Synnefo

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from functools import wraps

from synnefo.plankton.backend import ImageBackend

from contextlib import contextmanager

def plankton_method(func):

    """Decorator function for API methods using ImageBackend.

    Decorator function that creates and closes an ImageBackend, needed

    by all API methods that handle images.

    """

    @wraps(func)

    def wrapper(request, *args, **kwargs):

        with image_backend(request.user_uniq) as backend:

            request.backend = backend

            return func(request, *args, **kwargs)

    return wrapper

@contextmanager

def image_backend(user_id):

    """Context manager for ImageBackend"""

    backend = ImageBackend(user_id)

    try:

        yield backend

    finally:

        backend.close()