Merge branch 'release-v0.99.0' into develop

6 files changed, 103 insertions, 13 deletions

diff --git a/CHANGES.md b/CHANGES.md
index e08b8771b8..458bbaf118 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,3 +1,24 @@
+Synapse 0.99.0rc3 (2019-01-31)
+==============================
+
+Bugfixes
+--------
+
+- Fix infinite loop when an event is redacted in a v3 room ([\#4535](https://github.com/matrix-org/synapse/issues/4535))
+
+
+Improved Documentation
+----------------------
+
+- Update debian installation instructions ([\#4526](https://github.com/matrix-org/synapse/issues/4526))
+
+
+Internal Changes
+----------------
+
+- Add some debug for membership syncing issues ([\#4538](https://github.com/matrix-org/synapse/issues/4538))
+
+
 Synapse 0.99.0rc2 (2019-01-30)
 ==============================
 
diff --git a/README.rst b/README.rst
index 05a3bb3751..e6354ccba0 100644
--- a/README.rst
+++ b/README.rst
@@ -333,12 +333,38 @@ https://developer.github.com/changes/2014-04-25-user-content-security for more d
 Platform-Specific Instructions
 ==============================
 
-Debian
-------
+Debian/Ubuntu
+-------------
+
+Matrix.org packages
+~~~~~~~~~~~~~~~~~~~
+
+Matrix.org provides Debian/Ubuntu packages of the latest stable version of
+Synapse via https://matrix.org/packages/debian/. To use them::
+
+    sudo apt install -y lsb-release curl apt-transport-https
+    echo "deb https://matrix.org/packages/debian `lsb_release -cs` main" |
+        sudo tee /etc/apt/sources.list.d/matrix-org.list
+    curl "https://matrix.org/packages/debian/repo-key.asc" |
+        sudo apt-key add -
+    sudo apt update
+    sudo apt install matrix-synapse-py3
+
+Downstream Debian/Ubuntu packages
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+For ``buster`` and ``sid``, Synapse is available in the Debian repositories and
+it should be possible to install it with simply::
+
+    sudo apt install matrix-synapse
+
+There is also a version of ``matrix-synapse`` in ``stretch-backports``. Please
+see the `Debian documentation on backports
+<https://backports.debian.org/Instructions/>`_ for information on how to use
+them.
 
-Matrix provides official Debian packages via apt from https://matrix.org/packages/debian/.
-Note that these packages do not include a client - choose one from
-https://matrix.org/docs/projects/try-matrix-now.html (or build your own with one of our SDKs :)
+We do not recommend using the packages in downstream Ubuntu at this time, as
+they are old and suffer from known security vulnerabilities.
 
 Fedora
 ------
diff --git a/contrib/prometheus/README b/contrib/prometheus/README.md
index 7b733172e6..e646cb7ea7 100644
--- a/contrib/prometheus/README
+++ b/contrib/prometheus/README.md
@@ -6,8 +6,10 @@ To use it, first install prometheus by following the instructions at
   http://prometheus.io/
 
 ### for Prometheus v1
+
 Add a new job to the main prometheus.conf file:
 
+```yaml
   job: {
     name: "synapse"
 
@@ -15,10 +17,12 @@ Add a new job to the main prometheus.conf file:
       target: "http://SERVER.LOCATION.HERE:PORT/_synapse/metrics"
     }
   }
+```
 
 ### for Prometheus v2
 Add a new job to the main prometheus.yml file:
 
+```yaml
   - job_name: "synapse"
     metrics_path: "/_synapse/metrics"
     # when endpoint uses https:
@@ -26,11 +30,14 @@ Add a new job to the main prometheus.yml file:
 
     static_configs:
     - targets: ['SERVER.LOCATION:PORT']
+```
 
 To use `synapse.rules` add
 
+```yaml
     rule_files:
       - "/PATH/TO/synapse-v2.rules"
+```
 
 Metrics are disabled by default when running synapse; they must be enabled
 with the 'enable-metrics' option, either in the synapse config file or as a
diff --git a/synapse/__init__.py b/synapse/__init__.py
index 5da59aa924..e5f680bb31 100644
--- a/synapse/__init__.py
+++ b/synapse/__init__.py
@@ -27,4 +27,4 @@ try:
 except ImportError:
     pass
 
