Merge tag 'v1.4.0'

Synapse 1.4.0 (2019-10-03)
==========================

Bugfixes
--------

- Redact `client_secret` in server logs. ([\#6158](https://github.com/matrix-org/synapse/issues/6158))

Synapse 1.4.0rc2 (2019-10-02)
=============================

Bugfixes
--------

- Fix bug in background update that adds last seen information to the `devices` table, and improve its performance on Postgres. ([\#6135](https://github.com/matrix-org/synapse/issues/6135))
- Fix bad performance of censoring redactions background task. ([\#6141](https://github.com/matrix-org/synapse/issues/6141))
- Fix fetching censored redactions from DB, which caused APIs like initial sync to fail if it tried to include the censored redaction. ([\#6145](https://github.com/matrix-org/synapse/issues/6145))
- Fix exceptions when storing large retry intervals for down remote servers. ([\#6146](https://github.com/matrix-org/synapse/issues/6146))

Internal Changes
----------------

- Fix up sample config entry for `redaction_retention_period` option. ([\#6117](https://github.com/matrix-org/synapse/issues/6117))

Synapse 1.4.0rc1 (2019-09-26)
=============================

Note that this release includes significant changes around 3pid
verification. Administrators are reminded to review the [upgrade notes](UPGRADE.rst#upgrading-to-v140).

