The mongoose query is fetching the correct results but i am unable to access the data.
I want to get the current max id in the database, increment the value by 1 and save the data to the database
// add a new book
router.route('/books/add').post(jsonParser, (req, res) => {
Book.aggregate([{ $group: { _id: "id", id: { $max: "$id" } } }], (err, books) => {
if (!books)
return next(new Error("Could not load book!"))
else {
let book = new Book(req.body);
// log the max id returned, currently returns undefined
console.log("Id found ", books.id);
book.id = books.id + 1;
console.log("BookId ", book.id);
res.status(200).json({ 'book': 'Added successfully!' });
// book.save().then(book => {
// res.status(200).json({ 'book': 'Added successfully!' });
// }).catch(err => {
// res.status(400).send('Failed to create new record.');
// });
}
});
});
console.log(books.id) returns undefined whereas console.log(books) does show me the result which is [ { _id: 'id', id: 5 } ]. What i want to do is get the id i.e. 5, how do i do that ? Thank you.
The aggregate query result is an array,, and you have to use the zero index to get the first element which is an object contains your result. Try this:
console.log(books[0].id)
Related
I am trying to update two rows in my players table based on the id. I am trying to use the updateMany method where id can be found in an array of id's but I am getting the {"message":"Invalid update pipeline operator: \"_id\""} error. I checked the array to make sure it is valid id's. Here is my code
const winningTeam = asyncHandler(async (req, res) => {
req.body.forEach((element) => {
element.wins += 1;
element.lastPlayed = Date.now();
element.percentage = (element.wins / (element.wins + element.wins)) * 1000;
});
let usersId = [];
usersId.push(req.body[0]._id);
if (req.body.length === 2) {
usersId.push(req.body[1]._id);
}
const player = await Player.updateMany({ _id: { $in: usersId } }, req.body);
if (player) {
res.status(200).json(player);
} else {
res.status(400);
throw new Error("Invalid Data");
}
});
You should use $set property for the update parameter. I'm not sure about the structure of your req.body but it should be something like this:
Player.updateMany({ _id: { $in: usersId } }, {$set: req.body});
instead of this:
Player.updateMany({ _id: { $in: usersId } }, req.body);
Take a look at docs for updateMany
I'm fairly new to nodejs and I'm doing a full stack developer challenge from devchallenges.io (Shoppingify). Below, I'm trying to increase the quantity value based on whether the user clicks to increase or decrease the item quantity. However, there's a slight delay between the return value from the request and the actual value in the database. It seems that the value updates immediately which is great however, the return value in the request is the previous value rather than being the current quantity value in the database.
mongoDB Database
// #route PUT api/list/item/quantity/:id
// #desc update item quantity
// #access Private
router.put('/item/quantity/:id', auth, async (req, res) => {
const { action } = req.body;
try {
let list = await List.findOne({ user: req.user.id });
// find current quantity
const item = list.items.find((item) => {
return item._id.toString() === req.params.id;
});
// increase quantity
if (action === 'increase') {
list = await List.findOneAndUpdate(
{ 'items._id': req.params.id },
{ $set: { 'items.$.quantity': item.quantity + 1 } },
{ new: true }
);
} else {
// decrease quantity
list = await List.findOneAndUpdate(
{ 'items._id': req.params.id },
{ $set: { 'items.$.quantity': item.quantity - 1 } },
{ new: true }
);
}
res.json(item.quantity);
} catch (error) {
console.error(error.message);
res.status(500).send('Server Error');
}
});
You are defining item in here:
const item = list.items.find((item) => {
return item._id.toString() === req.params.id;
});
At this point list is the "old" version of the object, you want to be doing the same after the update when the list object is updated and only then to return it.
// this is the original "list" item
let item = list.items.find((item) => {
return item._id.toString() === req.params.id;
});
...
update list
...
// now "list" is updated
item = list.items.find((item) => {
return item._id.toString() === req.params.id;
});
I will just add two additional tips to improve performance, they are mutually exclusive so you'll have to choose one of the two.
in the update query add the list._id to it, If I were to guess the collection does not have an index on the items field ( and if it does it's a bad idea usually ). this means when you updated just using the item._id field it takes longer for mongo to find the object. it's quick change to both updates:
list = await List.findOneAndUpdate(
{ _id: list._id, 'items._id': req.params.id },
{ $set: { 'items.$.quantity': item.quantity - 1 } },
{ new: true }
);
(my preferred option) do it in a single call, using the update arrayFilters option, like so:
const list = await List.findOneAndUpdate(
{
user: req.user.id,
},
{
$inc: {
'items.$[elem].quantity': action === 'increase' ? 1 : -1,
},
},
{
arrayFilters: [
{
'elem._id': new ObjectId(req.params.id),
},
],
new: true,
});
const item = list.items.find((item) => {
return item._id.toString() === req.params.id;
});
Mongo Playground
In my opinion now your route looks much better, you're also cutting down from 2 db calls to 1.
