1 files changed, 123 insertions, 0 deletions
diff --git a/src/leap/soledad/common/couch/check.py b/src/leap/soledad/common/couch/check.py
new file mode 100644
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+++ b/src/leap/soledad/common/couch/check.py
@@ -0,0 +1,123 @@
+# -*- coding: utf-8 -*-
+# check.py
+# Copyright (C) 2015,2016 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
+# 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 General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
+"""
+Database schema version verification
+"""
+
+import os
+import treq
+
+from six.moves.urllib.parse import urljoin
+from twisted.internet import defer
+from urlparse import urlsplit
+
+from twisted.internet import reactor
+
+from leap.soledad.common.couch import CONFIG_DOC_ID
+from leap.soledad.common.couch import SCHEMA_VERSION
+from leap.soledad.common.couch import SCHEMA_VERSION_KEY
+from leap.soledad.common.errors import WrongCouchSchemaVersionError
+from leap.soledad.common.errors import MissingCouchConfigDocumentError
+from leap.soledad.common.log import getLogger
+
+
+logger = getLogger(__name__)
+
+
+@defer.inlineCallbacks
+def _check_db_schema_version(url, db, auth, agent=None):
+    """
+    Check if the schema version is up to date for a given database.
+
+    :param url: the server base URL.
+    :type url: str
+    :param db: the database name.
+    :type db: str
+    :param auth: a tuple with (username, password) for acessing CouchDB.
+    :type auth: tuple(str, str)
+    :param agent: an optional agent for doing requests, used in tests.
+    :type agent: twisted.web.client.Agent
+
+    :raise MissingCouchConfigDocumentError: raised when a database is not empty
+                                            but has no config document in it.
+
+    :raise WrongCouchSchemaVersionError: raised when a config document was
+                                         found but the schema version is
+                                         different from what is expected.
+    """
+    # if there are documents, ensure that a config doc exists
+    db_url = urljoin(url, '%s/' % db)
+    config_doc_url = urljoin(db_url, CONFIG_DOC_ID)
+    res = yield treq.get(config_doc_url, auth=auth, agent=agent)
+
+    if res.code != 200 and res.code != 404:
+        raise Exception("Unexpected HTTP response code: %d" % res.code)
+
+    elif res.code == 404:
+        res = yield treq.get(urljoin(db_url, '_all_docs'), auth=auth,
+                             params={'limit': 1}, agent=agent)
+        docs = yield res.json()
+        if docs['total_rows'] != 0:
+            logger.error(
+                "Missing couch config document in database %s" % db)
+            raise MissingCouchConfigDocumentError(db)
+
+    elif res.code == 200:
+        config_doc = yield res.json()
+        if config_doc[SCHEMA_VERSION_KEY] != SCHEMA_VERSION:
+            logger.error(
+                "Unsupported database schema in database %s" % db)
+            raise WrongCouchSchemaVersionError(db)
+
+
+def _stop(failure, reactor):
+    logger.error("Failure while checking schema versions: %r - %s"
+                 % (failure, failure.message))
+    reactor.addSystemEventTrigger('after', 'shutdown', os._exit, 1)
+    reactor.stop()
+
+
+@defer.inlineCallbacks
+def check_schema_versions(couch_url, agent=None, reactor=reactor):
+    """
+    Check that all user databases use the correct couch schema.
+
+    :param couch_url: The URL for the couch database.
+    :type couch_url: str
+    :param agent: an optional agent for doing requests, used in tests.
+    :type agent: twisted.web.client.Agent
+    :param reactor: an optional reactor for stopping in case of errors, used
+                    in tests.
+    :type reactor: twisted.internet.base.ReactorBase
+    """
+    url = urlsplit(couch_url)
+    auth = (url.username, url.password) if url.username else None
+    url = "%s://%s:%d" % (url.scheme, url.hostname, url.port)
+    res = yield treq.get(urljoin(url, '_all_dbs'), auth=auth, agent=agent)
+    dbs = yield res.json()
+    deferreds = []
+    semaphore = defer.DeferredSemaphore(20)
+    logger.info('Starting schema versions check...')
+    for db in dbs:
+        if not db.startswith('user-'):
+            continue
+        d = semaphore.run(_check_db_schema_version, url, db, auth, agent=agent)
+        d.addErrback(_stop, reactor=reactor)
+        deferreds.append(d)
+    d = defer.gatherResults(deferreds, consumeErrors=True)
+    d.addCallback(lambda _: logger.info('Finished schema versions check.'))
+    yield d