I'm looking for the best way to find by id using the MongoDB Node driver.
I see that the _id field is an ObjectId, and so using a string for the id won't work. And I see that you could use ObjectId as follows:
var ObjectId = require('mongodb').ObjectId;
exports.show = function(req, res) {
var db = req.app.get('db');
var id = new ObjectId(req.params.id);
db.collection('posts').findOne({
_id: id
}, function(err, post) {
res.status(200).json(post);
});
};
But is there a best practice/more convenient way? I hadn't come across one in looking through the docs. Note: Mongoose has a findById method where you could just use the id string.
The _id field is already indexed, and findByID implicitly searches for one document, hence, findOne where you'll pass options {_id: id} as you're already doing.
As far as I understand, the major design consideration was to make native driver API similar to the mongo shell experience and keep it consistent all over the place (other drivers as well?). For this purpose you might want to keep API simple, yet powerful to cover all cases. So, to generalize, you have find() method and "a db.collection.findOne() method as a special case of find() that returns a single document."
Related
I am attempting a CRUD app with MEAN stack. I am using mongoose in Express to call to the MongoDB. I am using the FindOne function with a specified parameter, and it's always returning the same (incorrect) document.
I know I am connected to the correct database, since I get a document back from that collection, but it's always the same document, no matter what I pass as the parameter.
module.exports = mongoose.model('Player', playersSchema, 'players'); //in player.js
const Player = require('./model/players');
app.get('/api/player/:id', (req, res) =>{
Player.findOne({id: req.params.playerId},
function(err, player) {
if(err) {
res.json(err);
}
else {
res.json(player);
}
});
});
I have 3 separate "players", with three distinct "playerID" fields (38187361, 35167321, 95821442). I can use Postman to GET the following URL, for example:
http://localhost:3000/api/player/anythingyouWantInHere
and it will return 38187361, the first document. I've been over this website, many tutorials, and the Mongoose documentation and I can't see what I'm doing wrong..
I'd like to eventually find by playerId OR username OR email, but one hurdle at a time...
From the mongoose documentation of findOne, if you pass Id a null or an empty value, it will query db.players.findOne({}) internally which will return first document of the collection everytime you fetch. So make sure you are passing non-empty id here.
Note: conditions is optional, and if conditions is null or undefined,
mongoose will send an empty findOne command to MongoDB, which will
return an arbitrary document. If you're querying by _id, use
findById() instead.
Your route is '/api/player/:id', so the key on the req.params object will be 'id' not 'playerId'.
I don't know what/where/if you're populating the playerId param, but if you update your query to call req.params.id it should actually change the document based on the path as you seem to be wanting to do.
I had the same problem, and it was that the name of column's table was different from the model I had created.
In my model the name of the wrong column was "role" and in my table it was "rol".
I am trying to convert a string to ObjectId using
var body={};
var objId="57b40595866fdab90268321e";
body.id=mongoose.Types.ObjectId(objId);
myModel.collection.insert(body,function(err,data){
//causing err;
});
the above code is working fine when mongoose 4.4.16 is used, but if i update my mongoose to latest version(4.6.0) then problem occurs.
Err
object [
{
"_bsontype":"ObjectID",
"id:{"0":87,"1":180,"2":5,"3":235,"4":134,"5":111,"6":218,"7":185,"8":2,"9":104,"10":50,"11":111}
}
]
is not a valid ObjectId
The right way to insert new document is-
var newDocument = new myModel({
_id: mongoose.Types.ObjectId("57b40595866fdab90268321e")
});
newDocument.save();
In you case-
It stops working because the differences between versions of mongoose and mongo native drivers.
although, you are able to perform this by the example above, or, if you still want to use insert, you can use the myModel.insertMany (by passing object instead of array)
look here
http://mongoosejs.com/docs/api.html#model_Model.insertMany
I don't have the time to spike it, but if I remember correctly id is a simple string and _id is the ObjectId, i.e. either
body.id="57b40595866fdab90268321e"
or
body._id=mongoose.Types.ObjectId("57b40595866fdab90268321e");
That said, does it have to be that specific id? If not, you can use new myModel() and an id will be automatically created.
