I am using Getx state management for my project and trying to fetch data from backend but it does not store in my list .after checking in debugger mode ,I found out this error after it goes to (.tolist).function is following ?.
var productlist = <Productmodel>[].obs;
Productmodel.frommap( DocumentSnapshot snapshot) {
id = snapshot['id'];
productname = snapshot['name'];
price = snapshot['price'];
image = snapshot['image'];
brand = snapshot['brand'];
}
Stream<List<Productmodel>> _readdata() {
return firebasefirestore.collection('product').snapshots().map((query) =>
query.docs
.map((productmodel)
=> Productmodel.frommap(productmodel))
.toList());
}
error is the one I marked with green line
Related
Just started using the Realm MongoDB and i watched this video https://www.youtube.com/watch?v=Evp3xTzWCu4 from MongoDB and followed exactly what he did, but for some the function on the client side is not working. I'm using Expo React Native
I have this simple Realm function
exports = function(arg){
var collection = context.services.get("mongodb-atlas").db("questiondb").collection("questions");
collection.insertOne({name:arg}).then((doc) => {
console.log('Success')
}).catch(error=>console.log(error))
};
When i call it in the real console, it works fine.
This is the front end function
const connectDB = async () => {
const appID = "myapp-ckwfl";
const app = new Realm.App({ id: appID });
const credentials = Realm.Credentials.anonymous();
try {
const user = await app.logIn(credentials);
await user.functions.addQuestion("Myself");
console.log("Logged in");
} catch (error) {
console.log(error);
}
};
I'm getting the 'Logged in' in the console.
I went to check the activity log on the MongoDB atlas and it shows OK to both login and function
However, the function log shows me this message
[ "FunctionError: can't find a table mapping for namespace questiondb.questions" ] { "name": "addQuestion" }
And i have the database 'questiondb' with the collection 'questions'.
What am i missing here?
I ran into a similar error. The problem was that my BSON did not contain an "_id" field. But the BSON validation when saving it allowed me to save the schema like that. But when querying data through graphql I got this exact same error. So the solution was to fix the BSON schema. Even if the BSON schema saves and deploys successfully it can still be that it will not work for graphql.
You can see if your BSON has errors by navigating here:
I am building an app using Firebase Firestore as a BaaS.
But I am facing a problem when I try to create a feed/implement full-text-search on my app.
I want to be able to search through all the users posts, the problem is, the users posts are structured like this in the Firestore Database:
Posts(collection) -> UserID(Document) -> user posts(subcollection that holds all userID posts) -> actual posts(separate documents within that collection)
I want to loop through every user's user posts subcollection and fetch all data for the feed, and also to implement it with a full text search app like Algolia or ES.
I can loop through a specific user ID(code below), but being a beginner, I couldn't find a way to loop through all of them and fetch all of them.
firebase.firestore()
.collection('allPosts')
.doc('SPECIFIC_USER_ID') //-> Here I have to loop through all docs in that collection
.collection('userPosts')
.orderBy("creation", "asc")
.get()
.then((snapshot) => {
let posts = snapshot.docs.map(doc => {
const data = doc.data();
const id = doc.id;
return { id, ...data }
})
setUserPosts(posts)
})
}
Would love some help!
Collection Group Query
You can query in all collections named X using a collection group query.
var posts= db.collectionGroup('userPosts').orderBy('creation').limit(10);
posts.get().then((querySnapshot) => {
let posts = querySnapshot.map(doc => {
const data = doc.data();
const id = doc.id;
return { id, ...data }
})
setUserPosts(posts)
});
Source: https://firebase.google.com/docs/firestore/query-data/queries#collection-group-query
Algolia implementation
You will need to use Cloud Functions to migrate fields to a dedicated collection specifically for Algolia. Many users have found nested SubCollections to be problematic with Algolia's setup.
You do this by duplicating the user Post data as a 'source' to this new public collection, and using the Firebase Algolia Extension, you can sync it directly
exports.bakePosts= functions.firestore
.document('allPosts/{userID}/userPosts/{postID}')
.onWrite((change, context) => {
// Get an object with the current document value.
// If the document does not exist, it has been deleted.
const document = change.after.exists ? change.after.data() : null;
// Get an object with the previous document value (for update or delete)
const oldDocument = change.before.data();
if(document != null)
db.collection("posts/"+ context.params.postID).set(document);
if(document == null)
db.collection("posts/"+ context.params.postID).delete();
});
Algolia Extension:
https://firebase.google.com/products/extensions/firestore-algolia-search
You can avoid most of the above if you simply submit posts to a master collection and have the userID as the 'owner' property within the document. The above also have benefits, but more related to blog posts where users may have a "work in progress" version vs Live.
The Algolia Extension has the full guide on how to set it up and if you need to customize the extensions, the source code is also available.
I've been trying to save data from my form in my MongoDB for some time.
I also get a response from the database.
See also: create object in mongo db api onclick sending form
Unfortunately there are not enough tutorials in my mother tongue and I don't seem to understand everything in English.
I've tried some of the documentation, but I always fail.
