Error Handling mongoose with forEach loop
I have a mongodb with express and I'm getting Cannot set headers after they are sent to the client. Unhandled promise rejections are deprecated error when doing the following.
exports.deleteBooking = (req, res, next) => {
req.body.courts.forEach(element => {
Booking.deleteOne({$and: [
{ cid: element.cid },
{ year: element.day.year }
]})
.then(result => {
res.status(201).json({
message: result
});
})
.catch(() => {
res.status(500).json({
error: 'error'
})
});
})
};
I am sending an array of objects to my server and want to perform one deletion per object.
Because of the forEach it might run the .catch after the headers are sent to the client. What is the correct way of handling .then and .catch with a forEach loop?
Thank you!
EDIT: I forgot to add that if I would delete the .then and .catch the query would still run, and without errors. But I would like to keep the error handling in this case.
node.js mongodb mongodb-query
asked Nov 22 '18 at 14:27
DevchrisDevchris
102
add a comment |
I have a mongodb with express and I'm getting Cannot set headers after they are sent to the client. Unhandled promise rejections are deprecated error when doing the following.
exports.deleteBooking = (req, res, next) => {
req.body.courts.forEach(element => {
Booking.deleteOne({$and: [
{ cid: element.cid },
{ year: element.day.year }
]})
.then(result => {
res.status(201).json({
message: result
});
})
.catch(() => {
res.status(500).json({
error: 'error'
})
});
})
};
I am sending an array of objects to my server and want to perform one deletion per object.
Because of the forEach it might run the .catch after the headers are sent to the client. What is the correct way of handling .then and .catch with a forEach loop?
Thank you!
EDIT: I forgot to add that if I would delete the .then and .catch the query would still run, and without errors. But I would like to keep the error handling in this case.
node.js mongodb mongodb-query
asked Nov 22 '18 at 14:27
DevchrisDevchris
102
Should the response, whether it is error or message be send after the entire forEach loop is done or for each item in the loop?
– Jeevan
Nov 22 '18 at 14:57
So I tried this but then it gives the errorCannot read property 'then' of undefined
– Devchris
Nov 22 '18 at 15:17
add a comment |
I have a mongodb with express and I'm getting Cannot set headers after they are sent to the client. Unhandled promise rejections are deprecated error when doing the following.
exports.deleteBooking = (req, res, next) => {
req.body.courts.forEach(element => {
Booking.deleteOne({$and: [
{ cid: element.cid },
{ year: element.day.year }
]})
.then(result => {
res.status(201).json({
message: result
});
})
.catch(() => {
res.status(500).json({
error: 'error'
})
});
})
};
I am sending an array of objects to my server and want to perform one deletion per object.
Because of the forEach it might run the .catch after the headers are sent to the client. What is the correct way of handling .then and .catch with a forEach loop?
Thank you!
EDIT: I forgot to add that if I would delete the .then and .catch the query would still run, and without errors. But I would like to keep the error handling in this case.
node.js mongodb mongodb-query
asked Nov 22 '18 at 14:27
DevchrisDevchris
102
I have a mongodb with express and I'm getting Cannot set headers after they are sent to the client. Unhandled promise rejections are deprecated error when doing the following.
exports.deleteBooking = (req, res, next) => {
req.body.courts.forEach(element => {
Booking.deleteOne({$and: [
{ cid: element.cid },
{ year: element.day.year }
]})
.then(result => {
res.status(201).json({
message: result
});
})
.catch(() => {
res.status(500).json({
error: 'error'
})
});
})
};
I am sending an array of objects to my server and want to perform one deletion per object.
Because of the forEach it might run the .catch after the headers are sent to the client. What is the correct way of handling .then and .catch with a forEach loop?
Thank you!
EDIT: I forgot to add that if I would delete the .then and .catch the query would still run, and without errors. But I would like to keep the error handling in this case.
node.js mongodb mongodb-query
node.js mongodb mongodb-query
asked Nov 22 '18 at 14:27
DevchrisDevchris
102
asked Nov 22 '18 at 14:27
DevchrisDevchris
102
asked Nov 22 '18 at 14:27
DevchrisDevchris
102
asked Nov 22 '18 at 14:27
DevchrisDevchris
102
asked Nov 22 '18 at 14:27
DevchrisDevchris
102
102
Should the response, whether it is error or message be send after the entire forEach loop is done or for each item in the loop?
– Jeevan
Nov 22 '18 at 14:57
So I tried this but then it gives the errorCannot read property 'then' of undefined
– Devchris
Nov 22 '18 at 15:17
add a comment |
Should the response, whether it is error or message be send after the entire forEach loop is done or for each item in the loop?
– Jeevan
Nov 22 '18 at 14:57
So I tried this but then it gives the errorCannot read property 'then' of undefined
– Devchris
Nov 22 '18 at 15:17
Should the response, whether it is error or message be send after the entire forEach loop is done or for each item in the loop?
