I saw 'streaming' in the title and assumed you were going to use Flask's support for streaming (http://flask.pocoo.org/docs/patterns/streaming/). It allows you to send an HTTP response gradually, using a Python generator. It's useful when:
1) You cannot know the whole response at the time of the request (e.g. streaming news updates).
2) It's computationally expensive to calculate the whole response, and you don't want to make the user wait and/or calculate something that ends up not being used (e.g. if the user cancels the request).
3) You want to save bandwidth. If I were streaming music to you, and allowed you to switch tracks whenever you wanted, then I might not want your browser to start downloading the entire track (faster-than-real-time) when you click play. If I did, and you only listen to half-songs, then I would use twice as much bandwidth. I could release in shorter chunks and put a sleep or something before the yield in the generator function.
This seems like an odd way to do music streaming, I feel like you'd be better off dumping MP3 files in a folder and taking advantage of the media streaming support in nginx or Apache or similar.
Or, you can look at psobot's implementation of a streaming music app in forever.fm (http://blog.petersobot.com/introducing-forever-fm). The short version of it is that he uses a Python generator to generate frames, passes them through LAME, and then has Tornado hand out the music one frame at a time.
>> It’s the best practice to use a package instead of a
>> module for larger applications in Flask instead of a
>> single python file.
For something as small as this, i'd stay 1 single file. Keep it simple.
If the app gets bigger, at the point where 1 file is becoming painful (and not before) it's trivial to refactor to a module. If you're a single person team, that point may be wayyy further down the line than you'd think.
Keep it simple as possible, you're safe knowing that it's trivial to grow -> module -> blueprints and so on.
We made this mistake at a hackathon. Everything worked fine on dev machines, with the unsafe webserver built into flask.
When we tried to move it to a real server with wsgi, it stopped working. Users shouldn't have write access to the folder your code is in, and by default, they won't!
1) You cannot know the whole response at the time of the request (e.g. streaming news updates). 2) It's computationally expensive to calculate the whole response, and you don't want to make the user wait and/or calculate something that ends up not being used (e.g. if the user cancels the request). 3) You want to save bandwidth. If I were streaming music to you, and allowed you to switch tracks whenever you wanted, then I might not want your browser to start downloading the entire track (faster-than-real-time) when you click play. If I did, and you only listen to half-songs, then I would use twice as much bandwidth. I could release in shorter chunks and put a sleep or something before the yield in the generator function.