1a6b718f8c
Pre-populate room data for quick filtering/sorting in the Sliding Sync API Spawning from https://github.com/element-hq/synapse/pull/17450#discussion_r1697335578 This PR is acting as the Synapse version `N+1` step in the gradual migration being tracked by https://github.com/element-hq/synapse/issues/17623 Adding two new database tables: - `sliding_sync_joined_rooms`: A table for storing room meta data that the local server is still participating in. The info here can be shared across all `Membership.JOIN`. Keyed on `(room_id)` and updated when the relevant room current state changes or a new event is sent in the room. - `sliding_sync_membership_snapshots`: A table for storing a snapshot of room meta data at the time of the local user's membership. Keyed on `(room_id, user_id)` and only updated when a user's membership in a room changes. Also adds background updates to populate these tables with all of the existing data. We want to have the guarantee that if a row exists in the sliding sync tables, we are able to rely on it (accurate data). And if a row doesn't exist, we use a fallback to get the same info until the background updates fill in the rows or a new event comes in triggering it to be fully inserted. This means we need a couple extra things in place until we bump `SCHEMA_COMPAT_VERSION` and run the foreground update in the `N+2` part of the gradual migration. For context on why we can't rely on the tables without these things see [1]. 1. On start-up, block until we clear out any rows for the rooms that have had events since the max-`stream_ordering` of the `sliding_sync_joined_rooms` table (compare to max-`stream_ordering` of the `events` table). For `sliding_sync_membership_snapshots`, we can compare to the max-`stream_ordering` of `local_current_membership` - This accounts for when someone downgrades their Synapse version and then upgrades it again. This will ensure that we don't have any stale/out-of-date data in the `sliding_sync_joined_rooms`/`sliding_sync_membership_snapshots` tables since any new events sent in rooms would have also needed to be written to the sliding sync tables. For example a new event needs to bump `event_stream_ordering` in `sliding_sync_joined_rooms` table or some state in the room changing (like the room name). Or another example of someone's membership changing in a room affecting `sliding_sync_membership_snapshots`. 1. Add another background update that will catch-up with any rows that were just deleted from the sliding sync tables (based on the activity in the `events`/`local_current_membership`). The rooms that need recalculating are added to the `sliding_sync_joined_rooms_to_recalculate` table. 1. Making sure rows are fully inserted. Instead of partially inserting, we need to check if the row already exists and fully insert all data if not. All of this extra functionality can be removed once the `SCHEMA_COMPAT_VERSION` is bumped with support for the new sliding sync tables so people can no longer downgrade (the `N+2` part of the gradual migration). <details> <summary><sup>[1]</sup></summary> For `sliding_sync_joined_rooms`, since we partially insert rows as state comes in, we can't rely on the existence of the row for a given `room_id`. We can't even rely on looking at whether the background update has finished. There could still be partial rows from when someone reverted their Synapse version after the background update finished, had some state changes (or new rooms), then upgraded again and more state changes happen leaving a partial row. For `sliding_sync_membership_snapshots`, we insert items as a whole except for the `forgotten` column ~~so we can rely on rows existing and just need to always use a fallback for the `forgotten` data. We can't use the `forgotten` column in the table for the same reasons above about `sliding_sync_joined_rooms`.~~ We could have an out-of-date membership from when someone reverted their Synapse version. (same problems as outlined for `sliding_sync_joined_rooms` above) Discussed in an [internal meeting](https://docs.google.com/document/d/1MnuvPkaCkT_wviSQZ6YKBjiWciCBFMd-7hxyCO-OCbQ/edit#bookmark=id.dz5x6ef4mxz7) </details> ### TODO - [x] Update `stream_ordering`/`bump_stamp` - [x] Handle remote invites - [x] Handle state resets - [x] Consider adding `sender` so we can filter `LEAVE` memberships and distinguish from kicks. - [x] We should add it to be able to tell leaves from kicks - [x] Consider adding `tombstone` state to help address https://github.com/element-hq/synapse/issues/17540 - [x] We should add it `tombstone_successor_room_id` - [x] Consider adding `forgotten` status to avoid extra lookup/table-join on `room_memberships` - [x] We should add it - [x] Background update to fill in values for all joined rooms and non-join membership - [x] Clean-up tables when room is deleted - [ ] Make sure tables are useful to our use case - First explored in https://github.com/element-hq/synapse/compare/erikj/ss_use_new_tables - Also explored in76b5a576eb- [x] Plan for how can we use this with a fallback - See plan discussed above in main area of the issue description - Discussed in an [internal meeting](https://docs.google.com/document/d/1MnuvPkaCkT_wviSQZ6YKBjiWciCBFMd-7hxyCO-OCbQ/edit#bookmark=id.dz5x6ef4mxz7) - [x] Plan for how we can rely on this new table without a fallback - Synapse version `N+1`: (this PR) Bump `SCHEMA_VERSION` to `87`. Add new tables and background update to backfill all rows. Since this is a new table, we don't have to add any `NOT VALID` constraints and validate them when the background update completes. Read from new tables with a fallback in cases where the rows aren't filled in yet. - Synapse version `N+2`: Bump `SCHEMA_VERSION` to `88` and bump `SCHEMA_COMPAT_VERSION` to `87` because we don't want people to downgrade and miss writes while they are on an older version. Add a foreground update to finish off the backfill so we can read from new tables without the fallback. Application code can now rely on the new tables being populated. - Discussed in an [internal meeting](https://docs.google.com/document/d/1MnuvPkaCkT_wviSQZ6YKBjiWciCBFMd-7hxyCO-OCbQ/edit#bookmark=id.hh7shg4cxdhj) ### Dev notes ``` SYNAPSE_TEST_LOG_LEVEL=INFO poetry run trial tests.storage.test_events.SlidingSyncPrePopulatedTablesTestCase SYNAPSE_POSTGRES=1 SYNAPSE_POSTGRES_USER=postgres SYNAPSE_TEST_LOG_LEVEL=INFO poetry run trial tests.storage.test_events.SlidingSyncPrePopulatedTablesTestCase ``` ``` SYNAPSE_TEST_LOG_LEVEL=INFO poetry run trial tests.handlers.test_sliding_sync.FilterRoomsTestCase ``` Reference: - [Development docs on background updates and worked examples of gradual migrations ](1dfa59b238/docs/development/database_schema.md (background-updates)) - A real example of a gradual migration: https://github.com/matrix-org/synapse/pull/15649#discussion_r1213779514 - Adding `rooms.creator` field that needed a background update to backfill data, https://github.com/matrix-org/synapse/pull/10697 - Adding `rooms.room_version` that needed a background update to backfill data, https://github.com/matrix-org/synapse/pull/6729 - Adding `room_stats_state.room_type` that needed a background update to backfill data, https://github.com/matrix-org/synapse/pull/13031 - Tables from MSC2716: `insertion_events`, `insertion_event_edges`, `insertion_event_extremities`, `batch_events` - `current_state_events` updated in `synapse/storage/databases/main/events.py` --- ``` persist_event (adds to queue) _persist_event_batch _persist_events_and_state_updates (assigns `stream_ordering` to events) _persist_events_txn _store_event_txn _update_metadata_tables_txn _store_room_members_txn _update_current_state_txn ``` --- > Concatenated Indexes [...] (also known as multi-column, composite or combined index) > > [...] key consists of multiple columns. > > We can take advantage of the fact that the first index column is always usable for searching > > *-- https://use-the-index-luke.com/sql/where-clause/the-equals-operator/concatenated-keys* --- Dealing with `portdb` (`synapse/_scripts/synapse_port_db.py`), https://github.com/element-hq/synapse/pull/17512#discussion_r1725998219 --- <details> <summary>SQL queries:</summary> Both of these are equivalent and work in SQLite and Postgres Options 1: ```sql WITH data_table (room_id, user_id, membership_event_id, membership, event_stream_ordering, {", ".join(insert_keys)}) AS ( VALUES ( ?, ?, ?, (SELECT membership FROM room_memberships WHERE event_id = ?), (SELECT stream_ordering FROM events WHERE event_id = ?), {", ".join("?" for _ in insert_values)} ) ) INSERT INTO sliding_sync_non_join_memberships (room_id, user_id, membership_event_id, membership, event_stream_ordering, {", ".join(insert_keys)}) SELECT * FROM data_table WHERE membership != ? ON CONFLICT (room_id, user_id) DO UPDATE SET membership_event_id = EXCLUDED.membership_event_id, membership = EXCLUDED.membership, event_stream_ordering = EXCLUDED.event_stream_ordering, {", ".join(f"{key} = EXCLUDED.