diff options
Diffstat (limited to 'common')
5 files changed, 115 insertions, 406 deletions
| diff --git a/common/src/leap/soledad/common/couch.py b/common/src/leap/soledad/common/couch.py index 1c762036..38041c09 100644 --- a/common/src/leap/soledad/common/couch.py +++ b/common/src/leap/soledad/common/couch.py @@ -26,13 +26,12 @@ import logging  import binascii  import time  import sys -import threading  from StringIO import StringIO -from collections import defaultdict  from urlparse import urljoin  from contextlib import contextmanager +from multiprocessing.pool import ThreadPool  from couchdb.client import Server, Database @@ -103,6 +102,7 @@ class CouchDocument(SoledadDocument):          SoledadDocument.__init__(self, doc_id, rev, json, has_conflicts)          self.couch_rev = None          self.transactions = None +        self._conflicts = None      def get_conflicts(self):          """ @@ -111,7 +111,7 @@ class CouchDocument(SoledadDocument):          :return: The conflicted versions of the document.          :rtype: [CouchDocument]          """ -        return self._conflicts +        return self._conflicts or []      def set_conflicts(self, conflicts):          """ @@ -357,61 +357,19 @@ def couch_server(url):      :type url: str      """      session = Session(timeout=COUCH_TIMEOUT) -    server = Server(url=url, session=session) +    server = Server(url=url, full_commit=False, session=session)      yield server +THREAD_POOL = ThreadPool(20) + +  class CouchDatabase(CommonBackend):      """      A U1DB implementation that uses CouchDB as its persistence layer.      """ -    # We spawn threads to parallelize the CouchDatabase.get_docs() method -    MAX_GET_DOCS_THREADS = 20 - -    update_handler_lock = defaultdict(threading.Lock) -    sync_info_lock = defaultdict(threading.Lock) - -    class _GetDocThread(threading.Thread): - -        """ -        A thread that gets a document from a database. - -        TODO: switch this for a twisted deferred to thread. This depends on -        replacing python-couchdb for paisley in this module. -        """ - -        def __init__(self, db, doc_id, check_for_conflicts, -                     release_fun): -            """ -            :param db: The database from where to get the document. -            :type db: CouchDatabase -            :param doc_id: The doc_id of the document to be retrieved. -            :type doc_id: str -            :param check_for_conflicts: Whether the get_doc() method should -                                        check for existing conflicts. -            :type check_for_conflicts: bool -            :param release_fun: A function that releases a semaphore, to be -                                called after the document is fetched. -            :type release_fun: function -            """ -            threading.Thread.__init__(self) -            self._db = db -            self._doc_id = doc_id -            self._check_for_conflicts = check_for_conflicts -            self._release_fun = release_fun -            self._doc = None - -        def run(self): -            """ -            Fetch the document, store it as a property, and call the release -            function. -            """ -            self._doc = self._db._get_doc( -                self._doc_id, self._check_for_conflicts) -            self._release_fun() -      @classmethod      def open_database(cls, url, create, replica_uid=None, ensure_ddocs=False):          """ @@ -476,9 +434,23 @@ class CouchDatabase(CommonBackend):              self._set_replica_uid(replica_uid)          if ensure_ddocs:              self.ensure_ddocs_on_db() -        # initialize a thread pool for parallelizing get_docs() -        self._sem_pool = threading.BoundedSemaphore( -            value=self.MAX_GET_DOCS_THREADS) +        self._cache = None + +    @property +    def cache(self): +        if self._cache is not None: +            return self._cache +        else: +            return {} + +    def init_caching(self, cache): +        """ +        Start using cache by setting internal _cache attribute. + +        :param cache: the cache instance, anything that behaves like a dict +        :type cache: dict +        """ +        self._cache = cache      def ensure_ddocs_on_db(self):          """ @@ -557,10 +529,14 @@ class CouchDatabase(CommonBackend):          :rtype: str          """          