Monday, 8 February 2016

javascript - How do I update/upsert a document in Mongoose?



Perhaps it's the time, perhaps it's me drowning in sparse documentation and not being able to wrap my head around the concept of updating in Mongoose :)



Here's the deal:



I have a contact schema and model (shortened properties):



var mongoose = require('mongoose'),
Schema = mongoose.Schema;


var mongooseTypes = require("mongoose-types"),
useTimestamps = mongooseTypes.useTimestamps;


var ContactSchema = new Schema({
phone: {
type: String,
index: {
unique: true,

dropDups: true
}
},
status: {
type: String,
lowercase: true,
trim: true,
default: 'on'
}
});

ContactSchema.plugin(useTimestamps);
var Contact = mongoose.model('Contact', ContactSchema);


I receive a request from the client, containing the fields I need and use my model thusly:



mongoose.connect(connectionString);
var contact = new Contact({
phone: request.phone,
status: request.status

});


And now we reach the problem:




  1. If I call contact.save(function(err){...}) I'll receive an error if the contact with the same phone number already exists (as expected - unique)

  2. I can't call update() on contact, since that method does not exist on a document

  3. If I call update on the model:
    Contact.update({phone:request.phone}, contact, {upsert: true}, function(err{...})
    I get into an infinite loop of some sorts, since the Mongoose update implementation clearly doesn't want an object as the second parameter.

  4. If I do the same, but in the second parameter I pass an associative array of the request properties {status: request.status, phone: request.phone ...} it works - but then I have no reference to the specific contact and cannot find out its createdAt and updatedAt properties.




So the bottom line, after all I tried: given a document contact, how do I update it if it exists, or add it if it doesn't?



Thanks for your time.


Answer



Well, I waited long enough and no answer. Finally gave up the whole update/upsert approach and went with:



ContactSchema.findOne({phone: request.phone}, function(err, contact) {
if(!err) {

if(!contact) {
contact = new ContactSchema();
contact.phone = request.phone;
}
contact.status = request.status;
contact.save(function(err) {
if(!err) {
console.log("contact " + contact.phone + " created at " + contact.createdAt + " updated at " + contact.updatedAt);
}
else {

console.log("Error: could not save contact " + contact.phone);
}
});
}
});


Does it work? Yep. Am I happy with this? Probably not. 2 DB calls instead of one.
Hopefully a future Mongoose implementation would come up with a Model.upsert function.


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