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<h1id="upgrading-to-v1890"><aclass="header"href="#upgrading-to-v1890">Upgrading to v1.89.0</a></h1>
<h2id="removal-of-unspecced-user-property-for-register"><aclass="header"href="#removal-of-unspecced-user-property-for-register">Removal of unspecced <code>user</code> property for <code>/register</code></a></h2>
<p>Application services can no longer call <code>/register</code> with a <code>user</code> property to create new users.
The standard <code>username</code> property should be used instead. See the
<ahref="https://spec.matrix.org/v1.7/application-service-api/#server-admin-style-permissions">Application Service specification</a>
<p>The minimum supported Python version has been increased from v3.7 to v3.8.
You will need Python 3.8 to run Synapse v1.88.0 (due out July 18th, 2023).</p>
<p>If you use current versions of the Matrix.org-distributed Debian
packages or Docker images, no action is required.</p>
<h2id="removal-of-worker_replication_-settings"><aclass="header"href="#removal-of-worker_replication_-settings">Removal of <code>worker_replication_*</code> settings</a></h2>
<p>As mentioned previously in <ahref="#upgrading-to-v1840">Upgrading to v1.84.0</a>, the following deprecated settings
<h1id="upgrading-to-v1850"><aclass="header"href="#upgrading-to-v1850">Upgrading to v1.85.0</a></h1>
<h2id="application-service-registration-with-user-property-deprecation"><aclass="header"href="#application-service-registration-with-user-property-deprecation">Application service registration with "user" property deprecation</a></h2>
<p>Application services should ensure they call the <code>/register</code> endpoint with a
<code>username</code> property. The legacy <code>user</code> property is considered deprecated and
should no longer be included.</p>
<p>A future version of Synapse (v1.88.0 or later) will remove support for legacy
<h1id="upgrading-to-v1840"><aclass="header"href="#upgrading-to-v1840">Upgrading to v1.84.0</a></h1>
<h2id="deprecation-of-worker_replication_-configuration-settings"><aclass="header"href="#deprecation-of-worker_replication_-configuration-settings">Deprecation of <code>worker_replication_*</code> configuration settings</a></h2>
<h1id="upgrading-to-v1810"><aclass="header"href="#upgrading-to-v1810">Upgrading to v1.81.0</a></h1>
<h2id="application-service-path--authentication-deprecations"><aclass="header"href="#application-service-path--authentication-deprecations">Application service path & authentication deprecations</a></h2>
<p>Synapse now attempts the versioned appservice paths before falling back to the
<h1id="upgrading-to-v1790"><aclass="header"href="#upgrading-to-v1790">Upgrading to v1.79.0</a></h1>
<h2id="the-on_threepid_bind-module-callback-method-has-been-deprecated"><aclass="header"href="#the-on_threepid_bind-module-callback-method-has-been-deprecated">The <code>on_threepid_bind</code> module callback method has been deprecated</a></h2>
<h1id="upgrading-to-v1780"><aclass="header"href="#upgrading-to-v1780">Upgrading to v1.78.0</a></h1>
<h2id="deprecate-the-_synapseadminv1mediaserver_namedelete-admin-api"><aclass="header"href="#deprecate-the-_synapseadminv1mediaserver_namedelete-admin-api">Deprecate the <code>/_synapse/admin/v1/media/<server_name>/delete</code> admin API</a></h2>
<p>Synapse 1.78.0 replaces the <code>/_synapse/admin/v1/media/<server_name>/delete</code>
admin API with an identical endpoint at <code>/_synapse/admin/v1/media/delete</code>. Please
update your tooling to use the new endpoint. The deprecated version will be removed
<h1id="upgrading-to-v1760"><aclass="header"href="#upgrading-to-v1760">Upgrading to v1.76.0</a></h1>
<h2id="faster-joins-are-enabled-by-default"><aclass="header"href="#faster-joins-are-enabled-by-default">Faster joins are enabled by default</a></h2>
<p>When joining a room for the first time, Synapse 1.76.0 will request a partial join from the other server by default. Previously, server admins had to opt-in to this using an experimental config flag.</p>
<p>Server admins can opt out of this feature for the time being by setting</p>
<pre><codeclass="language-yaml">experimental:
faster_joins: false
</code></pre>
<p>in their server config.</p>
<h2id="changes-to-the-account-data-replication-streams"><aclass="header"href="#changes-to-the-account-data-replication-streams">Changes to the account data replication streams</a></h2>
<p>Synapse has changed the format of the account data and devices replication
streams (between workers). This is a forwards- and backwards-incompatible
change: v1.75 workers cannot process account data replicated by v1.76 workers,
and vice versa.</p>
<p>Once all workers are upgraded to v1.76 (or downgraded to v1.75), account data
and device replication will resume as normal.</p>
<h2id="minimum-version-of-poetry-is-now-132"><aclass="header"href="#minimum-version-of-poetry-is-now-132">Minimum version of Poetry is now 1.3.2</a></h2>
<p>The minimum supported version of Poetry is now 1.3.2 (previously 1.2.0, <ahref="#upgrading-to-v1670">since
Synapse 1.67</a>). If you have used <code>poetry install</code> to
install Synapse from a source checkout, you should upgrade poetry: see its
<h1id="upgrading-to-v1740"><aclass="header"href="#upgrading-to-v1740">Upgrading to v1.74.0</a></h1>
<h2id="unicode-support-in-user-search"><aclass="header"href="#unicode-support-in-user-search">Unicode support in user search</a></h2>
<p>This version introduces optional support for an <ahref="https://github.com/matrix-org/synapse/pull/14464">improved user search dealing with Unicode characters</a>.</p>
<p>If you want to take advantage of this feature you need to install PyICU,
the ICU native dependency and its development headers
so that PyICU can build since no prebuilt wheels are available.</p>
<p>You can follow <ahref="https://pypi.org/project/PyICU/">the PyICU documentation</a> to do so,
<h1id="upgrading-to-v1730"><aclass="header"href="#upgrading-to-v1730">Upgrading to v1.73.0</a></h1>
<h2id="legacy-prometheus-metric-names-have-now-been-removed"><aclass="header"href="#legacy-prometheus-metric-names-have-now-been-removed">Legacy Prometheus metric names have now been removed</a></h2>
<p>Synapse v1.69.0 included the deprecation of legacy Prometheus metric names
and offered an option to disable them.
Synapse v1.71.0 disabled legacy Prometheus metric names by default.</p>
<p>This version, v1.73.0, removes those legacy Prometheus metric names entirely.