if self._real_replica_uid is not None: +            self.cache[self._url] = {'replica_uid': self._real_replica_uid}              return self._real_replica_uid +        if self._url in self.cache: +            return self.cache[self._url]['replica_uid']          try:              # grab replica_uid from server              doc = self._database['u1db_config'] +            self.cache[self._url] = doc              self._real_replica_uid = doc['replica_uid']              return self._real_replica_uid          except ResourceNotFound: @@ -595,10 +571,13 @@ class CouchDatabase(CommonBackend):                                               unknown reason.          """          # query a couch list function +        if self.replica_uid + '_gen' in self.cache: +            return self.cache[self.replica_uid + '_gen']['generation']          ddoc_path = ['_design', 'transactions', '_list', 'generation', 'log']          res = self._database.resource(*ddoc_path)          try:              response = res.get_json() +            self.cache[self.replica_uid + '_gen'] = response[2]              return response[2]['generation']          except ResourceNotFound as e:              raise_missing_design_doc_error(e, ddoc_path) @@ -626,11 +605,15 @@ class CouchDatabase(CommonBackend):                                               design document for an yet                                               unknown reason.          """ +        if self.replica_uid + '_gen' in self.cache: +            response = self.cache[self.replica_uid + '_gen'] +            return (response['generation'], response['transaction_id'])          # query a couch list function          ddoc_path = ['_design', 'transactions', '_list', 'generation', 'log']          res = self._database.resource(*ddoc_path)          try:              response = res.get_json() +            self.cache[self.replica_uid + '_gen'] = response[2]              return (response[2]['generation'], response[2]['transaction_id'])          except ResourceNotFound as e:              raise_missing_design_doc_error(e, ddoc_path) @@ -734,6 +717,10 @@ class CouchDatabase(CommonBackend):                      attachments=True)[2]          except ResourceNotFound:              return None +        return self.__parse_doc_from_couch(result, doc_id, check_for_conflicts) + +    def __parse_doc_from_couch(self, result, doc_id, +                               check_for_conflicts=False):          # restrict to u1db documents          if 'u1db_rev' not in result:              return None @@ -798,11 +785,8 @@ class CouchDatabase(CommonBackend):          """          generation = self._get_generation() -        results = [] -        for row in self._database.view('_all_docs'): -            doc = self.get_doc(row.id, include_deleted=include_deleted) -            if doc is not None: -                results.append(doc) +        results = list(self.get_docs(self._database, +                                     include_deleted=include_deleted))          return (generation, results)      def _put_doc(self, old_doc, doc): @@ -890,6 +874,10 @@ class CouchDatabase(CommonBackend):                  doc.doc_id, body=buf.getvalue(), headers=envelope.headers)          except ResourceConflict:              raise RevisionConflict() +        if self.replica_uid + '_gen' in self.cache: +            gen_info = self.cache[self.replica_uid + '_gen'] +            gen_info['generation'] += 1 +            gen_info['transaction_id'] = transactions[-1][1]      def put_doc(self, doc):          """ @@ -1092,14 +1080,22 @@ class CouchDatabase(CommonBackend):                   synchronized with the replica, this is (0, '').          :rtype: (int, str)          """ -        # query a couch view -        result = self._database.view('syncs/log') -        if len(result[other_replica_uid].rows) == 0: -            return (0, '') -        return ( -            result[other_replica_uid].rows[0]['value']['known_generation'], -            result[other_replica_uid].rows[0]['value']['known_transaction_id'] -        ) +        if other_replica_uid in self.cache: +            return self.cache[other_replica_uid] + +        doc_id = 'u1db_sync_%s' % other_replica_uid +        try: +            doc = self._database[doc_id] +        except ResourceNotFound: +            doc = { +                '_id': doc_id, +                'generation': 0, +                'transaction_id': '', +            } +            self._database.save(doc) +        result = doc['generation'], doc['transaction_id'] +        self.cache[other_replica_uid] = result +        return result      def _set_replica_gen_and_trans_id(self, other_replica_uid,                                        other_generation, other_transaction_id, @@ -1159,42 +1155,17 @@ class CouchDatabase(CommonBackend):          :type doc_idx: int          :param sync_id: The id of the current sync session.          :type sync_id: str - -        :raise MissingDesignDocError: Raised when tried to access a missing -                                      design document. -        :raise MissingDesignDocListFunctionError: Raised when trying to access -                                                  a missing list function on a -                                                  design document. -        :raise MissingDesignDocNamedViewError: Raised when trying to access a -                                               missing named view on a design -                                               document. -        :raise MissingDesignDocDeletedError: Raised when trying to access a -                                             deleted design document. -        :raise MissingDesignDocUnknownError: Raised when failed to access a -                                             design document for an yet -                                             unknown reason.          """ -        # query a couch update function -        ddoc_path = ['_design', 'syncs', '_update', 'put', 'u1db_sync_log'] -        res = self._database.resource(*ddoc_path) +        self.cache[other_replica_uid] = (other_generation, +                                         other_transaction_id) +        doc_id = 'u1db_sync_%s' % other_replica_uid          try: -            with CouchDatabase.update_handler_lock[self._get_replica_uid()]: -                body = { -                    'other_replica_uid': other_replica_uid, -                    'other_generation': other_generation, -                    'other_transaction_id': other_transaction_id, -                } -                if number_of_docs is not None: -                    body['number_of_docs'] = number_of_docs -                if doc_idx is not None: -                    body['doc_idx'] = doc_idx -                if sync_id is not None: -                    body['sync_id'] = sync_id -                res.put_json( -                    body=body, -                    headers={'content-type': 'application/json'}) -        except ResourceNotFound as e: -            raise_missing_design_doc_error(e, ddoc_path) +            doc = self._database[doc_id] +        except ResourceNotFound: +            doc = {'_id': doc_id} +        doc['generation'] = other_generation +        doc['transaction_id'] = other_transaction_id +        self._database.save(doc)      def _force_doc_sync_conflict(self, doc):          """ @@ -1203,10 +1174,11 @@ class CouchDatabase(CommonBackend):          :param doc: The document to be put.          :type doc: CouchDocument          """ -        my_doc = self._get_doc(doc.doc_id, check_for_conflicts=True) -        doc.prune_conflicts( -            vectorclock.VectorClockRev(doc.rev), self._replica_uid) -        doc.add_conflict(my_doc) +        my_doc = self._get_doc(doc.doc_id) +        self._prune_conflicts(doc, vectorclock.VectorClockRev(doc.rev)) +        doc.add_conflict(self._factory(doc.doc_id, my_doc.rev, +                                       my_doc.get_json())) +        doc.has_conflicts = True          self._put_doc(my_doc, doc)      def resolve_doc(self, doc, conflicted_doc_revs): @@ -1320,42 +1292,27 @@ class CouchDatabase(CommonBackend):          """          if not isinstance(doc, CouchDocument):              doc = self._factory(doc.doc_id, doc.rev, doc.get_json()) -        self._save_source_info(replica_uid, replica_gen, -                               replica_trans_id, number_of_docs, -                               doc_idx, sync_id)          my_doc = self._get_doc(doc.doc_id, check_for_conflicts=True) -        if my_doc is not None: -            my_doc.set_conflicts( -                self.get_doc_conflicts(my_doc.doc_id, my_doc.couch_rev)) -        state, save_doc = _process_incoming_doc( -            my_doc, doc, save_conflict, self.replica_uid) -        