[pkg] unify client and server into a single python package

We have been discussing about this merge for a while.
Its main goal is to simplify things: code navigation, but also
packaging.

The rationale is that the code is more cohesive in this way, and there's
only one source package to install.

Dependencies that are only for the server or the client will not be
installed by default, and they are expected to be provided by the
environment. There are setuptools extras defined for the client and the
server.

Debianization is still expected to split the single source package into
3 binaries.

Another avantage is that the documentation can now install a single
package with a single step, and therefore include the docstrings into
the generated docs.

- Resolves: #8896

1 files changed, 231 insertions, 0 deletions

diff --git a/src/leap/soledad/client/sync.py b/src/leap/soledad/client/sync.py
new file mode 100644
index 00000000..2a927189
--- /dev/null
+++ b/src/leap/soledad/client/sync.py
@@ -0,0 +1,231 @@
+# -*- coding: utf-8 -*-
+# sync.py
+# Copyright (C) 2014 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/>.
+"""
+Soledad synchronization utilities.
+"""
+import os
+
+from twisted.internet import defer
+
+from leap.soledad.common.log import getLogger
+from leap.soledad.common.l2db import errors
+from leap.soledad.common.l2db.sync import Synchronizer
+from leap.soledad.common.errors import BackendNotReadyError
+
+
+logger = getLogger(__name__)
+
+
+# we may want to collect statistics from the sync process
+DO_STATS = False
+if os.environ.get('SOLEDAD_STATS'):
+    DO_STATS = True
+
+
+class SoledadSynchronizer(Synchronizer):
+    """
+    Collect the state around synchronizing 2 U1DB replicas.
+
+    Synchronization is bi-directional, in that new items in the source are sent
+    to the target, and new items in the target are returned to the source.
+    However, it still recognizes that one side is initiating the request. Also,
+    at the moment, conflicts are only created in the source.
+
+    Also modified to allow for interrupting the synchronization process.
+    """
+    received_docs = []
+
+    def __init__(self, *args, **kwargs):
+        Synchronizer.__init__(self, *args, **kwargs)
+        if DO_STATS:
+            self.sync_phase = [0]
+            self.sync_exchange_phase = None
+
+    @defer.inlineCallbacks
+    def sync(self):
+        """
+        Synchronize documents between source and target.
+
+        :return: A deferred which will fire after the sync has finished with
+                 the local generation before the synchronization was performed.
+        :rtype: twisted.internet.defer.Deferred
+        """
+
+        sync_target = self.sync_target
+        self.received_docs = []
+
+        # ---------- phase 1: get sync info from server ----------------------
+        if DO_STATS:
+            self.sync_phase[0] += 1
+            self.sync_exchange_phase = self.sync_target.sync_exchange_phase
+        # --------------------------------------------------------------------
+
+        # get target identifier, its current generation,
+        # and its last-seen database generation for this source
+        ensure_callback = None
+        try:
+            (self.target_replica_uid, target_gen, target_trans_id,
+             target_my_gen, target_my_trans_id) = yield \
+                sync_target.get_sync_info(self.source._replica_uid)
+        except (errors.DatabaseDoesNotExist, BackendNotReadyError) as e:
+            logger.warn("Database isn't ready on server. Will be created.")
+            logger.warn("Reason: %s" % e.__class__)
+            self.target_replica_uid = None
+            target_gen, target_trans_id = 0, ''
+            target_my_gen, target_my_trans_id = 0, ''
+
+        logger.debug("target replica uid: %s" % self.target_replica_uid)
+        logger.debug("target generation: %d" % target_gen)
+        logger.debug("target trans id: %s" % target_trans_id)
+        logger.debug("target my gen: %d" % target_my_gen)
+        logger.debug("target my trans_id: %s" % target_my_trans_id)
+        logger.debug("source replica_uid: %s" % self.source._replica_uid)
+
+        # make sure we'll have access to target replica uid once it exists
+        if self.target_replica_uid is None:
+
+            def ensure_callback(replica_uid):
+                self.target_replica_uid = replica_uid
+
+        # make sure we're not syncing one replica with itself
+        if self.target_replica_uid == self.source._replica_uid:
+            raise errors.InvalidReplicaUID
+
+        # validate the info the target has about the source replica
+        self.source.validate_gen_and_trans_id(
+            target_my_gen, target_my_trans_id)
+
+        # ---------- phase 2: what's changed ---------------------------------
+        if DO_STATS:
+            self.sync_phase[0] += 1
+        # --------------------------------------------------------------------
+
+        # what's changed since that generation and this current gen