Features
--------

- Changes to 3pid verification:
  - Add the ability to send registration emails from the homeserver rather than delegating to an identity server. ([\#5835](https://github.com/matrix-org/synapse/issues/5835), [\#5940](https://github.com/matrix-org/synapse/issues/5940), [\#5993](https://github.com/matrix-org/synapse/issues/5993), [\#5994](https://github.com/matrix-org/synapse/issues/5994), [\#5868](https://github.com/matrix-org/synapse/issues/5868))
  - Replace `trust_identity_server_for_password_resets` config option with `account_threepid_delegates`, and make the `id_server` parameteter optional on `*/requestToken` endpoints, as per [MSC2263](https://github.com/matrix-org/matrix-doc/pull/2263). ([\#5876](https://github.com/matrix-org/synapse/issues/5876), [\#5969](https://github.com/matrix-org/synapse/issues/5969), [\#6028](https://github.com/matrix-org/synapse/issues/6028))
  - Switch to using the v2 Identity Service `/lookup` API where available, with fallback to v1. (Implements [MSC2134](https://github.com/matrix-org/matrix-doc/pull/2134) plus `id_access_token authentication` for v2 Identity Service APIs from [MSC2140](https://github.com/matrix-org/matrix-doc/pull/2140)). ([\#5897](https://github.com/matrix-org/synapse/issues/5897))
  - Remove `bind_email` and `bind_msisdn` parameters from `/register` ala [MSC2140](https://github.com/matrix-org/matrix-doc/pull/2140). ([\#5964](https://github.com/matrix-org/synapse/issues/5964))
  - Add `m.id_access_token` to `unstable_features` in `/versions` as per [MSC2264](https://github.com/matrix-org/matrix-doc/pull/2264). ([\#5974](https://github.com/matrix-org/synapse/issues/5974))
  - Use the v2 Identity Service API for 3PID invites. ([\#5979](https://github.com/matrix-org/synapse/issues/5979))
  - Add `POST /_matrix/client/unstable/account/3pid/unbind` endpoint from [MSC2140](https://github.com/matrix-org/matrix-doc/pull/2140) for unbinding a 3PID from an identity server without removing it from the homeserver user account. ([\#5980](https://github.com/matrix-org/synapse/issues/5980), [\#6062](https://github.com/matrix-org/synapse/issues/6062))
  - Use `account_threepid_delegate.email` and `account_threepid_delegate.msisdn` for validating threepid sessions. ([\#6011](https://github.com/matrix-org/synapse/issues/6011))
  - Allow homeserver to handle or delegate email validation when adding an email to a user's account. ([\#6042](https://github.com/matrix-org/synapse/issues/6042))
  - Implement new Client Server API endpoints `/account/3pid/add` and `/account/3pid/bind` as per [MSC2290](https://github.com/matrix-org/matrix-doc/pull/2290). ([\#6043](https://github.com/matrix-org/synapse/issues/6043))
  - Add an unstable feature flag for separate add/bind 3pid APIs. ([\#6044](https://github.com/matrix-org/synapse/issues/6044))
  - Remove `bind` parameter from Client Server POST `/account` endpoint as per [MSC2290](https://github.com/matrix-org/matrix-doc/pull/2290/). ([\#6067](https://github.com/matrix-org/synapse/issues/6067))
  - Add `POST /add_threepid/msisdn/submit_token` endpoint for proxying submitToken on an `account_threepid_handler`. ([\#6078](https://github.com/matrix-org/synapse/issues/6078))
  - Add `submit_url` response parameter to `*/msisdn/requestToken` endpoints. ([\#6079](https://github.com/matrix-org/synapse/issues/6079))
  - Add `m.require_identity_server` flag to /version's unstable_features. ([\#5972](https://github.com/matrix-org/synapse/issues/5972))
- Enhancements to OpenTracing support:
  - Make OpenTracing work in worker mode. ([\#5771](https://github.com/matrix-org/synapse/issues/5771))
  - Pass OpenTracing contexts between servers when transmitting EDUs. ([\#5852](https://github.com/matrix-org/synapse/issues/5852))
  - OpenTracing for device list updates. ([\#5853](https://github.com/matrix-org/synapse/issues/5853))
  - Add a tag recording a request's authenticated entity and corresponding servlet in OpenTracing. ([\#5856](https://github.com/matrix-org/synapse/issues/5856))
  - Add minimum OpenTracing for client servlets. ([\#5983](https://github.com/matrix-org/synapse/issues/5983))
  - Check at setup that OpenTracing is installed if it's enabled in the config. ([\#5985](https://github.com/matrix-org/synapse/issues/5985))
  - Trace replication send times. ([\#5986](https://github.com/matrix-org/synapse/issues/5986))
  - Include missing OpenTracing contexts in outbout replication requests. ([\#5982](https://github.com/matrix-org/synapse/issues/5982))