This also means that the <code>enable_legacy_metrics</code> configuration option has been
removed; it will no longer be possible to re-enable the legacy metric names.</p>
<p>If you use metrics and have not yet updated your Grafana dashboard(s),
Prometheus console(s) or alerting rule(s), please consider doing so when upgrading
to this version.
Note that the included Grafana dashboard was updated in v1.72.0 to correct some
metric names which were missed when legacy metrics were disabled by default.</p>
<p>See <ahref="#deprecation-of-legacy-prometheus-metric-names">v1.69.0: Deprecation of legacy Prometheus metric names</a>
<h1id="upgrading-to-v1710"><aclass="header"href="#upgrading-to-v1710">Upgrading to v1.71.0</a></h1>
<h2id="removal-of-the-generate_short_term_login_token-module-api-method"><aclass="header"href="#removal-of-the-generate_short_term_login_token-module-api-method">Removal of the <code>generate_short_term_login_token</code> module API method</a></h2>
<p>As announced with the release of <ahref="#deprecation-of-the-generate_short_term_login_token-module-api-method">Synapse 1.69.0</a>, the deprecated <code>generate_short_term_login_token</code> module method has been removed.</p>
<p>Modules relying on it can instead use the <code>create_login_token</code> method.</p>
<h2id="changes-to-the-events-received-by-application-services-interest"><aclass="header"href="#changes-to-the-events-received-by-application-services-interest">Changes to the events received by application services (interest)</a></h2>
<p>To align with spec (changed in
<ahref="https://github.com/matrix-org/matrix-spec-proposals/pull/3905">MSC3905</a>), Synapse now
only considers local users to be interesting. In other words, the <code>users</code> namespace
regex is only be applied against local users of the homeserver.</p>
<p>Please note, this probably doesn't affect the expected behavior of your application
service, since an interesting local user in a room still means all messages in the room
(from local or remote users) will still be considered interesting. And matching a room
with the <code>rooms</code> or <code>aliases</code> namespace regex will still consider all events sent in the
room to be interesting to the application service.</p>
<p>If one of your application service's <code>users</code> regex was intending to match a remote user,
this will no longer match as you expect. The behavioral mismatch between matching all
local users and some remote users is why the spec was changed/clarified and this
caveat is no longer supported.</p>
<h2id="legacy-prometheus-metric-names-are-now-disabled-by-default"><aclass="header"href="#legacy-prometheus-metric-names-are-now-disabled-by-default">Legacy Prometheus metric names are now disabled by default</a></h2>
<p>Synapse v1.71.0 disables legacy Prometheus metric names by default.
For administrators that still rely on them and have not yet had chance to update their
uses of the metrics, it's still possible to specify <code>enable_legacy_metrics: true</code> in
the configuration to re-enable them temporarily.</p>
<p>Synapse v1.73.0 will <strong>remove legacy metric names altogether</strong> and at that point,
it will no longer be possible to re-enable them.</p>
<p>If you do not use metrics or you have already updated your Grafana dashboard(s),
Prometheus console(s) and alerting rule(s), there is no action needed.</p>
<p>See <ahref="#deprecation-of-legacy-prometheus-metric-names">v1.69.0: Deprecation of legacy Prometheus metric names</a>.</p>
<h1id="upgrading-to-v1690"><aclass="header"href="#upgrading-to-v1690">Upgrading to v1.69.0</a></h1>
<h2id="changes-to-the-receipts-replication-streams"><aclass="header"href="#changes-to-the-receipts-replication-streams">Changes to the receipts replication streams</a></h2>
<p>Synapse now includes information indicating if a receipt applies to a thread when
replicating it to other workers. This is a forwards- and backwards-incompatible
change: v1.68 and workers cannot process receipts replicated by v1.69 workers, and
vice versa.</p>
<p>Once all workers are upgraded to v1.69 (or downgraded to v1.68), receipts
replication will resume as normal.</p>
<h2id="deprecation-of-legacy-prometheus-metric-names"><aclass="header"href="#deprecation-of-legacy-prometheus-metric-names">Deprecation of legacy Prometheus metric names</a></h2>
<p>In current versions of Synapse, some Prometheus metrics are emitted under two different names,
with one of the names being older but non-compliant with OpenMetrics and Prometheus conventions
and one of the names being newer but compliant.</p>
<p>Synapse v1.71.0 will turn the old metric names off <em>by default</em>.
For administrators that still rely on them and have not had chance to update their
uses of the metrics, it's possible to specify <code>enable_legacy_metrics: true</code> in
the configuration to re-enable them temporarily.</p>
<p>Synapse v1.73.0 will <strong>remove legacy metric names altogether</strong> and it will no longer
be possible to re-enable them.</p>
<p>The Grafana dashboard, Prometheus recording rules and Prometheus Consoles included
in the <code>contrib</code> directory in the Synapse repository have been updated to no longer
rely on the legacy names. These can be used on a current version of Synapse
because current versions of Synapse emit both old and new names.</p>
<p>You may need to update your alerting rules or any other rules that depend on
the names of Prometheus metrics.
