Add savepoint support for transactions

lib/dialects/abstract/query-generator.js

@@ -1008,7 +1008,18 @@ module.exports = (function() {
       return 'SET autocommit = ' + (!!value ? 1 : 0) + ';';
     },
 
-    setIsolationLevelQuery: function(value) {
+    /**
+     * Returns a query that sets the transaction isolation level.
+     *
+     * @param  {String} value   The isolation level.
+     * @param  {Object} options An object with options.
+     * @return {String}         The generated sql query.
+     */
+    setIsolationLevelQuery: function(value, options) {
+      if (options.parent) {
+        return;
+      }
+
       return 'SET SESSION TRANSACTION ISOLATION LEVEL ' + value + ';';
     },
 
@@ -1019,6 +1030,10 @@ module.exports = (function() {
      * @return {String}         The generated sql query.
      */
     startTransactionQuery: function(options) {
+      if (options.parent) {
+        return 'SAVEPOINT ' + this.quoteIdentifier(options.parent.id) + ';';
+      }
+
       return 'START TRANSACTION;';
     },
 
@@ -1029,6 +1044,10 @@ module.exports = (function() {
      * @return {String}         The generated sql query.
      */
     commitTransactionQuery: function(options) {
+      if (options.parent) {
+        return;
+      }
+
       return 'COMMIT;';
     },
 
@@ -1039,6 +1058,10 @@ module.exports = (function() {
      * @return {String}         The generated sql query.
      */
     rollbackTransactionQuery: function(options) {
+      if (options.parent) {
+        return 'ROLLBACK TO SAVEPOINT ' + this.quoteIdentifier(options.parent.id) + ';';
+      }
+
       return 'ROLLBACK;';
     },
 

lib/dialects/sqlite/query-generator.js

@@ -372,7 +372,11 @@ module.exports = (function() {
       });
     },
 
-    startTransactionQuery: function() {
+    startTransactionQuery: function(options) {
+      if (options.parent) {
+        return 'SAVEPOINT ' + this.quoteIdentifier(options.parent.id) + ';';
+      }
+
       return "BEGIN TRANSACTION;";
     },
 

lib/query-interface.js

@@ -699,13 +699,22 @@ module.exports = (function() {
     return this.sequelize.query(sql, null, { transaction: transaction});
   };
 
-  QueryInterface.prototype.setIsolationLevel = function(transaction, value) {
+  QueryInterface.prototype.setIsolationLevel = function(transaction, value, options) {
     if (!transaction || !(transaction instanceof Transaction)) {
       throw new Error('Unable to set isolation level for a transaction without transaction object!');
     }
 
-    var sql = this.QueryGenerator.setIsolationLevelQuery(value);
-    return this.sequelize.query(sql, null, { transaction: transaction });
+    options = Utils._.extend({
+      parent: options.transaction
+    }, options || {});
+
+    var sql = this.QueryGenerator.setIsolationLevelQuery(value, options);
+
+    if (sql) {
+      return this.sequelize.query(sql, null, { transaction: transaction });
+    } else {
+      return Utils.Promise.resolve();
+    }
   };
 
   QueryInterface.prototype.startTransaction = function(transaction, options) {
@@ -714,7 +723,8 @@ module.exports = (function() {
     }
 
     options = Utils._.extend({
-      transaction: transaction
+      transaction: transaction,
+      parent: options.transaction
     }, options || {});
 
     var sql = this.QueryGenerator.startTransactionQuery(options);
@@ -727,11 +737,17 @@ module.exports = (function() {
     }
 
     options = Utils._.extend({
-      transaction: transaction
+      transaction: transaction,
+      parent: options.transaction
     }, options || {});
 
     var sql = this.QueryGenerator.commitTransactionQuery(options);
-    return this.sequelize.query(sql, null, options);
+
+    if (sql) {
+      return this.sequelize.query(sql, null, options);
+    } else {
+      return Utils.Promise.resolve();
+    }
   };
 
   QueryInterface.prototype.rollbackTransaction = function(transaction, options) {
@@ -740,7 +756,8 @@ module.exports = (function() {
     }
 
     options = Utils._.extend({
-      transaction: transaction
+      transaction: transaction,
+      parent: options.transaction
     }, options || {});
 
     var sql = this.QueryGenerator.rollbackTransactionQuery(options);

lib/transaction.js

@@ -11,11 +11,11 @@ var Utils = require('./utils')
  */
 var Transaction = module.exports = function(sequelize, options) {
   this.sequelize = sequelize;
-  this.id = Utils.generateUUID();
   this.options = Utils._.extend({
     autocommit: true,
     isolationLevel: Transaction.ISOLATION_LEVELS.REPEATABLE_READ
   }, options || {});
+  this.id = this.options.transaction ? this.options.transaction.id : Utils.generateUUID();
 };
 