I am creating a call that deletes all the users except the current user logged in.
Here is my code;
exports.deletealluser = async (req, res) => {
try {
const { sub } = req.user;
const usersExceptCurrent = await User.find({ _id: !sub });
const deletedUsers = await User.deleteMany(usersExceptCurrent);
res.status(201).json({
message: 'A all user is successfully deleted!',
deletedUsers,
});
} catch (err) {
return res.status(400).json({
message: 'Something went wrong.',
});
}
};
sub is the id of the current user. As you can see, I call find query first to filter the data which is not equal to sub. Then I use the usersExceptCurrent as filter to my deleteMany query.
But it returns status 400
And here is my axios call;
const onDelete = async () => {
try {
const { data } = await fetchContext.authAxios.delete(
'admin/delete-all-users'
);
fetchContext.setUserList(
fetchContext.userList.filter((row) => row === data.deletedUsers)
);
setSignupSuccess(data.message);
setSignupError('');
setOpen(false);
setOpenAlert(false);
} catch (err) {
setIsLoaded(true);
setError(err);
const { data } = err.response;
setSignupError(data.message);
setSignupSuccess('');
}
};
Use $ne
$ne selects the documents where the value of the field is not equal to the specified value. This includes documents that do not contain the field.
db.collection.find({ _id: { $ne: sub } })
Demo - https://mongoplayground.net/p/ecMNn4ueZrn
If you still face for _id should be ObjectId you can do
const ObjectId = require("mongodb").ObjectId;
db.collection.find({ _id: { $ne: ObjectId(sub) } })
See what ! does, converts to bool value in JS
console.log(!"a");
console.log(!2);
I have the following express route:
const updateSnapshot = async (req, res) => {
const accountId = req.body.account_id;
if (!accountId) {
return fail(res, 'account id is missing', 400);
}
try {
const account = await Account
.findOne({ _id: accountId})
.populate({
path: 'snapshot',
model: 'Snapshot'
});
// I want to update these fields in snapshot
const snapshot = {
friends_count: data.friends_count,
updated_date: new Date()
};
account.snapshot.friends_count = snapshot.friends_count;
account.snapshot.updated_date = snapshot.updated_date;
await account.save();
return success(res, snapshot);
} catch(error) {
fail(res, error.message, 500);
}
};
I want to update the nested object snapshot (just the fields friends_count and update_date) however when I check the database it seems to have not work. What am I doing wrong here?
const updateSnapshot = (req, res) => {
const accountId = req.body.account_id;
if (!accountId) {
return fail(res, 'account id is missing', 400);
};
Account
.findOneAndUpdate({ _id: accountId }, {
$set: {
snapshot: {
friends_count: data.friends_count,
updated_date: new Date()
}
}
}, {
new: true
})
.then(account => {
if(!account) {
return fail(res, "Account not found", 404);
} else {
return success(res, account);
};
})
.catch(err => {
return fail(res, error.message, 500);
});
};
Here we're using the findOneAndUpdate method and promises to find and update the document in one operation.
findOneAndUpdate takes the query criteria as the first parameter, the second parameter updates values specified in the object (we're using the $set operator to update specific values of the snapshot object), and the three parameter is an object that defines the operation's options (new is set to true to return the newly updated object).
Note: $set will replace the entire snapshot object so if there are other properties inside the snapshot object, they will need to be included inside the $set object.
I'm having trouble returning a specific piece of data in my MEAN app. I'm trying to return only a specific part of my mongoose schema(Invoice).. I'm currently fetching the specific invoice by it's ID, then I'm trying to check if the invoice contains an "invoiceType" inside a nested array that equals a specific parameter.
I've tried using find({'_id': userId}, {'services.serviceType': 'one'}), but that returns both service types, regardless of being serviceType one or two.
// This is my array.. I'm trying to return the serviceType and serviceDescription if serviceType is equal to 'one'
{
'id': number,
'fistName': string,
'services': [
'serviceType': string
'serviceDescription': string
]
}
// here is my express code where i'm trying to make the call
Invoice.find({'_id': invoice_id},{'services.serviceType': 'one'})
.then(invoice => {
res.json(invoice)
});
You need to use $elemMatch so search inner array like this:
Invoice.findOne({ '_id': invoice_id }, { 'services': { $elemMatch: { "serviceType": "one" } } })
.then(invoice => {
res.json(invoice)
})
.catch(err => {
console.log(err);
return res.status(500).send("someting went wrong");
});
And if you want to filter other serviceTypes from the response, you can filter them like this:
Invoice.findOne({ '_id': invoice_id }, { 'services': { $elemMatch: { serviceType: "one" } } })
.then(invoice => {
if (!invoice) {
return res.status(404).send("Not found");
}
let filteredServiceTypes = res.services.filter(s => s.serviceType === "one");
invoice.services = filteredServiceTypes;
return res.json(invoice);
}).catch(err => {
console.log(err);
return res.status(500).send("someting went wrong");
});