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# -*- coding: utf-8 -*-
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# Moovida - Home multimedia server
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# Copyright (C) 2006-2009 Fluendo Embedded S.L. (www.fluendo.com).
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# This file is available under one of two license agreements.
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# This file is licensed under the GPL version 3.
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# See "LICENSE.GPL" in the root of this distribution including a special
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# exception to use Moovida with Fluendo's plugins.
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# The GPL part of Moovida is also available under a commercial licensing
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# agreement from Fluendo.
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# See "LICENSE.Moovida" in the root directory of this distribution package
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# for details on that license.
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# Author: Olivier Tilloy <olivier@fluendo.com>
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Basic utility functions.
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from elisa.core import common
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from elisa.core.utils import defer, caching
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def get_and_cache_image(image_uri):
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Get and cache an image for which we know a resource provider is available.
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If the image is local or already cached on disk, do not perform the
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The get request that may be performed to obtain the image is expected to
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return a L{elisa.plugins.base.models.media.RawDataModel}.
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@param image_uri: the URI of the image
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@type image_uri: L{elisa.core.media_uri.MediaUri}
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@return: a deferred fired when the image was cached, with the full path to
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@rtype: L{elisa.core.utils.defer.Deferred} with C{unicode}
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cache_file = caching.get_cached_image_path(image_uri)
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if os.path.exists(cache_file):
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return defer.succeed(cache_file)
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def cache_data_to_file(model, cache_file):
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return caching.cache_to_file(model.data, cache_file)
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model, dfr = common.application.resource_manager.get(image_uri)
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dfr.addCallback(cache_data_to_file, cache_file)
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def get_and_cache_thumbnail(item, thumbnail_uri):
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Get and cache a thumbnail for a given item.
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If the thumbnail is local or already cached on disk, do not perform the
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The given thumbnail URI is assumed to have a corresponding resource
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provider registered and available (in case it is not a local resource).
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The get request that may be performed to obtain the thumbnail is expected
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to return a L{elisa.plugins.base.models.media.RawDataModel}.
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@param item: any model for which we want to request a thumbnail
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@param thumbnail_uri: the URI to the distant thumbnail
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@type thumbnail_uri: L{elisa.core.media_uri.MediaUri}
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@return: a deferred fired when the thumbnail was cached, with the full path
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@rtype: L{elisa.core.utils.defer.Deferred} with C{unicode}
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# This is a two-level caching mechanism:
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# 1) First check if the item has a "thumbnail_path" attribute. If it does,
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# trust that the referenced thumbnail exists and is valid;
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# 2) If not, compute the thumbnail path and get it where needed.
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# Note: the reference to the local path of the thumbnail being stored
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# in the item's "thumbnail_path" attribute is a convention that was
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# historically used here and there in various places of the code.
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# Change where it is stored at your own risk! It may (or may not) break
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# thumbnailing in various places, depending on how it was first
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return defer.succeed(item.thumbnail_path)
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except AttributeError:
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def set_thumbnail_path(thumbnail_path, item):
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item.thumbnail_path = thumbnail_path
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dfr = get_and_cache_image(thumbnail_uri)
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dfr.addCallback(set_thumbnail_path, item)
added
removed
elisa/plugins/base/utils.py