I am attempting to perform a relatively simple update using Mongoose:
var location = locationService.getLocation(typedLat, typedLong, travelRadius);
DocumentModel.update({_id : passedInId }, { location : location }, function(err, resp){
next(err, resp);
});
In this case passedInId is the string:
"561ee6bbe4b0f25b4aead5c8"
And in the object (test data I created) the id is:
"_id": ObjectId("561ee6bbe4b0f25b4aead5c8")
When I run the above however, matched documents is 0. I assume this is because passedInId is being treated like a string, however when I type it to an ObjectId:
var queryId = ObjectId(passedInId)
The result is the same, the document doesn't match. What am I missing? This seems like it should be obvious....
Mongoose will correctly interpret a string as an ObjectId. One of the following must be the case:
That record is not in the collection. Run a query in the mongo shell to check.
Mongoose I'd looking in collection other than the one containing your test data. Remember, by default, mongo will lowercase the name under which you register your model and will add an a "s" to it.
Lastly, and your answer speaks to this, maybe your model it's just not being updated with any new information.
This behavior was because I had not yet updated the model in mongoose to include the location element. There is no error, it just doesn't match or do anything.
I implementing module who automatically generate mongoose query by requested params, so for simplified test process I need to be able to get text representation of final query. How could I do that?
Like we have something like this:
var q = AppModel.find({id:777}).sort({date:-1})
I need to get something like this
"db.appmodels.where({id:777}).sort({date: -1})"
You can set debug for mongoose, which would by default send the queries to console, to use the following:
mongoose.set('debug', function (collectionName, method, query, doc) {
// Here query is what you are looking for.
// so whatever you want to do with the query
// would be done in here
})
Given a query object q you can rebuild the query using its fields, namely q._conditions and q._update. This is undocumented though and could easily break between versions of Mongoose (tested on Mongoose 4.0.4).
I'm trying to sort via mongoose 3.6.20 and I am receiving some unexpected results.
I have a list of companies with a name. At first I thought that maybe it was sorting in a case sensitive way. Which based on articles, I expect was true.
I'm now using a virtual property to down case the sort field. However, I'm still getting unexpected results.
CompanySchema.virtual('name_lower').get(function(){
return this.name.toLowerCase();
});
and when I sort
Company.find().sort({ name_lower: 1 });
I'm getting it in the following order:
company name
google
company name (yes a duplicate for testing)
I'm also outputting the value of my virtual property and it looks right. There is no whitespace or funky characters that would result in the 2nd 'company name' from appearing after google.
Using nodejs, express, mongoose.
What am I missing or doing incorrectly?
Update:
Based on the information provided in the answers, I refactored my schema to include some normalized fields and hooked into the pre save event of my document, where I update those normalized fields and sort using them in all future queries.
CompanySchema.pre('save', function(next){
this.normalized_name = this.name;
});
Next, is in the schema I use:
var CompanySchema = mongoose.Schema({
...
normalized_name: { type: String, set: normalize },
...
});
Where normalize is a function that for now, returns a lowercase version of the value passed into it. However, this allows me to expand on it later really fast, and I can quickly do the same to other fields that I might need to sort against.
As of MongoDB v3.4, case insensitive sorting can be done using collation method:
Company.find()
.collation({locale: "en" }) //or whatever collation you want
.sort({name:'asc'})
.exec(function(err, results) {
// use your case insensitive sorted results
});
Unfortunately MongoDB and Mongoose does not currently support complex sorting, so there are 2 options:
As you said, create a new field with the names sanitized to be all lowercase
Run a big for loop over all the data and update each company name to it's lower case form:
db.CompanyCollection.find().forEach(
function(e) {
e.CompanyName = e.CompanyName.toLowerCase();
db.CompanyCollection.save(e);
}
)
or
db.CompanyCollection.update({_id: e._id}, {$set: {CompanyName: e.CompanyName.toLowerCase()
Please see Update MongoDB collection using $toLower and Mongoose: Sort alphabetically as well for more info.
I want to put out that in this hook:
CompanySchema.pre('save', function(next){
this.normalized_name = this.name;
});
You'll have to call next(); at the end, if you want the normalized_name to be saved in the database, so the pre save hook would look like:
CompanySchema.pre('save', function(next){
this.normalized_name = this.name;
next();
});
This answer seems to be more helpful to me. I had to consider diacritics along with the case so I had used strength:3.
Mongoose: Sort alphabetically