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  • The deprecation of the old endpoints was announced with Synapse 1.20.0
    (released on 2020-09-22) and makes it easier for homeserver admins to
    lock down external access to the Admin API endpoints.
    
    # Upgrading to v1.23.0
    
    ## Structured logging configuration breaking changes
    
    This release deprecates use of the `structured: true` logging
    configuration for structured logging. If your logging configuration
    contains `structured: true` then it should be modified based on the
    
    [structured logging documentation](https://matrix-org.github.io/synapse/v1.56/structured_logging.html#upgrading-from-legacy-structured-logging-configuration).
    
    
    The `structured` and `drains` logging options are now deprecated and
    should be replaced by standard logging configuration of `handlers` and
    `formatters`.
    
    A future will release of Synapse will make using `structured: true` an
    error.
    
    # Upgrading to v1.22.0
    
    ## ThirdPartyEventRules breaking changes
    
    This release introduces a backwards-incompatible change to modules
    making use of `ThirdPartyEventRules` in Synapse. If you make use of a
    module defined under the `third_party_event_rules` config option, please
    make sure it is updated to handle the below change:
    
    The `http_client` argument is no longer passed to modules as they are
    initialised. Instead, modules are expected to make use of the
    `http_client` property on the `ModuleApi` class. Modules are now passed
    a `module_api` argument during initialisation, which is an instance of
    `ModuleApi`. `ModuleApi` instances have a `http_client` property which
    acts the same as the `http_client` argument previously passed to
    `ThirdPartyEventRules` modules.
    
    # Upgrading to v1.21.0
    
    ## Forwarding `/_synapse/client` through your reverse proxy
    
    
    The [reverse proxy documentation](reverse_proxy.md)
    
    has been updated to include reverse proxy directives for
    `/_synapse/client/*` endpoints. As the user password reset flow now uses
    endpoints under this prefix, **you must update your reverse proxy
    configurations for user password reset to work**.
    
    
    Additionally, note that the [Synapse worker documentation](workers.md) has been updated to
    
    
    :   state that the `/_synapse/client/password_reset/email/submit_token`
        endpoint can be handled
    
    by all workers. If you make use of Synapse's worker feature, please
    update your reverse proxy configuration to reflect this change.
    
    ## New HTML templates
    
    A new HTML template,
    [password_reset_confirmation.html](https://github.com/matrix-org/synapse/blob/develop/synapse/res/templates/password_reset_confirmation.html),
    has been added to the `synapse/res/templates` directory. If you are
    using a custom template directory, you may want to copy the template
    over and modify it.
    
    Note that as of v1.20.0, templates do not need to be included in custom
    template directories for Synapse to start. The default templates will be
    used if a custom template cannot be found.
    
    This page will appear to the user after clicking a password reset link
    that has been emailed to them.
    
    To complete password reset, the page must include a way to make a
    
    `/_synapse/client/password_reset/{medium}/submit_token` with the query
    parameters from the original link, presented as a URL-encoded form. See
    the file itself for more details.
    
    ## Updated Single Sign-on HTML Templates
    
    The `saml_error.html` template was removed from Synapse and replaced
    with the `sso_error.html` template. If your Synapse is configured to use
    SAML and a custom `sso_redirect_confirm_template_dir` configuration then
    any customisations of the `saml_error.html` template will need to be
    merged into the `sso_error.html` template. These templates are similar,
    but the parameters are slightly different:
    
    -   The `msg` parameter should be renamed to `error_description`.
    -   There is no longer a `code` parameter for the response code.
    -   A string `error` parameter is available that includes a short hint
        of why a user is seeing the error page.
    
    # Upgrading to v1.18.0
    
    
    ## Docker `-py3` suffix will be removed in future versions
    
    
    From 10th August 2020, we will no longer publish Docker images with the
    
    `-py3` tag suffix. The images tagged with the
    `-py3` suffix have been identical to the non-suffixed tags
    
    since release 0.99.0, and the suffix is obsolete.
    
    
    On 10th August, we will remove the `latest-py3` tag.
    Existing per-release tags (such as `v1.18.0-py3` will not
    be removed, but no new `-py3` tags will be added.
    
