I am working on a front end project with React and Firebase.
I would like to create a database where registered users can save their recipes by clicking on the RecipeCard button.
However with a click on another card, the contents of the field are overwritten and not added to the main recipeDb array.
Is there a solution?
here the img of my db
And here the code:
const dbFavorites = (e) => {
const recipeDb = [
{
Recipe: title,
Id: id,
Source: source,
},
];
fire.auth().onAuthStateChanged((user) => {
if (user) {
const dbAdd = fire
.firestore()
.collection("User-favorites" + user.uid)
.doc(user.uid)
.update({ recipeDb });
}
});
};
The function dbFavorites is used in the button:
<button
type="button"
onClick={() => {
dbFavorites();
}}
>
I state that FieldValue.arrayUnion gives me an error and I don'have a backend...
Update: I tried to use arrayUnion in this way (instead of the previous function):
const dbFavorites = (e) => {
const recipeDb = [
{
Recipe: title,
Id: id,
Source: source,
},
];
fire.auth().onAuthStateChanged((user) => {
if (user) {
const dbAdd = fire
.firestore()
.collection("User-favorites" + user.uid)
.doc(user.uid)
.update({ fav: fire.firestore.FieldValue.arrayUnion(recipeDb) });
}
});
};
Related
I am working on an edit page, where I use the ID to get current data, and then update it,
when I try to check if data is Manual or Automatic in the select tag, does not autoselect properly based on the value fetch from the database.
import {Select} from "#mui/material";
const [car, setCar] = React.useState({});
let {
id
} = useParams();
useEffect(() => {
async function getCar() {
await axios_auth
.get("/car/" + id)
.then((res) => {
setCar(res.data);
})
.catch((err) => {
console.log(err);
});
}
getCar();
}, [id]);
console.log(car.transmission) // Manual
<Select
defaultValue={car.transmission} // is undefined, whene I use Manually for example "Manual", it is autoselected
}
label = "transmission"
onChange = {
(val) => {
formik.setFieldValue("transmission", val);
}
}
name = "transmission"
I'm trying to make a Tweets Application with React and Firebase and I have been suffering when trying to get info from more than 1 collection.
So this is the story:
I get the tweets using onSnapshot. All fine here
I need more info from 2 other collections: user_preferences and user_photo, so I use .get() within the onSnapshot
For managing asynchronism, I resolve my 2 promises before returning the tweet data + details data object for my map function.
I made a console.log of my mappedTweet and the values are OKEY. Here I can see the tweet data + details data
But my STATE "tweets" just have an array of undefined objects =(. It shows the right number of rows accoroding to my Tweets collection but rows of undefined data, and not the rows of my mappedTweets objects. Why?
Can anyone shed some light?
useEffect(() => {
//------------getting the TWEETS with onSnapshot()-------------
const cancelSuscription = firestore
.collection('tweets')
.onSnapshot((snapshot) => {
const promises = [];
const tweetsMapped = snapshot.docs.map((doc) => {
let tweetAndAuthor;
const tweetMappped = {
text: doc.data().text,
likes: doc.data().likes,
email: doc.data().email,
created: doc.data().created,
uid: doc.data().uid,
id: doc.id,
};
let authorPreference, authorPhoto;
const userPreferencePromise = firestore
.collection('user_preferences')
.where('uid', '==', tweetMappped.uid)
.get();
const userPhotoPromise = firestore
.collection('user_photos')
.where('id', '==', tweetMappped.uid)
.get();
promises.push(userPreferencePromise);
promises.push(userPhotoPromise);
//------------getting the AUTHOR USER PREFERENCES with .get()-------------
userPreferencePromise.then((snapshot2) => {
authorPreference = snapshot2.docs.map((doc) => {
return {
username: doc.data().username,
color: doc.data().color,
};
});
});
//------------getting the AUTHOR PHOTO with .get()-------------
userPhotoPromise.then((snapshot3) => {
authorPhoto = snapshot3.docs.map((doc) => {
return {
photoURL: doc.data().photoURL,
};
});
});
Promise.all(promises).then((x) => {
return {
...tweetMappped,
author: authorPreference[0].username,
authorColor: authorPreference[0].color,
authorPhoto: authorPhoto[0].photoURL,
};
});
});
Promise.all(promises).then((x) => {
setTweets(tweetsMapped);
});
});
return () => cancelSuscription();
}, []);
Well, I made it work by changing the model I was using to retrieve the data from Firebase.
