How to create in-memory file object

Question

I want to make a in-memory file to use in pygame mixer. I mean something like http://www.pygame.org/docs/ref/music.html#pygame.mixer.music.load which says load() method supports file object.

import requests
from pygame import mixer

r = requests.get("http://example.com/some_small_file.mp3")
in_memory_file = file(r.content) # something like this
mixer.music.init()
mixer.music.load(in_memory_file)
mixer.music.play()

Robi

Answer 1

You are probably looking for BytesIO or StringIO classes from Python io package, both available in python 2 and python 3. They provide a file-like interface you can use in your code the exact same way you interact with a real file.

StringIO is used to store textual data:

import io

f = io.StringIO("some initial text data")

BytesIO must be used for binary data:

import io

f = io.BytesIO(b"\x00\x00\x00\x00\x00\x00\x00\x00\x01\x01\x01\x01\x01\x01")

To store MP3 file data, you will probably need the BytesIO class. To initialize it from a GET request to a server, proceed like this:

import requests
from pygame import mixer
import io

r = requests.get("http://example.com/somesmallmp3file.mp3")
inmemoryfile = io.BytesIO(r.content)

mixer.music.init()
mixer.music.load(inmemoryfile)
mixer.music.play()

# This will free the memmory from any data
inmemoryfile.close()

Additional note: as both classes inherit from IOBase, they can be used as context manager with the with statement, so you don't need to manually call the close() method anymore:

import requests
from pygame import mixer
import io

r = requests.get("http://example.com/somesmallmp3file.mp3")

with io.BytesIO(r.content) as inmemoryfile:
    mixer.music.init()
    mixer.music.load(inmemoryfile)
    mixer.music.play()

Wendiewendin