    Scripts relying on the `-py3` suffix will need to be
    
    updated.
    
    ## Redis replication is now recommended in lieu of TCP replication
    
    When setting up worker processes, we now recommend the use of a Redis
    server for replication. **The old direct TCP connection method is
    deprecated and will be removed in a future release.** See
    
    [workers](workers.md) for more details.
    
    
    # Upgrading to v1.14.0
    
    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.
    
    # Upgrading to v1.13.0
    
    ## Incorrect database migration in old synapse versions
    
    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.
    
    This will *not* be a problem for Synapse installations which were:
    
    :   -   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.
    
    If completeness of the room directory is a concern, installations which
    are affected can be repaired as follows:
    
    
    1.  Run the following sql from a `psql` or
        `sqlite3` console:
    
    
        ```sql
        INSERT INTO background_updates (update_name, progress_json, depends_on) VALUES
           ('populate_stats_process_rooms', '{}', 'current_state_events_membership');
    
        INSERT INTO background_updates (update_name, progress_json, depends_on) VALUES
           ('populate_stats_process_users', '{}', 'populate_stats_process_rooms');
        ```
    
    2.  Restart synapse.
    
    ## New Single Sign-on HTML Templates
    
    New templates (`sso_auth_confirm.html`, `sso_auth_success.html`, and
    `sso_account_deactivated.html`) were added to Synapse. If your Synapse
    is configured to use SSO and a custom
    `sso_redirect_confirm_template_dir` configuration then these templates
    will need to be copied from
    [synapse/res/templates](synapse/res/templates) into that directory.
    
    ## Synapse SSO Plugins Method Deprecation
    
    Plugins using the `complete_sso_login` method of
    `synapse.module_api.ModuleApi` should update to using the async/await
    version `complete_sso_login_async` which includes additional checks. The
    non-async version is considered deprecated.
    
    ## Rolling back to v1.12.4 after a failed upgrade
    
    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:
    
    1.  Stop the server
    
    2.  Decrease the schema version in the database:
    
        ```sql
        UPDATE schema_version SET version = 57;
        ```
    
    3.  Downgrade Synapse by following the instructions for your
        installation method in the "Rolling back to older versions"
        section above.
    
    # Upgrading to v1.12.0
    
    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.
    
    This is only likely to be a problem in the case of a server which is
    participating in many rooms.
    
    0.  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.
    
    1.  As an initial check to see if you will be affected, you can try
    
        running the following query from the `psql` or
        `sqlite3` console. It is safe to run it while Synapse is
    
        still running.
    
        ```sql
        SELECT MAX(q.v) FROM (
          SELECT (
            SELECT ej.json AS v
            FROM state_events se INNER JOIN event_json ej USING (event_id)
            WHERE se.room_id=rooms.room_id AND se.type='m.room.create' AND se.state_key=''
            LIMIT 1
          ) FROM rooms WHERE rooms.room_version IS NULL
        ) q;
        ```
    
        This query will take about the same amount of time as the upgrade
        process: ie, if it takes 5 minutes, then it is likely that Synapse
        will be unresponsive for 5 minutes during the upgrade.
    
        If you consider an outage of this duration to be acceptable, no
        further action is necessary and you can simply start Synapse 1.12.0.
    
        If you would prefer to reduce the downtime, continue with the steps
        below.
    
    2.  The easiest workaround for this issue is to manually create a new
        index before upgrading. On PostgreSQL, his can be done as follows:
    
        ```sql
        CREATE INDEX CONCURRENTLY tmp_upgrade_1_12_0_index
        ON state_events(room_id) WHERE type = 'm.room.create';
        ```
    
        The above query may take some time, but is also safe to run while
        Synapse is running.
    
        We assume that no SQLite users have databases large enough to be
        affected. If you *are* affected, you can run a similar query,
        omitting the `CONCURRENTLY` keyword. Note however that this
        operation may in itself cause Synapse to stop running for some time.
        Synapse admins are reminded that [SQLite is not recommended for use
    
        outside a test environment](postgres.md).
    
