migration.Sql()
+			fmt.Printf("%s:\n%s", migration.Name, sql)
+		},
+	}
 	cli.AddCommand(up)
 	cli.AddCommand(inspect)
 
-	if err := cli.Execute(); err != nil {
+	cli.PersistentFlags().StringP("root", "r", "./migrations", "Root directory where migration files live.")
+	inspect.PersistentFlags().IntP("index", "i", 0, "Zero-based index of the migration to target.")
+
+	inspect.MarkFlagRequired("index")
+
+	return cli
+}
+
+func main() {
+	if err := NewCli().Execute(); err != nil {
 		log.Fatal(err)
 		os.Exit(1)
 	}