ios - 使用 Google Firebase 同时上传多张图片

Question

我在 Swift iOS 项目中使用 Google Firebase。我的应用程序中有一部分用户从他们的设备中选择了多张照片进行上传。我正在尝试找到将他们一次选择的所有照片上传到 Firebase 存储的最佳做法。我知道如何上传一张照片。

我查看了文档并没有看到任何关于上传多个 NSData 对象的方法，所以我是否只需运行一个 for 循环并单独上传每个图像？

谢谢！感谢所有反馈。

Answer 1

Swift 3 这就是我将多个图像上传到 Firebase 的方式。我正在计算成功上传的数量，如果它等于提供的图像数量，那就是我调用完成处理程序的时候。

不确定这是否是最佳做法，但它有效！

import Foundation
import Firebase
import FirebaseDatabase
import FirebaseStorage

class UploadImages: NSObject{

static func saveImages(imagesArray : [UiImage]){

        Auth.auth().signInAnonymously() { (user, error) in
            //let isAnonymous = user!.isAnonymous  // true
            //let uid = user!.uid
            if error != nil{
                print(error)
                return
            }
            guard let uid = user?.uid else{
                return
            }

            uploadImages(userId: uid,imagesArray : imagesArray){ (uploadedImageUrlsArray) in
                print("uploadedImageUrlsArray: \(uploadedImageUrlsArray)")
            }
        }
    }


static func uploadImages(userId: String, imagesArray : [UIImage], completionHandler: @escaping ([String]) -> ()){
    var storage     =   Storage.storage()

    var uploadedImageUrlsArray = [String]()
    var uploadCount = 0
    let imagesCount = imagesArray.count

    for image in imagesArray{

        let imageName = NSUUID().uuidString // Unique string to reference image

        //Create storage reference for image
        let storageRef = storage.reference().child("\(userId)").child("\(imageName).png")


        guard let myImage = image else{
            return
        }
        guard let uplodaData = UIImagePNGRepresentation(myImage) else{
            return
        }

        // Upload image to firebase
        let uploadTask = storageRef.putData(uplodaData, metadata: nil, completion: { (metadata, error) in
            if error != nil{
                print(error)
                return
            }
            if let imageUrl = metadata?.downloadURL()?.absoluteString{
                print(imageUrl)
                uploadedImageUrlsArray.append(imageUrl)

                uploadCount += 1
                print("Number of images successfully uploaded: \(uploadCount)")
                if uploadCount == imagesCount{
                    NSLog("All Images are uploaded successfully, uploadedImageUrlsArray: \(uploadedImageUrlsArray)")
                    completionHandler(uploadedImageUrlsArray)
                }
            }

        })


        observeUploadTaskFailureCases(uploadTask : uploadTask)   
    }  
} 


//Func to observe error cases while uploading image files, Ref: https://firebase.google.com/docs/storage/ios/upload-files


    static func observeUploadTaskFailureCases(uploadTask : StorageUploadTask){
        uploadTask.observe(.failure) { snapshot in
          if let error = snapshot.error as? NSError {
            switch (StorageErrorCode(rawValue: error.code)!) {
            case .objectNotFound:
              NSLog("File doesn't exist")
              break
            case .unauthorized:
              NSLog("User doesn't have permission to access file")
              break
            case .cancelled:
              NSLog("User canceled the upload")
              break

            case .unknown:
              NSLog("Unknown error occurred, inspect the server response")
              break
            default:
              NSLog("A separate error occurred, This is a good place to retry the upload.")
              break
            }
          }
        }
    }

}

用法

let arrayOfImages : [UIImage] = [Image1, Image2, Image3]
UploadImages.saveImages(imagesArray: arrayOfImages)

Answer 2

@FrankVanPuffellen 在评论中回答...

“你确实只是循环并单独上传它们。如果你一次上传一个，你的 iOS 用户可能也会喜欢，这样他们就可以在中途中止上传，而不会丢失所有图像的进度。” ——弗兰克·范·普菲伦