    
    3.  Once the index has been created, the `SELECT` query in step 1 above
        should complete quickly. It is therefore safe to upgrade to Synapse
        1.12.0.
    
    4.  Once Synapse 1.12.0 has successfully started and is responding to
        HTTP requests, the temporary index can be removed:
    
        ```sql
        DROP INDEX tmp_upgrade_1_12_0_index;
        ```
    
    # Upgrading to v1.10.0
    
    Synapse will now log a warning on start up if used with a PostgreSQL
    database that has a non-recommended locale set.
    
    
    See [Postgres](postgres.md) for details.
    
    
    # Upgrading to v1.8.0
    
    Specifying a `log_file` config option will now cause Synapse to refuse
    to start, and should be replaced by with the `log_config` option.
    Support for the `log_file` option was removed in v1.3.0 and has since
    had no effect.
    
    # Upgrading to v1.7.0
    
    In an attempt to configure Synapse in a privacy preserving way, the
    default behaviours of `allow_public_rooms_without_auth` and
    `allow_public_rooms_over_federation` have been inverted. This means that
    by default, only authenticated users querying the Client/Server API will
    be able to query the room directory, and relatedly that the server will
    not share room directory information with other servers over federation.
    
    If your installation does not explicitly set these settings one way or
    the other and you want either setting to be `true` then it will
    necessary to update your homeserver configuration file accordingly.
    
    For more details on the surrounding context see our
    [explainer](https://matrix.org/blog/2019/11/09/avoiding-unwelcome-visitors-on-private-matrix-servers).
    
    # Upgrading to v1.5.0
    
    This release includes a database migration which may take several
    minutes to complete if there are a large number (more than a million or
    so) of entries in the `devices` table. This is only likely to a be a
    problem on very large installations.
    
    # 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](usage/configuration/homeserver_sample_config.md)
    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:
    
    ```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:
    
    ```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`:
    
        ```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](metrics-howto.md#renaming-of-metrics--deprecation-of-old-names-in-12)
    
    for details.
    
    # Upgrading to v1.1.0
    
    Synapse v1.1.0 removes support for older Python and PostgreSQL versions,
    as outlined in [our deprecation
    notice](https://matrix.org/blog/2019/04/08/synapse-deprecating-postgres-9-4-and-python-2-x).
    
    ## Minimum Python Version
    
    Synapse v1.1.0 has a minimum Python requirement of Python 3.5. Python
    3.6 or Python 3.7 are recommended as they have improved internal string
    handling, significantly reducing memory usage.
    
    If you use current versions of the Matrix.org-distributed Debian
    packages or Docker images, action is not required.
    
    If you install Synapse in a Python virtual environment, please see
    "Upgrading to v0.34.0" for notes on setting up a new virtualenv under
    Python 3.
    
    ## Minimum PostgreSQL Version
    
    If using PostgreSQL under Synapse, you will need to use PostgreSQL 9.5
    or above. Please see the [PostgreSQL
    documentation](https://www.postgresql.org/docs/11/upgrading.html) for
    more details on upgrading your database.
    
    # Upgrading to v1.0
    
    ## Validation of TLS certificates
    
    Synapse v1.0 is the first release to enforce validation of TLS
    certificates for the federation API. It is therefore essential that your
    
    certificates are correctly configured.
    
    
    Note, v1.0 installations will also no longer be able to federate with
    servers that have not correctly configured their certificates.
    
    In rare cases, it may be desirable to disable certificate checking: for
    example, it might be essential to be able to federate with a given
    legacy server in a closed federation. This can be done in one of two
    ways:-
    
    -   Configure the global switch `federation_verify_certificates` to
        `false`.
    -   Configure a whitelist of server domains to trust via
        `federation_certificate_verification_whitelist`.
    
    
    See the [sample configuration file](usage/configuration/homeserver_sample_config.md)
    for more details on these settings.
    
    
    ## Email
    
    When a user requests a password reset, Synapse will send an email to the
    user to confirm the request.
    
