From e70aa4675b0251729b08a41e96679fc993ccee4c Mon Sep 17 00:00:00 2001
From: Elijah Duffy <elijah@thatoneguy.ca>
Date: Mon, 9 Jun 2025 13:37:25 -0700
Subject: [PATCH] add support for config generator function

---
 migrate.go | 59 +++++++++++++++++++++++++++++++++++-------------------
 1 file changed, 38 insertions(+), 21 deletions(-)

diff --git a/migrate.go b/migrate.go
index 361c7cb..d59ca8d 100644
--- a/migrate.go
+++ b/migrate.go
@@ -47,7 +47,9 @@ var (
 	Migration *goose.Provider
 
 	// migrationsConfig stores the configuration for the migrations module.
-	migrationsConfig MigrationOpts
+	migrationsConfig *MigrationOpts
+
+	migrationsConfigFn func(*app.Module) *MigrationOpts
 
 	// migrationsModule is the singleton module instance for the migrations subsystem.
 	migrationsModule *app.Module
@@ -72,28 +74,27 @@ var (
 )
 
 // MigrationsConfig returns the current configuration for the migrations module.
-func MigrationsConfig() MigrationOpts {
+func MigrationsConfig() *MigrationOpts {
 	migrationsModule.RequireLoaded() // ensure the migrations module is loaded
+	// Since the module is loaded (setup is called), we can safely return the config.
 	return migrationsConfig
 }
 
 // ModuleMigrations returns the migrations module with the provided configuration.
 func ModuleMigrations(cfg MigrationOpts) *app.Module {
+	return ModuleMigrationsFn(func(_ *app.Module) *MigrationOpts {
+		return &cfg
+	})
+}
+
+// ModuleMigrationsFn returns the migration module with the provided configuration function.
+func ModuleMigrationsFn(cfgFn func(*app.Module) *MigrationOpts) *app.Module {
 	if migrationsModule != nil {
-		panic("ModuleMigrations initialized multiple times")
+		panic("ModuleMigrationsFn initialized multiple times")
 	}
 
-	if cfg.SQLO == nil {
-		panic("Migration SQL handle (SQLO) must be set in the configuration")
-	}
-	if cfg.BasePath == "" {
-		cfg.BasePath = "." // default base path if not set
-	}
-	if cfg.FS == nil {
-		panic("Migration filesystem (FS) must be set in the configuration")
-	}
-
-	migrationsConfig = cfg // store configuration at package level
+	// Store configuration function at package level
+	migrationsConfigFn = cfgFn
 
 	migrationsModule = app.NewModule(ModuleMigrationsName, app.ModuleOpts{
 		Setup:   setupMigrations,
@@ -139,23 +140,39 @@ func ModuleAutoMigrate(enabled bool) *app.Module {
 }
 
 // setupMigrations initializes the goose migration provider.
-func setupMigrations(_ *app.Module) error {
-	var err error
+func setupMigrations(mod *app.Module) error {
+	if migrationsConfigFn == nil {
+		panic("Migrations configuration is not set")
+	}
 
-	if err := goose.SetDialect(string(migrationsConfig.Dialect)); err != nil {
-		migrationsModule.Logger().Error("Couldn't set database dialect for goose", "err", err)
+	cfg := migrationsConfigFn(mod)
+	if cfg.SQLO == nil {
+		panic("Migration SQL handle (SQLO) must be set in the configuration")
+	}
+	if cfg.BasePath == "" {
+		cfg.BasePath = "." // default base path if not set
+	}
+	if cfg.FS == nil {
+		panic("Migration filesystem (FS) must be set in the configuration")
+	}
+	migrationsConfig = cfg // store the configuration at package level
+
+	var err error
+	if err := goose.SetDialect(string(cfg.Dialect)); err != nil {
+		mod.Logger().Error("Couldn't set database dialect for goose", "err", err)
 		return err
 	}
 
 	// Set base filesystem for goose migrations
-	goose.SetBaseFS(migrationsConfig.FS)
+	goose.SetBaseFS(cfg.FS)
 
 	// Initialize the goose migration provider
-	Migration, err = goose.NewProvider(migrationsConfig.Dialect, migrationsConfig.SQLO(), migrationsConfig.FS)
+	Migration, err = goose.NewProvider(cfg.Dialect, cfg.SQLO(), cfg.FS)
 	if err != nil {
-		migrationsModule.Logger().Error("Couldn't initialize goose migration provider", "err", err)
+		mod.Logger().Error("Couldn't initialize goose migration provider", "err", err)
 		return err
 	}
+	mod.Logger().Info("Goose migration provider initialized", "dialect", cfg.Dialect, "basePath", cfg.BasePath, "fs", cfg.FS)
 
 	return nil
 }