– Jeevan
Nov 22 '18 at 14:57
Should the response, whether it is error or message be send after the entire forEach loop is done or for each item in the loop?
– Jeevan
Nov 22 '18 at 14:57
So I tried this but then it gives the error
Cannot read property 'then' of undefined– Devchris
Nov 22 '18 at 15:17
So I tried this but then it gives the error
Cannot read property 'then' of undefined– Devchris
Nov 22 '18 at 15:17
add a comment |
2 Answers
2
active
oldest
votes
You can use the Promise.all instead of using forEach
exports.deleteBooking = (req, res, next) => {
const promises = req.body.courts.map(element =>
Booking.deleteOne({$and: [
{ cid: element.cid },
{ year: element.day.year }
]})
);
Promise.all(promises).then((results) => {
// Handle the result response
})
.catch((error) => {
// Handle the error response
})
};
answered Nov 22 '18 at 15:19
Med LazhariMed Lazhari
26215
Thanks a lot! This fixed the problem!
– Devchris
Nov 25 '18 at 18:55
add a comment |
res.status(201).json is within the forEach loop hence why you are getting the above error: you can only send data once.
To fix this, you basically need to send the deleteOne operations once and use bulkWrite() as it allows you to send multiple deleteOne operations to the MongoDB server in one command. It takes in input in form of an array of objects like the following
Booking.bulkWrite([
{ deleteOne: { filter: { cid: 1, year: 2007 } } },
{ deleteOne: { filter: { cid: 2, year: 2007 } } },
{ deleteOne: { filter: { cid: 3, year: 2007 } } },
{ deleteOne: { filter: { cid: 4, year: 2007 } } },
])
So in your case you can map req.body.courts array to the above deleteOne operations as
exports.deleteBooking = (req, res, next) => {
Booking.bulkWrite(
req.body.courts.map(({ cid, day }) => ({
deleteOne: { filter: { cid, year: day.year } }
}))
).then(message => {
res.status(201).json({ message })
}).catch(error => {
res.status(500).json({ error })
})
}
answered Nov 22 '18 at 15:33
chridamchridam
67k15109140
add a comment |
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2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
You can use the Promise.all instead of using forEach
exports.deleteBooking = (req, res, next) => {
const promises = req.body.courts.map(element =>
Booking.deleteOne({$and: [
{ cid: element.cid },
{ year: element.day.year }
]})
);
Promise.all(promises).then((results) => {
// Handle the result response
})
.catch((error) => {
// Handle the error response
})
};
answered Nov 22 '18 at 15:19
Med LazhariMed Lazhari
26215
Thanks a lot! This fixed the problem!
– Devchris
Nov 25 '18 at 18:55
add a comment |
You can use the Promise.all instead of using forEach
exports.deleteBooking = (req, res, next) => {
const promises = req.body.courts.map(element =>
Booking.deleteOne({$and: [
{ cid: element.cid },
{ year: element.day.year }
]})
);
Promise.all(promises).then((results) => {
// Handle the result response
})
.catch((error) => {
// Handle the error response
})
};
answered Nov 22 '18 at 15:19
Med LazhariMed Lazhari
26215
Thanks a lot! This fixed the problem!
– Devchris
Nov 25 '18 at 18:55
add a comment |
You can use the Promise.all instead of using forEach
exports.deleteBooking = (req, res, next) => {
const promises = req.body.courts.map(element =>
Booking.deleteOne({$and: [
{ cid: element.cid },
{ year: element.day.year }
]})
);
Promise.all(promises).then((results) => {
// Handle the result response
})
.catch((error) => {
// Handle the error response
})
};
answered Nov 22 '18 at 15:19
Med LazhariMed Lazhari
26215
You can use the Promise.all instead of using forEach
exports.deleteBooking = (req, res, next) => {
const promises = req.body.courts.map(element =>
Booking.deleteOne({$and: [
{ cid: element.cid },
{ year: element.day.year }
]})
);
Promise.all(promises).then((results) => {
// Handle the result response
})
.catch((error) => {
// Handle the error response
})
};
answered Nov 22 '18 at 15:19
Med LazhariMed Lazhari
26215
answered Nov 22 '18 at 15:19
Med LazhariMed Lazhari
26215
answered Nov 22 '18 at 15:19
Med LazhariMed Lazhari
26215
answered Nov 22 '18 at 15:19
Med LazhariMed Lazhari
26215
26215
Thanks a lot! This fixed the problem!
– Devchris
Nov 25 '18 at 18:55
add a comment |
Thanks a lot! This fixed the problem!
– Devchris
Nov 25 '18 at 18:55
Thanks a lot! This fixed the problem!
– Devchris
Nov 25 '18 at 18:55
Thanks a lot! This fixed the problem!
