Mercurial > libervia-backend
diff src/plugins/plugin_xep_0264.py @ 2513:2d3c9dcec384
plugin XEP-0264: thumbnails handling implementation
author | Goffi <goffi@goffi.org> |
---|---|
date | Fri, 02 Mar 2018 17:53:31 +0100 |
parents | |
children | 327bbbe793ce |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/plugins/plugin_xep_0264.py Fri Mar 02 17:53:31 2018 +0100 @@ -0,0 +1,181 @@ +#!/usr/bin/env python2 +# -*- coding: utf-8 -*- + +# SAT plugin for managing xep-0264 +# Copyright (C) 2009-2018 Jérôme Poisson (goffi@goffi.org) +# Copyright (C) 2014 Emmanuel Gil Peyrot (linkmauve@linkmauve.fr) + +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero General Public License as published by +# the Free Software Foundation, either version 3 of the License, or +# (at your option) any later version. + +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Affero General Public License for more details. + +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see <http://www.gnu.org/licenses/>. + +from sat.core.i18n import _ +from sat.core.constants import Const as C +from sat.core.log import getLogger +log = getLogger(__name__) +from twisted.internet import threads +from twisted.python.failure import Failure + +from zope.interface import implements + +from wokkel import disco, iwokkel + +from sat.core import exceptions +import hashlib +try: + from PIL import Image +except: + raise exceptions.MissingModule(u"Missing module pillow, please download/install it from https://python-pillow.github.io") + +try: + from twisted.words.protocols.xmlstream import XMPPHandler +except ImportError: + from wokkel.subprotocols import XMPPHandler + + +MIME_TYPE = u'image/jpeg' +SAVE_FORMAT = u'JPEG' # (cf. Pillow documentation) + +NS_THUMBS = 'urn:xmpp:thumbs:1' + +PLUGIN_INFO = { + C.PI_NAME: "XEP-0264", + C.PI_IMPORT_NAME: "XEP-0264", + C.PI_TYPE: "XEP", + C.PI_MODES: C.PLUG_MODE_BOTH, + C.PI_PROTOCOLS: ["XEP-0264"], + C.PI_DEPENDENCIES: ["XEP-0234"], + C.PI_MAIN: "XEP_0264", + C.PI_HANDLER: "yes", + C.PI_DESCRIPTION: _("""Thumbnails handling""") +} + + +class XEP_0264(object): + SIZE_SMALL = (250, 250) + SIZE_MEDIUM = (1024, 1024) + + def __init__(self, host): + log.info(_(u"Plugin XEP_0264 initialization")) + self.host = host + host.trigger.add("XEP-0234_buildFileElement", self._addFileThumbnails) + host.trigger.add("XEP-0234_parseFileElement", self._getFileThumbnails) + + def getHandler(self, client): + return XEP_0264_handler() + + ## triggers ## + + def _addFileThumbnails(self, file_elt, extra_args): + try: + thumbnails = extra_args[u'extra'][C.KEY_THUMBNAILS] + except KeyError: + return + for thumbnail in thumbnails: + thumbnail_elt = file_elt.addElement((NS_THUMBS, u'thumbnail')) + thumbnail_elt['uri'] = u'cid:' + thumbnail['id'] + thumbnail_elt['media-type'] = MIME_TYPE + width, height = thumbnail['size'] + thumbnail_elt['width'] = unicode(width) + thumbnail_elt['height'] = unicode(height) + + def _getFileThumbnails(self, file_elt, file_data): + thumbnails = [] + for thumbnail_elt in file_elt.elements(NS_THUMBS, u'thumbnail'): + uri = thumbnail_elt['uri'] + if uri.startswith ('cid:'): + thumbnail = {'id': uri[4:]} + width = thumbnail_elt.getAttribute('width') + height = thumbnail_elt.getAttribute('height') + if width and height: + try: + thumbnail['size'] = int(width), int(height) + except ValueError: + pass + try: + thumbnail['mime_type'] = thumbnail_elt['media-type'] + except KeyError: + pass + thumbnails.append(thumbnail) + + if thumbnails: + file_data.setdefault('extra', {})[C.KEY_THUMBNAILS] = thumbnails + + ## thumbnails generation ## + + def getThumbId(self, image_uid, size): + """return an ID unique for image/size combination + + @param image_uid(unicode): unique id of the image + can be a hash + @param size(tuple(int)): requested size of thumbnail + @return (unicode): unique id for this image/size + """ + return hashlib.sha256(repr((image_uid, size))).hexdigest() + + def _blockingGenThumb(self, source_path, size=None, max_age=None, image_uid=None): + """Generate a thumbnail for image + + This is a blocking method and must be executed in a thread + params are the same as for [generateThumbnail] + """ + if size is None: + size = self.SIZE_SMALL + try: + img = Image.open(source_path) + except IOError: + return Failure(exceptions.DataError(u"Can't open image")) + + img.thumbnail(size) + uid = self.getThumbId(image_uid or source_path, size) + + with self.host.common_cache.cacheData( + PLUGIN_INFO[C.PI_IMPORT_NAME], + uid, + MIME_TYPE, + max_age, + ) as f: + img.save(f, SAVE_FORMAT) + + return img.size, uid + + def generateThumbnail(self, source_path, size=None, max_age=None, image_uid=None): + """Generate a thumbnail of image + + @param source_path(unicode): absolute path to source image + @param size(int, None): max size of the thumbnail + can be one of self.SIZE_* + None to use default value (i.e. self.SIZE_SMALL) + @param max_age(int, None): same as for [memory.cache.Cache.cacheData]) + @param image_uid(unicode, None): unique ID to identify the image + use hash whenever possible + if None, source_path will be used + @return D(tuple[tuple[int,int], unicode]): tuple with: + - size of the thumbnail + - unique Id of the thumbnail + """ + + d = threads.deferToThread( + self._blockingGenThumb, source_path, size, max_age, image_uid=image_uid) + d.addErrback(lambda failure_: + log.error(u"thumbnail generation error: {}".format(failure_))) + return d + + +class XEP_0264_handler(XMPPHandler): + implements(iwokkel.IDisco) + + def getDiscoInfo(self, requestor, target, nodeIdentifier=''): + return [disco.DiscoFeature(NS_THUMBS)] + + def getDiscoItems(self, requestor, target, nodeIdentifier=''): + return []