Swift 本地音乐assetURL转本地路径

中间鸽了两天，产品又给了新的需求，获取本地音乐并添加到视频中去。08的时候已经获取到本地音乐了，但是发现本地音乐的assetURL路径添加到视频的时候出现问题，需要把它转为本地路径。网上查到AVAssetExportSessionexport方法，由于是OC的，这里把它转为swift.
代码如下：

let everything = MPMediaQuery()
let itemsFromGenericQuery = everything.items
for song in itemsFromGenericQuery! {
      let songTitle = song.value(forProperty: MPMediaItemPropertyTitle) as! String
      let url = song.value(forProperty: MPMediaItemPropertyAssetURL)
      let songAsset = AVURLAsset.init(url: url as! URL)
      let fileManager = FileManager.default
      let dirs = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)
      let documentsDirectoryPath = dirs.first
      let exporter = AVAssetExportSession.init(asset: songAsset, presetName: AVAssetExportPresetAppleM4A)
      exporter?.outputFileType = "com.apple.m4a-audio"
      let exportFile = documentsDirectoryPath?.appending(songTitle + ".m4a")
      if fileManager.fileExists(atPath: exportFile!) {
          try? fileManager.removeItem(at: URL.init(string: exportFile!)!)
      }
      let exportURL = URL.init(fileURLWithPath: exportFile!)
      exporter?.outputURL = exportURL
      exporter?.exportAsynchronously(completionHandler: {
          print(exporter!.status)
      }
      print(path!)
      print(exportURL)
}

最后可以查看本地音乐的assetURL和本地路径

本地音乐.png