  - Fix sending of EDUs when OpenTracing is enabled with an empty whitelist. ([\#5984](https://github.com/matrix-org/synapse/issues/5984))
  - Fix invalid references to None while OpenTracing if the log context slips. ([\#5988](https://github.com/matrix-org/synapse/issues/5988), [\#5991](https://github.com/matrix-org/synapse/issues/5991))
  - OpenTracing for room and e2e keys. ([\#5855](https://github.com/matrix-org/synapse/issues/5855))
  - Add OpenTracing span over HTTP push processing. ([\#6003](https://github.com/matrix-org/synapse/issues/6003))
- Add an admin API to purge old rooms from the database. ([\#5845](https://github.com/matrix-org/synapse/issues/5845))
- Retry well-known lookups if we have recently seen a valid well-known record for the server. ([\#5850](https://github.com/matrix-org/synapse/issues/5850))
- Add support for filtered room-directory search requests over federation ([MSC2197](https://github.com/matrix-org/matrix-doc/pull/2197), in order to allow upcoming room directory query performance improvements. ([\#5859](https://github.com/matrix-org/synapse/issues/5859))
- Correctly retry all hosts returned from SRV when we fail to connect. ([\#5864](https://github.com/matrix-org/synapse/issues/5864))
- Add admin API endpoint for setting whether or not a user is a server administrator. ([\#5878](https://github.com/matrix-org/synapse/issues/5878))
- Enable cleaning up extremities with dummy events by default to prevent undue build up of forward extremities. ([\#5884](https://github.com/matrix-org/synapse/issues/5884))
- Add config option to sign remote key query responses with a separate key. ([\#5895](https://github.com/matrix-org/synapse/issues/5895))
- Add support for config templating. ([\#5900](https://github.com/matrix-org/synapse/issues/5900))
- Users with the type of "support" or "bot" are no longer required to consent. ([\#5902](https://github.com/matrix-org/synapse/issues/5902))
- Let synctl accept a directory of config files. ([\#5904](https://github.com/matrix-org/synapse/issues/5904))
- Increase max display name size to 256. ([\#5906](https://github.com/matrix-org/synapse/issues/5906))
- Add admin API endpoint for getting whether or not a user is a server administrator. ([\#5914](https://github.com/matrix-org/synapse/issues/5914))
- Redact events in the database that have been redacted for a week. ([\#5934](https://github.com/matrix-org/synapse/issues/5934))
- New prometheus metrics:
  - `synapse_federation_known_servers`: represents the total number of servers your server knows about (i.e. is in rooms with), including itself. Enable by setting `metrics_flags.known_servers` to True in the configuration.([\#5981](https://github.com/matrix-org/synapse/issues/5981))
  - `synapse_build_info`: exposes the Python version, OS version, and Synapse version of the running server. ([\#6005](https://github.com/matrix-org/synapse/issues/6005))
- Give appropriate exit codes when synctl fails. ([\#5992](https://github.com/matrix-org/synapse/issues/5992))
- Apply the federation blacklist to requests to identity servers. ([\#6000](https://github.com/matrix-org/synapse/issues/6000))
- Add `report_stats_endpoint` option to configure where stats are reported to, if enabled. Contributed by @Sorunome. ([\#6012](https://github.com/matrix-org/synapse/issues/6012))
- Add config option to increase ratelimits for room admins redacting messages. ([\#6015](https://github.com/matrix-org/synapse/issues/6015))
- Stop sending federation transactions to servers which have been down for a long time. ([\#6026](https://github.com/matrix-org/synapse/issues/6026))
- Make the process for mapping SAML2 users to matrix IDs more flexible. ([\#6037](https://github.com/matrix-org/synapse/issues/6037))
- Return a clearer error message when a timeout occurs when attempting to contact an identity server. ([\#6073](https://github.com/matrix-org/synapse/issues/6073))
- Prevent password reset's submit_token endpoint from accepting trailing slashes. ([\#6074](https://github.com/matrix-org/synapse/issues/6074))
- Return 403 on `/register/available` if registration has been disabled. ([\#6082](https://github.com/matrix-org/synapse/issues/6082))
- Explicitly log when a homeserver does not have the `trusted_key_servers` config field configured. ([\#6090](https://github.com/matrix-org/synapse/issues/6090))
- Add support for pruning old rows in `user_ips` table. ([\#6098](https://github.com/matrix-org/synapse/issues/6098))