if save_doc: -            self._put_doc(my_doc, save_doc) -            doc.update(save_doc) -        return state, self._get_generation() - -    def _save_source_info(self, replica_uid, replica_gen, replica_trans_id, -                          number_of_docs, doc_idx, sync_id): -        """ -        Validate and save source information. -        """ -        self._validate_source(replica_uid, replica_gen, replica_trans_id) -        self._set_replica_gen_and_trans_id( -            replica_uid, replica_gen, replica_trans_id, -            number_of_docs=number_of_docs, doc_idx=doc_idx, -            sync_id=sync_id) +        if my_doc: +            doc.set_conflicts(my_doc.get_conflicts()) +        return CommonBackend._put_doc_if_newer(self, doc, save_conflict, +                                               replica_uid, replica_gen, +                                               replica_trans_id) + +    def _put_and_update_indexes(self, cur_doc, doc): +        self._put_doc(cur_doc, doc)      def get_docs(self, doc_ids, check_for_conflicts=True,                   include_deleted=False):          """          Get the JSON content for many documents. -        :param doc_ids: A list of document identifiers. +        :param doc_ids: A list of document identifiers or None for all.          :type doc_ids: list          :param check_for_conflicts: If set to False, then the conflict check                                      will be skipped, and 'None' will be                                      returned instead of True/False. -        :type check_for_conflictsa: bool +        :type check_for_conflicts: bool          :param include_deleted: If set to True, deleted documents will be                                  returned with empty content. Otherwise deleted                                  documents will not be included in the results. @@ -1363,31 +1320,14 @@ class CouchDatabase(CommonBackend):                   in matching doc_ids order.          :rtype: iterable          """ -        # Workaround for: -        # -        #   http://bugs.python.org/issue7980 -        #   https://leap.se/code/issues/5449 -        # -        # python-couchdb uses time.strptime, which is not thread safe. In -        # order to avoid the problem described on the issues above, we preload -        # strptime here by evaluating the conversion of an arbitrary date. -        # This will not be needed when/if we switch from python-couchdb to -        # paisley. -        time.strptime('Mar 8 1917', '%b %d %Y') -        # spawn threads to retrieve docs -        threads = [] -        for doc_id in doc_ids: -            self._sem_pool.acquire() -            t = self._GetDocThread(self, doc_id, check_for_conflicts, -                                   self._sem_pool.release) -            t.start() -            threads.append(t) -        # join threads and yield docs -        for t in threads: -            t.join() -            if t._doc.is_tombstone() and not include_deleted: +        get_one = lambda doc_id: self._get_doc(doc_id, check_for_conflicts) +        docs = [THREAD_POOL.apply_async(get_one, [doc_id]) +                for doc_id in doc_ids] +        for doc in docs: +            doc = doc.get() +            if not doc or not include_deleted and doc.is_tombstone():                  continue -            yield t._doc +            yield doc      def _prune_conflicts(self, doc, doc_vcr):          """ @@ -1459,10 +1399,11 @@ class CouchServerState(ServerState):          :return: The CouchDatabase object.          :rtype: CouchDatabase          """ -        return CouchDatabase( +        db = CouchDatabase(              self.couch_url,              dbname,              ensure_ddocs=False) +        return db      def ensure_database(self, dbname):          """ @@ -1494,53 +1435,3 @@ class CouchServerState(ServerState):                               delete databases.          """          raise Unauthorized() - - -def _process_incoming_doc(my_doc, other_doc, save_conflict, replica_uid): -    """ -    Check document, save and return state. -    """ -    # at this point, `doc` has arrived from the other syncing party, and -    # we will decide what to do with it. -    # First, we prepare the arriving doc to update couch database. -    new_doc = CouchDocument( -        other_doc.doc_id, other_doc.rev, other_doc.get_json()) -    if my_doc is None: -        return 'inserted', new_doc -    new_doc.couch_rev = my_doc.couch_rev -    new_doc.set_conflicts(my_doc.get_conflicts()) -    # fetch conflicts because we will eventually manipulate them -    # from now on, it works just like u1db sqlite backend -    doc_vcr = vectorclock.VectorClockRev(new_doc.rev) -    cur_vcr = vectorclock.VectorClockRev(my_doc.rev) -    if doc_vcr.is_newer(cur_vcr): -        rev = new_doc.rev -        new_doc.prune_conflicts(doc_vcr, replica_uid) -        if new_doc.rev != rev: -            # conflicts have been autoresolved -            return 'superseded', new_doc -        else: -            return'inserted', new_doc -    elif new_doc.rev == my_doc.rev: -        # magical convergence -        return 'converged', None -    elif cur_vcr.is_newer(doc_vcr): -        # Don't add this to seen_ids, because we have something newer, -        # so we should send it back, and we should not generate a -        # conflict -        other_doc.update(new_doc) -        return 'superseded', None -    elif my_doc.same_content_as(new_doc): -        # the documents have been edited to the same thing at both ends -        doc_vcr.maximize(cur_vcr) -        doc_vcr.increment(replica_uid) -        new_doc.rev = doc_vcr.as_str() -        return 'superseded', new_doc -    else: -        if save_conflict: -            new_doc.prune_conflicts( -                vectorclock.VectorClockRev(new_doc.rev), replica_uid) -            new_doc.add_conflict(my_doc) -            return 'conflicted', new_doc -        other_doc.update(new_doc) -        return 'conflicted', None diff --git a/common/src/leap/soledad/common/ddocs/syncs/updates/put.js b/common/src/leap/soledad/common/ddocs/syncs/updates/put.js deleted file mode 100644 index b0ae2de6..00000000 --- a/common/src/leap/soledad/common/ddocs/syncs/updates/put.js +++ /dev/null @@ -1,151 +0,0 @@ -/** - * The u1db_sync_log document stores both the actual sync log and a list of - * pending updates to the log, in case we receive incoming documents out of - * the correct order (i.e. if there are parallel PUTs during the sync - * process). - * - * The structure of the document is the following: - * - *     { - *         'syncs': [ - *             ['<replica_uid>', <gen>, '<trans_id>'], - *             ...  - *         ], - *         'pending': { - *             'other_replica_uid': { - *                 'sync_id': '<sync_id>', - *                 'log': [[<gen>, '<trans_id>'], ...] - *             }, - *             ... - *         } - *     } - * - * The update function below does the following: - * - *   0. If we do not receive a sync_id, we just update the 'syncs' list with - *      the incoming info about the source replica state. - * - *   1. Otherwise, if the incoming sync_id differs from current stored - *      sync_id, then we assume that the previous sync session for that source - *      replica was interrupted and discard all pending data. - * - *   2. Then we append incoming info as pending data for that source replica - *      and current sync_id, and sort the pending data by generation. - * - *   3. Then we go through pending data and find the most recent generation - *      that we can use to update the actual sync log. - * - *   4. Finally, we insert the most up to date information into the sync log. - */ -function(doc, req){ - -    // create the document if it doesn't exist -    if (!doc) { -        doc = {} -        doc['_id'] = 'u1db_sync_log'; -        doc['syncs'] = []; -    } - -    // get and validate incoming info -    var body = JSON.parse(req.body); -    var other_replica_uid = body['other_replica_uid']; -    var other_generation = parseInt(body['other_generation']); -    var other_transaction_id = body['other_transaction_id'] -    var sync_id = body['sync_id']; -    var number_of_docs = body['number_of_docs']; -    var doc_idx = body['doc_idx']; - -    // parse integers -    if (number_of_docs != null) -        number_of_docs = parseInt(number_of_docs); -    if (doc_idx != null) -        doc_idx = parseInt(doc_idx); - -    if (other_replica_uid == null -            || other_generation == null -            || other_transaction_id == null) -        return [null, 'invalid data']; - -    // create slot for pending logs -    if (doc['pending'] == null) -        doc['pending'] = {}; - -    // these are the values that will be actually