--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/sat/plugins/plugin_comp_file_sharing.py	Mon Apr 02 19:44:50 2018 +0200
@@ -0,0 +1,382 @@
+#!/usr/bin/env python2
+# -*- coding: utf-8 -*-
+
+# SAT plugin for parrot mode (experimental)
+# Copyright (C) 2009-2018 Jérôme Poisson (goffi@goffi.org)
+
+# 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 import exceptions
+from sat.core.log import getLogger
+log = getLogger(__name__)
+from sat.tools.common import regex
+from sat.tools.common import uri
+from sat.tools import stream
+from twisted.internet import defer
+from twisted.words.protocols.jabber import error
+from wokkel import pubsub
+from wokkel import generic
+from functools import partial
+import os
+import os.path
+import mimetypes
+
+
+PLUGIN_INFO = {
+    C.PI_NAME: "File sharing component",
+    C.PI_IMPORT_NAME: "file_sharing",
+    C.PI_MODES: [C.PLUG_MODE_COMPONENT],
+    C.PI_TYPE: C.PLUG_TYPE_ENTRY_POINT,
+    C.PI_PROTOCOLS: [],
+    C.PI_DEPENDENCIES: ["FILE", "XEP-0231", "XEP-0234", "XEP-0260", "XEP-0261", "XEP-0264", "XEP-0329"],
+    C.PI_RECOMMENDATIONS: [],
+    C.PI_MAIN: "FileSharing",
+    C.PI_HANDLER: C.BOOL_TRUE,
+    C.PI_DESCRIPTION: _(u"""Component hosting and sharing files""")
+}
+
+HASH_ALGO = u'sha-256'
+NS_COMMENTS = 'org.salut-a-toi.comments'
+COMMENT_NODE_PREFIX = 'org.salut-a-toi.file_comments/'
+
+
+class FileSharing(object):
+
+    def __init__(self, host):
+        log.info(_(u"File Sharing initialization"))
+        self.host = host
+        self._f = host.plugins['FILE']
+        self._jf = host.plugins['XEP-0234']
+        self._h = host.plugins['XEP-0300']
+        self._t = host.plugins['XEP-0264']
+        host.trigger.add("FILE_getDestDir", self._getDestDirTrigger)
+        host.trigger.add("XEP-0234_fileSendingRequest", self._fileSendingRequestTrigger, priority=1000)
+        host.trigger.add("XEP-0234_buildFileElement", self._addFileComments)
+        host.trigger.add("XEP-0234_parseFileElement", self._getFileComments)
+        host.trigger.add("XEP-0329_compGetFilesFromNode", self._addCommentsData)
+        self.files_path = host.getLocalPath(None, C.FILES_DIR, profile=False)
+
+    def getHandler(self, client):
+        return Comments_handler(self)
+
+    def profileConnected(self, client):
+        path = client.file_tmp_dir = os.path.join(
+            self.host.memory.getConfig('', 'local_dir'),
+            C.FILES_TMP_DIR,
+            regex.pathEscape(client.profile))
+        if not os.path.exists(path):
+            os.makedirs(path)
+
+    @defer.inlineCallbacks
+    def _fileTransferedCb(self, dummy, client, peer_jid, file_data, file_path):
+        """post file reception tasks
+
+        on file is received, this method create hash/thumbnails if necessary
+        move the file to the right location, and create metadata entry in database
+        """
+        name = file_data[u'name']
+        extra = {}
+
+        if file_data[u'hash_algo'] == HASH_ALGO:
+            log.debug(_(u"Reusing already generated hash"))
+            file_hash = file_data[u'hash_hasher'].hexdigest()
+        else:
+            hasher = self._h.getHasher(HASH_ALGO)
+            with open('file_path') as f:
+                file_hash = yield self._h.calculateHash(f, hasher)
+        final_path = os.path.join(self.files_path, file_hash)
+
+        if os.path.isfile(final_path):
+            log.debug(u"file [{file_hash}] already exists, we can remove temporary one".format(file_hash = file_hash))
+            os.unlink(file_path)
+        else:
+            os.rename(file_path, final_path)
+            log.debug(u"file [{file_hash}] moved to {files_path}".format(file_hash=file_hash, files_path=self.files_path))
+
+        mime_type = file_data.get(u'mime_type')
+        if not mime_type or mime_type == u'application/octet-stream':
+            mime_type = mimetypes.guess_type(name)[0]
+
+        if mime_type is not None and mime_type.startswith(u'image'):
+            thumbnails = extra.setdefault(C.KEY_THUMBNAILS, [])
+            for max_thumb_size in (self._t.SIZE_SMALL, self._t.SIZE_MEDIUM):