 /**
@@ -65,11 +65,17 @@ Transaction.LOCK = Transaction.prototype.LOCK = {
  * @return {this}
  */
 Transaction.prototype.commit = function() {
+  var self = this;
+
   return this
     .sequelize
     .getQueryInterface()
-    .commitTransaction(this, {})
-    .finally(this.cleanup.bind(this));
+    .commitTransaction(this, this.options)
+    .finally(function() {
+      if (!self.options.transaction) {
+        self.cleanup();
+      }
+    });
 };
 
 
@@ -79,19 +85,25 @@ Transaction.prototype.commit = function() {
  * @return {this}
  */
 Transaction.prototype.rollback = function() {
+  var self = this;
+
   return this
     .sequelize
     .getQueryInterface()
-    .rollbackTransaction(this, {})
-    .finally(this.cleanup.bind(this));
+    .rollbackTransaction(this, this.options)
+    .finally(function() {
+      if (!self.options.transaction) {
+        self.cleanup();
+      }
+    });
 };
 
 Transaction.prototype.prepareEnvironment = function() {
   var self = this;
 
-  return this.sequelize.connectionManager.getConnection({
-    uuid: self.id
-  }).then(function (connection) {
+  return Utils.Promise.resolve(
+    self.options.transaction ? self.options.transaction.connection : self.sequelize.connectionManager.getConnection({ uuid: self.id })
+  ).then(function (connection) {
     self.connection = connection;
     self.connection.uuid = self.id;
   }).then(function () {
@@ -102,11 +114,12 @@ Transaction.prototype.prepareEnvironment = function() {
     return self.setAutocommit();
   });
 };
+
 Transaction.prototype.begin = function() {
   return this
     .sequelize
     .getQueryInterface()
-    .startTransaction(this, {});
+    .startTransaction(this, this.options);
 };
 
 Transaction.prototype.setAutocommit = function() {
@@ -120,7 +133,7 @@ Transaction.prototype.setIsolationLevel = function() {
   return this
     .sequelize
     .getQueryInterface()
-    .setIsolationLevel(this, this.options.isolationLevel);
+    .setIsolationLevel(this, this.options.isolationLevel, this.options);
 };
 
 Transaction.prototype.cleanup = function() {

test/sequelize.test.js

@@ -888,6 +888,77 @@ describe(Support.getTestDialectTeaser("Sequelize"), function () {
         })
       }
 
+      it('supports nested transactions using savepoints', function(done) {
+        var self = this
+        var User = this.sequelize.define('Users', { username: DataTypes.STRING })
+
+        User.sync({ force: true }).success(function() {
+          self.sequelizeWithTransaction.transaction(function(t1) {
+            User.create({ username: 'foo' }, { transaction: t1 }).success(function(user) {
+              self.sequelizeWithTransaction.transaction({ transaction: t1 }, function(t2) {
+                user.updateAttributes({ username: 'bar' }, { transaction: t2 }).success(function() {
+                  t2.commit().then(function() {
+                    user.reload({ transaction: t1 }).success(function(newUser) {
+                      expect(newUser.username).to.equal('bar')
+
+                      t1.commit().then(function() {
+                        done()
+                      });
+                    })
+                  })
+                })
+              })
+            })
+          })
+        })
+      })
+
+      it('supports rolling back a nested transaction', function(done) {
+        var self = this
+        var User = this.sequelize.define('Users', { username: DataTypes.STRING })
+
+        User.sync({ force: true }).success(function() {
+          self.sequelizeWithTransaction.transaction(function(t1) {
+            User.create({ username: 'foo' }, { transaction: t1 }).success(function(user) {
+              self.sequelizeWithTransaction.transaction({ transaction: t1 }, function(t2) {
+                user.updateAttributes({ username: 'bar' }, { transaction: t2 }).success(function() {
+                  t2.rollback().then(function() {
+                    user.reload({ transaction: t2 }).success(function(newUser) {
+                      expect(newUser.username).to.equal('foo')
+
+                      t1.commit().then(function() {
+                        done()
+                      });
+                    })
+                  })
+                })
+              })
+            })
+          })
+        })
+      })
+
+      it('supports rolling back outermost transaction', function(done) {
+        var self = this
+        var User = this.sequelize.define('Users', { username: DataTypes.STRING })
+
+        User.sync({ force: true }).success(function() {
+          self.sequelizeWithTransaction.transaction(function(t1) {
+            User.create({ username: 'foo' }, { transaction: t1 }).success(function(user) {
+              self.sequelizeWithTransaction.transaction({ transaction: t1 }, function(t2) {
+                user.updateAttributes({ username: 'bar' }, { transaction: t2 }).success(function() {
+                  t1.rollback().then(function() {
+                    User.findAll().success(function(users) {
+                      expect(users.length).to.equal(0);
+                      done()
+                    })
+                  })
+                })
+              })
+            })
+          })
+        })
+      })
     })
   })
 })