Download json file from firebase storage

问题

Let me restate my question. I have a vue.js app that uploads a json file to a bucket in my firebase storage. I need to download the file to use in my app but when I try to download a json file from firebase storage I get a "Uncaught (in promise) undefined" error.

What I would like to do is download the file back into an object to use in my app

Here is my code to download and read the file:

const storage = firebase.storage()
const storageRef = storage.ref()
const objectRef = storageRef.child('BUCKET/FILE_NAME.json')
objectRef.download(function (err, contents) {
    if (!err) {
        var jsObject = JSON.parse(contents.toString('utf8'))
        console.log('jsObject ', jsObject)
    }
})

UPDATE: Here is my entire code. I check the DB for an active course. If found, I want to grab that course from storage and built out my object from its contents.

getActiveCourse({ dispatch }, { cid, user }) {
    return new Promise((res, rej) => {
        let userActiveCourse = []
        let archivedUserCourses = []
        let currentCourseRef = db.collection('currentcourses')
        currentCourseRef = currentCourseRef.where('cid', '==', cid)
        currentCourseRef = currentCourseRef.where('user', '==', user.uid)
        currentCourseRef.get().then(snapshot => {
            if (!snapshot.empty) {
                snapshot.forEach(doc => {
                    let course = doc.data()
                    course.id = doc.id
                    if (course.status == 'active') {

                        // WE FOUND AN ACTIVE COURSE. NOW LETS DOWNLOAD IT AND READ IT INTO AN ARRAY
                        const storage = firebase.storage()
                        const storageRef = storage.ref()
                        const objectRef = storageRef.child('BUCKET/FILE_NAME.json')
                        objectRef.download(function (err, contents) {
                                 if (!err) {
                                     var jsObject = JSON.parse(contents.toString('utf8'))
                                 }
                             })
                        userActiveCourse.push(course.course)
                    } else {
                        archivedUserCourses.push(course.course)
                    }
                })
            }

        }).then(() => {
            dispatch('addUserActiveCourse', userActiveCourse)
            dispatch('addArchivedUserCourses', archivedUserCourses)

            res()
        }).catch(() => rej())
    })
},

回答1:

Steps to start a Firebase project

Open the Firebase console. Click “CREATE NEW PROJECT”.

The “Create a project” window opens.
The start screen of the Firebase console opens.
The “Enter app details” screen opens.
Continue the configuration by following the on-screen instruction.
Check the server key after the project is created.
Down the server key and store it on your local drive for now.

Now that we have installed dependencies and created a Firebase project, just create an index.js file and paste the below code. Don’t worry, we will go over the code in detail, to understand what is happening.

回答2:

Here was the solution for anyone else needing help with this type of issue.

const storage = firebase.storage()
const storageRef = storage.ref()
const objectRef = storageRef.child(course.storageRef)
objectRef.getDownloadURL().then((url) => {
    axios.get(url).then((response) => {
        let activeCourse = response.data
        userActiveCourse.push(activeCourse)
    })
})

来源：https://stackoverflow.com/questions/66065378/download-json-file-from-firebase-storage

标签

javascript

firebase

Vue.js

google-cloud-storage