    Previous versions of Synapse delegated the job of sending this email to
    an identity server. If the identity server was somehow malicious or
    became compromised, it would be theoretically possible to hijack an
    account through this means.
    
    Therefore, by default, Synapse v1.0 will send the confirmation email
    itself. If Synapse is not configured with an SMTP server, password reset
    via email will be disabled.
    
    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`.
    
    If you are absolutely certain that you wish to continue using an
    identity server for password resets, set
    `trust_identity_server_for_password_resets` to `true`.
    
    
    See the [sample configuration file](usage/configuration/homeserver_sample_config.md)
    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
    
    Please be aware that, before Synapse v1.0 is released around March 2019,
    you will need to replace any self-signed certificates with those
    
    verified by a root CA. Information on how to do so can be found at the
    ACME docs.
    
    
    # Upgrading to v0.34.0
    
    1.  This release is the first to fully support Python 3. Synapse will
        now run on Python versions 3.5, or 3.6 (as well as 2.7). We
        recommend switching to Python 3, as it has been shown to give
        performance improvements.
    
        For users who have installed Synapse into a virtualenv, we recommend
        doing this by creating a new virtualenv. For example:
    
    
        ```sh
        virtualenv -p python3 ~/synapse/env3
        source ~/synapse/env3/bin/activate
        pip install matrix-synapse
        ```
    
    
        You can then start synapse as normal, having activated the new
        virtualenv:
    
    
        ```sh
        cd ~/synapse
        source env3/bin/activate
        synctl start
        ```
    
    
        Users who have installed from distribution packages should see the
        relevant package documentation. See below for notes on Debian
        packages.
    
        -   When upgrading to Python 3, you **must** make sure that your log
            files are configured as UTF-8, by adding `encoding: utf8` to the
            `RotatingFileHandler` configuration (if you have one) in your
            `<server>.log.config` file. For example, if your `log.config`
            file contains:
    
    
            ```yaml
            handlers:
              file:
                class: logging.handlers.RotatingFileHandler
                formatter: precise
                filename: homeserver.log
                maxBytes: 104857600
                backupCount: 10
                filters: [context]
              console:
                class: logging.StreamHandler
                formatter: precise
                filters: [context]
            ```
    
    
            Then you should update this to be:
    
    
            ```yaml
            handlers:
              file:
                class: logging.handlers.RotatingFileHandler
                formatter: precise
                filename: homeserver.log
                maxBytes: 104857600
                backupCount: 10
                filters: [context]
                encoding: utf8
              console:
                class: logging.StreamHandler
                formatter: precise
                filters: [context]
            ```
    
    
            There is no need to revert this change if downgrading to
            Python 2.
    
        We are also making available Debian packages which will run Synapse
        on Python 3. You can switch to these packages with
        `apt-get install matrix-synapse-py3`, however, please read
        [debian/NEWS](https://github.com/matrix-org/synapse/blob/release-v0.34.0/debian/NEWS)
        before doing so. The existing `matrix-synapse` packages will
        continue to use Python 2 for the time being.
    
    2.  This release removes the `riot.im` from the default list of trusted
        identity servers.
    
        If `riot.im` is in your homeserver's list of
        `trusted_third_party_id_servers`, you should remove it. It was added
        in case a hypothetical future identity server was put there. If you
        don't remove it, users may be unable to deactivate their accounts.
    
    3.  This release no longer installs the (unmaintained) Matrix Console
        web client as part of the default installation. It is possible to
        re-enable it by installing it separately and setting the
        `web_client_location` config option, but please consider switching
        to another client.
    
    # Upgrading to v0.33.7
    
    This release removes the example email notification templates from
    `res/templates` (they are now internal to the python package). This
    should only affect you if you (a) deploy your Synapse instance from a
    git checkout or a github snapshot URL, and (b) have email notifications
    enabled.
    
    If you have email notifications enabled, you should ensure that
    `email.template_dir` is either configured to point at a directory where
    you have installed customised templates, or leave it unset to use the
    default templates.
    