{key}" for key in insert_keys)} ``` Option 2: ```sql INSERT INTO sliding_sync_non_join_memberships (room_id, user_id, membership_event_id, membership, event_stream_ordering, {", ".join(insert_keys)}) SELECT column1 as room_id, column2 as user_id, column3 as membership_event_id, column4 as membership, column5 as event_stream_ordering, {", ".join("column" + str(i) for i in range(6, 6 + len(insert_keys)))} FROM ( VALUES ( ?, ?, ?, (SELECT membership FROM room_memberships WHERE event_id = ?), (SELECT stream_ordering FROM events WHERE event_id = ?), {", ".join("?" for _ in insert_values)} ) ) as v WHERE membership != ? ON CONFLICT (room_id, user_id) DO UPDATE SET membership_event_id = EXCLUDED.membership_event_id, membership = EXCLUDED.membership, event_stream_ordering = EXCLUDED.event_stream_ordering, {", ".join(f"{key} = EXCLUDED.{key}" for key in insert_keys)} ``` If we don't need the `membership` condition, we could use: ```sql INSERT INTO sliding_sync_non_join_memberships (room_id, membership_event_id, user_id, membership, event_stream_ordering, {", ".join(insert_keys)}) VALUES ( ?, ?, ?, (SELECT membership FROM room_memberships WHERE event_id = ?), (SELECT stream_ordering FROM events WHERE event_id = ?), {", ".join("?" for _ in insert_values)} ) ON CONFLICT (room_id, user_id) DO UPDATE SET membership_event_id = EXCLUDED.membership_event_id, membership = EXCLUDED.membership, event_stream_ordering = EXCLUDED.event_stream_ordering, {", ".join(f"{key} = EXCLUDED.{key}" for key in insert_keys)} ``` </details> ### Pull Request Checklist <!-- Please read https://element-hq.github.io/synapse/latest/development/contributing_guide.html before submitting your pull request --> * [x] Pull request is based on the develop branch * [x] Pull request includes a [changelog file](https://element-hq.github.io/synapse/latest/development/contributing_guide.html#changelog). The entry should: - Be a short description of your change which makes sense to users. "Fixed a bug that prevented receiving messages from other servers." instead of "Moved X method from `EventStore` to `EventWorkerStore`.". - Use markdown where necessary, mostly for `code blocks`. - End with either a period (.) or an exclamation mark (!). - Start with a capital letter. - Feel free to credit yourself, by adding a sentence "Contributed by @github_username." or "Contributed by [Your Name]." to the end of the entry. * [x] [Code style](https://element-hq.github.io/synapse/latest/code_style.html) is correct (run the [linters](https://element-hq.github.io/synapse/latest/development/contributing_guide.html#run-the-linters)) --------- Co-authored-by: Erik Johnston <erik@matrix.org>
.. image:: ./docs/element_logo_white_bg.svg
:height: 60px
**Element Synapse - Matrix homeserver implementation**
|support| |development| |documentation| |license| |pypi| |python|
Synapse is an open source `Matrix <https://matrix.org>`__ homeserver
implementation, written and maintained by `Element <https://element.io>`_.
`Matrix <https://github.com/matrix-org>`__ is the open standard for
secure and interoperable real time communications. You can directly run
and manage the source code in this repository, available under an AGPL
license. There is no support provided from Element unless you have a
subscription.
Subscription alternative
========================
Alternatively, for those that need an enterprise-ready solution, Element
Server Suite (ESS) is `available as a subscription <https://element.io/pricing>`_.
ESS builds on Synapse to offer a complete Matrix-based backend including the full
`Admin Console product <https://element.io/enterprise-functionality/admin-console>`_,
giving admins the power to easily manage an organization-wide
deployment. It includes advanced identity management, auditing,
moderation and data retention options as well as Long Term Support and
SLAs. ESS can be used to support any Matrix-based frontend client.
.. contents::
🛠️ Installing and configuration
===============================
The Synapse documentation describes `how to install Synapse <https://element-hq.github.io/synapse/latest/setup/installation.html>`_. We recommend using
`Docker images <https://element-hq.github.io/synapse/latest/setup/installation.html#docker-images-and-ansible-playbooks>`_ or `Debian packages from Matrix.org
<https://element-hq.github.io/synapse/latest/setup/installation.html#matrixorg-packages>`_.
.. _federation:
Synapse has a variety of `config options
<https://element-hq.github.io/synapse/latest/usage/configuration/config_documentation.html>`_
which can be used to customise its behaviour after installation.
There are additional details on how to `configure Synapse for federation here
<https://element-hq.github.io/synapse/latest/federate.html>`_.
