--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libervia/server/session_iface.py	Sat Aug 25 17:59:48 2018 +0200
@@ -0,0 +1,192 @@
+#!/usr/bin/python
+# -*- coding: utf-8 -*-
+
+# Libervia: a SAT frontend
+# 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 zope.interface import Interface, Attribute, implements
+from sat.tools.common import data_objects
+from libervia.server.constants import Const as C
+from collections import OrderedDict
+import os.path
+import shortuuid
+import time
+
+FLAGS_KEY = "_flags"
+MAX_CACHE_AFFILIATIONS = 100  # number of nodes to keep in cache
+
+
+class ISATSession(Interface):
+    profile = Attribute("Sat profile")
+    jid = Attribute("JID associated with the profile")
+    uuid = Attribute("uuid associated with the profile session")
+    identities = Attribute("Identities of XMPP entities")
+
+
+class SATSession(object):
+    implements(ISATSession)
+
+    def __init__(self, session):
+        self.profile = None
+        self.jid = None
+        self.started = time.time()
+        # time when the backend session was started
+        self.backend_started = None
+        self.uuid = unicode(shortuuid.uuid())
+        self.identities = data_objects.Identities()
+        self.csrf_token = unicode(shortuuid.uuid())
+        self.pages_data = {}  # used to keep data accross reloads (key is page instance)
+        self.affiliations = OrderedDict()  # cache for node affiliations
+
+    @property
+    def cache_dir(self):
+        if self.profile is None:
+            return self.service_cache_url + u"/"
+        return os.path.join(u"/", C.CACHE_DIR, self.uuid) + u"/"
+
+    @property
+    def connected(self):
+        return self.profile is not None
+
+    @property
+    def guest(self):
+        """True if this is a guest session"""
+        if self.profile is None:
+            return False
+        else:
+            return self.profile.startswith("guest@@")
+
+    def getPageData(self, page, key):
+        """get session data for a page
+
+        @param page(LiberviaPage): instance of the page
+        @param key(object): data key
+        return (None, object): value of the key
+            None if not found or page_data doesn't exist
+        """
+        return self.pages_data.get(page, {}).get(key)
+
+    def popPageData(self, page, key, default=None):
+        """like getPageData, but remove key once value is gotten
+
+        @param page(LiberviaPage): instance of the page
+        @param key(object): data key
+        @param default(object): value to return if key is not found
+        @return (object): found value or default
+        """
+        page_data = self.pages_data.get(page)
+        if page_data is None:
+            return default
+        value = page_data.pop(key, default)
+        if not page_data:
+            # no need to keep unused page_data
+            del self.pages_data[page]
+        return value
+
+    def setPageData(self, page, key, value):
+        """set data to persist on reload
+
+        @param page(LiberviaPage): instance of the page
+        @param key(object): data key
+        @param value(object): value to set
+        @return (object): set value
+        """
+        page_data = self.pages_data.setdefault(page, {})
+        page_data[key] = value
+        return value
+
+    def setPageFlag(self, page, flag):
+        """set a flag for this page
+
+        @param page(LiberviaPage): instance of the page
+        @param flag(unicode): flag to set
+        """
+        flags = self.getPageData(page, FLAGS_KEY)
+        if flags is None:
+            flags = self.setPageData(page, FLAGS_KEY, set())
+        flags.add(flag)
+
+    def popPageFlag(self, page, flag):
+        """return True if flag is set
+
+        flag is removed if it was set
+        @param page(LiberviaPage): instance of the page
+        @param flag(unicode): flag to set
+        @return (bool): True if flaag was set
+        """
+        page_data = self.pages_data.get(page, {})
+        flags = page_data.get(FLAGS_KEY)
+        if flags is None:
+            return False
+        if flag in flags:
+            flags.remove(flag)
+            # we remove data if they are not used anymore
+            if not flags:
+                del page_data[FLAGS_KEY]
+            if not page_data:
+                del self.pages_data[page]
+            return True
+        else:
+            return False
+
+    def getAffiliation(self, service, node):
+        """retrieve affiliation for a pubsub node
+
+        @param service(jid.JID): pubsub service
+        @param node(unicode): pubsub node
+        @return (unicode, None): affiliation, or None if it is not in cache
+        """
+        if service.resource:
+            raise ValueError(u"Service must not have a resource")
+        if not node:
+            raise ValueError(u"node must be set")
+        try:
+            affiliation = self.affiliations.pop((service, node))
+        except KeyError:
+            return None
+        else:
+            # we replace at the top to get the most recently used on top
+            # so less recently used will be removed if cache is full
+            self.affiliations[(service, node)] = affiliation
+            return affiliation
+
+    def setAffiliation(self, service, node, affiliation):
+        """cache affiliation for a node
+
+        will empty cache when it become too big
+        @param service(jid.JID): pubsub service
+        @param node(unicode): pubsub node
+        @param affiliation(unicode): affiliation to this node
+        """
+        if service.resource:
+            raise ValueError(u"Service must not have a resource")
+        if not node:
+            raise ValueError(u"node must be set")
+        self.affiliations[(service, node)] = affiliation
+        while len(self.affiliations) > MAX_CACHE_AFFILIATIONS:
+            self.affiliations.popitem(last=False)
+
+
+class ISATGuestSession(Interface):
+    id = Attribute("UUID of the guest")
+    data = Attribute("data associated with the guest")
+
+
+class SATGuestSession(object):
+    implements(ISATGuestSession)
+
+    def __init__(self, session):
+        self.id = None
+        self.data = None