If you want to test your changes before legacy names are disabled by default,
you may specify <code>enable_legacy_metrics: false</code> in your homeserver configuration.</p>
<p>A list of affected metrics is available on the <ahref="https://matrix-org.github.io/synapse/v1.69/metrics-howto.html?highlight=metrics%20deprecated#renaming-of-metrics--deprecation-of-old-names-in-12">Metrics How-to page</a>.</p>
<h2id="deprecation-of-the-generate_short_term_login_token-module-api-method"><aclass="header"href="#deprecation-of-the-generate_short_term_login_token-module-api-method">Deprecation of the <code>generate_short_term_login_token</code> module API method</a></h2>
<p>The following method of the module API has been deprecated, and is scheduled to
<h2id="rust-requirement-when-building-from-source"><aclass="header"href="#rust-requirement-when-building-from-source">Rust requirement when building from source.</a></h2>
<p>Building from a source checkout of Synapse now requires a recent Rust compiler
<h1id="upgrading-to-v1670"><aclass="header"href="#upgrading-to-v1670">Upgrading to v1.67.0</a></h1>
<h2id="direct-tcp-replication-is-no-longer-supported-migrate-to-redis"><aclass="header"href="#direct-tcp-replication-is-no-longer-supported-migrate-to-redis">Direct TCP replication is no longer supported: migrate to Redis</a></h2>
<p>Redis support was added in v1.13.0 with it becoming the recommended method in
v1.18.0. It replaced the old direct TCP connections (which was deprecated as of
v1.18.0) to the main process. With Redis, rather than all the workers connecting
to the main process, all the workers and the main process connect to Redis,
which relays replication commands between processes. This can give a significant
CPU saving on the main process and is a prerequisite for upcoming
performance improvements.</p>
<p>To migrate to Redis add the <ahref="./workers.html#shared-configuration"><code>redis</code> config</a>,
and remove the TCP <code>replication</code> listener from config of the master and
<code>worker_replication_port</code> from worker config. Note that a HTTP listener with a
<code>replication</code> resource is still required.</p>
<h2id="minimum-version-of-poetry-is-now-v120"><aclass="header"href="#minimum-version-of-poetry-is-now-v120">Minimum version of Poetry is now v1.2.0</a></h2>
<p>The minimum supported version of poetry is now 1.2. This should only affect
those installing from a source checkout.</p>
<h2id="rust-requirement-in-the-next-release"><aclass="header"href="#rust-requirement-in-the-next-release">Rust requirement in the next release</a></h2>
<p>From the next major release (v1.68.0) installing Synapse from a source checkout
will require a recent Rust compiler. Those using packages or
<code>pip install matrix-synapse</code> will not be affected.</p>
<p>The simplest way of installing Rust is via <ahref="https://rustup.rs/">rustup.rs</a></p>
<h2id="sqlite-version-requirement-in-the-next-release"><aclass="header"href="#sqlite-version-requirement-in-the-next-release">SQLite version requirement in the next release</a></h2>
<h1id="upgrading-to-v1660"><aclass="header"href="#upgrading-to-v1660">Upgrading to v1.66.0</a></h1>
<h2id="delegation-of-email-validation-no-longer-supported"><aclass="header"href="#delegation-of-email-validation-no-longer-supported">Delegation of email validation no longer supported</a></h2>
<p>As of this version, Synapse no longer allows the tasks of verifying email address
ownership, and password reset confirmation, to be delegated to an identity server.
This removal was previously planned for Synapse 1.64.0, but was
<ahref="https://github.com/matrix-org/synapse/issues/13421">delayed</a> until now to give
homeserver administrators more notice of the change.</p>
<p>To continue to allow users to add email addresses to their homeserver accounts,
and perform password resets, make sure that Synapse is configured with a working
email server in the <ahref="https://matrix-org.github.io/synapse/latest/usage/configuration/config_documentation.html#email"><code>email</code> configuration
section</a>
(including, at a minimum, a <code>notif_from</code> setting.)</p>
<p>Specifying an <code>email</code> setting under <code>account_threepid_delegates</code> will now cause
<h1id="upgrading-to-v1640"><aclass="header"href="#upgrading-to-v1640">Upgrading to v1.64.0</a></h1>
<h2id="deprecation-of-the-ability-to-delegate-e-mail-verification-to-identity-servers"><aclass="header"href="#deprecation-of-the-ability-to-delegate-e-mail-verification-to-identity-servers">Deprecation of the ability to delegate e-mail verification to identity servers</a></h2>
<p>Synapse v1.66.0 will remove the ability to delegate the tasks of verifying email address ownership, and password reset confirmation, to an identity server.</p>
<p>If you require your homeserver to verify e-mail addresses or to support password resets via e-mail, please configure your homeserver with SMTP access so that it can send e-mails on its own behalf.
<ahref="https://matrix-org.github.io/synapse/latest/usage/configuration/config_documentation.html#email">Consult the configuration documentation for more information.</a></p>
<p>The option that will be removed is <code>account_threepid_delegates.email</code>.</p>
<h2id="changes-to-the-event-replication-streams"><aclass="header"href="#changes-to-the-event-replication-streams">Changes to the event replication streams</a></h2>
<p>Synapse now includes a flag indicating if an event is an outlier when
replicating it to other workers. This is a forwards- and backwards-incompatible
change: v1.63 and workers cannot process events replicated by v1.64 workers, and
vice versa.</p>
<p>Once all workers are upgraded to v1.64 (or downgraded to v1.63), event
<h1id="upgrading-to-v1620"><aclass="header"href="#upgrading-to-v1620">Upgrading to v1.62.0</a></h1>
<h2id="new-signatures-for-spam-checker-callbacks"><aclass="header"href="#new-signatures-for-spam-checker-callbacks">New signatures for spam checker callbacks</a></h2>
<p>As a followup to changes in v1.60.0, the following spam-checker callbacks have changed signature:</p>
<ul>
<li><code>user_may_join_room</code></li>
<li><code>user_may_invite</code></li>
<li><code>user_may_send_3pid_invite</code></li>
<li><code>user_may_create_room</code></li>
<li><code>user_may_create_room_alias</code></li>
<li><code>user_may_publish_room</code></li>
<li><code>check_media_file_for_spam</code></li>
</ul>
<p>For each of these methods, the previous callback signature has been deprecated.</p>
<p>Whereas callbacks used to return <code>bool</code>, they should now return <code>Union["synapse.module_api.NOT_SPAM", "synapse.module_api.errors.Codes"]</code>.</p>
<p>For instance, if your module implements <code>user_may_join_room</code> as follows:</p>
<h1id="upgrading-to-v1610"><aclass="header"href="#upgrading-to-v1610">Upgrading to v1.61.0</a></h1>
<h2id="removal-of-deprecated-communitygroups"><aclass="header"href="#removal-of-deprecated-communitygroups">Removal of deprecated community/groups</a></h2>
<p>This release of Synapse will remove deprecated community/groups from codebase.</p>
<h1id="upgrading-to-v1600"><aclass="header"href="#upgrading-to-v1600">Upgrading to v1.60.0</a></h1>
<h2id="adding-a-new-unique-index-to-state_group_edges-could-fail-if-your-database-is-corrupted"><aclass="header"href="#adding-a-new-unique-index-to-state_group_edges-could-fail-if-your-database-is-corrupted">Adding a new unique index to <code>state_group_edges</code> could fail if your database is corrupted</a></h2>
<p>This release of Synapse will add a unique index to the <code>state_group_edges</code> table, in order
to prevent accidentally introducing duplicate information (for example, because a database
backup was restored multiple times).</p>
<p>Duplicate rows being present in this table could cause drastic performance problems; see
<ahref="https://github.com/matrix-org/synapse/issues/11779">issue 11779</a> for more details.</p>
<p>If your Synapse database already has had duplicate rows introduced into this table,
this could fail, with either of these errors:</p>
<p><strong>On Postgres:</strong></p>
<pre><code>synapse.storage.background_updates - 623 - INFO - background_updates-0 - Adding index state_group_edges_unique_idx to state_group_edges
<p>At the command-line, use <code>sqlite3 path/to/your-homeserver-database.db</code>:</p>
<pre><codeclass="language-sql">BEGIN;
DELETE FROM state_group_edges WHERE (rowid, state_group, prev_state_group) IN (
SELECT row_id, state_group, prev_state_group
FROM (
SELECT
rowid AS row_id,
MIN(rowid) OVER (PARTITION BY state_group, prev_state_group) AS min_row_id,
state_group,
prev_state_group
FROM state_group_edges
)
WHERE row_id <> min_row_id
);
COMMIT;
</code></pre>
<h3id="for-more-details"><aclass="header"href="#for-more-details">For more details</a></h3>
<p><ahref="https://github.com/matrix-org/synapse/issues/11779#issuecomment-1131545970">This comment on issue 11779</a>
has queries that can be used to check a database for this problem in advance.</p>
</details>
<h2id="new-signature-for-the-spam-checker-callback-check_event_for_spam"><aclass="header"href="#new-signature-for-the-spam-checker-callback-check_event_for_spam">New signature for the spam checker callback <code>check_event_for_spam</code></a></h2>
<p>The previous signature has been deprecated.</p>
<p>Whereas <code>check_event_for_spam</code> callbacks used to return <code>Union[str, bool]</code>, they should now return <code>Union["synapse.module_api.NOT_SPAM", "synapse.module_api.errors.Codes"]</code>.</p>
<p>This is part of an ongoing refactoring of the SpamChecker API to make it less ambiguous and more powerful.</p>
<p>If your module implements <code>check_event_for_spam</code> as follows:</p>
<h1id="upgrading-to-v1590"><aclass="header"href="#upgrading-to-v1590">Upgrading to v1.59.0</a></h1>
<h2id="device-name-lookup-over-federation-has-been-disabled-by-default"><aclass="header"href="#device-name-lookup-over-federation-has-been-disabled-by-default">Device name lookup over federation has been disabled by default</a></h2>
<p>The names of user devices are no longer visible to users on other homeservers by default.
