如何获取保存在临时目录中的视频的 url

Question

我需要将视频文件保存到临时目录并保存对它的引用 URL。目前我已经尝试使用 fileManager 创建一个临时目录，然后 createFile(atPath: tempDirString, contents: vidData, attributes: nil)。但我不能/无法保存对文件的完整引用。

我尝试过的：

                                PHCachingImageManager().requestAVAsset(forVideo: (cell?.assetPH)!, options: nil) { (avAsset, _, _) in
                                if let avAsset = avAsset {
                                    print(avAsset, " the avasset?")
                                    //                                vidAVAsset = avAsset

                                    let avPlayerItem = AVPlayerItem(asset: avAsset)
                                    let avPlayer = AVPlayer(playerItem: avPlayerItem)
                                    print(avPlayer, "<-- good?")

                                    let finalURL = self.urlOfCurrentlyPlayingInPlayer(player: avPlayer)
                                    print(finalURL, "<-- finalURL YEAH EYAHY YEAH?!?!?")
//                                    newUserTakenVideo.videoURL = finalURL

                                    let url = self.addVidToTempURL(vidURL: finalURL!)
                                    newUserTakenVideo.videoURL = url
                                    //                                let newUserTakenVideo = SelectedMedia(videoURL: finalURL, phAsset: (cell?.assetPH)!, thumbnailImg: (cell?.imageView.image)!, uniqueCellID: indexPath)
//                                    GlobalSharedData.shared.arrayOfCurrentCreateMedia.append(newUserTakenVideo)
                                } else {
                                    print("did noot work")
                                }
                            }

这是调用的函数：

       func addVidToTempURL(vidURL: URL) -> URL? {
            let fileManager = FileManager.default
            let tempDir = fileManager.temporaryDirectory
            let tempDirString = tempDir.path
            do {

                print( "tempDir: \(tempDir)" )
                print( "tempDirString: \(tempDirString)" )
                if fileManager.fileExists(atPath: tempDirString ) {
                    print( "tempDir exists" )
                    do {
                        try fileManager.createDirectory( at: tempDir, withIntermediateDirectories: true, attributes: nil )
                        print( "tempDir created" )
                        if fileManager.fileExists(atPath: tempDirString ) {
                            print( "tempDir exists" )
                            let vidData = try Data(contentsOf: vidURL)
                            fileManager.createFile(atPath: tempDirString, contents: vidData, attributes: nil)
                            print(tempDirString, " the stringfsdsda")
//                            fileManager.urls(for: fileManager.temporaryDirectory, in: fileManager.)
                            let url = URL(string: tempDirString)
                            return url
                        } else {
                            print( "tempDir STILL DOES NOT exist" )
                            return nil
                        }
                    } catch {
                        print( "tempDir NOT created" )
                        return nil
                    }
                } else {
                    print( "tempDir DOES NOT exist" )
                    do {
                        try fileManager.createDirectory( at: tempDir, withIntermediateDirectories: true, attributes: nil )
                        print( "tempDir created" )
                        if fileManager.fileExists(atPath: tempDirString ) {
                            print( "tempDir exists" )
                            let vidData = try Data(contentsOf: vidURL)
                            fileManager.createFile(atPath: tempDirString, contents: vidData, attributes: nil)
                            print(tempDirString, " the fsdfdsdfsdfsfsd")
                            let url = URL(string: tempDirString)
                            return url
                        } else {
                            print( "tempDir STILL DOES NOT exist" )
                            return nil
                        }
                    } catch {
                        print( "tempDir NOT created" )
                        return nil
                    }
                }
            }

        }

如何获取此文件位置的 URL 引用？

感谢您的帮助，如果需要，可以添加更多信息。谢谢，我

Answer 1

由于您似乎不希望您的文件对用户可见或在应用启动之间保留，因此 Temporary directory 听起来非常适合您的用例：

var tempVideoFileUrl: URL {
    return FileManager.default.temporaryDirectory.appendingPathComponent("my_video_name")
}

func storeVideoToTemporaryFolder(videoData: Data) {
    guard !FileManager.default.fileExists(atPath: tempVideoFileUrl.path) else {
        return
    }
    do {
        try videoData.write(to: tempVideoFileUrl)
    }
    catch {
        fatalError()
    }
}

func loadVideoFromTemporaryFolder() -> Data? {
    if let data = try? Data(contentsOf: tempVideoFileUrl) {
        return data
    }
    return nil
}

值得一提的是，系统可能（并且很可能会）在应用退出后清除此目录。建议您在不再需要任何临时目录/文件后删除它们。

因此，在您的情况下，您可以在完成上传到 Firebase 存储后将其删除：

func deleteVideoFromTemporaryFolder() {
    do {
        try FileManager.default.removeItem(at: videoFileUrl)
    }
    catch {
        fatalError()
    }
}

如果您希望在应用启动之间保留文件，您可以使用 Application Support directory。但由于 Application Support 和 Documents 目录会自动备份，您可能希望通过设置 URL 的 isExcludedFromBackupKey 键将文件从 iCloud 备份中排除：

var applicationSupportVideoFileUrl: URL {
    let applicationSupportFolderUrl = try! FileManager.default.url(for: .applicationSupportDirectory, in: .userDomainMask, appropriateFor: nil, create: true)
    return applicationSupportFolderUrl.appendingPathComponent("my_video_name")
}

func excludeFromCloudBackup(url: URL) {
    var targetUrl = url
    var isAlreadyExcludedFromBackup: Bool
    do {
        let storedRessourceValues = try targetUrl.resourceValues(forKeys: [URLResourceKey.isExcludedFromBackupKey])
        isAlreadyExcludedFromBackup = storedRessourceValues.isExcludedFromBackup ?? false
    }
    catch {
        fatalError()
    }
    guard !isAlreadyExcludedFromBackup else {
        return
    }
    var ressourceValues = URLResourceValues()
    ressourceValues.isExcludedFromBackup = true
    do {
        try targetUrl.setResourceValues(ressourceValues)
    }
    catch {
        fatalError()
    }
}

编辑：要从您的 PHAsset 中获取数据，这应该可以：

import Photos

func loadVideoData(phAsset: PHAsset, completion: @escaping (Data?)->()) {
    guard phAsset.mediaType == .video else {
        return completion(nil)
    }
    let options = PHVideoRequestOptions()
    options.isNetworkAccessAllowed = true
    options.deliveryMode = .highQualityFormat
    PHCachingImageManager().requestAVAsset(forVideo: phAsset, options: options) { (avAsset, _, _) in
        guard let avUrlAsset = avAsset as? AVURLAsset else {
            return
        }
        var videoData: Data?
        do {
            videoData = try Data(contentsOf: avUrlAsset.url)
        } catch {
            fatalError()
        }
        DispatchQueue.main.async {
            completion(videoData)
        }
    }
}

然后只需调用此方法并将您的视频存储在临时文件夹中：

loadVideoData(phAsset: yourPhAsset) { [weak self] videoData in
    guard let strongSelf = self else { return }
    guard let videoData = videoData else {
        return
    }
    strongSelf.storeVideoToTemporaryFolder(videoData: videoData)
}