Meteor Subscriptions Selecting the Entire Set? - mongodb

I've defined a publication:
Meteor.publish('uninvited', function (courseId: string) {
return Users.find({
'profile.courses': {
$ne: courseId
}
});
});
So, in when a subscriber subscribes to this, I expect Users.find() to return only users that are not enrolled in that particular course. So, on my client, when I write:
this.uninvitedSub = MeteorObservable.subscribe("uninvited", this.courseId).subscribe(() => {
this.uninvited = Users.find().zone()});
I expect uninvited to contain only a subset of users, however, I'm getting the entire set of users regardless of whether or not they are enrolled in a particular course. I've made sure that my data is correct and that there are users enrolled in the course that I'm concerned with. I've also verified that this.courseId is working as expected. Is there an error with my code, or should I further look into my data to see if there's anything wrong with it?
**Note:
When I write this:
this.uninvitedSub = MeteorObservable.subscribe("uninvited", this.courseId).subscribe(() => {
this.uninvited = Users.find({
'profile.courses': {}
}).zone();
});
With this, it works as expected! Why? The difference is that my query now contains 'profile.courses': {}.

Related

Mongodb Ref dynamic populate with grapqhl?

I have to decide whether to populate or not according to the query request, but I don't know how to do it.
So Example
If my model User is looks like this
below syntax is from typegoose and typegraphql
class User {
#Field()
#prop()
name: string;
#Field()
#prop(ref:"House")
house: Ref<House>
}
And here is two diffent query
Query1
user {
name
}
Query2
user {
name
house {
location
}
}
And in the resolver
User: () => {
const user = UserModel.find(blahblah)**.populate("house")**
return user
}
Query1 dose not need populate
but Query2 need
in same resolver!
I want to decide whether to populate or not depending on the requirements of the query.
I can't decide whether to populate or not without knowing what is the actual query was in resolver.
I found very similar question in stackoverflow
But there is not proper answer...
Solving relationships in Mongoose and GraphQL
i dont know much about graphql, but i think there is some method to get if that path is requested, so the following should work:
let query = Model.find(basicQuery);
if (req.path) { // replace this with graphql's method to get if the path is requested
query = query.populate(yourPath);
}
const doc = await query.exec();
PS: but as an comment already noted, i think there is some better method to do this in graphql (another resolver?)

elemMatch for fields in different levels

I'm asking this question after trying solve this problem all day long.
I want to get my users address by userId and by addressId. Since I receive data from post requests, I need to ensure that the query contains both userId and addressId in order to avoid security problems. The result of the query below returns all addresses from my user, instead of just the address containing the correct addressId.
async getUserAddress(_id: string, addressId: string) {
const user = await this.userModel.findOne(
{
_id,
addresses: {
$elemMatch: {
addressId: Types.ObjectId(addressId)
}
}
}
)
if (!user) {
throw new NotFoundException();
}
return user.addresses[0];
}
Since is impossible to use $elemMatch in different document levels, or even at the top level of the query, I find no better way to make this query without using filters. Are there any insights?
Tks in advance

Mutation cache update not working with vue-apollo and Hasura

I'm completely new to these technologies, and am having trouble wrapping my head around it, so bear with me. So, my situation is that I've deployed Hasura on Heroku and have added some data, and am now trying to implement some functionality where I can add and edit certain rows of a table. Specifically I've been following this from Hasura, and this from vue-apollo.
I've implemented the adding and editing (which works), and now want to also reflect this in the table, by using the update property of the mutation and updating the cache. Unfortunately, this is where I get lost. I'll paste some of my code below to make my problem more clear:
The mutation for adding a player (ADD_PLAYER_MUTATION) (same as the one in Hasura's documentation linked above):
mutation addPlayer($objects: [players_insert_input!]!) {
insert_players(objects: $objects) {
returning {
id
name
}
}
}
The code for the mutation in the .vue file
addPlayer(player, currentTimestamp) {
this.$apollo.mutate({
mutation: PLAYER_ADD_MUTATION,
variables: {
objects: [
{
name: player.name,
team_id: player.team.id,
created_at: currentTimestamp,
updated_at: currentTimestamp,
role_id: player.role.id,
first_name: player.first_name,
last_name: player.last_name
}
]
},
update: (store, { data: { addPlayer } }) => {
const data = store.readQuery({
query: PLAYERS
});
console.log(data);
console.log(addPlayer);
data.players.push(addPlayer);
store.writeQuery({ query: PLAYERS, data });
}
});
},
I don't really get the update part of the mutation. In most examples the { data: { x } } bit uses the function's name in the place of x, and so I did that as well, even though I don't really get why (it's pretty confusing to me at least). When logging data the array of players is logged, but when logging addPlayer undefined is logged.
I'm probably doing something wrong that is very simple for others, but I'm obviously not sure what. Maybe the mutation isn't returning the correct thing (although I'd assume it wouldn't log undefined in that case), or maybe isn't returning anything at all. It's especially confusing since the player is actually added to the database, so it's just the update part that isn't working - plus, most of the guides / tutorials show the same thing without really much explanation.
Okay, so for anyone as stupid as me, here's basically what I was doing wrong:
Instead of addPlayer in update: (store, { data: { addPlayer } }), it should be whatever the name of the mutation is, so in this case insert_players.
By default a mutation response from Hasura has a returning field, which is a list, and so the added player is the first element in the list, so you can get it like so: const addedPlayer = insert_players.returning[0];
I didn't want to just delete my question after realising what was wrong shortly after posting it, in case this is useful to other people like me, and so I'll leave it up.