Bugfixes
--------

- Don't create broken room when `power_level_content_override.users` does not contain `creator_id`. ([\#5633](https://github.com/matrix-org/synapse/issues/5633))
- Fix database index so that different backup versions can have the same sessions. ([\#5857](https://github.com/matrix-org/synapse/issues/5857))
- Fix Synapse looking for config options `password_reset_failure_template` and `password_reset_success_template`, when they are actually `password_reset_template_failure_html`, `password_reset_template_success_html`. ([\#5863](https://github.com/matrix-org/synapse/issues/5863))
- Fix stack overflow when recovering an appservice which had an outage. ([\#5885](https://github.com/matrix-org/synapse/issues/5885))
- Fix error message which referred to `public_base_url` instead of `public_baseurl`. Thanks to @aaronraimist for the fix! ([\#5909](https://github.com/matrix-org/synapse/issues/5909))
- Fix 404 for thumbnail download when `dynamic_thumbnails` is `false` and the thumbnail was dynamically generated. Fix reported by rkfg. ([\#5915](https://github.com/matrix-org/synapse/issues/5915))
- Fix a cache-invalidation bug for worker-based deployments. ([\#5920](https://github.com/matrix-org/synapse/issues/5920))
- Fix admin API for listing media in a room not being available with an external media repo. ([\#5966](https://github.com/matrix-org/synapse/issues/5966))
- Fix list media admin API always returning an error. ([\#5967](https://github.com/matrix-org/synapse/issues/5967))
- Fix room and user stats tracking. ([\#5971](https://github.com/matrix-org/synapse/issues/5971), [\#5998](https://github.com/matrix-org/synapse/issues/5998), [\#6029](https://github.com/matrix-org/synapse/issues/6029))
- Return a `M_MISSING_PARAM` if `sid` is not provided to `/account/3pid`. ([\#5995](https://github.com/matrix-org/synapse/issues/5995))
- `federation_certificate_verification_whitelist` now will not cause `TypeErrors` to be raised (a regression in 1.3). Additionally, it now supports internationalised domain names in their non-canonical representation. ([\#5996](https://github.com/matrix-org/synapse/issues/5996))
- Only count real users when checking for auto-creation of auto-join room. ([\#6004](https://github.com/matrix-org/synapse/issues/6004))
- Ensure support users can be registered even if MAU limit is reached. ([\#6020](https://github.com/matrix-org/synapse/issues/6020))
- Fix bug where login error was shown incorrectly on SSO fallback login. ([\#6024](https://github.com/matrix-org/synapse/issues/6024))
- Fix bug in calculating the federation retry backoff period. ([\#6025](https://github.com/matrix-org/synapse/issues/6025))
- Prevent exceptions being logged when extremity-cleanup events fail due to lack of user consent to the terms of service. ([\#6053](https://github.com/matrix-org/synapse/issues/6053))
- Remove POST method from password-reset `submit_token` endpoint until we implement `submit_url` functionality. ([\#6056](https://github.com/matrix-org/synapse/issues/6056))
- Fix logcontext spam on non-Linux platforms. ([\#6059](https://github.com/matrix-org/synapse/issues/6059))
- Ensure query parameters in email validation links are URL-encoded. ([\#6063](https://github.com/matrix-org/synapse/issues/6063))
- Fix a bug which caused SAML attribute maps to be overridden by defaults. ([\#6069](https://github.com/matrix-org/synapse/issues/6069))
- Fix the logged number of updated items for the `users_set_deactivated_flag` background update. ([\#6092](https://github.com/matrix-org/synapse/issues/6092))
- Add `sid` to `next_link` for email validation. ([\#6097](https://github.com/matrix-org/synapse/issues/6097))
- Threepid validity checks on msisdns should not be dependent on `threepid_behaviour_email`. ([\#6104](https://github.com/matrix-org/synapse/issues/6104))
- Ensure that servers which are not configured to support email address verification do not offer it in the registration flows. ([\#6107](https://github.com/matrix-org/synapse/issues/6107))

Updates to the Docker image
---------------------------

- Avoid changing `UID/GID` if they are already correct. ([\#5970](https://github.com/matrix-org/synapse/issues/5970))
- Provide `SYNAPSE_WORKER` envvar to specify python module. ([\#6058](https://github.com/matrix-org/synapse/issues/6058))

Improved Documentation
----------------------

- Convert documentation to markdown (from rst) ([\#5849](https://github.com/matrix-org/synapse/issues/5849))
- Update `INSTALL.md` to say that Python 2 is no longer supported. ([\#5953](https://github.com/matrix-org/synapse/issues/5953))
- Add developer documentation for using SAML2. ([\#6032](https://github.com/matrix-org/synapse/issues/6032))
- Add some notes on rolling back to v1.3.1. ([\#6049](https://github.com/matrix-org/synapse/issues/6049))
- Update the upgrade notes. ([\#6050](https://github.com/matrix-org/synapse/issues/6050))

Deprecations and Removals
-------------------------

- Remove shared-secret registration from `/_matrix/client/r0/register` endpoint. Contributed by Awesome Technologies Innovationslabor GmbH. ([\#5877](https://github.com/matrix-org/synapse/issues/5877))
- Deprecate the `trusted_third_party_id_servers` option. ([\#5875](https://github.com/matrix-org/synapse/issues/5875))