+                try:
+                    thumb_size, thumb_id = yield self._t.generateThumbnail(final_path,
+                                                                           max_thumb_size,
+                                                                           # we keep thumbnails for 6 months
+                                                                           60*60*24*31*6)
+                except Exception as e:
+                    log.warning(_(u"Can't create thumbnail: {reason}").format(reason=e))
+                    break
+                thumbnails.append({u'id': thumb_id, u'size': thumb_size})
+
+        self.host.memory.setFile(client,
+                                 name=name,
+                                 version=u'',
+                                 file_hash=file_hash,
+                                 hash_algo=HASH_ALGO,
+                                 size=file_data[u'size'],
+                                 path=file_data.get(u'path'),
+                                 namespace=file_data.get(u'namespace'),
+                                 mime_type=mime_type,
+                                 owner=peer_jid,
+                                 extra=extra)
+
+    def _getDestDirTrigger(self, client, peer_jid, transfer_data, file_data, stream_object):
+        """This trigger accept file sending request, and store file locally"""
+        if not client.is_component:
+            return True, None
+        assert stream_object
+        assert 'stream_object' not in transfer_data
+        assert C.KEY_PROGRESS_ID in file_data
+        filename = file_data['name']
+        assert filename and not '/' in filename
+        file_tmp_dir = self.host.getLocalPath(client, C.FILES_TMP_DIR, peer_jid.userhost(), component=True, profile=False)
+        file_tmp_path = file_data['file_path'] = os.path.join(file_tmp_dir, file_data['name'])
+
+        transfer_data['finished_d'].addCallback(self._fileTransferedCb, client, peer_jid, file_data, file_tmp_path)
+
+        self._f.openFileWrite(client, file_tmp_path, transfer_data, file_data, stream_object)
+        return False, defer.succeed(True)
+
+    @defer.inlineCallbacks
+    def _retrieveFiles(self, client, session, content_data, content_name, file_data, file_elt):
+        """This method retrieve a file on request, and send if after checking permissions"""
+        peer_jid = session[u'peer_jid']
+        try:
+            found_files = yield self.host.memory.getFiles(client,
+                                                          peer_jid=peer_jid,
+                                                          name=file_data.get(u'name'),
+                                                          file_hash=file_data.get(u'file_hash'),
+                                                          hash_algo=file_data.get(u'hash_algo'),
+                                                          path=file_data.get(u'path'),
+                                                          namespace=file_data.get(u'namespace'))
+        except exceptions.NotFound:
+            found_files = None
+        except exceptions.PermissionError:
+            log.warning(_(u"{peer_jid} is trying to access an unauthorized file: {name}").format(
+                peer_jid=peer_jid, name=file_data.get(u'name')))
+            defer.returnValue(False)
+
+        if not found_files:
+            log.warning(_(u"no matching file found ({file_data})").format(file_data=file_data))
+            defer.returnValue(False)
+
+        # we only use the first found file
+        found_file = found_files[0]
+        file_hash = found_file[u'file_hash']
+        file_path = os.path.join(self.files_path, file_hash)
+        file_data[u'hash_hasher'] = hasher = self._h.getHasher(found_file[u'hash_algo'])
+        size = file_data[u'size'] = found_file[u'size']
+        file_data[u'file_hash'] = file_hash
+        file_data[u'hash_algo'] = found_file[u'hash_algo']
+
+        # we complete file_elt so peer can have some details on the file
+        if u'name' not in file_data:
+            file_elt.addElement(u'name', content=found_file[u'name'])
+        file_elt.addElement(u'size', content=unicode(size))
+        content_data['stream_object'] = stream.FileStreamObject(
+            self.host,
+            client,
+            file_path,
+            uid=self._jf.getProgressId(session, content_name),
+            size=size,
+            data_cb=lambda data: hasher.update(data),
+            )
+        defer.returnValue(True)
+
+    def _fileSendingRequestTrigger(self, client, session, content_data, content_name, file_data, file_elt):
+        if not client.is_component:
+            return True, None
+        else:
+            return False, self._retrieveFiles(client, session, content_data, content_name, file_data, file_elt)
+
+    ## comments triggers ##
+
+    def _addFileComments(self, file_elt, extra_args):
+        try:
+            comments_url = extra_args.pop('comments_url')
+        except KeyError:
+            return
+
+        comment_elt = file_elt.addElement((NS_COMMENTS, 'comments'), content=comments_url)
+
+        try:
+            count = len(extra_args[u'extra'][u'comments'])
+        except KeyError:
+            count = 0
+
+        comment_elt['count'] = unicode(count)
+        return True
+
+    def _getFileComments(self, file_elt, file_data):
+        try:
+            comments_elt = next(file_elt.elements(NS_COMMENTS, 'comments'))
+        except StopIteration:
+            return
+        file_data['comments_url'] = unicode(comments_elt)
+        file_data['comments_count'] = comments_elt['count']
+        return True
+
+    def _addCommentsData(self, client, iq_elt, owner, node_path, files_data):
+        for file_data in files_data:
+            file_data['comments_url'] = uri.buildXMPPUri('pubsub',
+                                                         path=client.jid.full(),
+                                                         node=COMMENT_NODE_PREFIX + file_data['id'])
+        return True
+
+
+class Comments_handler(pubsub.PubSubService):
+    """This class is a minimal Pubsub service handling virtual nodes for comments"""
+
+    def __init__(self, plugin_parent):
+        super(Comments_handler, self).__init__() # PubsubVirtualResource())
+        self.host = plugin_parent.host
+        self.plugin_parent = plugin_parent
+        self.discoIdentity = {'category': 'pubsub',
+                              'type': 'virtual',  # FIXME: non standard, here to avoid this service being considered as main pubsub one
+                              'name': 'files commenting service'}
+
+    def _getFileId(self, nodeIdentifier):
+        if not nodeIdentifier.startswith(COMMENT_NODE_PREFIX):
+            raise error.StanzaError('item-not-found')
+        file_id = nodeIdentifier[len(COMMENT_NODE_PREFIX):]
+        if not file_id:
+            raise error.StanzaError('item-not-found')
+        return file_id
+
+    @defer.inlineCallbacks
+    def getFileData(self, requestor, nodeIdentifier):
+        file_id = self._getFileId(nodeIdentifier)
+        try:
+            files = yield self.host.memory.getFiles(self.parent, requestor, file_id)
+        except (exceptions.NotFound, exceptions.PermissionError):
+            # we don't differenciate between NotFound and PermissionError
+            # to avoid leaking information on existing files
+            raise error.StanzaError('item-not-found')
+        if not files:
+            raise error.StanzaError('item-not-found')
+        if len(files) > 1:
+            raise error.InternalError('there should be only one file')
+        defer.returnValue(files[0])
+
+    def commentsUpdate(self, extra, new_comments, peer_jid):
+        """update comments (replace or insert new_comments)
+
+        @param extra(dict): extra data to update
+        @param new_comments(list[tuple(unicode, unicode, unicode)]): comments to update or insert
+        @param peer_jid(unicode, None): bare jid of the requestor, or None if request is done by owner
+        """
+        current_comments = extra.setdefault('comments', [])
