Prevent incorrect Tigris configuration in Rails scanner for GitHub integration

scanner/rails.go

@@ -136,10 +136,6 @@ func configureRails(sourceDir string, config *ScannerConfig) (*SourceInfo, error
 		// sqlite (detected from existing Dockerfile)
 		s.DatabaseDesired = DatabaseKindSqlite
 		s.SkipDatabase = true
-		// Only request object storage if not skipping extensions (for litestream replication)
-		if os.Getenv("SKIP_EXTENSIONS") == "" {
-			s.ObjectStorageDesired = true
-		}
 	} else if checksPass(sourceDir, dirContains("config/database.yml", "adapter.*sqlite")) {
 		// sqlite (detected from database.yml)
 		s.DatabaseDesired = DatabaseKindSqlite
@@ -198,7 +194,11 @@ func configureRails(sourceDir string, config *ScannerConfig) (*SourceInfo, error
 	if checksPass(sourceDir, dirContains("Gemfile", "aws-sdk-s3")) || checksPass(sourceDir, dirContains("Gemfile.lock", "aws-sdk-s3")) {
 		s.ObjectStorageDesired = true
 	} else if checksPass(sourceDir+"/db/migrate", dirContains("*.rb", ":active_storage_attachments")) {
-		s.ObjectStorageDesired = true
+		// Rails apps may keep old Active Storage migrations around even when
+		// runtime storage is explicitly local. Avoid a false positive in that case.
+		if !railsProductionActiveStorageIsLocal(sourceDir) {
+			s.ObjectStorageDesired = true
+		}
 	} else if checksPass(sourceDir+"/config", fileExists("storage.yml")) {
 		cfgMap := map[string]any{}
 		buf, err := os.ReadFile(path.Join(sourceDir, "config", "storage.yml"))
@@ -209,8 +209,13 @@ func configureRails(sourceDir string, config *ScannerConfig) (*SourceInfo, error
 
 		if err == nil {
 			for _, v := range cfgMap {
-				submap, ok := v.(map[interface{}]interface{})
-				if ok {
+				switch submap := v.(type) {
+				case map[interface{}]interface{}:
+					service, ok := submap["service"].(string)
+					if ok && service == "S3" {
+						s.ObjectStorageDesired = true
+					}
+				case map[string]interface{}:
 					service, ok := submap["service"].(string)
 					if ok && service == "S3" {
 						s.ObjectStorageDesired = true
@@ -334,6 +339,22 @@ Once ready: run 'fly deploy' to deploy your Rails app.
 	return s, nil
 }
 
+func railsProductionActiveStorageIsLocal(sourceDir string) bool {
+	buf, err := os.ReadFile(path.Join(sourceDir, "config", "environments", "production.rb"))
+	if err != nil {
+		return false
+	}
+
+	prodEnv := string(buf)
+	re := regexp.MustCompile(`(?m)config\.active_storage\.service\s*=\s*:(local|test)\b`)
+	if re.MatchString(prodEnv) {
+		return true
+	}
+
+	re = regexp.MustCompile(`(?m)config\.active_storage\.service\s*=\s*["'](local|test)["']\b`)
+	return re.MatchString(prodEnv)
+}
+
 func RailsCallback(appName string, srcInfo *SourceInfo, plan *plan.LaunchPlan, flags []string) error {
 	// Overall strategy: Install and use the dockerfile-rails gem to generate a Dockerfile.
 	//