Internal Changes
----------------

- Lay the groundwork for structured logging output. ([\#5680](https://github.com/matrix-org/synapse/issues/5680))
- Retry well-known lookup before the cache expires, giving a grace period where the remote well-known can be down but we still use the old result. ([\#5844](https://github.com/matrix-org/synapse/issues/5844))
- Remove log line for debugging issue #5407. ([\#5860](https://github.com/matrix-org/synapse/issues/5860))
- Refactor the Appservice scheduler code. ([\#5886](https://github.com/matrix-org/synapse/issues/5886))
- Compatibility with v2 Identity Service APIs other than /lookup. ([\#5892](https://github.com/matrix-org/synapse/issues/5892), [\#6013](https://github.com/matrix-org/synapse/issues/6013))
- Stop populating some unused tables. ([\#5893](https://github.com/matrix-org/synapse/issues/5893), [\#6047](https://github.com/matrix-org/synapse/issues/6047))
- Add missing index on `users_in_public_rooms` to improve the performance of directory queries. ([\#5894](https://github.com/matrix-org/synapse/issues/5894))
- Improve the logging when we have an error when fetching signing keys. ([\#5896](https://github.com/matrix-org/synapse/issues/5896))
- Add support for database engine-specific schema deltas, based on file extension. ([\#5911](https://github.com/matrix-org/synapse/issues/5911))
- Update Buildkite pipeline to use plugins instead of buildkite-agent commands. ([\#5922](https://github.com/matrix-org/synapse/issues/5922))
- Add link in sample config to the logging config schema. ([\#5926](https://github.com/matrix-org/synapse/issues/5926))
- Remove unnecessary parentheses in return statements. ([\#5931](https://github.com/matrix-org/synapse/issues/5931))
- Remove unused `jenkins/prepare_sytest.sh` file. ([\#5938](https://github.com/matrix-org/synapse/issues/5938))
- Move Buildkite pipeline config to the pipelines repo. ([\#5943](https://github.com/matrix-org/synapse/issues/5943))
- Remove unnecessary return statements in the codebase which were the result of a regex run. ([\#5962](https://github.com/matrix-org/synapse/issues/5962))
- Remove left-over methods from v1 registration API. ([\#5963](https://github.com/matrix-org/synapse/issues/5963))
- Cleanup event auth type initialisation. ([\#5975](https://github.com/matrix-org/synapse/issues/5975))
- Clean up dependency checking at setup. ([\#5989](https://github.com/matrix-org/synapse/issues/5989))
- Update OpenTracing docs to use the unified `trace` method. ([\#5776](https://github.com/matrix-org/synapse/issues/5776))
- Small refactor of function arguments and docstrings in` RoomMemberHandler`. ([\#6009](https://github.com/matrix-org/synapse/issues/6009))
- Remove unused `origin` argument on `FederationHandler.add_display_name_to_third_party_invite`. ([\#6010](https://github.com/matrix-org/synapse/issues/6010))
- Add a `failure_ts` column to the `destinations` database table. ([\#6016](https://github.com/matrix-org/synapse/issues/6016), [\#6072](https://github.com/matrix-org/synapse/issues/6072))
- Clean up some code in the retry logic. ([\#6017](https://github.com/matrix-org/synapse/issues/6017))
- Fix the structured logging tests stomping on the global log configuration for subsequent tests. ([\#6023](https://github.com/matrix-org/synapse/issues/6023))
- Clean up the sample config for SAML authentication. ([\#6064](https://github.com/matrix-org/synapse/issues/6064))
- Change mailer logging to reflect Synapse doesn't just do chat notifications by email now. ([\#6075](https://github.com/matrix-org/synapse/issues/6075))
- Move last-seen info into devices table. ([\#6089](https://github.com/matrix-org/synapse/issues/6089))
- Remove unused parameter to `get_user_id_by_threepid`. ([\#6099](https://github.com/matrix-org/synapse/issues/6099))
- Refactor the user-interactive auth handling. ([\#6105](https://github.com/matrix-org/synapse/issues/6105))
- Refactor code for calculating registration flows. ([\#6106](https://github.com/matrix-org/synapse/issues/6106))

1 files changed, 251 insertions, 28 deletions

diff --git a/UPGRADE.rst b/UPGRADE.rst
index cf228c7c52..9562114d59 100644
--- a/UPGRADE.rst
+++ b/UPGRADE.rst
@@ -2,58 +2,268 @@ Upgrading Synapse
 =================
 
 Before upgrading check if any special steps are required to upgrade from the
-what you currently have installed to current version of synapse. The extra
+what you currently have installed to current version of Synapse. The extra
 instructions that may be required are listed later in this document.
 