Device IDs are unaffected, as these are necessary to facilitate end-to-end encryption.</p>
homeserver config option to <code>true</code>.</p>
<h2id="deprecation-of-the-synapseappappservice-and-synapseappuser_dir-worker-application-types"><aclass="header"href="#deprecation-of-the-synapseappappservice-and-synapseappuser_dir-worker-application-types">Deprecation of the <code>synapse.app.appservice</code> and <code>synapse.app.user_dir</code> worker application types</a></h2>
<p>The <code>synapse.app.appservice</code> worker application type allowed you to configure a
single worker to use to notify application services of new events, as long
as this functionality was disabled on the main process with <code>notify_appservices: False</code>.
Further, the <code>synapse.app.user_dir</code> worker application type allowed you to configure
a single worker to be responsible for updating the user directory, as long as this
was disabled on the main process with <code>update_user_directory: False</code>.</p>
<p>To unify Synapse's worker types, the <code>synapse.app.appservice</code> worker application
type and the <code>notify_appservices</code> configuration option have been deprecated.
The <code>synapse.app.user_dir</code> worker application type and <code>update_user_directory</code>
configuration option have also been deprecated.</p>
<p>To get the same functionality as was provided by the deprecated options, it's now recommended that the <code>synapse.app.generic_worker</code>
worker application type is used and that the <code>notify_appservices_from_worker</code> and/or
<code>update_user_directory_from_worker</code> options are set to the name of a worker.</p>
<p>For the time being, the old options can be used alongside the new options to make
it easier to transition between the two configurations, however please note that:</p>
<ul>
<li>the options must not contradict each other (otherwise Synapse won't start); and</li>
<li>the <code>notify_appservices</code> and <code>update_user_directory</code> options will be removed in a future release of Synapse.</li>
</ul>
<p>Please see the <ahref="workers.html#notifying-application-services"><em>Notifying Application Services</em></a> and
<ahref="workers.html#updating-the-user-directory"><em>Updating the User Directory</em></a> sections of the worker
<h1id="upgrading-to-v1580"><aclass="header"href="#upgrading-to-v1580">Upgrading to v1.58.0</a></h1>
<h2id="groupscommunities-feature-has-been-disabled-by-default"><aclass="header"href="#groupscommunities-feature-has-been-disabled-by-default">Groups/communities feature has been disabled by default</a></h2>
<p>The non-standard groups/communities feature in Synapse has been disabled by default
<h1id="upgrading-to-v1570"><aclass="header"href="#upgrading-to-v1570">Upgrading to v1.57.0</a></h1>
<h2id="changes-to-database-schema-for-application-services"><aclass="header"href="#changes-to-database-schema-for-application-services">Changes to database schema for application services</a></h2>
<p>Synapse v1.57.0 includes a <ahref="https://github.com/matrix-org/synapse/pull/12209">change</a> to the
way transaction IDs are managed for application services. If your deployment uses a dedicated
worker for application service traffic, <strong>it must be stopped</strong> when the database is upgraded
(which normally happens when the main process is upgraded), to ensure the change is made safely
without any risk of reusing transaction IDs.</p>
<p>Deployments which do not use separate worker processes can be upgraded as normal. Similarly,
deployments where no application services are in use can be upgraded as normal.</p>
<details>
<summary><b>Recovering from an incorrect upgrade</b></summary>
<p>If the database schema is upgraded <em>without</em> stopping the worker responsible
for AS traffic, then the following error may be given when attempting to start
<h2id="open-registration-without-verification-is-now-disabled-by-default"><aclass="header"href="#open-registration-without-verification-is-now-disabled-by-default">Open registration without verification is now disabled by default</a></h2>
<p>Synapse will refuse to start if registration is enabled without email, captcha, or token-based verification unless the new config
flag <code>enable_registration_without_verification</code> is set to "true".</p>
<h2id="groupscommunities-feature-has-been-deprecated"><aclass="header"href="#groupscommunities-feature-has-been-deprecated">Groups/communities feature has been deprecated</a></h2>
<p>The non-standard groups/communities feature in Synapse has been deprecated and will
be disabled by default in Synapse v1.58.0.</p>
<p>You can test disabling it by adding the following to your homeserver configuration:</p>
<h2id="change-in-behaviour-for-postgresql-databases-with-unsafe-locale"><aclass="header"href="#change-in-behaviour-for-postgresql-databases-with-unsafe-locale">Change in behaviour for PostgreSQL databases with unsafe locale</a></h2>
<p>Synapse now refuses to start when using PostgreSQL with non-<code>C</code> values for <code>COLLATE</code> and
<code>CTYPE</code> unless the config flag <code>allow_unsafe_locale</code>, found in the database section of
the configuration file, is set to <code>true</code>. See the <ahref="https://matrix-org.github.io/synapse/latest/postgres.html#fixing-incorrect-collate-or-ctype">PostgreSQL documentation</a>
for more information and instructions on how to fix a database with incorrect values.</p>
to your Python installation's <code>bin</code>. This should be on your <code>PATH</code>
automatically, though you might need to activate a virtual environment
depending on how you installed Synapse.</li>
</ul>
<h2id="compatibility-dropped-for-mjolnir-131-and-earlier"><aclass="header"href="#compatibility-dropped-for-mjolnir-131-and-earlier">Compatibility dropped for Mjolnir 1.3.1 and earlier</a></h2>
<p>Synapse v1.55.0 drops support for Mjolnir 1.3.1 and earlier.
