matrix-docker-ansible-deploy/docs/configuring-playbook-synapse.md

Configuring Synapse (optional)

By default, this playbook configures the Synapse Matrix server, so that it works for the general case. If that’s enough for you, you can skip this document.

The playbook provides lots of customization variables you could use to change Synapse’s settings.

Their defaults are defined in roles/matrix-synapse/defaults/main.yml and they ultimately end up in the generated /matrix/synapse/config/homeserver.yaml file (on the server). This file is generated from the roles/matrix-synapse/templates/synapse/homeserver.yaml.j2 template.

If there’s an existing variable which controls a setting you wish to change, you can simply define that variable in your configuration file (inventory/host_vars/matrix.<your-domain>/vars.yml) and re-run the playbook to apply the changes.

Alternatively, if there is no pre-defined variable for a Synapse setting you wish to change:

• you can either request a variable to be created (or you can submit such a contribution yourself). Keep in mind that it’s probably not a good idea to create variables for each one of Synapse’s various settings that rarely get used.

• or, you can extend and override the default configuration (homeserver.yaml.j2) by making use of the matrix_synapse_configuration_extension_yaml variable. You can find information about this in roles/matrix-synapse/defaults/main.yml.

• or, if extending the configuration is still not powerful enough for your needs, you can override the configuration completely using matrix_synapse_configuration (or matrix_synapse_configuration_yaml). You can find information about this in roles/matrix-synapse/defaults/main.yml.

Synapse OpenID Connect

If you plan to rely only on SSO and don’t want your users to ever login with password credentials disable this:

matrix_synapse_password_config_enabled: true

Add this to allow seamless forwarding to element web app and element android app. Without this setting matrix will ask the user if he trusts the app he tries to login.

matrix_synapse_sso_client_whitelist:
  - "https://element.{{ matrix_domain }}/"
  - element://element

If you use nginx proxy role then you should add this setting as well to successfully pass redirects:

matrix_nginx_proxy_proxy_matrix_client_api_forwarded_location_synapse_oidc_api_enabled: true

Refer to official Synapse doc for oidc setup examples.

This is the bare minimum config example:

# Configure open id connect
matrix_synapse_oidc_enabled: true
matrix_synapse_oidc_issuer: "https://openid.example.com"
matrix_synapse_oidc_client_id: "your-client-id"
matrix_synapse_oidc_client_secret: "s0m3v3RyS3cr3tStr!ng"

Depending on oauth provider you may also like to change following settings:

matrix_synapse_oidc_scopes: ["openid"]
matrix_synapse_oidc_allow_existing_users: false
matrix_synapse_oidc_client_auth_method: client_secret_basic
matrix_synapse_oidc_subject_claim: "sub"
matrix_synapse_oidc_localpart_template: "{% raw %}{{ user.preferred_username }}{% endraw %}"
matrix_synapse_oidc_display_name_template: "{% raw %}{{ user.name }}{% endraw %}"

Synapse Admin

Certain Synapse administration tasks (managing users and rooms, etc.) can be performed via a web user-interace, if you install Synapse Admin.

Synapse + OpenID Connect for Single-Sign-On

If you’d like to use OpenID Connect authentication with Synapse, you’ll need some additional reverse-proxy configuration (see our nginx reverse-proxy doc page).