What is missing in my webhook function so that the form data can be stored?
exports = function(payload) {
const mongodb = context.services.get("mongodb-atlas");
const mycollection = mongodb.db("created_notifications").collection("dpvn_collection");
return mycollection.find({}).limit(10).toArray();
};
The Webhookfunction was totally wrong.
READ THE DOCUMENTATION FIRST
exports = function(payload, response) {
const mongodb = context.services.get("mongodb-atlas");
const requestLogs = mongodb.db("created_notifications").collection("dpvn_collection");
requestLogs.insertOne({
body: EJSON.parse(payload.body.text()),
query: payload.query
}).then(result => {
})
};
import * as functions from 'firebase-functions';
console.log('I am a log entry0!');
const admin = require('firebase-admin');
admin.initializeApp(functions.config().firebase);
console.log('I am a log entry1!');
export const onMessageCreate = functions.database
.ref('/users/{userId}/totalScore')
.onUpdate((change) => {
console.log('I am a log entry2!');
//var a = admin.firestore().collection('/users');
})
I have deployed the function and I can see it in the console. But the function is not executed when totalScore is updated in the database....
Your database is Firestore but you use a Cloud Function that is triggered by an update in the Realtime Database. These are two different Firebase services and you need to change your code accordingly.
The following code will work:
const functions = require('firebase-functions');
const admin = require('firebase-admin');
admin.initializeApp();
exports.onMessageCreate = functions.firestore
.document('users/{userId}')
.onUpdate((change, context) => {
// Get an object representing the document
const newValue = change.after.data();
// ...or the previous value before this update
const previousValue = change.before.data();
if (newValue.totalScore !== previousValue.totalScore) {
console.log('NEW TOTAL SCORE');
}
return null;
//I guess you are going to do more than just logging to the console.
//If you do any asynchronous action, you should return the corresponding promise, see point 3 below
//For example:
//if (newValue.totalScore !== previousValue.totalScore) {
// return db.collection("score").doc(newValue.name).set({score: newValue.totalScore});
//}
});
Note that:
You cannot trigger the onUpdate Cloud Function when a specific field of the document changes. The Cloud Function will be triggered when any field of the Firestore document changes. But you can detect which field(s) have changed, as shown in the above code.
Since version 1.0 you have to initialize with admin.initializeApp();, see https://firebase.google.com/docs/functions/beta-v1-diffList
You need to indicate to the platform when the Cloud Function has finished executing: Since you are not executing any asynchronous operation in your Cloud Function you can use return null;. (For more details on this point, I would suggest you watch the 3 videos about "JavaScript Promises" from the Firebase video series: https://firebase.google.com/docs/functions/video-series/).
I think the update is checked on the ref not on the child
Try this
export const onMessageCreate = functions.database
.ref('/users/{userId}')
.onUpdate((change) => {
console.log('I am a log entry2!');
//var a = admin.firestore().collection('/users');
})
You get the old and new values of the snapshot at that location
If you are using Cloud Firestore then your listener is incorrect. In your case, you are specifying a listener for Realtime Database. We extract firestore from the functions and specify the path to the document we want to have a listener on:
import * as functions from 'firebase-functions';
const admin = require('firebase-admin');
admin.initializeApp(functions.config().firebase);
export const onMessageCreate = functions.firestore
.document('users/{userId}')
.onUpdate((change, context) => {
console.log(change.before.data()); // shows the document before update
console.log(change.after.data()); // shows the document after change
return;
})
I'm very new to React and Firebase. I'm trying to display the object newData as mentioned in the code. I've pushed in a value but later it shows the error in the screen attached.
I'm creating a menu app so I want to add menu into the firebase and also in the mean time return the current menu as well. How could I return from the firebase? How can I update or delete the data already present in the object in firebase? Is there any way to access an object that I had uploaded before? Suppose I push a menu with dishes and price and then how could I delete it or update it. (each specific dish)
Image of the database is attached.
componentWillMount(){
/* Create reference to messages in Firebase Database */
let messagesRef = fire.database().ref('vendor/'+this.state.Day+'/'+this.state.Vendor+'/dishname').orderByKey().limitToLast(100);
messagesRef.on('child_added', snapshot => {
/* Update React state when message is added at Firebase Database */
let message1 = { text: snapshot.val(), id: snapshot.key };
this.setState({ messages: [message1].concat(this.state.messages) });
})
}
addMessage(e){
let messagesR = fire.database().ref('vendor/'+this.state.Day+'/'+this.state.Vendor+'/dishname').orderByKey().limitToLast(100);
messagesR.on('child_added', snapshot => {
/* Update React state when message is added at Firebase Database */
let message1 = { text: snapshot.val(), id: snapshot.key };
this.setState({ messages: [message1].concat(this.state.messages) });
})
var newData={
Type: this.inputE3.value,
Dish: this.inputEl.value,
Price : this.inputE2.value
}
fire.database().ref('vendor/'+this.state.Day+'/'+this.state.Vendor+'/dishname').push(newData);
this.inputEl.value = '';
this.inputE2.value = '';
this.inputE3.value = '';
}