[bug] delay couch state initialization

The couch state checks if all user databases have the correct schema
version on initialization, and may log errors and raise exceptions if
that is not the case. Because we are currently using `twistd web
--wsgi`, if those errors are logged too early the reactor may have not
been started and the twistd logging facilities may not have been
initialized.

This commit delays the state initialization until the reactor has been
started, to make sure any errors raised and logged in that stage will
actually reach the logfile.

2 files changed, 42 insertions, 12 deletions

diff --git a/server/src/leap/soledad/server/application.py b/server/src/leap/soledad/server/application.py
index a9ebcaf6..17296425 100644
--- a/server/src/leap/soledad/server/application.py
+++ b/server/src/leap/soledad/server/application.py
@@ -1,6 +1,6 @@
 # -*- coding: utf-8 -*-
 # application.py
-# Copyright (C) 2013 LEAP
+# Copyright (C) 2016 LEAP
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -14,6 +14,14 @@
 #
 # You should have received a copy of the GNU General Public License
 # along with this program. If not, see <http://www.gnu.org/licenses/>.
+"""
+A WSGI application to serve as the root resource of the webserver.
+
+Use it like this:
+
+  twistd web --wsgi=leap.soledad.server.application.wsgi_application
+"""
+from twisted.internet import reactor
 
 from leap.soledad.server import SoledadApp
 from leap.soledad.server.auth import SoledadTokenAuthMiddleware
@@ -21,11 +29,11 @@ from leap.soledad.server.gzip_middleware import GzipMiddleware
 from leap.soledad.server.config import load_configuration
 from leap.soledad.common.backend import SoledadBackend
 from leap.soledad.common.couch.state import CouchServerState
+from leap.soledad.common.log import getLogger
 
 
-# ----------------------------------------------------------------------------
-# Run as Twisted WSGI Resource
-# ----------------------------------------------------------------------------
+__all__ = ['wsgi_application']
+
 
 def _load_config():
     conf = load_configuration('/etc/soledad/soledad-server.conf')
@@ -40,8 +48,26 @@ def _get_couch_state():
     return state
 
 
-_couch_state = _get_couch_state()
+_app = SoledadTokenAuthMiddleware(SoledadApp(None))  # delay state init
+wsgi_application = GzipMiddleware(_app)
+
+
+# During its initialization, the couch state verifies if all user databases
+# contain a config document with the correct couch schema version stored, and
+# will log an error and raise an exception if that is not the case.
+#
+# If this verification made too early (i.e.  before the reactor has started and
+# the twistd web logging facilities have been setup), the logging will not
+# work.  Because of that, we delay couch state initialization until the reactor
+# is running.
+
+def _init_couch_state(_app):
+    try:
+        _app.state = _get_couch_state()
+    except Exception as e:
+        logger = getLogger()
+        logger.error(str(e))
+        reactor.stop()
+
 
-# a WSGI application that may be used by `twistd -web`
-wsgi_application = GzipMiddleware(
-    SoledadTokenAuthMiddleware(SoledadApp(_couch_state)))
+reactor.callWhenRunning(_init_couch_state, _app)
diff --git a/server/src/leap/soledad/server/auth.py b/server/src/leap/soledad/server/auth.py
index b7186b3b..b0764569 100644
--- a/server/src/leap/soledad/server/auth.py
+++ b/server/src/leap/soledad/server/auth.py
@@ -343,9 +343,13 @@ class SoledadTokenAuthMiddleware(SoledadAuthMiddleware):
 
     TOKEN_AUTH_ERROR_STRING = "Incorrect address or token."
 
-    def __init__(self, app):
-        self._state = app.state
-        super(SoledadTokenAuthMiddleware, self).__init__(app)
+    def _get_state(self):
+        return self._app.state
+
+    def _set_state(self, state):
+        self._app.state = state
+
+    state = property(_get_state, _set_state)
 
     def _verify_authentication_scheme(self, scheme):
         """
@@ -379,7 +383,7 @@ class SoledadTokenAuthMiddleware(SoledadAuthMiddleware):
         """
         token = auth_data  # we expect a cleartext token at this point
         try:
-            return self._state.verify_token(uuid, token)
+            return self.state.verify_token(uuid, token)
         except Exception as e:
             logger.error(e)
             return False