If you use the Mjolnir module to moderate your homeserver,
please upgrade Mjolnir to version 1.3.2 or later before upgrading Synapse.</p>
<h1id="upgrading-to-v1530"><aclass="header"href="#upgrading-to-v1530">Upgrading to v1.53.0</a></h1>
<h2id="dropping-support-for-webclient-listeners-and-non-https-web_client_location"><aclass="header"href="#dropping-support-for-webclient-listeners-and-non-https-web_client_location">Dropping support for <code>webclient</code> listeners and non-HTTP(S) <code>web_client_location</code></a></h2>
<p>Per the deprecation notice in Synapse v1.51.0, listeners of type <code>webclient</code>
are no longer supported and configuring them is a now a configuration error.</p>
<p>Configuring a non-HTTP(S) <code>web_client_location</code> configuration is is now a
configuration error. Since the <code>webclient</code> listener is no longer supported, this
setting only applies to the root path <code>/</code> of Synapse's web server and no longer
the <code>/_matrix/client/</code> path.</p>
<h2id="stablisation-of-msc3231"><aclass="header"href="#stablisation-of-msc3231">Stablisation of MSC3231</a></h2>
<p>Please update any relevant reverse proxy or firewall configurations appropriately.</p>
<h2id="time-based-cache-expiry-is-now-enabled-by-default"><aclass="header"href="#time-based-cache-expiry-is-now-enabled-by-default">Time-based cache expiry is now enabled by default</a></h2>
<p>Formerly, entries in the cache were not evicted regardless of whether they were accessed after storing.
The <code>expiry_time</code> flag will still continue to work, but it has been deprecated and will be removed in the future.</p>
<h2id="deprecation-of-capability-orgmatrixmsc3283"><aclass="header"href="#deprecation-of-capability-orgmatrixmsc3283">Deprecation of <code>capability</code><code>org.matrix.msc3283.*</code></a></h2>
<p>The <code>capabilities</code> of MSC3283 from the REST API <code>/_matrix/client/r0/capabilities</code>
<p>are deprecated and scheduled to be removed in Synapse v1.54.0.</p>
<p>The new <code>capabilities</code></p>
<ul>
<li><code>m.set_displayname</code>,</li>
<li><code>m.set_avatar_url</code> and</li>
<li><code>m.3pid_changes</code></li>
</ul>
<p>are now active by default.</p>
<h2id="removal-of-user_may_create_room_with_invites"><aclass="header"href="#removal-of-user_may_create_room_with_invites">Removal of <code>user_may_create_room_with_invites</code></a></h2>
<p>As announced with the release of <ahref="#deprecation-of-the-user_may_create_room_with_invites-module-callback">Synapse 1.47.0</a>,
the deprecated <code>user_may_create_room_with_invites</code> module callback has been removed.</p>
<p>Modules relying on it can instead implement <ahref="https://matrix-org.github.io/synapse/latest/modules/spam_checker_callbacks.html#user_may_invite"><code>user_may_invite</code></a>
and use the <ahref="https://github.com/matrix-org/synapse/blob/872f23b95fa980a61b0866c1475e84491991fa20/synapse/module_api/__init__.py#L869-L876"><code>get_room_state</code></a>
module API to infer whether the invite is happening while creating a room (see <ahref="https://github.com/matrix-org/synapse-domain-rule-checker/blob/e7d092dd9f2a7f844928771dbfd9fd24c2332e48/synapse_domain_rule_checker/__init__.py#L56-L89">this function</a>
as an example). Alternately, modules can also implement <ahref="https://matrix-org.github.io/synapse/latest/modules/third_party_rules_callbacks.html#on_create_room"><code>on_create_room</code></a>.</p>
<h1id="upgrading-to-v1510"><aclass="header"href="#upgrading-to-v1510">Upgrading to v1.51.0</a></h1>
<h2id="deprecation-of-webclient-listeners-and-non-https-web_client_location"><aclass="header"href="#deprecation-of-webclient-listeners-and-non-https-web_client_location">Deprecation of <code>webclient</code> listeners and non-HTTP(S) <code>web_client_location</code></a></h2>
<p>Listeners of type <code>webclient</code> are deprecated and scheduled to be removed in
Synapse v1.53.0.</p>
<p>Similarly, a non-HTTP(S) <code>web_client_location</code> configuration is deprecated and
will become a configuration error in Synapse v1.53.0.</p>
<h1id="upgrading-to-v1500"><aclass="header"href="#upgrading-to-v1500">Upgrading to v1.50.0</a></h1>
<h2id="dropping-support-for-old-python-and-postgres-versions"><aclass="header"href="#dropping-support-for-old-python-and-postgres-versions">Dropping support for old Python and Postgres versions</a></h2>
<p>In line with our <ahref="deprecation_policy.html">deprecation policy</a>,
we've dropped support for Python 3.6 and PostgreSQL 9.6, as they are no
longer supported upstream.</p>
<p>This release of Synapse requires Python 3.7+ and PostgreSQL 10+.</p>
<h1id="upgrading-to-v1470"><aclass="header"href="#upgrading-to-v1470">Upgrading to v1.47.0</a></h1>
<h2id="removal-of-old-room-admin-api"><aclass="header"href="#removal-of-old-room-admin-api">Removal of old Room Admin API</a></h2>
<p>The following admin APIs were deprecated in <ahref="https://github.com/matrix-org/synapse/blob/v1.34.0/CHANGES.md#deprecations-and-removals">Synapse 1.34</a>
(released on 2021-05-17) and have now been removed:</p>
<h2id="deprecation-of-the-user_may_create_room_with_invites-module-callback"><aclass="header"href="#deprecation-of-the-user_may_create_room_with_invites-module-callback">Deprecation of the <code>user_may_create_room_with_invites</code> module callback</a></h2>
<p>The <code>user_may_create_room_with_invites</code> is deprecated and will be removed in a future
version of Synapse. Modules implementing this callback can instead implement
and use the <ahref="https://github.com/matrix-org/synapse/blob/872f23b95fa980a61b0866c1475e84491991fa20/synapse/module_api/__init__.py#L869-L876"><code>get_room_state</code></a>
module API method to infer whether the invite is happening in the context of creating a
room.</p>
<p>We plan to remove this callback in January 2022.</p>
<h1id="upgrading-to-v1450"><aclass="header"href="#upgrading-to-v1450">Upgrading to v1.45.0</a></h1>
<h2id="changes-required-to-media-storage-provider-modules-when-reading-from-the-synapse-configuration-object"><aclass="header"href="#changes-required-to-media-storage-provider-modules-when-reading-from-the-synapse-configuration-object">Changes required to media storage provider modules when reading from the Synapse configuration object</a></h2>
