Bare minimum db schema

Author: DavidHuie

db.go

@@ -3,12 +3,12 @@ package gomigrate
 type Migratable interface {
 	SelectMigrationTableSql() string
 	CreateMigrationTableSql() string
-	MigrationStatusSql() string
+	GetMigrationSql() string
 	MigrationLogInsertSql() string
-	MigrationLogUpdateSql() string
+	MigrationLogDeleteSql() string
 }
 
-// POSTGRESQL
+// POSTGRES
 
 type Postgres struct{}
 
@@ -19,22 +19,20 @@ func (p Postgres) SelectMigrationTableSql() string {
 func (p Postgres) CreateMigrationTableSql() string {
 	return `CREATE TABLE gomigrate (
                   id           SERIAL       PRIMARY KEY,
-                  migration_id INT          UNIQUE NOT NULL,
-                  name         VARCHAR(100) UNIQUE NOT NULL,
-                  status       INT          NOT NULL
+                  migration_id BIGINT       UNIQUE NOT NULL
                 )`
 }
 
-func (p Postgres) MigrationStatusSql() string {
-	return "SELECT status FROM gomigrate WHERE name = $1"
+func (p Postgres) GetMigrationSql() string {
+	return `SELECT migration_id FROM gomigrate WHERE migration_id = $1`
 }
 
 func (p Postgres) MigrationLogInsertSql() string {
-	return "INSERT INTO gomigrate (migration_id, name, status) values ($1, $2, $3)"
+	return "INSERT INTO gomigrate (migration_id) values ($1)"
 }
 
-func (p Postgres) MigrationLogUpdateSql() string {
-	return "UPDATE gomigrate SET status = $1 WHERE migration_id = $2"
+func (p Postgres) MigrationLogDeleteSql() string {
+	return "DELETE FROM gomigrate WHERE migration_id = $1"
 }
 
 // MYSQL
@@ -48,21 +46,19 @@ func (m Mysql) SelectMigrationTableSql() string {
 func (m Mysql) CreateMigrationTableSql() string {
 	return `CREATE TABLE gomigrate (
                   id           INT          NOT NULL AUTO_INCREMENT,
-                  migration_id INT          NOT NULL UNIQUE,
-                  name         VARCHAR(100) NOT NULL UNIQUE,
-                  status       INT          NOT NULL,
+                  migration_id BIGINT       NOT NULL UNIQUE,
                   PRIMARY KEY (id)
                 ) ENGINE=MyISAM`
 }
 
-func (m Mysql) MigrationStatusSql() string {
-	return "SELECT status FROM gomigrate WHERE name = ?"
+func (m Mysql) GetMigrationSql() string {
+	return `SELECT migration_id FROM gomigrate WHERE migration_id = ?`
 }
 
 func (m Mysql) MigrationLogInsertSql() string {
-	return "INSERT INTO gomigrate (migration_id, name, status) values (?, ?, ?)"
+	return "INSERT INTO gomigrate (migration_id) values (?)"
 }
 
-func (m Mysql) MigrationLogUpdateSql() string {
-	return "UPDATE gomigrate SET status = ? WHERE migration_id = ?"
+func (m Mysql) MigrationLogDeleteSql() string {
+	return "DELETE FROM gomigrate WHERE migration_id = ?"
 }

