如何用sails.js/waterline进行交易?
How to make transactions with sails.js/waterline?
我正在尝试将我的查询放入事务中,但我在运行时失败了。我得到的错误是:
Object #<bound> has no method 'transaction'
我试着关注 this "documentation".
简而言之,我的模型是这样的:
updateOrCreate: function (profile_id, positive,negative) {
var deferred = Q.defer();
Reputation.transaction().findOne().where({profile: profile_id}).then(function (rep) {
if (rep) {
// Reputation logic
rep.save(function (err) {deferred.resolve();});
} else {
// Reputation does not exist. Create.
Reputation.create({profile: profile_id, positive: positive,negative:negative}).exec(function (e, rep) {
deferred.resolve();});
}
}).fail(function (err) {deferred.reject()});
return deferred.promise;
}
有什么想法我做错了什么吗?
谢谢。
w.
您正在关注的 "documentation" 是关于如何 可以将事务支持添加 到 Sails 的提案。 Sails 中没有本机事务支持。有关如何使用 MySQL 或 Postgres 适配器的 .query
方法执行事务的示例,请参阅 this answer。
似乎 they don't support this。你可以使用类似的东西:
sails v1 现在支持此功能(2017 年 6 月 26 日尚未正式发布)。
您可以按照此 link 获取 next.sailsjs.com 中的文档:
Datastore.transaction()
在上面的文档中有以下示例:
sails.getDatastore()
.transaction(function (db, proceed) {
BankAccount.findOne({ owner: req.session.userId }).usingConnection(db)
.exec(function (err, myAccount) {
if (err) { return proceed(err); }
if (!myAccount) { return proceed(new Error('Consistency violation: Database is corrupted-- logged in user record has gone missing')); }
BankAccount.findOne({ owner: req.param('recipientId') }).usingConnection(db)
.exec(function (err, recipientAccount) {
if (err) { return proceed(err); }
if (!recipientAccount) {
err = new Error('There is no recipient with that id');
err.code = 'E_NO_SUCH_RECIPIENT';
return proceed(err);
}
// Do the math to subtract from the logged-in user's account balance,
// and add to the recipient's bank account balance.
var myNewBalance = myAccount.balance - req.param('amount');
// If this would put the logged-in user's account balance below zero,
// then abort. (The transaction will be rolled back automatically.)
if (myNewBalance < 0) {
err = new Error('Insufficient funds');
err.code = 'E_INSUFFICIENT_FUNDS';
return proceed(err);
}
// Update the current user's bank account
BankAccount.update({ owner: req.session.userId })
.set({
balance: myNewBalance
})
.usingConnection(db)
.exec(function (err) {
if (err) { return proceed(err); }
// Update the recipient's bank account
BankAccount.update({ owner: req.param('recipientId') })
.set({
balance: recipientAccount.balance + req.param('amount')
})
.usingConnection(db)
.exec(function (err) {
if (err) { return proceed(err); }
return proceed();
});
});
});
});
}).exec(function(err){
// At this point, we know that, if our code above passed through
// an error to `proceed`, Sails took care of rolling back the
// transaction. Otherwise, it committed it to the database.
if (err && err.code === 'E_INSUFFICIENT_FUNDS') {
return res.badRequest(err);
}
else if (err && err.code === 'E_NO_SUCH_RECIPIENT') {
return res.notFound();
}
else if (err) {
return res.serverError(err);
}
// All done!
return res.ok();
});
我正在尝试将我的查询放入事务中,但我在运行时失败了。我得到的错误是:
Object #<bound> has no method 'transaction'
我试着关注 this "documentation".
简而言之,我的模型是这样的:
updateOrCreate: function (profile_id, positive,negative) {
var deferred = Q.defer();
Reputation.transaction().findOne().where({profile: profile_id}).then(function (rep) {
if (rep) {
// Reputation logic
rep.save(function (err) {deferred.resolve();});
} else {
// Reputation does not exist. Create.
Reputation.create({profile: profile_id, positive: positive,negative:negative}).exec(function (e, rep) {
deferred.resolve();});
}
}).fail(function (err) {deferred.reject()});
return deferred.promise;
}
有什么想法我做错了什么吗?
谢谢。
w.
您正在关注的 "documentation" 是关于如何 可以将事务支持添加 到 Sails 的提案。 Sails 中没有本机事务支持。有关如何使用 MySQL 或 Postgres 适配器的 .query
方法执行事务的示例,请参阅 this answer。
似乎 they don't support this。你可以使用类似的东西:
sails v1 现在支持此功能(2017 年 6 月 26 日尚未正式发布)。 您可以按照此 link 获取 next.sailsjs.com 中的文档: Datastore.transaction()
在上面的文档中有以下示例:
sails.getDatastore()
.transaction(function (db, proceed) {
BankAccount.findOne({ owner: req.session.userId }).usingConnection(db)
.exec(function (err, myAccount) {
if (err) { return proceed(err); }
if (!myAccount) { return proceed(new Error('Consistency violation: Database is corrupted-- logged in user record has gone missing')); }
BankAccount.findOne({ owner: req.param('recipientId') }).usingConnection(db)
.exec(function (err, recipientAccount) {
if (err) { return proceed(err); }
if (!recipientAccount) {
err = new Error('There is no recipient with that id');
err.code = 'E_NO_SUCH_RECIPIENT';
return proceed(err);
}
// Do the math to subtract from the logged-in user's account balance,
// and add to the recipient's bank account balance.
var myNewBalance = myAccount.balance - req.param('amount');
// If this would put the logged-in user's account balance below zero,
// then abort. (The transaction will be rolled back automatically.)
if (myNewBalance < 0) {
err = new Error('Insufficient funds');
err.code = 'E_INSUFFICIENT_FUNDS';
return proceed(err);
}
// Update the current user's bank account
BankAccount.update({ owner: req.session.userId })
.set({
balance: myNewBalance
})
.usingConnection(db)
.exec(function (err) {
if (err) { return proceed(err); }
// Update the recipient's bank account
BankAccount.update({ owner: req.param('recipientId') })
.set({
balance: recipientAccount.balance + req.param('amount')
})
.usingConnection(db)
.exec(function (err) {
if (err) { return proceed(err); }
return proceed();
});
});
});
});
}).exec(function(err){
// At this point, we know that, if our code above passed through
// an error to `proceed`, Sails took care of rolling back the
// transaction. Otherwise, it committed it to the database.
if (err && err.code === 'E_INSUFFICIENT_FUNDS') {
return res.badRequest(err);
}
else if (err && err.code === 'E_NO_SUCH_RECIPIENT') {
return res.notFound();
}
else if (err) {
return res.serverError(err);
}
// All done!
return res.ok();
});