I was using an outer onSnapshot with nested promises (I think I was very near here), but now I'm using nested onSnapshots and now app is behaving as expected.
So this is the new useEffect
useEffect(() => {
let cancelUserPrefSuscription, cancelUserPhotoSuscription;
// First onSnapshot
const cancelTweetSuscription = firestore
.collection('tweets')
.onSnapshot((tweetSnapshot) => {
const list = [];
tweetSnapshot.docs.forEach((tweetDoc) => {
//Second onSnapshot
cancelUserPrefSuscription = firestore
.collection('user_preferences')
.where('uid', '==', tweetDoc.data().uid)
.onSnapshot((userPrefSnapshot) => {
userPrefSnapshot.docs.forEach((userPrefDoc) => {
//Third onSnapshot
cancelUserPhotoSuscription = firestore
.collection('user_photos')
.where('id', '==', tweetDoc.data().uid)
.onSnapshot((userPhotoSnapshot) => {
userPhotoSnapshot.docs.forEach((userPhotoDoc) => {
//Taking the whole data i need from all snapshots
const newData = {
id: tweetDoc.id,
...tweetDoc.data(),
author: userPrefDoc.data().username,
authorColor: userPrefDoc.data().color,
authorPhoto: userPhotoDoc.data().photoURL,
};
list.push(newData);
//Updating my state
if (tweetSnapshot.docs.length === list.length) {
setTweets(list);
}
});
});
});
});
});
});
return () => {
cancelTweetSuscription();
cancelUserPrefSuscription();
cancelUserPhotoSuscription();
};
}, []);
Edit: Fix from comments of above code
Author: #samthecodingman
For each call to onSnapshot, you should keep track of its unsubscribe function and keep an array filled with the unsubscribe functions of any nested listeners. When an update is received, unsubscribe each nested listener, clear the array of nested unsubscribe functions and then insert each new nested listener into the array. For each onSnapshot listener attached, a single unsubscribe function should be created that cleans up the listener itself along with any nested listeners.
Note: Instead of using this approach, create a Tweet component that pulls the author's name and photo inside it.
useEffect(() => {
// helper function
const callIt = (unsub) => unsub();
// First onSnapshot
const tweetsNestedCancelListenerCallbacks = [];
const tweetsCancelListenerCallback = firestore
.collection('tweets')
.onSnapshot((tweetSnapshot) => {
const newTweets = [];
const expectedTweetCount = tweetSnapshot.docs.length;
// cancel nested subscriptions
tweetsNestedCancelListenerCallbacks.forEach(callIt);
// clear the array, but don't lose the reference
tweetsNestedCancelListenerCallbacks.length = 0;
tweetsNestedCancelListenerCallbacks.push(
...tweetSnapshot.docs
.map((tweetDoc) => { // (tweetDoc) => Unsubscribe
const tweetId = tweetDoc.id;
//Second onSnapshot
const userPrefNestedCancelListenerCallbacks = [];
const userPrefCancelListenerCallback = firestore
.collection('user_preferences')
.where('uid', '==', tweetDoc.data().uid)
.limitToFirst(1)
.onSnapshot((userPrefSnapshot) => {
const userPrefDoc = userPrefSnapshot.docs[0];
// cancel nested subscriptions
userPrefNestedCancelListenerCallbacks.forEach(callIt);
// clear the array, but don't lose the reference
userPrefNestedCancelListenerCallbacks.length = 0;
//Third onSnapshot
const userPhotoCancelListenerCallback = firestore
.collection('user_photos')
.where('id', '==', tweetDoc.data().uid)
.limitToFirst(1)
.onSnapshot((userPhotoSnapshot) => {
const userPhotoDoc = userPhotoSnapshot.docs[0];
// Taking the whole data I need from all snapshots
const newData = {
id: tweetId,
...tweetDoc.data(),
author: userPrefDoc.data().username,
authorColor: userPrefDoc.data().color,
authorPhoto: userPhotoDoc.data().photoURL,
};
const existingTweetObject = tweets.find(t => t.id === tweetId);
if (existingTweetObject) {
// merge in changes to existing tweet
Object.assign(existingTweetObject, newData);
if (expectedTweetCount === newTweets.length) {
setTweets([...newTweets]); // force rerender with new info
}
} else {
// fresh tweet
tweets.push(newData);
if (expectedTweetCount === newTweets.length) {
setTweets(newTweets); // trigger initial render
}
}
});
userPrefNestedCancelListenerCallbacks.push(userPhotoCancelListenerCallback);
});
// return an Unsubscribe callback for this listener and its nested listeners.
