How to upload multiple files to Firebase?

Question

Is there a way to upload multiple files to Firebase storage. It can upload single file within single attempt as follows.

fileButton.addEventListener(\'chang         


        

Answer 1

Firebase Storage uses Promise, so you can use Promises to achieve it.

Here's the firebase blog article that covers this subject: Keeping our Promises (and Callbacks)

---

Give Promise.all() an "Array of Promises"

Promise.all(
  // Array of "Promises"
  myItems.map(item => putStorageItem(item))
)
.then((url) => {
  console.log(`All success`)
})
.catch((error) => {
  console.log(`Some failed: `, error.message)
});

Upload each file and return a Promise

putStorageItem(item) {
  // the return value will be a Promise
  return firebase.storage().ref("YourPath").put("YourFile")
  .then((snapshot) => {
    console.log('One success:', item)
  }).catch((error) => {
    console.log('One failed:', item, error.message)
  });
}

YourPath and YourFile can be carried with myItems array (thus the item object).

I omitted them here just for readability, but you get the concept.

Answer 2

all the promises get messy pretty quickly, why not use async and await instead?

Here, I have a function that keep tracks of all the images selected from the input/file control to be uploaded:

let images =[];
let imagePaths=[];

const trackFiles =(e)=>{
    images =[];
    imagePaths =[];
    for (var i = 0; i < e.target.files.length; i++) {
        images.push(e.target.files[i]);
    }
}

And I have another function that will be triggered by a button that the user will click on when ready to do the actual upload:

const uploadFiles =()=>{
    const storageRef = storage.ref();

    images.map(async img =>{
        let fileRef = storageRef.child(img.name);
        await fileRef.put(img);
        const singleImgPath = await fileRef.getDownloadURL();
        imagePaths.push(singleImgPath);

        if(imagePaths.length == images.length){
            console.log("got all paths here now: ", imagePaths);
        }
    })
}

We basically loop through each image and perform the upload, and push the image paths into a separate imagePaths array one by one as each of them gets finished at its own pace, I then grab all the paths once we know they are all done by comparing the length of the images and their final paths.