fix: allow specifying empty migrations (#21)

Author: bcho

fixture_test.go

@@ -294,3 +294,82 @@ func createTestContextWithRSATokenAuth(t testing.TB) *TestContext {
 		authTokenString,
 	)
 }
+
+type MigrationTestContext struct {
+	migrator  *dbMigrator
+	db        *sqlx.DB
+	cleanUpDB func(t testing.TB)
+}
+
+func (mtc *MigrationTestContext) Migrator() *dbMigrator {
+	return mtc.migrator
+}
+
+func (mtc *MigrationTestContext) CleanUp(t testing.TB) {
+	if mtc.cleanUpDB != nil {
+		mtc.cleanUpDB(t)
+	}
+}
+
+func NewMigrationTestContext(
+	t testing.TB,
+	migrations map[string]string,
+) *MigrationTestContext {
+	t.Log("creating test dir")
+	dir, err := os.MkdirTemp("", "sqlite-rest-test")
+	if err != nil {
+		t.Fatal(err)
+		return nil
+	}
+
+	migrationsDir := filepath.Join(dir, "migrations")
+	if err := os.MkdirAll(migrationsDir, 0755); err != nil {
+		t.Fatal(err)
+		return nil
+	}
+
+	t.Log("writing migrations")
+	for filename, content := range migrations {
+		p := filepath.Join(migrationsDir, filename)
+		if err := os.WriteFile(p, []byte(content), 0644); err != nil {
+			t.Fatal(err)
+			return nil
+		}
+	}
+
+	t.Log("craeting in-memory db")
+	db, err := sqlx.Open("sqlite3", "")
+	if err != nil {
+		t.Fatal(err)
+		return nil
+	}
+
+	t.Log("creating migrator")
+	migratorOpts := &MigrateOptions{
+		Logger:    createTestLogger(t).WithName("test"),
+		DB:        db.DB,
+		SourceDIR: migrationsDir,
+	}
+
+	migrator, err := NewMigrator(migratorOpts)
+	if err != nil {
+		t.Fatal(err)
+		return nil
+	}
+
+	return &MigrationTestContext{
+		migrator: migrator,
+		db:       db,
+		cleanUpDB: func(t testing.TB) {
+			if err := db.Close(); err != nil {
+				t.Errorf("closing in-memory db: %s", err)
+				return
+			}
+
+			if err := os.RemoveAll(dir); err != nil {
+				t.Fatalf("removing test dir %q: %s", dir, err)
+				return
+			}
+		},
+	}
+}

integration_migrate_test.go

@@ -0,0 +1,54 @@
+package main
+
+import (
+	"context"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestMigration(t *testing.T) {
+	t.Run("empty migrations", func(t *testing.T) {
+		tc := NewMigrationTestContext(t, nil)
+		defer tc.CleanUp(t)
+
+		ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+		defer cancel()
+
+		err := tc.Migrator().Up(ctx)
+		assert.NoError(t, err)
+	})
+
+	t.Run("apply migrations", func(t *testing.T) {
+		tc := NewMigrationTestContext(t, map[string]string{
+			"1_test.up.sql":   `create table test (id int);`,
+			"1_test.down.sql": `drop table test;`,
+		})
+		defer tc.CleanUp(t)
+
+		ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+		defer cancel()
+
+		err := tc.Migrator().Up(ctx)
+		assert.NoError(t, err)
+
+		t.Log("rerunning migrations")
+		err = tc.Migrator().Up(ctx)
+		assert.NoError(t, err)
+	})
+
+	t.Run("failed migrations", func(t *testing.T) {
+		tc := NewMigrationTestContext(t, map[string]string{
+			"1_test.up.sql":   `create table test invalid sql;`,
+			"1_test.down.sql": `drop table test;`,
+		})
+		defer tc.CleanUp(t)
+
+		ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+		defer cancel()
+
+		err := tc.Migrator().Up(ctx)
+		assert.Error(t, err)
+	})
+}

migrate.go

@@ -5,6 +5,7 @@ import (
 	"database/sql"
 	"errors"
 	"fmt"
+	"io/fs"
 	"os"
 	"path/filepath"
 
@@ -112,7 +113,6 @@ func NewMigrator(opts *MigrateOptions) (*dbMigrator, error) {
 	if err != nil {
 		return nil, err
 	}
-	fmt.Println("file://" + opts.SourceDIR)
 	migrator, err := migrate.NewWithDatabaseInstance(
 		"file://"+opts.SourceDIR,
 		"sqlite3", driver,
@@ -134,17 +134,27 @@ func (m *dbMigrator) Up(ctx context.Context) error {
 	logger.Info("applying operation")
 
 	err := m.migrator.Up()
+	if err == nil {
+		logger.Info("applied operation")
+
+		return nil
+	}
+
 	if errors.Is(err, migrate.ErrNoChange) {
 		// no update
-		err = nil
 		logger.V(8).Info("no pending migrations")
+		return nil
 	}
-	if err != nil {
 
-		logger.Error(err, "failed to apply operation")
-		return fmt.Errorf("up: %w", err)
+	var pathErr *fs.PathError
+	if errors.As(err, &pathErr) {
+		// no migrations set
+		if pathErr.Op == "first" && errors.Is(pathErr.Err, fs.ErrNotExist) {
+			logger.Info("no migrations to apply")
+			return nil
+		}
 	}
-	logger.Info("applied operation")
 
-	return nil
+	logger.Error(err, "failed to apply operation")
+	return fmt.Errorf("up: %w", err)
 }