-1. If synapse was installed in a virtualenv then activate that virtualenv before
-   upgrading. If synapse is installed in a virtualenv in ``~/synapse/env`` then
-   run:
+* If Synapse was installed using `prebuilt packages
+  <INSTALL.md#prebuilt-packages>`_, you will need to follow the normal process
+  for upgrading those packages.
 
-   .. code:: bash
+* If Synapse was installed from source, then:
 
-       source ~/synapse/env/bin/activate
-
-2. If synapse was installed using pip then upgrade to the latest version by
-   running:
+  1. Activate the virtualenv before upgrading. For example, if Synapse is
+     installed in a virtualenv in ``~/synapse/env`` then run:
 
-   .. code:: bash
+     .. code:: bash
 
-       pip install --upgrade matrix-synapse[all]
+       source ~/synapse/env/bin/activate
 
-       # restart synapse
-       synctl restart
+  2. If Synapse was installed using pip then upgrade to the latest version by
+     running:
 
+     .. code:: bash
 
-   If synapse was installed using git then upgrade to the latest version by
-   running:
+       pip install --upgrade matrix-synapse
 
-   .. code:: bash
+     If Synapse was installed using git then upgrade to the latest version by
+     running:
 
-       # Pull the latest version of the master branch.
+     .. code:: bash
+     
        git pull
+       pip install --upgrade .
 
-       # Update synapse and its python dependencies.
-       pip install --upgrade .[all]
+  3. Restart Synapse:
 
-       # restart synapse
-       ./synctl restart
+     .. code:: bash
 
+       ./synctl restart
 
-To check whether your update was successful, you can check the Server header
-returned by the Client-Server API:
+To check whether your update was successful, you can check the running server
+version with:
 