<p>Media storage provider modules that read from the Synapse configuration object (i.e. that
read the value of <code>hs.config.[...]</code>) now need to specify the configuration section they're
reading from. This means that if a module reads the value of e.g. <code>hs.config.media_store_path</code>,
it needs to replace it with <code>hs.config.media.media_store_path</code>.</p>
<h1id="upgrading-to-v1440"><aclass="header"href="#upgrading-to-v1440">Upgrading to v1.44.0</a></h1>
<h2id="the-url-preview-cache-is-no-longer-mirrored-to-storage-providers"><aclass="header"href="#the-url-preview-cache-is-no-longer-mirrored-to-storage-providers">The URL preview cache is no longer mirrored to storage providers</a></h2>
<p>The <code>url_cache/</code> and <code>url_cache_thumbnails/</code> directories in the media store are
no longer mirrored to storage providers. These two directories can be safely
deleted from any configured storage providers to reclaim space.</p>
<h1id="upgrading-to-v1430"><aclass="header"href="#upgrading-to-v1430">Upgrading to v1.43.0</a></h1>
<h2id="the-spaces-summary-apis-can-now-be-handled-by-workers"><aclass="header"href="#the-spaces-summary-apis-can-now-be-handled-by-workers">The spaces summary APIs can now be handled by workers</a></h2>
<h2id="user-interactive-authentication-fallback-templates-can-now-display-errors"><aclass="header"href="#user-interactive-authentication-fallback-templates-can-now-display-errors">User-interactive authentication fallback templates can now display errors</a></h2>
<p>This may affect you if you make use of custom HTML templates for the
<ahref="https://github.com/matrix-org/synapse/tree/develop/synapse/res/templates/recaptcha.html">reCAPTCHA (<code>synapse/res/templates/recaptcha.html</code>)</a> or
<p>The template is now provided an <code>error</code> variable if the authentication
process failed. See the default templates linked above for an example.</p>
<h2id="removal-of-out-of-date-email-pushers"><aclass="header"href="#removal-of-out-of-date-email-pushers">Removal of out-of-date email pushers</a></h2>
<p>Users will stop receiving message updates via email for addresses that were
<h1id="upgrading-to-v1410"><aclass="header"href="#upgrading-to-v1410">Upgrading to v1.41.0</a></h1>
<h2id="add-support-for-routing-outbound-http-requests-via-a-proxy-for-federation"><aclass="header"href="#add-support-for-routing-outbound-http-requests-via-a-proxy-for-federation">Add support for routing outbound HTTP requests via a proxy for federation</a></h2>
<p>Since Synapse 1.6.0 (2019-11-26) you can set a proxy for outbound HTTP requests via
http_proxy/https_proxy environment variables. This proxy was set for:</p>
<ul>
<li>push</li>
<li>url previews</li>
<li>phone-home stats</li>
<li>recaptcha validation</li>
<li>CAS auth validation</li>
<li>OpenID Connect</li>
<li>Federation (checking public key revocation)</li>
</ul>
<p>In this version we have added support for outbound requests for:</p>
<ul>
<li>Outbound federation</li>
<li>Downloading remote media</li>
<li>Fetching public keys of other servers</li>
</ul>
<p>These requests use the same proxy configuration. If you have a proxy configuration we
recommend to verify the configuration. It may be necessary to adjust the <code>no_proxy</code>
environment variable.</p>
<p>See <ahref="setup/forward_proxy.html">using a forward proxy with Synapse documentation</a> for
details.</p>
<h2id="deprecation-of-template_dir"><aclass="header"href="#deprecation-of-template_dir">Deprecation of <code>template_dir</code></a></h2>
<p>The <code>template_dir</code> settings in the <code>sso</code>, <code>account_validity</code> and <code>email</code> sections of the
configuration file are now deprecated. Server admins should use the new
<code>templates.custom_template_directory</code> setting in the configuration file and use one single
custom template directory for all aforementioned features. Template file names remain
unchanged. See <ahref="https://matrix-org.github.io/synapse/latest/templates.html">the related documentation</a>
for more information and examples.</p>
<p>We plan to remove support for these settings in October 2021.</p>
<h2id="_synapseadminv1usersuseridmedia-must-be-handled-by-media-workers"><aclass="header"href="#_synapseadminv1usersuseridmedia-must-be-handled-by-media-workers"><code>/_synapse/admin/v1/users/{userId}/media</code> must be handled by media workers</a></h2>
<h1id="upgrading-to-v1390"><aclass="header"href="#upgrading-to-v1390">Upgrading to v1.39.0</a></h1>
<h2id="deprecation-of-the-current-third-party-rules-module-interface"><aclass="header"href="#deprecation-of-the-current-third-party-rules-module-interface">Deprecation of the current third-party rules module interface</a></h2>
<p>The current third-party rules module interface is deprecated in favour of the new generic
modules system introduced in Synapse v1.37.0. Authors of third-party rules modules can refer
<h1id="upgrading-to-v1380"><aclass="header"href="#upgrading-to-v1380">Upgrading to v1.38.0</a></h1>
<h2id="re-indexing-of-events-table-on-postgres-databases"><aclass="header"href="#re-indexing-of-events-table-on-postgres-databases">Re-indexing of <code>events</code> table on Postgres databases</a></h2>
<p>This release includes a database schema update which requires re-indexing one of
the larger tables in the database, <code>events</code>. This could result in increased
disk I/O for several hours or days after upgrading while the migration
completes. Furthermore, because we have to keep the old indexes until the new
indexes are ready, it could result in a significant, temporary, increase in
disk space.</p>
<p>To get a rough idea of the disk space required, check the current size of one
of the indexes. For example, from a <code>psql</code> shell, run the following sql:</p>
<p>On this server, it would be wise to ensure that at least 1152MB are free.</p>
<p>The additional disk space will be freed once the migration completes.</p>
<p>SQLite databases are unaffected by this change.</p>
<h1id="upgrading-to-v1370"><aclass="header"href="#upgrading-to-v1370">Upgrading to v1.37.0</a></h1>
<h2id="deprecation-of-the-current-spam-checker-interface"><aclass="header"href="#deprecation-of-the-current-spam-checker-interface">Deprecation of the current spam checker interface</a></h2>
<p>The current spam checker interface is deprecated in favour of a new generic modules system.
