I'm using a firebase database and a simple function with the new FieldValue.increment to increment a counter but that does not work but adds "operand" field without ever incrementing it.
My function is super simple:
exports.updateCounters = functions.https.onRequest((req, res) => {
// grab the parameters.
const username = req.query.username;
var updateObject = { };
updateObject[username] = admin.firestore.FieldValue.increment(1);
admin.database().ref('counterstest').update(updateObject);
});
When I deploy and call this function I would expect to see
countertest: {
myusername: 1
}
but I see
countertest: {
myusername: {
operand: 1
}
}
instead and operand: 1 never increments even if I call my function multiple times.
Can somebody point out what error I'm making here?
Thank you!
FieldValue.increment() is a feature of Cloud Firestore, but you're apparently trying to apply it to Realtime Database. This is not going to work - they are different databases, and Realtime Database doesn't support atomic increments like this.
What you're actually doing here is writing the JSON representation of the returned FieldValue object to Realime Database. Apparently, internally, the FieldValue object has a property called "operand" which contains the value to increment by.
I know this post is a couple of years old, but database.ServerValue.increment works with the 11.X firebase-admin Realtime Database like so:
admin.database().ref('counterstest').update({ myusername: database.ServerValue.increment(1) })
Related
I want to return an item with a specific ID and perform an update operation on it. My query gets the right result, but it won't let me update it.
I tried following this tutorial: https://www.youtube.com/watch?v=mYyPbfpoZeM
And read the documentation. Both didn't help. Other threads to the same topic are, well, different.
I have a database of objects which have a unique ID stored as integer.
I have an HTML form to get an ID as user input and the query below to retrieve the according object.
I tried this. The query worked, the update didn't.
db.collection('objects').where('ID','==', ID ).get().then((snapshot) => {
snapshot.docs.forEach( doc => {
console.log('debug');
console.log(doc.data().ID);
})
});
I am still new to firebase and js, so please forgive me if my code is uterly wrong.
I am currently stuck with this:
db.collection('objects').where('ID','==', ID ).get().then((doc) => {
console.table(doc);
});
Which is still not working.
For the second snippet an I currently get an unlegible table in which I can't really find the object I was looking for.
How do I update a single value in a single document?
EDIT: I forgot my implementation attempts of the update function.
I tried doc.update({value:0}) inside the for loop in snippet one which yielded doc.update is not a function. Similarly for doc.data().update(...).
In the second snippet I mainly tried to see what I got returned and ran variations of the above mentioned uodate function. With no success.
I managed to get it to work by studying the part of the firestore documentation that goes more into detail about the actual functions. Somehow it was hard for me to find this.
db.collection("users").where("name", "==", somename).limit(1).get().then(query => {
console.log(query);
const thing = query.docs[0];
console.log(thing.data());
let tmp = thing.data();
tmp.current_game_play = tmp.current_game_play + 1;
console.log(tmp);
thing.ref.update(tmp);
});
So I use where to get a Query object, use get to get a a querySnapshot inside the then promise resolve, use docs[0] to retrieve the first (and only) documentSnapshot and finally ref to get a reference that makes the whole thing updatable later.
try this:
var objectRef= db.collection("objects").doc(ID);
objectRef.update({
value: 0
}).then(function() {
console.log("Document successfully updated!");
}).catch(function(error) {
// The document probably doesn't exist.
console.error("Error updating document: ", error);
});
Problem
In a social media app I am making with react native and firebase, I am trying to grab the number of comments a post has using the snapshot function of a variable I have saved on my servers, then I am going to add one to this variable when a user adds a new comment. My code to do so is right here:
firebase.database().ref('posts').child(this.state.passKey).update({
comments: firebase.database().ref('posts/'+this.state.passKey).child('comments').snapshot.val() + 1
})
When I actually run this code, I get an error saying:
Reference.child failed: First argument was an invalid path = "undefined".
Paths must be non-empty strings and can't contain ".","#","$","[", or "["
At first I thought this might be that the "this.state.passKey" wasn't actually passing the key, but putting in a key I copied from the server didn't fix the problem.
My Server
-
To get the comments of particular post you should do like this
let postId='someId'
postRef=`/posts/${postId}`
firebase.database().ref(postRef).once("value", dataSnapshot => {
comment=dataSnapshot.val().comments
});
It looks like you're expecting this bit of code to query the database:
firebase.database().ref('posts/'+this.state.passKey).child('comments').snapshot.val() + 1
Unfortunately, it doesn't work that way. There's no snapshot property on a database Reference object returned by child() or ref().