– Devchris
Nov 25 '18 at 18:55
add a comment |
res.status(201).json is within the forEach loop hence why you are getting the above error: you can only send data once.
To fix this, you basically need to send the deleteOne operations once and use bulkWrite() as it allows you to send multiple deleteOne operations to the MongoDB server in one command. It takes in input in form of an array of objects like the following
Booking.bulkWrite([
{ deleteOne: { filter: { cid: 1, year: 2007 } } },
{ deleteOne: { filter: { cid: 2, year: 2007 } } },
{ deleteOne: { filter: { cid: 3, year: 2007 } } },
{ deleteOne: { filter: { cid: 4, year: 2007 } } },
])
So in your case you can map req.body.courts array to the above deleteOne operations as
exports.deleteBooking = (req, res, next) => {
Booking.bulkWrite(
req.body.courts.map(({ cid, day }) => ({
deleteOne: { filter: { cid, year: day.year } }
}))
).then(message => {
res.status(201).json({ message })
}).catch(error => {
res.status(500).json({ error })
})
}
answered Nov 22 '18 at 15:33
chridamchridam
67k15109140
add a comment |
res.status(201).json is within the forEach loop hence why you are getting the above error: you can only send data once.
To fix this, you basically need to send the deleteOne operations once and use bulkWrite() as it allows you to send multiple deleteOne operations to the MongoDB server in one command. It takes in input in form of an array of objects like the following
Booking.bulkWrite([
{ deleteOne: { filter: { cid: 1, year: 2007 } } },
{ deleteOne: { filter: { cid: 2, year: 2007 } } },
{ deleteOne: { filter: { cid: 3, year: 2007 } } },
{ deleteOne: { filter: { cid: 4, year: 2007 } } },
])
So in your case you can map req.body.courts array to the above deleteOne operations as
exports.deleteBooking = (req, res, next) => {
Booking.bulkWrite(
req.body.courts.map(({ cid, day }) => ({
deleteOne: { filter: { cid, year: day.year } }
}))
).then(message => {
res.status(201).json({ message })
}).catch(error => {
res.status(500).json({ error })
})
}
answered Nov 22 '18 at 15:33
chridamchridam
67k15109140
add a comment |
res.status(201).json is within the forEach loop hence why you are getting the above error: you can only send data once.
To fix this, you basically need to send the deleteOne operations once and use bulkWrite() as it allows you to send multiple deleteOne operations to the MongoDB server in one command. It takes in input in form of an array of objects like the following
Booking.bulkWrite([
{ deleteOne: { filter: { cid: 1, year: 2007 } } },
{ deleteOne: { filter: { cid: 2, year: 2007 } } },
{ deleteOne: { filter: { cid: 3, year: 2007 } } },
{ deleteOne: { filter: { cid: 4, year: 2007 } } },
])
So in your case you can map req.body.courts array to the above deleteOne operations as
exports.deleteBooking = (req, res, next) => {
Booking.bulkWrite(
req.body.courts.map(({ cid, day }) => ({
deleteOne: { filter: { cid, year: day.year } }
}))
).then(message => {
res.status(201).json({ message })
}).catch(error => {
res.status(500).json({ error })
})
}
answered Nov 22 '18 at 15:33
chridamchridam
67k15109140
res.status(201).json is within the forEach loop hence why you are getting the above error: you can only send data once.
To fix this, you basically need to send the deleteOne operations once and use bulkWrite() as it allows you to send multiple deleteOne operations to the MongoDB server in one command. It takes in input in form of an array of objects like the following
Booking.bulkWrite([
{ deleteOne: { filter: { cid: 1, year: 2007 } } },
{ deleteOne: { filter: { cid: 2, year: 2007 } } },
{ deleteOne: { filter: { cid: 3, year: 2007 } } },
{ deleteOne: { filter: { cid: 4, year: 2007 } } },
])
So in your case you can map req.body.courts array to the above deleteOne operations as
exports.deleteBooking = (req, res, next) => {
Booking.bulkWrite(
req.body.courts.map(({ cid, day }) => ({
deleteOne: { filter: { cid, year: day.year } }
}))
).then(message => {
res.status(201).json({ message })
}).catch(error => {
res.status(500).json({ error })
})
}
answered Nov 22 '18 at 15:33
chridamchridam
67k15109140
answered Nov 22 '18 at 15:33
chridamchridam
67k15109140
answered Nov 22 '18 at 15:33
chridamchridam
67k15109140
answered Nov 22 '18 at 15:33
chridamchridam
67k15109140
67k15109140
add a comment |
add a comment |
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Should the response, whether it is error or message be send after the entire forEach loop is done or for each item in the loop?
– Jeevan
Nov 22 '18 at 14:57
So I tried this but then it gives the error
Cannot read property 'then' of undefined– Devchris
Nov 22 '18 at 15:17