+        my_gen, _, changes = self.source.whats_changed(target_my_gen)
+        logger.debug("there are %d documents to send" % len(changes))
+
+        # get source last-seen database generation for the target
+        if self.target_replica_uid is None:
+            target_last_known_gen, target_last_known_trans_id = 0, ''
+        else:
+            target_last_known_gen, target_last_known_trans_id = \
+                self.source._get_replica_gen_and_trans_id(
+                    self.target_replica_uid)
+            logger.debug(
+                "last known target gen: %d" % target_last_known_gen)
+            logger.debug(
+                "last known target trans_id: %s" % target_last_known_trans_id)
+
+        # validate transaction ids
+        if not changes and target_last_known_gen == target_gen:
+            if target_trans_id != target_last_known_trans_id:
+                raise errors.InvalidTransactionId
+            defer.returnValue(my_gen)
+
+        # ---------- phase 3: sync exchange ----------------------------------
+        if DO_STATS:
+            self.sync_phase[0] += 1
+        # --------------------------------------------------------------------
+
+        docs_by_generation = self._docs_by_gen_from_changes(changes)
+
+        # exchange documents and try to insert the returned ones with
+        # the target, return target synced-up-to gen.
+        new_gen, new_trans_id = yield sync_target.sync_exchange(
+            docs_by_generation, self.source._replica_uid,
+            target_last_known_gen, target_last_known_trans_id,
+            self._insert_doc_from_target, ensure_callback=ensure_callback)
+        ids_sent = [doc_id for doc_id, _, _ in changes]
+        logger.debug("target gen after sync: %d" % new_gen)
+        logger.debug("target trans_id after sync: %s" % new_trans_id)
+        if hasattr(self.source, 'commit'):  # sqlcipher backend speed up
+            self.source.commit()  # insert it all in a single transaction
+        info = {
+            "target_replica_uid": self.target_replica_uid,
+            "new_gen": new_gen,
+            "new_trans_id": new_trans_id,
+            "my_gen": my_gen
+        }
+        self._syncing_info = info
+
+        # ---------- phase 4: complete sync ----------------------------------
+        if DO_STATS:
+            self.sync_phase[0] += 1
+        # --------------------------------------------------------------------
+
+        yield self.complete_sync()
+
+        _, _, changes = self.source.whats_changed(target_my_gen)
+        changed_doc_ids = [doc_id for doc_id, _, _ in changes]
+
+        just_received = list(set(changed_doc_ids) - set(ids_sent))
+        self.received_docs = just_received
+
+        # ---------- phase 5: sync is over -----------------------------------
+        if DO_STATS:
+            self.sync_phase[0] += 1
+        # --------------------------------------------------------------------
+
+        defer.returnValue(my_gen)
+
+    def _docs_by_gen_from_changes(self, changes):
+        docs_by_generation = []
+        kwargs = {'include_deleted': True}
+        for doc_id, gen, trans in changes:
+            get_doc = (self.source.get_doc, (doc_id,), kwargs)
+            docs_by_generation.append((get_doc, gen, trans))
+        return docs_by_generation
+
+    def complete_sync(self):
+        """
+        Last stage of the synchronization:
+            (a) record last known generation and transaction uid for the remote
+            replica, and
+            (b) make target aware of our current reached generation.
+
+        :return: A deferred which will fire when the sync has been completed.
+        :rtype: twisted.internet.defer.Deferred
+        """
+        logger.debug("completing deferred last step in sync...")
+
+        # record target synced-up-to generation including applying what we
+        # sent
+        info = self._syncing_info
+        self.source._set_replica_gen_and_trans_id(
+            info["target_replica_uid"], info["new_gen"], info["new_trans_id"])
+
+        # if gapless record current reached generation with target
+        return self._record_sync_info_with_the_target(info["my_gen"])
+
+    def _record_sync_info_with_the_target(self, start_generation):
+        """
+        Store local replica metadata in server.
+
+        :param start_generation: The local generation when the sync was
+                                 started.
+        :type start_generation: int
+
+        :return: A deferred which will fire when the operation has been
+                 completed.
+        :rtype: twisted.internet.defer.Deferred
+        """
+        cur_gen, trans_id = self.source._get_generation_info()
+        if (cur_gen == start_generation + self.num_inserted and
+                self.num_inserted > 0):
+            return self.sync_target.record_sync_info(
+                self.source._replica_uid, cur_gen, trans_id)
+        return defer.succeed(None)