return () => {
userPrefCancelListenerCallback();
userPrefNestedCancelListenerCallbacks.forEach(callIt);
}
})
);
});
// return an Unsubscribe callback for this listener and its nested listeners.
return () => {
tweetsCancelListenerCallback();
tweetsNestedCancelListenerCallbacks.forEach(callIt);
};
}, []);
Edit: Splitting the code in two components
Note: Changed limitToFirst(1) --> limit(1). Splitting the fetch logic in two components simplified the onSnapshot approach!
1.The Parent Component
useEffect(() => {
const tweetsUnsubscribeCallback = firestore
.collection('tweets')
.onSnapshot((tweetSnapshot) => {
const mappedtweets = tweetSnapshot.docs.map((tweetDoc) => {
return {
id: tweetDoc.id,
...tweetDoc.data(),
};
});
setTweets(mappedtweets);
});
return () => tweetsUnsubscribeCallback();
}, []);
2.The Child Component: Tweet
useEffect(() => {
// Helper Function
const unSubscribe = (unsub) => unsub();
//------------getting the AUTHOR USER PREFERENCE
const userPrefNestedUnsubscribeCallbacks = [];
const userPrefUnsubscribeCallback = firestore
.collection('user_preferences')
.where('uid', '==', tweet.uid)
.limit(1)
.onSnapshot((userPrefSnapshot) => {
userPrefNestedUnsubscribeCallbacks.forEach(unSubscribe); // cancel nested subscriptions
userPrefNestedUnsubscribeCallbacks.length = 0; // clear the array, but don't lose the reference
//------------getting the AUTHOR PHOTO
const userPhotoUnsubscribeCallback = firestore
.collection('user_photos')
.where('id', '==', tweet.uid)
.limit(1)
.onSnapshot((userPhotoSnapshot) => {
// Taking the whole data I need from all snapshots
setAuthor({
author: userPrefSnapshot.docs[0].data().username,
authorColor: userPrefSnapshot.docs[0].data().color,
authorPhoto: userPhotoSnapshot.docs[0].data().photoURL,
});
});
userPrefNestedUnsubscribeCallbacks.push(userPhotoUnsubscribeCallback);
});
return () => {
userPrefUnsubscribeCallback();
userPrefNestedUnsubscribeCallbacks.forEach(unSubscribe);
};
}, []);
Basically, you've pushed the promises to your promise array in the state they were before you you processed their data. You want to make use of the Promise.all(docs.map((doc) => Promise<Result>)) pattern here where each document should return a single Promise containing its final result. This then means that the Promise.all will resolve with Result[].
Note: If inside a Promise you are mutating a variable outside of the Promise (e.g. pushing to an array), that is generally a sign that you are doing something wrong and you should rearrange your code.