Instead, you'll need to query the database at that reference, then when you're called back with its value, you can apply it elsewhere.
var ref = firebase.database().ref('posts/'+this.state.passKey+'/comments')
ref.once('value', function(snapshot) {
// use the snapshot here
})
I have to connect to the external database and get access to its collections. It works fine, when I use it, but the problem is when I need collection hooks, e.g. Collection.after.insert(function(userId, doc)). The hook is not being fired. I have following code:
// TestCollection.js
let database = new MongoInternals.RemoteCollectionDriver("mongodb://127.0.0.1:3001/meteor",
{
oplogUrl: 'mongodb://127.0.0.1:3001/local'
});
let TestCollection = new Mongo.Collection("testCollection", { _driver: database });
module.exports.TestCollection = TestCollection;
console.log(TestCollection.findOne({name: 'testItem'})); // writes out the item correctly
// FileUsingCollection.js
import { TestCollection } from '../collections/TestCollection.js';
console.log(TestCollection.findOne({name: 'testItem'})); // writes out the item correctly second time
TestCollection.after.update(function (userId, doc) {
console.log('after update');
}); // this is NOT being fired when I change the content of remote collection (in external app, which database I am connected)
How to make this work?
EDIT:
I have read many hours about it and I think it might be connected with things like:
- oplog
- replicaSet
But I am newbie to Meteor and can’t find out what are those things about. I have set MONGO_OPLOG_URL and I added oplog parameter to database driver as I read here: https://medium.com/#lionkeng/2-ways-to-share-data-between-2-different-meteor-apps-7b27f18b5de9
but nothing changed. And I don’t know how to use this replicaSet, how to add it to the url. Anybody can help?
You can also try something like below code,
var observer = YourCollections.find({}).observeChanges({
added: function (id, fields) {
}
});
You can also have 'addedBefore(id, fields, before)', 'changed(id, fields)', 'movedBefore(id, before)', 'removed(id)'
For more features goto link.
I'm looking to implement a solution where I can query the Mongoose Database on a regular interval and then store the results to serve to my clients.
I'm assuming this will reduce my response time when my users pull the collection.
I attempted to implement this plan by creating an empty global object and then writing a function that queries the db and then stores the results as the global object mentioned previously. At the end of the function I setTimeout for 60 seconds and then ran the function again. I call this function the first time the server controller gets called when the app is first run.
I then set my clients up so that when they requested the collection, it would first look to see if the global object exists, and if so return that as the response. I figured this would cut my 7-10 second queries down to < 1 sec.
In my novice thinking I assumed that Nodejs being 'single-threaded' something like this could work quite well - but it just seemed to eat up all my RAM and cause fatal errors.
Am I on the right track with my thinking or is it better to query the db every time people pull the collection?
Here is the code in question:
var allLeads = {};
var getAllLeads = function(){
allLeads = {};
console.log('Getting All Leads...');
Lead.find().sort('-lastCalled').exec(function(err, leads) {
if (err) {
console.log('Error getting leads');
} else {
allLeads = leads;
}
});
setTimeout(function(){
getAllLeads();
}, 60000);
};
getAllLeads();
Thanks in advance for your assistance.
I was searching for an easy and simple database for a little highscore system for a some games I'm developing in javascript.
I saw Orchestrate.io in github's student developer pack. I found a suitable drivermodule nodejs orchestrate and have integrated them.
The problem comes with querying orchestrate for my data. I have managed saving scores and querying them with db.list('collection'), but this seems to not responding with all data. It appered to me that some values are not returned.
I read about the db.search('collection','query') function. But I don't really understand how I could return all data because I don't want to query in a specific way.
My objects are as simple as follows:
{"name":"Jack","score":1337}
As I understand, one has to send a key, when putting such values to an orchestrate-collection. But I'd like to query the whole collection and get the values in a descendant order in regard to the score.
As for now I end up sorting the result on the client-side.
I hope you guys can give me some hints for a query that can sort for specific values!
You have the option to use a SearchBuilder
db.newSearchBuilder() //Build a search object
.collection('collection') //Set the collection to be searched
.sort(score, 'desc') //Set the order of the results
.query("*") //Empty search
.then(function (res) { //Callback function for results
//Do something with the results
})
Source
By default, .list uses a pagination limit of 10. You can either increase that, e.g.:
db.list('collection', { limit: 100 })
Or use .links, .links.next (from the docs):
db.list('collection', { limit: 10 })
.then(function (page1) {
// Got First Page
if (page1.links && page1.links.next) {
page1.links.next.get().then(function (page2) {
// Got Second Page
})
}
})