 .. code:: bash
 
-    # replace <host.name> with the hostname of your synapse homeserver.
-    # You may need to specify a port (eg, :8448) if your server is not
-    # configured on port 443.
-    curl -kv https://<host.name>/_matrix/client/versions 2>&1 | grep "Server:"
+    # you may need to replace 'localhost:8008' if synapse is not configured
+    # to listen on port 8008.
+
+    curl http://localhost:8008/_synapse/admin/v1/server_version
+
+Rolling back to older versions
+------------------------------
+
+Rolling back to previous releases can be difficult, due to database schema
+changes between releases. Where we have been able to test the rollback process,
+this will be noted below.
+
+In general, you will need to undo any changes made during the upgrade process,
+for example:
+
+* pip:
+
+  .. code:: bash
+
+     source env/bin/activate
+     # replace `1.3.0` accordingly:
+     pip install matrix-synapse==1.3.0
+
+* Debian:
+
+  .. code:: bash
+
+     # replace `1.3.0` and `stretch` accordingly:
+     wget https://packages.matrix.org/debian/pool/main/m/matrix-synapse-py3/matrix-synapse-py3_1.3.0+stretch1_amd64.deb
+     dpkg -i matrix-synapse-py3_1.3.0+stretch1_amd64.deb
+
+Upgrading to v1.4.0
+===================
+
+New custom templates
+--------------------
+
+If you have configured a custom template directory with the
+``email.template_dir`` option, be aware that there are new templates regarding
+registration and threepid management (see below) that must be included.
+
+* ``registration.html`` and ``registration.txt``
+* ``registration_success.html`` and ``registration_failure.html``
+* ``add_threepid.html`` and  ``add_threepid.txt``
+* ``add_threepid_failure.html`` and ``add_threepid_success.html``
+
+Synapse will expect these files to exist inside the configured template
+directory, and **will fail to start** if they are absent.
+To view the default templates, see `synapse/res/templates
+<https://github.com/matrix-org/synapse/tree/master/synapse/res/templates>`_.
+
+3pid verification changes
+-------------------------
+
+**Note: As of this release, users will be unable to add phone numbers or email
+addresses to their accounts, without changes to the Synapse configuration. This
+includes adding an email address during registration.**
+
+It is possible for a user to associate an email address or phone number
+with their account, for a number of reasons:
+
+* for use when logging in, as an alternative to the user id.
+* in the case of email, as an alternative contact to help with account recovery.
+* in the case of email, to receive notifications of missed messages.
+
+Before an email address or phone number can be added to a user's account,
+or before such an address is used to carry out a password-reset, Synapse must
+confirm the operation with the owner of the email address or phone number.
+It does this by sending an email or text giving the user a link or token to confirm
+receipt. This process is known as '3pid verification'. ('3pid', or 'threepid',
+stands for third-party identifier, and we use it to refer to external
+identifiers such as email addresses and phone numbers.)
+
+Previous versions of Synapse delegated the task of 3pid verification to an
+identity server by default. In most cases this server is ``vector.im`` or
+``matrix.org``.
+
+In Synapse 1.4.0, for security and privacy reasons, the homeserver will no
+longer delegate this task to an identity server by default. Instead,
+the server administrator will need to explicitly decide how they would like the
+verification messages to be sent.
+
+In the medium term, the ``vector.im`` and ``matrix.org`` identity servers will
+disable support for delegated 3pid verification entirely. However, in order to
+ease the transition, they will retain the capability for a limited
+period. Delegated email verification will be disabled on Monday 2nd December
+2019 (giving roughly 2 months notice). Disabling delegated SMS verification
+will follow some time after that once SMS verification support lands in
+Synapse.
+
+Once delegated 3pid verification support has been disabled in the ``vector.im`` and
+``matrix.org`` identity servers, all Synapse versions that depend on those
+instances will be unable to verify email and phone numbers through them. There
+are no imminent plans to remove delegated 3pid verification from Sydent
+generally. (Sydent is the identity server project that backs the ``vector.im`` and
+``matrix.org`` instances).
+
+Email
+~~~~~
+Following upgrade, to continue verifying email (e.g. as part of the
+registration process), admins can either:-
+
+* Configure Synapse to use an email server.
+* Run or choose an identity server which allows delegated email verification
+  and delegate to it.
+
+Configure SMTP in Synapse
++++++++++++++++++++++++++
+
+To configure an SMTP server for Synapse, modify the configuration section
+headed ``email``, and be sure to have at least the ``smtp_host, smtp_port``
+and ``notif_from`` fields filled out.
+
+You may also need to set ``smtp_user``, ``smtp_pass``, and
+``require_transport_security``.
+
+See the `sample configuration file <docs/sample_config.yaml>`_ for more details
+on these settings.
+
+Delegate email to an identity server
+++++++++++++++++++++++++++++++++++++
+
+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.