<p>The <code>room_invite_state_types</code> configuration setting has been deprecated
and replaced with <code>room_prejoin_state</code>. See the <ahref="https://github.com/matrix-org/synapse/blob/v1.34.0/docs/sample_config.yaml#L1515">sample configuration
file</a>.</p>
<p>If you have set <code>room_invite_state_types</code> to the default value you
should simply remove it from your configuration file. The default value
<p>If you have customised this value, you should remove
<code>room_invite_state_types</code> and configure <code>room_prejoin_state</code> instead.</p>
<h1id="upgrading-to-v1330"><aclass="header"href="#upgrading-to-v1330">Upgrading to v1.33.0</a></h1>
<h2id="account-validity-html-templates-can-now-display-a-users-expiration-date"><aclass="header"href="#account-validity-html-templates-can-now-display-a-users-expiration-date">Account Validity HTML templates can now display a user's expiration date</a></h2>
<p>This may affect you if you have enabled the account validity feature,
and have made use of a custom HTML template specified by the
<p>The template can now accept an <code>expiration_ts</code> variable, which
represents the unix timestamp in milliseconds for the future date of
which their account has been renewed until. See the <ahref="https://github.com/matrix-org/synapse/blob/release-v1.33.0/synapse/res/templates/account_renewed.html">default
template</a>
for an example of usage.</p>
<p>ALso note that a new HTML template, <code>account_previously_renewed.html</code>,
has been added. This is is shown to users when they attempt to renew
their account with a valid renewal token that has already been used
before. The default template contents can been found
and can also accept an <code>expiration_ts</code> variable. This template replaces
the error message users would previously see upon attempting to use a
valid renewal token more than once.</p>
<h1id="upgrading-to-v1320"><aclass="header"href="#upgrading-to-v1320">Upgrading to v1.32.0</a></h1>
<h2id="regression-causing-connected-prometheus-instances-to-become-overwhelmed"><aclass="header"href="#regression-causing-connected-prometheus-instances-to-become-overwhelmed">Regression causing connected Prometheus instances to become overwhelmed</a></h2>
<h2id="dropping-support-for-old-python-postgres-and-sqlite-versions"><aclass="header"href="#dropping-support-for-old-python-postgres-and-sqlite-versions">Dropping support for old Python, Postgres and SQLite versions</a></h2>
we've dropped support for Python 3.5 and PostgreSQL 9.5, as they are no
longer supported upstream.</p>
<p>This release of Synapse requires Python 3.6+ and PostgresSQL 9.6+ or
SQLite 3.22+.</p>
<h2id="removal-of-old-list-accounts-admin-api"><aclass="header"href="#removal-of-old-list-accounts-admin-api">Removal of old List Accounts Admin API</a></h2>
<p>The deprecated v1 "list accounts" admin API
(<code>GET /_synapse/admin/v1/users/<user_id></code>) has been removed in this
has been available since Synapse 1.7.0 (2019-12-13), and is accessible
under <code>GET /_synapse/admin/v2/users</code>.</p>
<p>The deprecation of the old endpoint was announced with Synapse 1.28.0
(released on 2021-02-25).</p>
<h2id="application-services-must-use-type-mloginapplication_service-when-registering-users"><aclass="header"href="#application-services-must-use-type-mloginapplication_service-when-registering-users">Application Services must use type <code>m.login.application_service</code> when registering users</a></h2>
<p>In compliance with the <ahref="https://matrix.org/docs/spec/application_service/r0.1.2#server-admin-style-permissions">Application Service
spec</a>,
Application Services are now required to use the
<code>m.login.application_service</code> type when registering users via the
<code>/_matrix/client/r0/register</code> endpoint. This behaviour was deprecated in
Synapse v1.30.0.</p>
<p>Please ensure your Application Services are up to date.</p>
<h1id="upgrading-to-v1290"><aclass="header"href="#upgrading-to-v1290">Upgrading to v1.29.0</a></h1>
<h2id="requirement-for-x-forwarded-proto-header"><aclass="header"href="#requirement-for-x-forwarded-proto-header">Requirement for X-Forwarded-Proto header</a></h2>
<p>When using Synapse with a reverse proxy (in particular, when using the
<h1id="upgrading-to-v1270"><aclass="header"href="#upgrading-to-v1270">Upgrading to v1.27.0</a></h1>
<h2id="changes-to-callback-uri-for-oauth2--openid-connect-and-saml2"><aclass="header"href="#changes-to-callback-uri-for-oauth2--openid-connect-and-saml2">Changes to callback URI for OAuth2 / OpenID Connect and SAML2</a></h2>
<p>This version changes the URI used for callbacks from OAuth2 and SAML2
identity providers:</p>
<ul>
<li>
<p>If your server is configured for single sign-on via an OpenID
Connect or OAuth2 identity provider, you will need to add
<code>[synapse public baseurl]/_synapse/client/oidc/callback</code> to the list
of permitted "redirect URIs" at the identity provider.</p>
<h1id="upgrading-to-v1260"><aclass="header"href="#upgrading-to-v1260">Upgrading to v1.26.0</a></h1>
<h2id="rolling-back-to-v1250-after-a-failed-upgrade"><aclass="header"href="#rolling-back-to-v1250-after-a-failed-upgrade">Rolling back to v1.25.0 after a failed upgrade</a></h2>
<p>v1.26.0 includes a lot of large changes. If something problematic
occurs, you may want to roll-back to a previous version of Synapse.
