view sat/plugins/plugin_xep_0264.py @ 3728:b15644cae50d

component AP gateway: JID/node ⟺ AP outbox conversion: - convert a combination of JID and optional pubsub node to AP actor handle (see `getJIDAndNode` for details) and vice versa - the gateway now provides a Pubsub service - retrieve pubsub node and convert it to AP collection, AP pagination is converted to RSM - do the opposite: convert AP collection to pubsub and handle RSM request. Due to ActivityStream collection pagination limitations, some RSM request produce inefficient requests, but caching should be used most of the time in the future and avoid the problem. - set specific name to HTTP Server - new `local_only` setting (`True` by default) to indicate if the gateway can request or not XMPP Pubsub nodes from other servers - disco info now specifies important features such as Pubsub RSM, and nodes metadata ticket 363
author Goffi <goffi@goffi.org>
date Tue, 25 Jan 2022 17:54:06 +0100
parents 2dab494e56fc
children 524856bd7b19
line wrap: on
line source

#!/usr/bin/env python3

# SàT plugin for managing xep-0264
# Copyright (C) 2009-2021 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 implementer

from wokkel import disco, iwokkel

from sat.core import exceptions
import hashlib

try:
    from PIL import Image, ImageOps
except:
    raise exceptions.MissingModule(
        "Missing module pillow, please download/install it from https://python-pillow.github.io"
    )

#  cf. https://stackoverflow.com/a/23575424
from PIL import ImageFile

ImageFile.LOAD_TRUNCATED_IMAGES = True

try:
    from twisted.words.protocols.xmlstream import XMPPHandler
except ImportError:
    from wokkel.subprotocols import XMPPHandler


MIME_TYPE = "image/jpeg"
SAVE_FORMAT = "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 = (320, 320)
    SIZE_MEDIUM = (640, 640)
    SIZE_BIG = (1280, 1280)
    SIZE_FULL_SCREEN = (2560, 2560)
    # FIXME: SIZE_FULL_SCREEN is currently discarded as the resulting files are too big
    # for BoB
    # TODO: use an other mechanism than BoB for bigger files
    SIZES = (SIZE_SMALL, SIZE_MEDIUM, SIZE_BIG)

    def __init__(self, host):
        log.info(_("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, client, file_elt, extra_args):
        try:
            thumbnails = extra_args["extra"][C.KEY_THUMBNAILS]
        except KeyError:
            return
        for thumbnail in thumbnails:
            thumbnail_elt = file_elt.addElement((NS_THUMBS, "thumbnail"))
            thumbnail_elt["uri"] = "cid:" + thumbnail["id"]
            thumbnail_elt["media-type"] = MIME_TYPE
            width, height = thumbnail["size"]
            thumbnail_elt["width"] = str(width)
            thumbnail_elt["height"] = str(height)
        return True

    def _getFileThumbnails(self, client, file_elt, file_data):
        thumbnails = []
        for thumbnail_elt in file_elt.elements(NS_THUMBS, "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:
            # we want thumbnails ordered from smallest to biggest
            thumbnails.sort(key=lambda t: t.get('size', (0, 0)))
            file_data.setdefault("extra", {})[C.KEY_THUMBNAILS] = thumbnails
        return True

    ## 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)).encode()).hexdigest()

    def _blockingGenThumb(
            self, source_path, size=None, max_age=None, image_uid=None,
            fix_orientation=True):
        """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("Can't open image"))

        img.thumbnail(size)
        if fix_orientation:
            img = ImageOps.exif_transpose(img)

        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)
            if fix_orientation:
                log.debug(f"fixed orientation for {f.name}")

        return img.size, uid

    def generateThumbnail(
        self, source_path, size=None, max_age=None, image_uid=None, fix_orientation=True):
        """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
        @param fix_orientation(bool): if True, fix orientation using EXIF data
        @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,
            fix_orientation=fix_orientation
        )
        d.addErrback(
            lambda failure_: log.error("thumbnail generation error: {}".format(failure_))
        )
        return d


@implementer(iwokkel.IDisco)
class XEP_0264_handler(XMPPHandler):

    def getDiscoInfo(self, requestor, target, nodeIdentifier=""):
        return [disco.DiscoFeature(NS_THUMBS)]

    def getDiscoItems(self, requestor, target, nodeIdentifier=""):
        return []