.. _reverse-proxy:
Using a reverse proxy with Synapse
----------------------------------
It is recommended to put a reverse proxy such as
`nginx <https://nginx.org/en/docs/http/ngx_http_proxy_module.html>`_,
`Apache <https://httpd.apache.org/docs/current/mod/mod_proxy_http.html>`_,
`Caddy <https://caddyserver.com/docs/quick-starts/reverse-proxy>`_,
`HAProxy <https://www.haproxy.org/>`_ or
`relayd <https://man.openbsd.org/relayd.8>`_ in front of Synapse. One advantage of
doing so is that it means that you can expose the default https port (443) to
Matrix clients without needing to run Synapse with root privileges.
For information on configuring one, see `the reverse proxy docs
<https://element-hq.github.io/synapse/latest/reverse_proxy.html>`_.
Upgrading an existing Synapse
-----------------------------
The instructions for upgrading Synapse are in `the upgrade notes`_.
Please check these instructions as upgrading may require extra steps for some
versions of Synapse.
.. _the upgrade notes: https://element-hq.github.io/synapse/develop/upgrade.html
Platform dependencies
---------------------
Synapse uses a number of platform dependencies such as Python and PostgreSQL,
and aims to follow supported upstream versions. See the
`deprecation policy <https://element-hq.github.io/synapse/latest/deprecation_policy.html>`_
for more details.
Security note
-------------
Matrix serves raw, user-supplied data in some APIs -- specifically the `content
repository endpoints`_.
.. _content repository endpoints: https://matrix.org/docs/spec/client_server/latest.html#get-matrix-media-r0-download-servername-mediaid
Whilst we make a reasonable effort to mitigate against XSS attacks (for
instance, by using `CSP`_), a Matrix homeserver should not be hosted on a
domain hosting other web applications. This especially applies to sharing
the domain with Matrix web clients and other sensitive applications like
webmail. See
https://developer.github.com/changes/2014-04-25-user-content-security for more
information.
.. _CSP: https://github.com/matrix-org/synapse/pull/1021
Ideally, the homeserver should not simply be on a different subdomain, but on
a completely different `registered domain`_ (also known as top-level site or
eTLD+1). This is because `some attacks`_ are still possible as long as the two
applications share the same registered domain.
.. _registered domain: https://tools.ietf.org/html/draft-ietf-httpbis-rfc6265bis-03#section-2.3
.. _some attacks: https://en.wikipedia.org/wiki/Session_fixation#Attacks_using_cross-subdomain_cookie
To illustrate this with an example, if your Element Web or other sensitive web
application is hosted on ``A.example1.com``, you should ideally host Synapse on
``example2.com``. Some amount of protection is offered by hosting on
``B.example1.com`` instead, so this is also acceptable in some scenarios.
However, you should *not* host your Synapse on ``A.example1.com``.
Note that all of the above refers exclusively to the domain used in Synapse's
``public_baseurl`` setting. In particular, it has no bearing on the domain
mentioned in MXIDs hosted on that server.
Following this advice ensures that even if an XSS is found in Synapse, the
impact to other applications will be minimal.
🧪 Testing a new installation
=============================
The easiest way to try out your new Synapse installation is by connecting to it
from a web client.
Unless you are running a test instance of Synapse on your local machine, in
general, you will need to enable TLS support before you can successfully
connect from a client: see
`TLS certificates <https://element-hq.github.io/synapse/latest/setup/installation.html#tls-certificates>`_.
An easy way to get started is to login or register via Element at
https://app.element.io/#/login or https://app.element.io/#/register respectively.
You will need to change the server you are logging into from ``matrix.org``
and instead specify a Homeserver URL of ``https://<server_name>:8448``
(or just ``https://<server_name>`` if you are using a reverse proxy).
If you prefer to use another client, refer to our
`client breakdown <https://matrix.org/ecosystem/clients/>`_.
If all goes well you should at least be able to log in, create a room, and
start sending messages.
.. _`client-user-reg`:
Registering a new user from a client
------------------------------------
By default, registration of new users via Matrix clients is disabled. To enable
it:
1. In the
`registration config section <https://element-hq.github.io/synapse/latest/usage/configuration/config_documentation.html#registration>`_
set ``enable_registration: true`` in ``homeserver.yaml``.
2. Then **either**:
a. set up a `CAPTCHA <https://element-hq.github.io/synapse/latest/CAPTCHA_SETUP.html>`_, or
b. set ``enable_registration_without_verification: true`` in ``homeserver.yaml``.
We **strongly** recommend using a CAPTCHA, particularly if your homeserver is exposed to
the public internet. Without it, anyone can freely register accounts on your homeserver.
This can be exploited by attackers to create spambots targetting the rest of the Matrix
federation.
Your new user name will be formed partly from the ``server_name``, and partly
from a localpart you specify when you create the account. Your name will take
the form of::
@localpart:my.domain.name
(pronounced "at localpart on my dot domain dot name").