Here's a quick example of throwing this together:
useEffect(() => {
let unsubscribed = false;
//------------getting the TWEETS with onSnapshot()-------------
const cancelSuscription = firestore
.collection('tweets')
.onSnapshot((snapshot) => {
const tweetsMappedPromises = snapshot.docs.map((doc) => {
let tweetAndAuthor;
const tweetMappped = {
text: doc.data().text,
likes: doc.data().likes,
email: doc.data().email,
created: doc.data().created,
uid: doc.data().uid,
id: doc.id,
};
//------------getting the AUTHOR USER PREFERENCES with .get()-------------
const userPreferencePromise = firestore
.collection('user_preferences')
.where('uid', '==', tweetMappped.uid)
.limitToFirst(1)
.get()
.then((prefDocQuerySnapshot) => {
const firstPrefDoc = photoDocQuerySnapshot.docs[0];
const { username, color } = firstPrefDoc.data();
return { username, color };
});
//------------getting the AUTHOR PHOTO with .get()-------------
const userPhotoPromise = firestore
.collection('user_photos')
.where('id', '==', tweetMappped.uid)
.limitToFirst(1)
.get()
.then((photoDocQuerySnapshot) => {
const firstPhotoDoc = photoDocQuerySnapshot.docs[0];
return firstPhotoDoc.get("photoURL");
});
//--------------------assemble this result---------------------
return Promises.all([userPreferencePromise, userPhotoPromise])
.then(([authorPreference, authorPhoto]) => {
return {
...tweetMappped,
author: authorPreference.username,
authorColor: authorPreference.color,
authorPhoto: authorPhoto.photoURL,
};
});
});
Promise.all(tweetsMappedPromises)
.then((tweetsMapped) => {
if (unsubscribed) return; // ignore result, dealing with out of date data
setTweets(tweetsMapped);
})
.catch((err) => {
if (unsubscribed) return; // ignore result, dealing with out of date data
// important! handle errors
});
});
return () => {
unsubscribed = true;
cancelSuscription();
}
}, []);
Notes:
You may benefit from using async/await syntax here instead.
On new onSnapshot calls, snapshot.docChanges() can be used to make it more efficient and speed up rerenders by only updating the entries that have changed (e.g. added/removed/modified). You would use setTweets(previousTweetsMapped => /* newTweetsMapped */) for this.
I'm new to Firebase Realtime Database, and i'm trying to implement a search field that allow users to search for other users and view their profiles.
The Problem Is:
I want to make the search realTime(on each input change).but whenever a new request's sent, the old request is still working in the backend which's causing unexpected behavior,i've wrapped this functionality in a useEffect Hook,old sideEffects has to be cleaned up to make the query results predictable,how can i abort the previous request.
useSearchOwner Custom Hook:
const useSearchOwner = () => {
const [{ SearchValue, SearchResult, Search }, dispatch] = useReducer(
reducer,
{
SearchValue: "",
SearchResult: "",
Search: false,
}
);
const isFirstRender = useRef(true);
const onChangeHandler = (e) =>
dispatch({
type: ACTIONS.UPDATE_SEARCH_VALUE,
payload: { searchValue: e.target.value },
});
useEffect(() => {
if (isFirstRender.current) {
isFirstRender.current = false;
return;
}
dispatch({ type: ACTIONS.START_SEARCHING });
const DispatchQueryByResult = async () => {
const ArrayOfOwners = await FirebaseUtilityInstance.SearchOwnerResult(
SearchValue
);
dispatch({
type: ACTIONS.UPDATE_SEARCH_RESULT,
payload: { searchResult: ArrayOfOwners },
});
dispatch({ type: ACTIONS.STOP_SEARCHING });
return () => {
FirebaseUtilityInstance.SearchOwnerCleanup();
};
};
DispatchQueryByResult();
}, [SearchValue]);
useEffect(() => {
console.log(SearchResult);
}, [SearchResult]);
return {
onChangeHandler: onChangeHandler,
Query: SearchValue,
QueryResult: SearchResult,
isSearching: Search,
};
};
Firebase Method To Do Query:
SearchOwnerResult = async (Query) => {
const { firstName, lastName } = getFirstNameAndLastName(Query);
let ArrayOfOwners = [];
await this.Database()
.ref("users")
.orderByChild("UserType")
.equalTo("owner")
.once("value", (snapshot) => {
const OwnersContainer = snapshot.val();
const keys = Object.keys(OwnersContainer);
for (let i = 0; i < keys.length; i++) {
const CurrentOwner = OwnersContainer[keys[i]];
if (
CurrentOwner.FirstName === firstName ||
CurrentOwner.LastName === lastName
) {
ArrayOfOwners.push(OwnersContainer[keys[i]]);
}
}
});
return ArrayOfOwners;
};
I have a state where I store all the uuids of the posts. I am retrieving the uuids of the posts in useEffect() from firebase and looping through the array of uuids and retrieving all the posts that the user made but the posts state is returning an empty array.