    # Upgrading to v0.27.3
    
    This release expands the anonymous usage stats sent if the opt-in
    `report_stats` configuration is set to `true`. We now capture RSS memory
    and cpu use at a very coarse level. This requires administrators to
    install the optional `psutil` python module.
    
    We would appreciate it if you could assist by ensuring this module is
    available and `report_stats` is enabled. This will let us see if
    performance changes to synapse are having an impact to the general
    community.
    
    # Upgrading to v0.15.0
    
    If you want to use the new URL previewing API
    (`/_matrix/media/r0/preview_url`) then you have to explicitly enable it
    in the config and update your dependencies dependencies. See README.rst
    for details.
    
    # Upgrading to v0.11.0
    
    This release includes the option to send anonymous usage stats to
    matrix.org, and requires that administrators explictly opt in or out by
    setting the `report_stats` option to either `true` or `false`.
    
    We would really appreciate it if you could help our project out by
    reporting anonymized usage statistics from your homeserver. Only very
    basic aggregate data (e.g. number of users) will be reported, but it
    helps us to track the growth of the Matrix community, and helps us to
    make Matrix a success, as well as to convince other networks that they
    should peer with us.
    
    # Upgrading to v0.9.0
    
    Application services have had a breaking API change in this version.
    
    They can no longer register themselves with a home server using the AS
    HTTP API. This decision was made because a compromised application
    service with free reign to register any regex in effect grants full
    read/write access to the home server if a regex of `.*` is used. An
    attack where a compromised AS re-registers itself with `.*` was deemed
    too big of a security risk to ignore, and so the ability to register
    with the HS remotely has been removed.
    
    It has been replaced by specifying a list of application service
    registrations in `homeserver.yaml`:
    
    
    ```yaml
    app_service_config_files: ["registration-01.yaml", "registration-02.yaml"]
    ```
    
    
    Where `registration-01.yaml` looks like:
    
    
    ```yaml
    url: <String>  # e.g. "https://my.application.service.com"
    as_token: <String>
    hs_token: <String>
    sender_localpart: <String>  # This is a new field which denotes the user_id localpart when using the AS token
    namespaces:
      users:
        - exclusive: <Boolean>
          regex: <String>  # e.g. "@prefix_.*"
      aliases:
        - exclusive: <Boolean>
          regex: <String>
      rooms:
        - exclusive: <Boolean>
          regex: <String>
    ```
    
    
    # Upgrading to v0.8.0
    
    Servers which use captchas will need to add their public key to:
    
        static/client/register/register_config.js
    
          window.matrixRegistrationConfig = {
              recaptcha_public_key: "YOUR_PUBLIC_KEY"
          };
    
    This is required in order to support registration fallback (typically
    used on mobile devices).
    
    # Upgrading to v0.7.0
    
    New dependencies are:
    
    -   pydenticon
    -   simplejson
    -   syutil
    -   matrix-angular-sdk
    
    To pull in these dependencies in a virtual env, run:
    
        python synapse/python_dependencies.py | xargs -n 1 pip install
    
    # Upgrading to v0.6.0
    
    To pull in new dependencies, run:
    
        python setup.py develop --user
    
    This update includes a change to the database schema. To upgrade you
    first need to upgrade the database by running:
    
        python scripts/upgrade_db_to_v0.6.0.py <db> <server_name> <signing_key>
    
    
    Where `<db>` is the location of the database,
    `<server_name>` is the server name as specified in the
    synapse configuration, and `<signing_key>` is the location
    
    of the signing key as specified in the synapse configuration.
    
    This may take some time to complete. Failures of signatures and content
    hashes can safely be ignored.
    
    # Upgrading to v0.5.1
    
    Depending on precisely when you installed v0.5.0 you may have ended up
    with a stale release of the reference matrix webclient installed as a
    python module. To uninstall it and ensure you are depending on the
    latest module, please run:
    
        $ pip uninstall syweb
    
    # Upgrading to v0.5.0
    
    The webclient has been split out into a seperate repository/pacakage in
    this release. Before you restart your homeserver you will need to pull
    in the webclient package by running:
    
        python setup.py develop --user
    
    This release completely changes the database schema and so requires
    upgrading it before starting the new version of the homeserver.
    