+
+To this end, we will continue to support email verification delegation via the
+``vector.im`` and ``matrix.org`` identity servers for two months. Support for
+delegated email verification will be disabled on Monday 2nd December.
+
+The ``account_threepid_delegates`` dictionary defines whether the homeserver
+should delegate an external server (typically an `identity server
+<https://matrix.org/docs/spec/identity_service/r0.2.1>`_) to handle sending
+confirmation messages via email and SMS.
+
+So to delegate email verification, in ``homeserver.yaml``, set
+``account_threepid_delegates.email`` to the base URL of an identity server. For
+example:
+
+.. code:: yaml
+
+   account_threepid_delegates:
+       email: https://example.com     # Delegate email sending to example.com
+
+Note that ``account_threepid_delegates.email`` replaces the deprecated
+``email.trust_identity_server_for_password_resets``: if
+``email.trust_identity_server_for_password_resets`` is set to ``true``, and
+``account_threepid_delegates.email`` is not set, then the first entry in
+``trusted_third_party_id_servers`` will be used as the
+``account_threepid_delegate`` for email. This is to ensure compatibility with
+existing Synapse installs that set up external server handling for these tasks
+before v1.4.0. If ``email.trust_identity_server_for_password_resets`` is
+``true`` and no trusted identity server domains are configured, Synapse will
+report an error and refuse to start.
+
+If ``email.trust_identity_server_for_password_resets`` is ``false`` or absent
+and no ``email`` delegate is configured in ``account_threepid_delegates``,
+then Synapse will send email verification messages itself, using the configured
+SMTP server (see above).
+that type.
+
+Phone numbers
+~~~~~~~~~~~~~
+
+Synapse does not support phone-number verification itself, so the only way to
+maintain the ability for users to add phone numbers to their accounts will be
+by continuing to delegate phone number verification to the ``matrix.org`` and
+``vector.im`` identity servers (or another identity server that supports SMS
+sending).
+
+The ``account_threepid_delegates`` dictionary defines whether the homeserver
+should delegate an external server (typically an `identity server
+<https://matrix.org/docs/spec/identity_service/r0.2.1>`_) to handle sending
+confirmation messages via email and SMS.
+
+So to delegate phone number verification, in ``homeserver.yaml``, set
+``account_threepid_delegates.msisdn`` to the base URL of an identity
+server. For example:
+
+.. code:: yaml
+
+   account_threepid_delegates:
+       msisdn: https://example.com     # Delegate sms sending to example.com
+
+The ``matrix.org`` and ``vector.im`` identity servers will continue to support
+delegated phone number verification via SMS until such time as it is possible
+for admins to configure their servers to perform phone number verification
+directly. More details will follow in a future release.
+
+Rolling back to v1.3.1
+----------------------
+
+If you encounter problems with v1.4.0, it should be possible to roll back to
+v1.3.1, subject to the following:
+
+* The 'room statistics' engine was heavily reworked in this release (see
+  `#5971 <https://github.com/matrix-org/synapse/pull/5971>`_), including
+  significant changes to the database schema, which are not easily
+  reverted. This will cause the room statistics engine to stop updating when
+  you downgrade.
+
+  The room statistics are essentially unused in v1.3.1 (in future versions of
+  Synapse, they will be used to populate the room directory), so there should
+  be no loss of functionality. However, the statistics engine will write errors
+  to the logs, which can be avoided by setting the following in
+  `homeserver.yaml`:
+
+  .. code:: yaml
+
+    stats:
+      enabled: false
+
+  Don't forget to re-enable it when you upgrade again, in preparation for its
+  use in the room directory!
 
 Upgrading to v1.2.0
 ===================
 
 Some counter metrics have been renamed, with the old names deprecated. See
-`the metrics documentation <docs/metrics-howto.rst#renaming-of-metrics--deprecation-of-old-names-in-12>`_
+`the metrics documentation <docs/metrics-howto.md#renaming-of-metrics--deprecation-of-old-names-in-12>`_
 for details.
 
 Upgrading to v1.1.0
@@ -132,6 +342,19 @@ server for password resets, set ``trust_identity_server_for_password_resets`` to
 See the `sample configuration file <docs/sample_config.yaml>`_
 for more details on these settings.
 
+New email templates
+---------------
+Some new templates have been added to the default template directory for the purpose of the
+homeserver sending its own password reset emails. If you have configured a custom
+``template_dir`` in your Synapse config, these files will need to be added.
+
+``password_reset.html`` and ``password_reset.txt`` are HTML and plain text templates
+respectively that contain the contents of what will be emailed to the user upon attempting to
+reset their password via email. ``password_reset_success.html`` and
+``password_reset_failure.html`` are HTML files that the content of which (assuming no redirect
+URL is set) will be shown to the user after they attempt to click the link in the email sent
+to them.
+
 Upgrading to v0.99.0
 ====================