useEffect(() => {
getData();
}, []);
const getData = () => {
setPosts([]);
setPostuuids([]);
firebase
.firestore()
.collection("users")
.doc(uid)
.get()
.then((doc) => {
setPostuuids(doc.data().posts);
});
postuuids.filter((postuuid) => {
firebase
.firestore()
.collection("posts")
.doc(postuuid)
.get()
.then((doc) => {
const image = doc.data().image;
const text = doc.data().text;
const userid = doc.data().uid;
const timestamp = doc.data().timestamp;
const username = doc.data().username;
const uuid = doc.data().uuid;
const name = doc.data().name;
const avatar = doc.data().avatar;
setPosts((prevPosts) => [
...prevPosts,
{
image: image,
timestamp: timestamp,
text: text,
name: name,
userid: userid,
uuid: uuid,
username: username,
avatar: avatar,
},
]);
});
});
};
your postuuids.filter run before request completed, so postuuids is empty.
you should use another useEffect() for postuuids.map():
useEffect(() =>{
postuuids.map((postuuid) => {
firebase
.firestore()
.collection("posts")
.doc(postuuid)
.get()
.then((doc) => {
const image = doc.data().image;
const text = doc.data().text;
const userid = doc.data().uid;
const timestamp = doc.data().timestamp;
const username = doc.data().username;
const uuid = doc.data().uuid;
const name = doc.data().name;
const avatar = doc.data().avatar;
setPosts((prevPosts) => [
...prevPosts,
{
image: image,
timestamp: timestamp,
text: text,
name: name,
userid: userid,
uuid: uuid,
username: username,
avatar: avatar,
},
]);
});
});
};
},[postuuids])
Use map method instead of filter to loop through a list.
Best Regards!
this is my react native + firebase project and i have got 2 questions:
How do you suggest to pass the id from one CV ?
How do i fetch only one CV from firebase, cause if i try this it gives me this error:
TypeError: undefined is not an object (evaluating 'querySnapshot.docs.map')]
fetching all the documents from the collection is fine
getCv: () => {
const id = "eccc137b-88be-470d-a0b8-c90b58a6473a"
return firebase
.firestore()
.collection('cvs')
.doc(id)
.get()
.then(function(querySnapshot) {
let cvs = querySnapshot.docs.map(doc => doc.data())
// console.log(doc.data())
return cvs
})
.catch(function(error) {
console.log('Error getting documents: ', error)
})
}
This is my fetchCV method
fetchCvs = async () => {
try {
const cvs = await this.props.firebase.getCv()
//const cvs = await this.props.firebase.getCvs()
//console.log(cvs)
this.setState({ DATA: cvs, isRefreshing: false })
} catch (e) {
console.error(e)
}
}
This is how i add one CV
onSubmit = async () => {
try {
const cv = {
photo: this.state.image,
title: this.state.title,
description: this.state.description,
salary: this.state.salary,
createdAt: new Date().toISOString()
}
this.props.firebase.uploadCv(cv)
this.setState({
image: null,
title: '',
description: '',
salary: '',
createdAt: ''
})
} catch (e) {
console.error(e)
}
}
uploadCv: cv => {
const id = uuid.v4()
const uploadData = {
id: id,
cvPhoto: cv.photo,
cvTitle: cv.title,
cvDescription: cv.description,
cvSalary: cv.salary,
cvCreatedAt: cv.createdAt
}
return firebase
.firestore()
.collection('cvs')
.doc(id)
.set(uploadData)
},
and This is how i implemented the deleteCv method
onDelete = async () => {
const cvId = {
id: this.state.title
}
//this.props.firebase.deleteItem(cv);
const deleteId = this.props.firebase.deleteItem(cv);
console.log(deleteId)
}
I have different error, when I try similar code in nodejs, but I think its the same reason. In line:
let cvs = querySnapshot.docs.map(doc => doc.data())
As you are using get on DocumentReference querySnapshot is instance of DocumentSnapshot which does not have property docs. I think you should use querySnapshot.data() first and than manipulate on data returned.
Or maybe you wanted to use get on collection, not on document, and than you will get QuerySnapshot object and .doc array will be available.