Query sailsjs blueprint endpoints by id array using request

I'm using the request library to make calls from one sails app to another one which exposes the default blueprint endpoints. It works fine when I query by non-id fields, but I need to run some queries by passing id arrays. The problem is that the moment you provide an id, only the first id is considered, effectively not allowing this kind of query.
Is there a way to get around this? I could switch over to another attribute if all else fails but I need to know if there is a proper way around this.
Here's how I'm querying:
var idArr = [];//array of ids
var queryParams = { id: idArr };
var options: {
//headers, method and url here
json: queryParams
};
request(options, function(err, response, body){
if (err) return next(err);
return next(null, body);
});
Thanks in advance.
Sails blueprint APIs allow you to use the same waterline query langauge that you would otherwise use in code.
You can directly pass the array of id's in the get call to receive the objects as follows
GET /city?where={"id":[1, 2]}
Refer here for more.
Have fun!
Alright, I switched to a hacky solution to get moving.
For all models that needed querying by id arrays, I added a secondary attribute to the model. Let's call it code. Then, in afterCreate(), I updated code and set it equal to the id. This incurs an additional database call, but it's fine since it's called just once - when the object is created.
Here's the code.
module.exports = {
attributes: {
code: {
type: 'string'//the secondary attribute
},
// other attributes
},
afterCreate: function (newObj, next) {
Model.update({ id: newObj.id }, { code: newObj.id }, next);
}
}
Note that newObj isn't a Model object as even I was led to believe. So we cannot simply update its code and call newObj.save().
After this, in the queries having id arrays, substituting id with code makes them work as expected!

Mongoose - update after populate (Cast Exception)

I am not able to update my mongoose schema because of a CastERror, which makes sence, but I dont know how to solve it.
Trip Schema:
var TripSchema = new Schema({
name: String,
_users: [{type: Schema.Types.ObjectId, ref: 'User'}]
});
User Schema:
var UserSchema = new Schema({
name: String,
email: String,
});
in my html page i render a trip with the possibility to add new users to this trip, I retrieve the data by calling the findById method on the Schema:
exports.readById = function (request, result) {
Trip.findById(request.params.tripId).populate('_users').exec(function (error, trip) {
if (error) {
console.log('error getting trips');
} else {
console.log('found single trip: ' + trip);
result.json(trip);
}
})
};
this works find. In my ui i can add new users to the trip, here is the code:
var user = new UserService();
user.email = $scope.newMail;
user.$save(function(response){
trip._users.push(user._id);
trip.$update(function (response) {
console.log('OK - user ' + user.email + ' was linked to trip ' + trip.name);
// call for the updated document in database
this.readOne();
})
};
The Problem is that when I update my Schema the existing users in trip are populated, means stored as objects not id on the trip, the new user is stored as ObjectId in trip.
How can I make sure the populated users go back to ObjectId before I update? otherwise the update will fail with a CastError.
see here for error
I've been searching around for a graceful way to handle this without finding a satisfactory solution, or at least one I feel confident is what the mongoosejs folks had in mind when using populate. Nonetheless, here's the route I took:
First, I tried to separate adding to the list from saving. So in your example, move trip._users.push(user._id); out of the $save function. I put actions like this on the client side of things, since I want the UI to show the changes before I persist them.
Second, when adding the user, I kept working with the populated model -- that is, I don't push(user._id) but instead add the full user: push(user). This keeps the _users list consistent, since the ids of other users have already been replaced with their corresponding objects during population.
So now you should be working with a consistent list of populated users. In the server code, just before calling $update, I replace trip._users with a list of ObjectIds. In other words, "un-populate" _users:
user_ids = []
for (var i in trip._users){
/* it might be a good idea to do more validation here if you like, to make
* sure you don't have any naked userIds in this array already, as you would
*/in your original code.
user_ids.push(trip._users[i]._id);
}
trip._users = user_ids;
trip.$update(....
As I read through your example code again, it looks like the user you are adding to the trip might be a new user? I'm not sure if that's just a relic of your simplification for question purposes, but if not, you'll need to save the user first so mongo can assign an ObjectId before you can save the trip.
I have written an function which accepts an array, and in callback returns with an array of ObjectId. To do it asynchronously in NodeJS, I am using async.js. The function is like:
let converter = function(array, callback) {
let idArray;
async.each(array, function(item, itemCallback) {
idArray.push(item._id);
itemCallback();
}, function(err) {
callback(idArray);
})
};
This works totally fine with me, and I hope should work with you as well