-__version__ = "0.99.0rc2"
+__version__ = "0.99.0rc3"
diff --git a/synapse/handlers/sync.py b/synapse/handlers/sync.py
index 28857bfc1c..bd97241ab4 100644
--- a/synapse/handlers/sync.py
+++ b/synapse/handlers/sync.py
@@ -895,14 +895,17 @@ class SyncHandler(object):
         Returns:
             Deferred(SyncResult)
         """
-        logger.info("Calculating sync response for %r", sync_config.user)
-
         # NB: The now_token gets changed by some of the generate_sync_* methods,
         # this is due to some of the underlying streams not supporting the ability
         # to query up to a given point.
         # Always use the `now_token` in `SyncResultBuilder`
         now_token = yield self.event_sources.get_current_token()
 
+        logger.info(
+            "Calculating sync response for %r between %s and %s",
+            sync_config.user, since_token, now_token,
+        )
+
         user_id = sync_config.user.to_string()
         app_service = self.store.get_app_service_by_user_id(user_id)
         if app_service:
@@ -1390,6 +1393,12 @@ class SyncHandler(object):
         room_entries = []
         invited = []
         for room_id, events in iteritems(mem_change_events_by_room_id):
+            logger.info(
+                "Membership changes in %s: [%s]",
+                room_id,
+                ", ".join(("%s (%s)" % (e.event_id, e.membership) for e in events)),
+            )
+
             non_joins = [e for e in events if e.membership != Membership.JOIN]
             has_join = len(non_joins) != len(events)
 
diff --git a/synapse/storage/events_worker.py b/synapse/storage/events_worker.py
index 57dae324c7..1716be529a 100644
--- a/synapse/storage/events_worker.py
+++ b/synapse/storage/events_worker.py
@@ -161,6 +161,12 @@ class EventsWorkerStore(SQLBaseStore):
             log_ctx = LoggingContext.current_context()
             log_ctx.record_event_fetch(len(missing_events_ids))
 
+            # Note that _enqueue_events is also responsible for turning db rows
+            # into FrozenEvents (via _get_event_from_row), which involves seeing if
+            # the events have been redacted, and if so pulling the redaction event out
+            # of the database to check it.
+            #
+            # _enqueue_events is a bit of a rubbish name but naming is hard.
             missing_events = yield self._enqueue_events(
                 missing_events_ids,
                 allow_rejected=allow_rejected,
@@ -179,14 +185,35 @@ class EventsWorkerStore(SQLBaseStore):
             # instead.
             if not allow_rejected and entry.event.type == EventTypes.Redaction:
                 if entry.event.internal_metadata.need_to_check_redaction():
-                    orig = yield self.get_event(
-                        entry.event.redacts,
+                    # XXX: we need to avoid calling get_event here.
+                    #
+                    # The problem is that we end up at this point when an event
+                    # which has been redacted is pulled out of the database by
+                    # _enqueue_events, because _enqueue_events needs to check the
+                    # redaction before it can cache the redacted event. So obviously,
+                    # calling get_event to get the redacted event out of the database
+                    # gives us an infinite loop.
+                    #
+                    # For now (quick hack to fix during 0.99 release cycle), we just
+                    # go and fetch the relevant row from the db, but it would be nice
+                    # to think about how we can cache this rather than hit the db
+                    # every time we access a redaction event.
+                    #
+                    # One thought on how to do this:
+                    #  1. split _get_events up so that it is divided into (a) get the
+                    #     rawish event from the db/cache, (b) do the redaction/rejection
+                    #     filtering
+                    #  2. have _get_event_from_row just call the first half of that
+
+                    orig_sender = yield self._simple_select_one_onecol(
+                        table="events",
+                        keyvalues={"event_id": entry.event.redacts},
+                        retcol="sender",
                         allow_none=True,
-                        allow_rejected=True,
-                        get_prev_content=False,
                     )
+
                     expected_domain = get_domain_from_id(entry.event.sender)
-                    if orig and get_domain_from_id(orig.sender) == expected_domain:
+                    if orig_sender and get_domain_from_id(orig_sender) == expected_domain:
                         # This redaction event is allowed. Mark as not needing a
                         # recheck.
                         entry.event.internal_metadata.recheck_redaction = False