Choose firestore subcollection when connecting component to redux with react-redux-firebase

问题

I am using react-redux-firebase's fireStoreConnect() middleware with a screen in my react-native mobile app. At the time of connecting the component to the redux store, I want to specify the firestore sub-collection I connect to, which depends on the user that is navigating the app.

How should I specify the collection in firestoreConnect? The user id is in the redux store.

MWE:

import React, { Component } from 'react';
import { View, Text } from 'react-native';
import { compose } from 'redux';
import { connect } from 'react-redux'
import { firestoreConnect } from 'react-redux-firebase';

class PhotosScreen extends Component {
  render() {
    return (
      <View>
        <Text> i plan the use this.props.images here </Text>
      </View>
    );
  }
}

const mapStateToProps = (state) => {

    // reference the subcollection of the user
    const images = state.firestore.data.images;

    return {
        images: images,
    }
}

export default compose(
    firestoreConnect([
        {
            collection: 'users',
            doc: "HOW DO I GET THE USERS ID HERE? IT IS IN REDUX STORE",
            subcollections: [{ collection: 'images' }]
        }
    ]),
    connect(mapStateToProps),
)(PhotosScreen)

回答1:

In 1.x

const enhance = compose(
  connect(
    (state) => ({
      someKey: state.someData
    })
  ),
  firebaseConnect(
    (props, firebaseInstance) => [
      { path: `${props.someKey}/someData` }
    ]
  )
)

In 2.x

firebaseConnect(
  (props, store) => [
    { path: `${store.getState().someKey}/someData` }
  ]
)

Note how the 2nd argument in firebaseConnect changes from firebaseInstance to store from v1 to v2.

This should get you what you need.

回答2:

Firestore (and all NoSQL databases) follow an alternating "(parent) collection / document / collection / document ..." hierarchical pattern. To synchronize a React component to subcollections and documents below the parent firestore collection, you need to pass the subcollection/subdocument hierarchy information as props to firestoreConnect.

import React, { Component } from 'react';
import { View, Text } from 'react-native';
import { compose } from 'redux';
import { connect } from 'react-redux'
import { firestoreConnect } from 'react-redux-firebase';

class PhotosScreen extends Component {
  render() {
    return (
      <View>
        <Text> i plan the use this.props.images here </Text>
        {images && images.length ? <div> render your images here using this.props.images and images.map </div> : <p>No images</p>}
      </View>
    );
  }
}

const mapStateToProps = (state) => {


    return {
        images  : state.firestore.data.images, // reference the subcollection of the user
        userId  : state.firestore.auth.uid     // assuming the 'doc id' is the same as the user's uid
    }                                          
}

export default compose(
    firestoreConnect((props) => 

        if (!props.userId) return []                 // sync only if the userId is available (in this case, if they are authenticated)
        return [
            {
               collection     : 'users',             // parent collection
               doc            : props.userId,        // sub-document
               subcollections : [
                      {collection : 'images'}        // sub-collection
               ],
               storeAs        : 'images'
            }
         ]
    }),
    connect(mapStateToProps),
)(PhotosScreen)

来源：https://stackoverflow.com/questions/54726654/choose-firestore-subcollection-when-connecting-component-to-redux-with-react-red

标签

redux

react-redux

google-cloud-firestore

react-redux-firebase