Add session_redis

requirements.txt

@@ -1,4 +1,5 @@
 boto==2.42.0
+redis==2.10.5
 python-json-logger==0.1.5
 python-swiftclient==3.4.0
 python-keystoneclient==3.13.0

session_redis/README.rst

@@ -0,0 +1,37 @@
+Sessions in Redis
+=================
+
+This addon allows to store the web sessions in Redis.
+
+Configuration
+-------------
+
+The storage of sessions in Redis is activated using environment variables.
+
+* ``ODOO_SESSION_REDIS`` has to be ``1`` or ``true``
+* ``ODOO_SESSION_REDIS_HOST`` is the redis hostname (default is ``localhost``)
+* ``ODOO_SESSION_REDIS_PORT`` is the redis port (default is ``6379``)
+* ``ODOO_SESSION_REDIS_PASSWORD`` is the password for the AUTH command
+  (optional)
+* ``ODOO_SESSION_REDIS_PREFIX`` is the prefix for the session keys (optional)
+* ``ODOO_SESSION_REDIS_EXPIRATION`` is the time in seconds before expiration of
+  the sessions (default is 7 days)
+
+
+The keys are set to ``session:<session id>``.
+When a prefix is defined, the keys are ``session:<prefix>:<session id>``
+
+This addon must be added in the server wide addons with (``--load`` option):
+
+``--load=web,web_kanban,session_redis``
+
+Limitations
+-----------
+
+* The server has to be restarted in order for the sessions to be stored in
+  Redis.
+* All the users will have to login again as their previous session will be
+  dropped.
+* The addon monkey-patch ``openerp.http.Root.session_store`` with a custom
+  method when the Redis mode is active, so incompatibilities with other addons
+  is possible if they do the same.

session_redis/__init__.py

@@ -0,0 +1,5 @@
+# -*- coding: utf-8 -*-
+
+from . import http
+from . import session
+from . import models

session_redis/__openerp__.py

@@ -0,0 +1,19 @@
+# -*- coding: utf-8 -*-
+# Copyright 2016 Camptocamp SA
+# License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl.html)
+
+
+{'name': 'Sessions in Redis',
+ 'summary': 'Store web sessions in Redis',
+ 'version': '7.0.1.0.0',
+ 'author': 'Camptocamp,Odoo Community Association (OCA)',
+ 'license': 'AGPL-3',
+ 'category': 'Extra Tools',
+ 'depends': ['base'],
+ 'external_dependencies': {
+     'python': ['redis'],
+ },
+ 'website': 'http://www.camptocamp.com',
+ 'data': [],
+ 'installable': True,
+ }

session_redis/http.py

@@ -0,0 +1,92 @@
+# -*- coding: utf-8 -*-
+# Copyright 2016 Camptocamp SA
+# License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl.html)
+
+import logging
+import os
+
+from distutils.util import strtobool
+
+import openerp
+from openerp.addons.web import http
+from werkzeug.contrib.sessions import Session
+
+from .session import RedisSessionStore
+
+_logger = logging.getLogger(__name__)
+
+try:
+    import redis
+    from redis.sentinel import Sentinel
+except ImportError:
+    redis = None  # noqa
+    _logger.debug("Cannot 'import redis'.")
+
+
+def is_true(strval):
+    return bool(strtobool(strval or '0'.lower()))
+
+
+sentinel_host = os.environ.get('ODOO_SESSION_REDIS_SENTINEL_HOST')
+sentinel_master_name = os.environ.get(
+    'ODOO_SESSION_REDIS_SENTINEL_MASTER_NAME'
+)
+if sentinel_host and not sentinel_master_name:
+    raise Exception(
+        "ODOO_SESSION_REDIS_SENTINEL_MASTER_NAME must be defined "
+        "when using session_redis"
+    )
+sentinel_port = int(os.environ.get('ODOO_SESSION_REDIS_SENTINEL_PORT', 26379))
+host = os.environ.get('ODOO_SESSION_REDIS_HOST', 'localhost')
+port = int(os.environ.get('ODOO_SESSION_REDIS_PORT', 6379))
+prefix = os.environ.get('ODOO_SESSION_REDIS_PREFIX')
+password = os.environ.get('ODOO_SESSION_REDIS_PASSWORD')
+expiration = os.environ.get('ODOO_SESSION_REDIS_EXPIRATION')
+
+
+def session_store():
+    if sentinel_host:
+        sentinel = Sentinel([(sentinel_host, sentinel_port)],
+                            password=password)
+        redis_client = sentinel.master_for(sentinel_master_name)
+    else:
+        redis_client = redis.Redis(host=host, port=port, password=password)
+    return RedisSessionStore(redis=redis_client, prefix=prefix,
+                             expiration=expiration,
+                             session_class=Session)
+
+
+def session_gc(session_store):
+    """ Do not garbage collect the sessions
+
+    Redis keys are automatically cleaned at the end of their
+    expiration.
+    """
+    return
+
+
+def purge_fs_sessions(path):
+    for fname in os.listdir(path):
+        path = os.path.join(path, fname)
+        try:
+            os.unlink(path)
+        except OSError:
+            pass
+
+
+if is_true(os.environ.get('ODOO_SESSION_REDIS')):
+    if sentinel_host:
+        _logger.debug("HTTP sessions stored in Redis with prefix '%s'. "
+                      "Using Sentinel on %s:%s",
+                      sentinel_host, sentinel_port, prefix or '')
+    else:
+        _logger.debug("HTTP sessions stored in Redis with prefix '%s' on "
+                      "%s:%s", host, port, prefix or '')
+
+    store = session_store()
+    for handler in openerp.service.wsgi_server.module_handlers:
+        if hasattr(handler, 'session_store'):
+            handler.session_store = store
+    http.session_gc = session_gc
+    # clean the existing sessions on the file system
+    purge_fs_sessions(http.session_path())