scanner/rails_object_storage_detection_test.go

@@ -0,0 +1,166 @@
+package scanner
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestRailsObjectStorageDetection(t *testing.T) {
+	t.Run("migration plus local production storage does not request object storage", func(t *testing.T) {
+		dir := t.TempDir()
+		writeRailsScannerFixture(t, dir, "config.active_storage.service = :local\n")
+		writeActiveStorageMigration(t, dir)
+
+		originalDir, err := os.Getwd()
+		require.NoError(t, err)
+		defer os.Chdir(originalDir)
+		require.NoError(t, os.Chdir(dir))
+
+		si, err := configureRails(dir, &ScannerConfig{})
+		require.NoError(t, err)
+		require.NotNil(t, si)
+		assert.False(t, si.ObjectStorageDesired)
+	})
+
+	t.Run("migration plus non-local production storage requests object storage", func(t *testing.T) {
+		dir := t.TempDir()
+		writeRailsScannerFixture(t, dir, "config.active_storage.service = :amazon\n")
+		writeActiveStorageMigration(t, dir)
+
+		originalDir, err := os.Getwd()
+		require.NoError(t, err)
+		defer os.Chdir(originalDir)
+		require.NoError(t, os.Chdir(dir))
+
+		si, err := configureRails(dir, &ScannerConfig{})
+		require.NoError(t, err)
+		require.NotNil(t, si)
+		assert.True(t, si.ObjectStorageDesired)
+	})
+
+	t.Run("sqlite package in Dockerfile alone does not request object storage", func(t *testing.T) {
+		dir := t.TempDir()
+		writeRailsScannerFixture(t, dir, "config.active_storage.service = :local\n")
+
+		require.NoError(t, os.WriteFile(
+			filepath.Join(dir, "Dockerfile"),
+			[]byte("FROM ruby:3.3-slim\nRUN apt-get update -qq && apt-get install --no-install-recommends -y sqlite3\nEXPOSE 80\n"),
+			0644,
+		))
+
+		originalDir, err := os.Getwd()
+		require.NoError(t, err)
+		defer os.Chdir(originalDir)
+		require.NoError(t, os.Chdir(dir))
+
+		si, err := configureRails(dir, &ScannerConfig{})
+		require.NoError(t, err)
+		require.NotNil(t, si)
+		assert.False(t, si.ObjectStorageDesired)
+	})
+
+	t.Run("commented S3 entries in storage.yml do not request object storage", func(t *testing.T) {
+		dir := t.TempDir()
+		writeRailsScannerFixture(t, dir, "config.active_storage.service = :local\n")
+
+		require.NoError(t, os.WriteFile(
+			filepath.Join(dir, "config", "storage.yml"),
+			[]byte("local:\n  service: Disk\n\n# amazon:\n#   service: S3\n#   bucket: foo\n"),
+			0644,
+		))
+
+		originalDir, err := os.Getwd()
+		require.NoError(t, err)
+		defer os.Chdir(originalDir)
+		require.NoError(t, os.Chdir(dir))
+
+		si, err := configureRails(dir, &ScannerConfig{})
+		require.NoError(t, err)
+		require.NotNil(t, si)
+		assert.False(t, si.ObjectStorageDesired)
+	})
+
+	t.Run("active S3 service in storage.yml requests object storage", func(t *testing.T) {
+		dir := t.TempDir()
+		writeRailsScannerFixture(t, dir, "config.active_storage.service = :local\n")
+
+		require.NoError(t, os.WriteFile(
+			filepath.Join(dir, "config", "storage.yml"),
+			[]byte("amazon:\n  service: S3\n  bucket: foo\n"),
+			0644,
+		))
+
+		originalDir, err := os.Getwd()
+		require.NoError(t, err)
+		defer os.Chdir(originalDir)
+		require.NoError(t, os.Chdir(dir))
+
+		si, err := configureRails(dir, &ScannerConfig{})
+		require.NoError(t, err)
+		require.NotNil(t, si)
+		assert.True(t, si.ObjectStorageDesired)
+	})
+}
+
+func writeRailsScannerFixture(t *testing.T, dir string, prodStorageLine string) {
+	t.Helper()
+
+	require.NoError(t, os.MkdirAll(filepath.Join(dir, "config", "environments"), 0755))
+	require.NoError(t, os.MkdirAll(filepath.Join(dir, "db", "migrate"), 0755))
+
+	require.NoError(t, os.WriteFile(
+		filepath.Join(dir, "Gemfile"),
+		[]byte("source 'https://rubygems.org'\ngem 'rails', '~> 8.0'\n"),
+		0644,
+	))
+	require.NoError(t, os.WriteFile(
+		filepath.Join(dir, "Gemfile.lock"),
+		[]byte("GEM\n  specs:\n    rails (8.0.0)\n"),
+		0644,
+	))
+	require.NoError(t, os.WriteFile(
+		filepath.Join(dir, "config.ru"),
+		[]byte("require_relative 'config/environment'\nrun Rails.application\n"),
+		0644,
+	))
+
+	require.NoError(t, os.WriteFile(
+		filepath.Join(dir, "Dockerfile"),
+		[]byte("FROM ruby:3.3-slim\nEXPOSE 80\n"),
+		0644,
+	))
+
+	require.NoError(t, os.WriteFile(
+		filepath.Join(dir, "config", "storage.yml"),
+		[]byte("local:\n  service: Disk\n"),
+		0644,
+	))
+
+	for _, env := range []string{"development", "test"} {
+		require.NoError(t, os.WriteFile(
+			filepath.Join(dir, "config", "environments", env+".rb"),
+			[]byte("Rails.application.configure do\n  config.active_storage.service = :local\nend\n"),
+			0644,
+		))
+	}
+
+	require.NoError(t, os.WriteFile(
+		filepath.Join(dir, "config", "environments", "production.rb"),
+		[]byte("Rails.application.configure do\n  "+prodStorageLine+"end\n"),
+		0644,
+	))
+}
+
+func writeActiveStorageMigration(t *testing.T, dir string) {
+	t.Helper()
+
+	require.NoError(t, os.WriteFile(
+		filepath.Join(dir, "db", "migrate", "20250101000000_create_active_storage_tables.rb"),
+		[]byte("class CreateActiveStorageTables < ActiveRecord::Migration[7.1]\n  def change\n    create_table :active_storage_attachments do |t|\n      t.string :name\n    end\n  end\nend\n"),
+		0644,
+	))
+}