inserted -    var current_gen = other_generation; -    var current_trans_id = other_transaction_id; - -    /*------------- Wait for sequential values before storing -------------*/ - -    // we just try to obtain pending log if we received a sync_id -    if (sync_id != null) { - -        // create slot for current source and sync_id pending log -        if (doc['pending'][other_replica_uid] == null -                || doc['pending'][other_replica_uid]['sync_id'] != sync_id) { -            doc['pending'][other_replica_uid] = { -                'sync_id': sync_id, -                'log': [], -                'last_doc_idx': 0, -            } -        } - -        // append incoming data to pending log -        doc['pending'][other_replica_uid]['log'].push([ -            other_generation, -            other_transaction_id, -            doc_idx, -        ]) - -        // sort pending log according to generation -        doc['pending'][other_replica_uid]['log'].sort(function(a, b) { -            return a[0] - b[0]; -        }); - -        // get most up-to-date information from pending log -        var last_doc_idx = doc['pending'][other_replica_uid]['last_doc_idx']; -        var pending_idx = doc['pending'][other_replica_uid]['log'][0][2]; - -        current_gen = null; -        current_trans_id = null; - -        while (last_doc_idx + 1 == pending_idx) { -            pending = doc['pending'][other_replica_uid]['log'].shift() -            current_gen = pending[0]; -            current_trans_id = pending[1]; -            last_doc_idx = pending[2] -            if (doc['pending'][other_replica_uid]['log'].length == 0) -                break; -            pending_idx = doc['pending'][other_replica_uid]['log'][0][2]; -        } - -        // leave the sync log untouched if we still did not receive enough docs -        if (current_gen == null) -            return [doc, 'ok']; - -        // update last index of received doc -        doc['pending'][other_replica_uid]['last_doc_idx'] = last_doc_idx; - -        // eventually remove all pending data from that replica -        if (last_doc_idx == number_of_docs) -            delete doc['pending'][other_replica_uid] -    } - -    /*--------------- Store source replica info on sync log ---------------*/ - -    // remove outdated info -    doc['syncs'] = doc['syncs'].filter( -        function (entry) { -            return entry[0] != other_replica_uid; -        } -    ); - -    // store in log -    doc['syncs'].push([ -        other_replica_uid, -        current_gen, -        current_trans_id  -    ]); - -    return [doc, 'ok']; -} - diff --git a/common/src/leap/soledad/common/ddocs/syncs/views/log/map.js b/common/src/leap/soledad/common/ddocs/syncs/views/log/map.js deleted file mode 100644 index a63c7cf4..00000000 --- a/common/src/leap/soledad/common/ddocs/syncs/views/log/map.js +++ /dev/null @@ -1,12 +0,0 @@ -function(doc) { -    if (doc._id == 'u1db_sync_log') { -        if (doc.syncs) -            doc.syncs.forEach(function (entry) { -                emit(entry[0], -                    { -                        'known_generation': entry[1], -                        'known_transaction_id': entry[2] -                    }); -            }); -    } -} diff --git a/common/src/leap/soledad/common/tests/test_couch.py b/common/src/leap/soledad/common/tests/test_couch.py index a08ffd16..c8d13667 100644 --- a/common/src/leap/soledad/common/tests/test_couch.py +++ b/common/src/leap/soledad/common/tests/test_couch.py @@ -1359,10 +1359,6 @@ class CouchDatabaseExceptionsTests(CouchDBTestCase):          self.assertRaises(              errors.MissingDesignDocError,              self.db.whats_changed) -        # _do_set_replica_gen_and_trans_id() -        self.assertRaises( -            errors.MissingDesignDocError, -            self.db._do_set_replica_gen_and_trans_id, 1, 2, 3)      def test_missing_design_doc_functions_raises(self):          """ @@ -1489,10 +1485,6 @@ class CouchDatabaseExceptionsTests(CouchDBTestCase):          self.assertRaises(              errors.MissingDesignDocDeletedError,              self.db.whats_changed) -        # _do_set_replica_gen_and_trans_id() -        self.assertRaises( -            errors.MissingDesignDocDeletedError, -            self.db._do_set_replica_gen_and_trans_id, 1, 2, 3)      def test_ensure_ddoc_independently(self):          """ diff --git