session_redis/models/__init__.py

@@ -0,0 +1 @@
+from . import user

session_redis/models/user.py

@@ -0,0 +1,24 @@
+# -*- coding: utf-8 -*-
+# Copyright 2016 Camptocamp SA
+# License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl.html)
+
+from openerp.osv import osv
+from openerp import tools
+
+
+class User(osv.osv):
+    _inherit = 'res.users'
+
+    @tools.ormcache('sid')
+    def _compute_session_token(self, sid):
+        """Make sure to return an unicode string.
+
+        Odoo creates a session token using hexdigest Session which is str
+        but with redis we set the token from a dictionary of values passing
+        it in json format. When dumping values from json, we always get unicode
+        thus both are incompatible.
+
+        The shortest path is to fix the output of the computed session by Odoo.
+
+        """
+        return unicode(super(User, self)._compute_session_token(sid))

session_redis/session.py

@@ -0,0 +1,78 @@
+# -*- coding: utf-8 -*-
+# Copyright 2016 Camptocamp SA
+# License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl.html)
+
+from pickle import dumps, loads, HIGHEST_PROTOCOL
+import logging
+
+from werkzeug.contrib.sessions import SessionStore
+
+# this is equal to the duration of the session garbage collector in
+# openerp.http.session_gc()
+DEFAULT_SESSION_TIMEOUT = 60 * 60 * 24 * 7  # 7 days in seconds
+
+_logger = logging.getLogger(__name__)
+
+
+class RedisSessionStore(SessionStore):
+    """ SessionStore that saves session to redis """
+
+    def __init__(self, redis, session_class=None,
+                 prefix='', expiration=None):
+        super(RedisSessionStore, self).__init__(session_class=session_class)
+        self.redis = redis
+        if expiration is None:
+            self.expiration = DEFAULT_SESSION_TIMEOUT
+        else:
+            self.expiration = expiration
+        self.prefix = u'session:'
+        if prefix:
+            self.prefix = u'%s:%s:' % (
+                self.prefix, prefix
+            )
+
+    def build_key(self, sid):
+        if isinstance(sid, unicode):
+            sid = sid.encode('utf-8')
+        return '%s%s' % (self.prefix, sid)
+
+    def save(self, session):
+        key = self.build_key(session.sid)
+
+        if _logger.isEnabledFor(logging.DEBUG):
+            _logger.debug("saving session with key '%s' and "
+                          "expiration of %s seconds",
+                          key, self.expiration)
+
+        if self.redis.set(key, dumps(dict(session), HIGHEST_PROTOCOL)):
+            return self.redis.expire(key, self.expiration)
+
+    def delete(self, session):
+        key = self.build_key(session.sid)
+        _logger.debug('deleting session with key %s', key)
+        return self.redis.delete(key)
+
+    def get(self, sid):
+        if not self.is_valid_key(sid):
+            _logger.debug("session with invalid sid '%s' has been asked, "
+                          "returning a new one", sid)
+            return self.new()
+
+        key = self.build_key(sid)
+        saved = self.redis.get(key)
+        if not saved:
+            _logger.debug("session with non-existent key '%s' has been asked, "
+                          "returning a new one", key)
+            return self.new()
+        try:
+            data = loads(saved)
+        except ValueError:
+            _logger.debug("session for key '%s' has been asked but its json "
+                          "content could not be read, it has been reset", key)
+            data = {}
+        return self.session_class(data, sid, False)
+
+    def list(self):
+        keys = self.redis.keys('%s*' % self.prefix)
+        _logger.debug("a listing redis keys has been called")
+        return [key[len(self.prefix):] for key in keys]