WIP.

cmd/migrate/create.go

@@ -14,7 +14,6 @@ import (
 var createCmd = &cobra.Command{
 	Use:   "create [flags] 'migration name'",
 	Short: "Create a new schema migration",
-	Long:  `TODO`,
 	Args:  cobra.ExactArgs(1),
 	RunE:  create,
 }

cmd/migrate/describe.go

@@ -12,7 +12,6 @@ import (
 var describeCmd = &cobra.Command{
 	Use:   "describe",
 	Short: "Describe the current database schema",
-	Long:  `TODO`,
 	RunE:  describe,
 }
 

cmd/migrate/drift.go

@@ -12,8 +12,7 @@ import (
 
 var driftCmd = &cobra.Command{
 	Use:   "drift",
-	Short: "TODO",
-	Long:  `TODO`,
+	Short: "Compare the current database schema against the expected schema",
 	RunE:  drift,
 }
 

cmd/migrate/main.go

@@ -17,7 +17,6 @@ func main() {
 var rootCmd = &cobra.Command{
 	Use:   "migrate",
 	Short: "Manage and execute Postgres schema migrations",
-	Long:  `TODO`,
 }
 
 var (
@@ -27,7 +26,12 @@ var (
 )
 
 func init() {
-	rootCmd.PersistentFlags().StringVarP(&migrationDirectory, "dir", "d", "migrations", `TODO`)
+	rootCmd.PersistentFlags().StringVarP(
+		&migrationDirectory,
+		"dir", "d",
+		"migrations",
+		"The directory where schema migrations are defined",
+	)
 }
 
 func dial() (pgutil.DB, error) {

cmd/migrate/state.go

@@ -10,7 +10,6 @@ import (
 var stateCmd = &cobra.Command{
 	Use:   "state",
 	Short: "Display the current state of the database schema",
-	Long:  `TODO`,
 	RunE:  state,
 }
 

cmd/migrate/undo.go

@@ -0,0 +1,34 @@
+package main
+
+import (
+	"context"
+	"fmt"
+	"strconv"
+
+	"github.com/spf13/cobra"
+)
+
+var undoCmd = &cobra.Command{
+	Use:   "undo [migration_id]",
+	Short: "Undo migrations up to and including the specified migration ID",
+	Args:  cobra.ExactArgs(1),
+	RunE:  undo,
+}
+
+func init() {
+	rootCmd.AddCommand(undoCmd)
+}
+
+func undo(cmd *cobra.Command, args []string) error {
+	migrationID, err := strconv.Atoi(args[0])
+	if err != nil {
+		return fmt.Errorf("invalid migration ID: %v", err)
+	}
+
+	runner, err := runner()
+	if err != nil {
+		return err
+	}
+
+	return runner.Undo(context.Background(), migrationID)
+}

cmd/migrate/up.go

@@ -9,7 +9,6 @@ import (
 var upCmd = &cobra.Command{
 	Use:   "up",
 	Short: "Run all schema migrations",
-	Long:  `TODO`,
 	RunE:  up,
 }