mongoose transaction not working as expected - mongodb

Question

I have this code where I create a mongoose transaction. However it's not working as I expect. As you can see here, I'm testing the transaction by throwing an error before it can complete. However, for some reason, the account is always persisted rather than rolling back the transaction. Why
export const signUp = catchAsync(async (req: Request, res: Response, next: NextFunction) => {
const createdAt = req.body.createdAt ? new Date(req.body.createdAt) : new Date()
const session = await mongoose.startSession()
try {
session.startTransaction()
const account: IAccount = await Account.create<ICreateAccountInput>(
[
{
createdAt,
accountName: req.body.accountName,
accountOwnerName: req.body.accountOwnerName,
accountOwnerEmail: req.body?.accountOwnerEmail,
contactName: req.body?.contactName || undefined,
contactNumber: req.body.contactNumber || undefined,
contactEmail: req.body.contactEmail || undefined,
},
],
{ session },
)[0]
// throw error to test transaction cancellation
throw new Error('Test error')
const accountAdmin: IUser = await User.create<ICreateUserInput>(
[
{
createdAt,
accountId: account._id,
username: req.body.accountOwnerName,
email: req.body.accountOwnerEmail,
role: UserRoles.AccountAdmin,
password: req.body.password,
passwordConfirm: req.body.passwordConfirm,
},
],
{ session },
)[0]
await session.commitTransaction()
createSendToken(accountAdmin, 201, res, account)
} catch (e) {
session.abortTransaction()
throw e
} finally {
session.endSession()
}
})
Here is my catchAsync function in case this is the issue. It just catches errors so I don't have to write try/catch blocks everywhere:
export const catchAsync = fn => {
return (req, res, next) => {
fn(req, res, next).catch(next)
}
}

Answer 1

That code creates a session and transaction, but the account create is not using that session, so it is not within the transaction.
To correct this, wrap the object passed to create in an array and add the session option to the call:
Account.create<ICreateAccountInput>([{
createdAt,
accountName: req.body.accountName,
accountOwnerName: req.body.accountOwnerName,
accountOwnerEmail: req.body?.accountOwnerEmail,
contactName: req.body?.contactName || undefined,
contactNumber: req.body.contactNumber || undefined,
contactEmail: req.body.contactEmail || undefined,
}],
{session: session}
)