Because v1.26.0 also includes a new database schema version, reverting
that version is also required alongside the generic rollback
instructions mentioned above. In short, to roll back to v1.25.0 you need
to:</p>
<ol>
<li>
<p>Stop the server</p>
</li>
<li>
<p>Decrease the schema version in the database:</p>
<pre><codeclass="language-sql">UPDATE schema_version SET version = 58;
</code></pre>
</li>
<li>
<p>Delete the ignored users & chain cover data:</p>
<pre><codeclass="language-sql">DROP TABLE IF EXISTS ignored_users;
<p>This release introduces a backwards-incompatible change to modules
making use of <code>ThirdPartyEventRules</code> in Synapse. If you make use of a
module defined under the <code>third_party_event_rules</code> config option, please
make sure it is updated to handle the below change:</p>
<p>The <code>http_client</code> argument is no longer passed to modules as they are
initialised. Instead, modules are expected to make use of the
<code>http_client</code> property on the <code>ModuleApi</code> class. Modules are now passed
a <code>module_api</code> argument during initialisation, which is an instance of
<code>ModuleApi</code>. <code>ModuleApi</code> instances have a <code>http_client</code> property which
acts the same as the <code>http_client</code> argument previously passed to
<code>ThirdPartyEventRules</code> modules.</p>
<h1id="upgrading-to-v1210"><aclass="header"href="#upgrading-to-v1210">Upgrading to v1.21.0</a></h1>
<h2id="forwarding-_synapseclient-through-your-reverse-proxy"><aclass="header"href="#forwarding-_synapseclient-through-your-reverse-proxy">Forwarding <code>/_synapse/client</code> through your reverse proxy</a></h2>
<code>/_synapse/client/password_reset/{medium}/submit_token</code> with the query
parameters from the original link, presented as a URL-encoded form. See
the file itself for more details.</p>
<h2id="updated-single-sign-on-html-templates"><aclass="header"href="#updated-single-sign-on-html-templates">Updated Single Sign-on HTML Templates</a></h2>
<p>The <code>saml_error.html</code> template was removed from Synapse and replaced
with the <code>sso_error.html</code> template. If your Synapse is configured to use
SAML and a custom <code>sso_redirect_confirm_template_dir</code> configuration then
any customisations of the <code>saml_error.html</code> template will need to be
merged into the <code>sso_error.html</code> template. These templates are similar,
but the parameters are slightly different:</p>
<ul>
<li>The <code>msg</code> parameter should be renamed to <code>error_description</code>.</li>
<li>There is no longer a <code>code</code> parameter for the response code.</li>
<li>A string <code>error</code> parameter is available that includes a short hint
of why a user is seeing the error page.</li>
</ul>
<h1id="upgrading-to-v1180"><aclass="header"href="#upgrading-to-v1180">Upgrading to v1.18.0</a></h1>
<h2id="docker--py3-suffix-will-be-removed-in-future-versions"><aclass="header"href="#docker--py3-suffix-will-be-removed-in-future-versions">Docker <code>-py3</code> suffix will be removed in future versions</a></h2>
<h2id="redis-replication-is-now-recommended-in-lieu-of-tcp-replication"><aclass="header"href="#redis-replication-is-now-recommended-in-lieu-of-tcp-replication">Redis replication is now recommended in lieu of TCP replication</a></h2>
<p>When setting up worker processes, we now recommend the use of a Redis
server for replication. <strong>The old direct TCP connection method is
deprecated and will be removed in a future release.</strong> See
<h1id="upgrading-to-v1140"><aclass="header"href="#upgrading-to-v1140">Upgrading to v1.14.0</a></h1>
<p>This version includes a database update which is run as part of the
upgrade, and which may take a couple of minutes in the case of a large
server. Synapse will not respond to HTTP requests while this update is
taking place.</p>
<h1id="upgrading-to-v1130"><aclass="header"href="#upgrading-to-v1130">Upgrading to v1.13.0</a></h1>
<h2id="incorrect-database-migration-in-old-synapse-versions"><aclass="header"href="#incorrect-database-migration-in-old-synapse-versions">Incorrect database migration in old synapse versions</a></h2>
<p>A bug was introduced in Synapse 1.4.0 which could cause the room
directory to be incomplete or empty if Synapse was upgraded directly
from v1.2.1 or earlier, to versions between v1.4.0 and v1.12.x.</p>
<p>This will <em>not</em> be a problem for Synapse installations which were:</p>
<p>: - created at v1.4.0 or later,
- upgraded via v1.3.x, or
- upgraded straight from v1.2.1 or earlier to v1.13.0 or later.</p>
<p>If completeness of the room directory is a concern, installations which
<p>Plugins using the <code>complete_sso_login</code> method of
<code>synapse.module_api.ModuleApi</code> should update to using the async/await
version <code>complete_sso_login_async</code> which includes additional checks. The
non-async version is considered deprecated.</p>
<h2id="rolling-back-to-v1124-after-a-failed-upgrade"><aclass="header"href="#rolling-back-to-v1124-after-a-failed-upgrade">Rolling back to v1.12.4 after a failed upgrade</a></h2>
<p>v1.13.0 includes a lot of large changes. If something problematic
occurs, you may want to roll-back to a previous version of Synapse.
Because v1.13.0 also includes a new database schema version, reverting
that version is also required alongside the generic rollback
instructions mentioned above. In short, to roll back to v1.12.4 you need
to:</p>
<ol>
<li>
<p>Stop the server</p>
</li>
<li>
<p>Decrease the schema version in the database:</p>
<pre><codeclass="language-sql">UPDATE schema_version SET version = 57;
</code></pre>
</li>
<li>
<p>Downgrade Synapse by following the instructions for your
installation method in the "Rolling back to older versions"
section above.</p>
</li>
</ol>
<h1id="upgrading-to-v1120"><aclass="header"href="#upgrading-to-v1120">Upgrading to v1.12.0</a></h1>
<p>This version includes a database update which is run as part of the
upgrade, and which may take some time (several hours in the case of a
large server). Synapse will not respond to HTTP requests while this
update is taking place.</p>
<p>This is only likely to be a problem in the case of a server which is
participating in many rooms.</p>
<olstart="0">
<li>
<p>As with all upgrades, it is recommended that you have a recent
backup of your database which can be used for recovery in the event
of any problems.</p>
</li>
<li>
<p>As an initial check to see if you will be affected, you can try
<h4id="delegate-email-to-an-identity-server"><aclass="header"href="#delegate-email-to-an-identity-server">Delegate email to an identity server</a></h4>
<p>Some admins will wish to continue using email verification as part of
the registration process, but will not immediately have an appropriate
SMTP server at hand.</p>
<p>To this end, we will continue to support email verification delegation
via the <code>vector.im</code> and <code>matrix.org</code> identity servers for two months.
Support for delegated email verification will be disabled on Monday 2nd
December.</p>
<p>The <code>account_threepid_delegates</code> dictionary defines whether the
homeserver should delegate an external server (typically an <ahref="https://matrix.org/docs/spec/identity_service/r0.2.1">identity
server</a>) to handle
sending confirmation messages via email and SMS.</p>
<p>So to delegate email verification, in <code>homeserver.yaml</code>, set
<code>account_threepid_delegates.email</code> to the base URL of an identity
