Node.js从数组表达流

Question

I'm building an app which i need to stream data to client, my data is simply an array of objects . this is the for loop which makes the array

   for(let i =0;i<files.length;i++){
      try {
        let file = files[i]
        var musicPath = `${baseDir}/${file}`
        let meta = await getMusicMeta(musicPath)
        musics.push(meta)
    }

right now I wait for the loop to finish it's works then I send the whole musics array to client, I want to use stream to send musics array one by one to client instead of waiting for the loop to finish

Answer 1

Use scramjet and send the stream straight to the response:

const {DataStream} = require("scramjet");
// ...

response.writeHead(200);
DataStream.fromArray(files)
    // all the magic happens below - flow control
    .map(file => getMusicMeta(`${baseDir}/${file}`))
    .toJSONArray()
    .pipe(response);

Scramjet will make use of your flow control and most importantly - it'll get the result out faster than any other streaming framework.

Edit: I wrote a couple lines of code to make this use case easier in scramjet. :)