a/common/src/leap/soledad/common/tests/test_couch_operations_atomicity.py b/common/src/leap/soledad/common/tests/test_couch_operations_atomicity.py index 25f709ca..3e8e8cce 100644 --- a/common/src/leap/soledad/common/tests/test_couch_operations_atomicity.py +++ b/common/src/leap/soledad/common/tests/test_couch_operations_atomicity.py @@ -163,6 +163,7 @@ class CouchAtomicityTestCase(CouchDBTestCase, TestCaseWithServer):                  2,                  len(filter(lambda t: t[0] == doc_id, transaction_log))) +    @defer.inlineCallbacks      def test_correct_sync_log_after_sequential_syncs(self):          """          Assert that the sync_log increases accordingly with sequential syncs. @@ -170,21 +171,21 @@ class CouchAtomicityTestCase(CouchDBTestCase, TestCaseWithServer):          sol = self._soledad_instance(              auth_token='auth-token',              server_url=self.getURL()) +        source_replica_uid = sol._dbpool.replica_uid -        def _create_docs(results): +        def _create_docs():              deferreds = []              for i in xrange(0, REPEAT_TIMES):                  deferreds.append(sol.create_doc({})) -            return defer.DeferredList(deferreds) +            return defer.gatherResults(deferreds)          def _assert_transaction_and_sync_logs(results, sync_idx):              # assert sizes of transaction and sync logs              self.assertEqual(                  sync_idx * REPEAT_TIMES,                  len(self.db._get_transaction_log())) -            self.assertEqual( -                1 if sync_idx > 0 else 0, -                len(self.db._database.view('syncs/log').rows)) +            gen, _ = self.db._get_replica_gen_and_trans_id(source_replica_uid) +            self.assertEqual(sync_idx * REPEAT_TIMES, gen)          def _assert_sync(results, sync_idx):              gen, docs = results @@ -193,40 +194,28 @@ class CouchAtomicityTestCase(CouchDBTestCase, TestCaseWithServer):              # assert sizes of transaction and sync logs              self.assertEqual((sync_idx + 1) * REPEAT_TIMES,                               len(self.db._get_transaction_log())) -            sync_log_rows = self.db._database.view('syncs/log').rows -            sync_log = sync_log_rows[0].value -            replica_uid = sync_log_rows[0].key -            known_gen = sync_log['known_generation'] -            known_trans_id = sync_log['known_transaction_id'] -            # assert sync_log has exactly 1 row -            self.assertEqual(1, len(sync_log_rows)) -            # assert it has the correct replica_uid, gen and trans_id -            self.assertEqual(sol._dbpool.replica_uid, replica_uid) +            target_known_gen, target_known_trans_id = \ +                self.db._get_replica_gen_and_trans_id(source_replica_uid) +            # assert it has the correct gen and trans_id              conn_key = sol._dbpool._u1dbconnections.keys().pop()              conn = sol._dbpool._u1dbconnections[conn_key]              sol_gen, sol_trans_id = conn._get_generation_info() -            self.assertEqual(sol_gen, known_gen) -            self.assertEqual(sol_trans_id, known_trans_id) - -        # create some documents -        d = _create_docs(None) +            self.assertEqual(sol_gen, target_known_gen) +            self.assertEqual(sol_trans_id, target_known_trans_id)          # sync first time and assert success -        d.addCallback(_assert_transaction_and_sync_logs, 0) -        d.addCallback(lambda _: sol.sync()) -        d.addCallback(lambda _: sol.get_all_docs()) -        d.addCallback(_assert_sync, 0) +        results = yield _create_docs() +        _assert_transaction_and_sync_logs(results, 0) +        yield sol.sync() +        results = yield sol.get_all_docs() +        _assert_sync(results, 0)          # create more docs, sync second time and assert success -        d.addCallback(_create_docs) -        d.addCallback(_assert_transaction_and_sync_logs, 1) -        d.addCallback(lambda _: sol.sync()) -        d.addCallback(lambda _: sol.get_all_docs()) -        d.addCallback(_assert_sync, 1) - -        d.addCallback(lambda _: sol.close()) - -        return d +        results = yield _create_docs() +        _assert_transaction_and_sync_logs(results, 1) +        yield sol.sync() +        results = yield sol.get_all_docs() +        _assert_sync(results, 1)      #      # Concurrency tests | 
