Question

我正在尝试使用Meteor和Meteor FS Collections将所有wav文件转码为mp3。当我将wav文件上传到上传器时，我的代码可以工作 - 也就是说它会将wav转换为mp3并允许我播放该文件。但是，我正在寻找一个流星解决方案，如果文件是一个wav并存在于某个目录中，它将转码并将文件添加到数据库中。根据Meteor FSCollection，如果文件已经存储，应该是可能的。这是他们的示例代码：* GM用于ImageMagik，我用ffmpeg替换gm并从atmosphereJS安装了ffmpeg。

Images.find().forEach(function (fileObj) {
  var readStream = fileObj.createReadStream('images');
  var writeStream = fileObj.createWriteStream('images');
  gm(readStream).swirl(180).stream().pipe(writeStream);
});

我正在使用Meteor-CollectionFS [https://github.com/CollectionFS/Meteor-CollectionFS]-

if (Meteor.isServer) {
  Meteor.startup(function () {
        Wavs.find().forEach(function (fileObj) {
      var readStream = fileObj.createReadStream('.wavs/mp3');
      var writeStream = fileObj.createWriteStream('.wavs/mp3');
      this.ffmpeg(readStream).audioCodec('libmp3lame').format('mp3').pipe(writeStream);
      Wavs.insert(fileObj, function(err) {
      console.log(err);
    });
      });
      });
}

这是我的FS.Collection和FS.Store信息。目前，所有内容都存在于一个JS文件中。

Wavs = new FS.Collection("wavs", {
  stores: [new FS.Store.FileSystem("wav"),
    new FS.Store.FileSystem("mp3",

    {
      path: '~/wavs/mp3',
      beforeWrite: function(fileObj) {
        return {
          extension: 'mp3',
          fileType: 'audio/mp3'
        };
      },
      transformWrite: function(fileObj, readStream, writeStream) {
        ffmpeg(readStream).audioCodec('libmp3lame').format('mp3').pipe(writeStream);
      }
    })]
});

当我尝试将文件插入服务器端的数据库时，我收到此错误：MongoError：E11000重复键错误索引：

否则，如果我将wav文件放入目录并重新启动服务器，则没有任何反应。我是流星的新手，请帮忙。谢谢。

Answer 1

Error is clear. You're trying to insert a next object with this same (duplicated) id, here you should first 'erase' the id or just update the document instead of adding the new one. If you not provide the _id field, it will be automatically added.

delete fileObj._id;
Wavs.insert(fileObj, function(error, result) {
});

See this How do I remove a property from a JavaScript object?

Why do you want to convert the files only on startup, I mean only one time? Probably you want to do this continuously, if yes then you should use this:

Tracker.autorun(function(){
    //logic
});

在启动时使用Meteor FS Collections将wav转换为mp3

1 个答案: