Allow migrating up and down

polyculeconnect/cmd/db/migrate.go

@@ -2,6 +2,7 @@ package db
 
 import (
 	"fmt"
+	"strconv"
 
 	"git.faercol.me/faercol/polyculeconnect/polyculeconnect/cmd/utils"
 	"git.faercol.me/faercol/polyculeconnect/polyculeconnect/config"
@@ -19,13 +20,40 @@ var migrateCmd = &cobra.Command{
 	Long:  `Run the database migrations.`,
 	Run: func(cmd *cobra.Command, args []string) {
 		conf := utils.InitConfig("")
-		if err := runMigrations(conf); err != nil {
+		up, nbSteps := parseArgs(args)
+		if err := runMigrations(conf, up, nbSteps); err != nil {
 			utils.Failf("Failed to run migrations: %s", err.Error())
 		}
 	},
 }
 
-func runMigrations(conf *config.AppConfig) error {
+func parseArgs(args []string) (bool, int) {
+	if len(args) == 0 {
+		return true, 0
+	}
+	var actionUp bool
+	switch args[0] {
+	case "up":
+		actionUp = true
+	case "down":
+		actionUp = false
+	default:
+		actionUp = true
+	}
+
+	nbSteps := 0
+	if len(args) > 1 {
+		var err error
+		nbSteps, err = strconv.Atoi(args[1])
+		if err != nil {
+			return actionUp, 0
+		}
+	}
+
+	return actionUp, nbSteps
+}
+
+func runMigrations(conf *config.AppConfig, up bool, nbSteps int) error {
 	storage, err := db.New(*conf)
 	if err != nil {
 		return fmt.Errorf("failed to connect to db: %w", err)
@@ -39,10 +67,18 @@ func runMigrations(conf *config.AppConfig) error {
 	if err != nil {
 		return fmt.Errorf("failed to init migrator: %w", err)
 	}
-	if err := m.Up(); err != nil {
+
-		return fmt.Errorf("failed to run migrations: %w", err)
+	if nbSteps > 0 {
+		multiplier := 1
+		if !up {
+			multiplier = -1
+		}
+		return m.Steps(multiplier * nbSteps)
 	}
-	return nil
+	if up {
+		return m.Up()
+	}
+	return m.Down()
 }
 
 func init() {