As when logging in, you will need to specify a "Custom server". Specify your
desired ``localpart`` in the 'User name' box.
🎯 Troubleshooting and support
==============================
🚀 Professional support
-----------------------
Enterprise quality support for Synapse including SLAs is available as part of an
`Element Server Suite (ESS) <https://element.io/pricing>`_ subscription.
If you are an existing ESS subscriber then you can raise a `support request <https://ems.element.io/support>`_
and access the `knowledge base <https://ems-docs.element.io>`_.
🤝 Community support
--------------------
The `Admin FAQ <https://element-hq.github.io/synapse/latest/usage/administration/admin_faq.html>`_
includes tips on dealing with some common problems. For more details, see
`Synapse's wider documentation <https://element-hq.github.io/synapse/latest/>`_.
For additional support installing or managing Synapse, please ask in the community
support room |room|_ (from a matrix.org account if necessary). We do not use GitHub
issues for support requests, only for bug reports and feature requests.
.. |room| replace:: ``#synapse:matrix.org``
.. _room: https://matrix.to/#/#synapse:matrix.org
.. |docs| replace:: ``docs``
.. _docs: docs
🪪 Identity Servers
===================
Identity servers have the job of mapping email addresses and other 3rd Party
IDs (3PIDs) to Matrix user IDs, as well as verifying the ownership of 3PIDs
before creating that mapping.
**They are not where accounts or credentials are stored - these live on home
servers. Identity Servers are just for mapping 3rd party IDs to matrix IDs.**
This process is very security-sensitive, as there is obvious risk of spam if it
is too easy to sign up for Matrix accounts or harvest 3PID data. In the longer
term, we hope to create a decentralised system to manage it (`matrix-doc #712
<https://github.com/matrix-org/matrix-doc/issues/712>`_), but in the meantime,
the role of managing trusted identity in the Matrix ecosystem is farmed out to
a cluster of known trusted ecosystem partners, who run 'Matrix Identity
Servers' such as `Sydent <https://github.com/matrix-org/sydent>`_, whose role
is purely to authenticate and track 3PID logins and publish end-user public
keys.
You can host your own copy of Sydent, but this will prevent you reaching other
users in the Matrix ecosystem via their email address, and prevent them finding
you. We therefore recommend that you use one of the centralised identity servers
at ``https://matrix.org`` or ``https://vector.im`` for now.
To reiterate: the Identity server will only be used if you choose to associate
an email address with your account, or send an invite to another user via their
email address.
🛠️ Development
==============
We welcome contributions to Synapse from the community!
The best place to get started is our
`guide for contributors <https://element-hq.github.io/synapse/latest/development/contributing_guide.html>`_.
This is part of our larger `documentation <https://element-hq.github.io/synapse/latest>`_, which includes
information for Synapse developers as well as Synapse administrators.
Developers might be particularly interested in:
* `Synapse's database schema <https://element-hq.github.io/synapse/latest/development/database_schema.html>`_,
* `notes on Synapse's implementation details <https://element-hq.github.io/synapse/latest/development/internal_documentation/index.html>`_, and
* `how we use git <https://element-hq.github.io/synapse/latest/development/git.html>`_.
Alongside all that, join our developer community on Matrix:
`#synapse-dev:matrix.org <https://matrix.to/#/#synapse-dev:matrix.org>`_, featuring real humans!
.. |support| image:: https://img.shields.io/badge/matrix-community%20support-success
:alt: (get community support in #synapse:matrix.org)
:target: https://matrix.to/#/#synapse:matrix.org
.. |development| image:: https://img.shields.io/matrix/synapse-dev:matrix.org?label=development&logo=matrix
:alt: (discuss development on #synapse-dev:matrix.org)
:target: https://matrix.to/#/#synapse-dev:matrix.org
.. |documentation| image:: https://img.shields.io/badge/documentation-%E2%9C%93-success
:alt: (Rendered documentation on GitHub Pages)
:target: https://element-hq.github.io/synapse/latest/
.. |license| image:: https://img.shields.io/github/license/element-hq/synapse
:alt: (check license in LICENSE file)
:target: LICENSE
.. |pypi| image:: https://img.shields.io/pypi/v/matrix-synapse
:alt: (latest version released on PyPi)
:target: https://pypi.org/project/matrix-synapse
.. |python| image:: https://img.shields.io/pypi/pyversions/matrix-synapse
:alt: (supported python versions)
:target: https://pypi.org/project/matrix-synapse