+        new_comments_by_id = {c[0]:c for c in new_comments}
+        updated = []
+        # we now check every current comment, to see if one id in new ones
+        # exist, in which case we must update
+        for idx, comment in enumerate(current_comments):
+            comment_id = comment[0]
+            if comment_id in new_comments_by_id:
+                # a new comment has an existing id, update is requested
+                if peer_jid and comment[1] != peer_jid:
+                    # requestor has not the right to modify the comment
+                    raise exceptions.PermissionError
+                # we replace old_comment with updated one
+                new_comment = new_comments_by_id[comment_id]
+                current_comments[idx] = new_comment
+                updated.append(new_comment)
+
+        # we now remove every updated comments, to only keep
+        # the ones to insert
+        for comment in updated:
+            new_comments.remove(comment)
+
+        current_comments.extend(new_comments)
+
+    def commentsDelete(self, extra, comments):
+        try:
+            comments_dict = extra['comments']
+        except KeyError:
+            return
+        for comment in comments:
+            try:
+                comments_dict.remove(comment)
+            except ValueError:
+                continue
+
+    def _getFrom(self, item_elt):
+        """retrieve published of an item
+
+        @param item_elt(domish.element): <item> element
+        @return (unicode): full jid as string
+        """
+        iq_elt = item_elt
+        while iq_elt.parent != None:
+            iq_elt = iq_elt.parent
+        return iq_elt['from']
+
+    @defer.inlineCallbacks
+    def publish(self, requestor, service, nodeIdentifier, items):
+        # we retrieve file a first time to check authorisations
+        file_data = yield self.getFileData(requestor, nodeIdentifier)
+        file_id = file_data['id']
+        comments = [(item['id'], self._getFrom(item), item.toXml()) for item in items]
+        if requestor.userhostJID() == file_data['owner']:
+            peer_jid = None
+        else:
+            peer_jid = requestor.userhost()
+        update_cb = partial(self.commentsUpdate, new_comments=comments, peer_jid=peer_jid)
+        try:
+            yield self.host.memory.fileUpdate(file_id, 'extra', update_cb)
+        except exceptions.PermissionError:
+            raise error.StanzaError('not-authorized')
+
+    @defer.inlineCallbacks
+    def items(self, requestor, service, nodeIdentifier, maxItems,
+                    itemIdentifiers):
+        file_data = yield self.getFileData(requestor, nodeIdentifier)
+        comments = file_data['extra'].get('comments', [])
+        if itemIdentifiers:
+            defer.returnValue([generic.parseXml(c[2]) for c in comments if c[0] in itemIdentifiers])
+        else:
+            defer.returnValue([generic.parseXml(c[2]) for c in comments])
+
+    @defer.inlineCallbacks
+    def retract(self, requestor, service, nodeIdentifier, itemIdentifiers):
+        file_data = yield self.getFileData(requestor, nodeIdentifier)
+        file_id = file_data['id']
+        try:
+            comments = file_data['extra']['comments']
+        except KeyError:
+            raise error.StanzaError('item-not-found')
+
+        to_remove = []
+        for comment in comments:
+            comment_id = comment[0]
+            if comment_id in itemIdentifiers:
+                to_remove.append(comment)
+                itemIdentifiers.remove(comment_id)
+                if not itemIdentifiers:
+                    break
+
+        if itemIdentifiers:
+            # not all items have been to_remove, we can't continue
+            raise error.StanzaError('item-not-found')
+
+        if requestor.userhostJID() != file_data['owner']:
+            if not all([c[1] == requestor.userhost() for c in to_remove]):
+                raise error.StanzaError('not-authorized')
+
+        remove_cb = partial(self.commentsDelete, comments=to_remove)
+        yield self.host.memory.fileUpdate(file_id, 'extra', remove_cb)