gomigrate.go

@@ -155,7 +155,12 @@ func (m *Migrator) fetchMigrations() error {
 // migration.
 func (m *Migrator) getMigrationStatuses() error {
 	for _, migration := range m.migrations {
-		rows, err := m.DB.Query(m.dbAdapter.MigrationStatusSql(), migration.Name)
+		row := m.DB.QueryRow(m.dbAdapter.GetMigrationSql(), migration.Id)
+		var mid uint64
+		err := row.Scan(&mid)
+		if err == sql.ErrNoRows {
+			continue
+		}
 		if err != nil {
 			log.Printf(
 				"Error getting migration status for %s: %v",
@@ -164,20 +169,7 @@ func (m *Migrator) getMigrationStatuses() error {
 			)
 			return err
 		}
-		for rows.Next() {
-			var status int
-			err := rows.Scan(&status)
-			if err != nil {
-				log.Printf("Error getting migration status: %v", err)
-				return err
-			}
-			migration.Status = status
-			log.Printf(
-				"Migration %s found with status: %v",
-				migration.Name,
-				status,
-			)
-		}
+		migration.Status = Active
 	}
 	return nil
 }
@@ -230,8 +222,6 @@ func (m *Migrator) Migrate() error {
 		_, err = transaction.Exec(
 			m.dbAdapter.MigrationLogInsertSql(),
 			migration.Id,
-			migration.Name,
-			Active,
 		)
 		if err != nil {
 			log.Printf("Error logging migration: %v", err)
@@ -288,8 +278,7 @@ func (m *Migrator) Rollback() error {
 
 	// Change the status in the migrations table.
 	_, err = transaction.Exec(
-		m.dbAdapter.MigrationLogUpdateSql(),
-		Inactive,
+		m.dbAdapter.MigrationLogDeleteSql(),
 		lastMigration.Id,
 	)
 	if err != nil {

gomigrate_test.go

@@ -58,26 +58,22 @@ func TestCreatingMigratorWhenTableExists(t *testing.T) {
 	if err != nil {
 		t.Error(err)
 	}
-	_, err = db.Exec(adapter.MigrationLogInsertSql(), 123, "my_test", Active)
+	_, err = db.Exec(adapter.MigrationLogInsertSql(), 123)
 	if err != nil {
 		t.Error(err)
 	}
 
 	GetMigrator("test1")
 
 	// Check that our row is still present.
-	row := db.QueryRow("select name, status from gomigrate")
-	var name string
-	var status int
-	err = row.Scan(&name, &status)
+	row := db.QueryRow("select migration_id from gomigrate")
+	var id uint64
+	err = row.Scan(&id)
 	if err != nil {
 		t.Error(err)
 	}
-	if name != "my_test" {
-		t.Error("Invalid name found in database")
-	}
-	if status != Active {
-		t.Error("Invalid status found in database")
+	if id != 123 {
+		t.Error("Invalid id found in database")
 	}
 	cleanup()
 }
@@ -103,8 +99,8 @@ func TestMigrationAndRollback(t *testing.T) {
 	}
 	// Ensure that the migrate status is correct.
 	row = db.QueryRow(
-		adapter.MigrationStatusSql(),
-		"test",
+		adapter.GetMigrationSql(),
+		1,
 	)
 	var status int
 	if err := row.Scan(&status); err != nil {
@@ -128,16 +124,16 @@ func TestMigrationAndRollback(t *testing.T) {
 		t.Errorf("Migration table should be deleted")
 	}
 
-	// Ensure that the migrate status is correct.
+	// Ensure that the migration log is missing.
 	row = db.QueryRow(
-		adapter.MigrationStatusSql(),
-		"test",
+		adapter.GetMigrationSql(),
+		1,
 	)
-	if err := row.Scan(&status); err != nil {
+	if err := row.Scan(&status); err != sql.ErrNoRows {
 		t.Error(err)
 	}
-	if status != Inactive || m.migrations[1].Status != Inactive {
-		t.Errorf("Invalid status for migration, %v", status)
+	if m.migrations[1].Status != Inactive {
+		t.Errorf("Invalid status for migration, %v", m.migrations[1].Status)
 	}
 
 	cleanup()

migration.go

@@ -11,12 +11,10 @@ const (
 // Holds configuration information for a given migration.
 type Migration struct {
 	DownPath string
+	Id       uint64
 	Name     string
 	Status   int
 	UpPath   string
-
-	// The file system identifier, not the database id.
-	Id uint64
 }
 
 // Performs a basic validation of a migration.