    The script "database-prepare-for-0.5.0.sh" should be used to upgrade
    the database. This will save all user information, such as logins and
    profiles, but will otherwise purge the database. This includes messages,
    which rooms the home server was a member of and room alias mappings.
    
    If you would like to keep your history, please take a copy of your
    database file and ask for help in #matrix:matrix.org. The upgrade
    process is, unfortunately, non trivial and requires human intervention
    to resolve any resulting conflicts during the upgrade process.
    
    Before running the command the homeserver should be first completely
    shutdown. To run it, simply specify the location of the database, e.g.:
    
    > ./scripts/database-prepare-for-0.5.0.sh "homeserver.db"
    
    Once this has successfully completed it will be safe to restart the
    homeserver. You may notice that the homeserver takes a few seconds
    longer to restart than usual as it reinitializes the database.
    
    On startup of the new version, users can either rejoin remote rooms
    using room aliases or by being reinvited. Alternatively, if any other
    homeserver sends a message to a room that the homeserver was previously
    in the local HS will automatically rejoin the room.
    
    # Upgrading to v0.4.0
    
    This release needs an updated syutil version. Run:
    
        python setup.py develop
    
    You will also need to upgrade your configuration as the signing key
    format has changed. Run:
    
        python -m synapse.app.homeserver --config-path <CONFIG> --generate-config
    
    # Upgrading to v0.3.0
    
    This registration API now closely matches the login API. This introduces
    a bit more backwards and forwards between the HS and the client, but
    this improves the overall flexibility of the API. You can now GET on
    /register to retrieve a list of valid registration flows. Upon choosing
    one, they are submitted in the same way as login, e.g:
    
        {
          type: m.login.password,
          user: foo,
          password: bar
        }
    
    The default HS supports 2 flows, with and without Identity Server email
    authentication. Enabling captcha on the HS will add in an extra step to
    all flows: `m.login.recaptcha` which must be completed before you can
    transition to the next stage. There is a new login type:
    `m.login.email.identity` which contains the `threepidCreds` key which
    were previously sent in the original register request. For more
    information on this, see the specification.
    
    ## Web Client
    
    The VoIP specification has changed between v0.2.0 and v0.3.0. Users
    should refresh any browser tabs to get the latest web client code. Users
    on v0.2.0 of the web client will not be able to call those on v0.3.0 and
    vice versa.
    
    # Upgrading to v0.2.0
    
    The home server now requires setting up of SSL config before it can run.
    To automatically generate default config use:
    
        $ python synapse/app/homeserver.py \
            --server-name machine.my.domain.name \
            --bind-port 8448 \
            --config-path homeserver.config \
            --generate-config
    
    This config can be edited if desired, for example to specify a different
    SSL certificate to use. Once done you can run the home server using:
    
        $ python synapse/app/homeserver.py --config-path homeserver.config
    
    See the README.rst for more information.
    
    Also note that some config options have been renamed, including:
    
    -   "host" to "server-name"
    -   "database" to "database-path"
    -   "port" to "bind-port" and "unsecure-port"
    
    # Upgrading to v0.0.1
    
    This release completely changes the database schema and so requires
    upgrading it before starting the new version of the homeserver.
    
    The script "database-prepare-for-0.0.1.sh" should be used to upgrade
    the database. This will save all user information, such as logins and
    profiles, but will otherwise purge the database. This includes messages,
    which rooms the home server was a member of and room alias mappings.
    
    Before running the command the homeserver should be first completely
    shutdown. To run it, simply specify the location of the database, e.g.:
    
    > ./scripts/database-prepare-for-0.0.1.sh "homeserver.db"
    
    Once this has successfully completed it will be safe to restart the
    homeserver. You may notice that the homeserver takes a few seconds
    longer to restart than usual as it reinitializes the database.
    
    On startup of the new version, users can either rejoin remote rooms
    using room aliases or by being reinvited. Alternatively, if any other
    homeserver sends a message to a room that the homeserver was previously
    in the local HS will automatically rejoin the room.