Add (native) Traefik support to matrix-client-hydrogen

Previously, it had to go through matrix-nginx-proxy.
It's exposed to Traefik directly via container labels now

Serving at a path other than `/` doesn't work well yet.

group_vars/matrix_servers

@@ -2987,6 +2987,14 @@ matrix_client_hydrogen_container_image_self_build: "{{ matrix_architecture not i
 # the HTTP port to the local host.
 matrix_client_hydrogen_container_http_host_bind_port: "{{ (matrix_playbook_service_host_bind_interface_prefix ~ '8768') if matrix_playbook_service_host_bind_interface_prefix else '' }}"
 
+matrix_client_hydrogen_container_network: "{{ matrix_nginx_proxy_container_network if matrix_playbook_reverse_proxy_type == 'playbook-managed-nginx' else 'matrix-client-hydrogen' }}"
+
+matrix_client_hydrogen_container_additional_networks: "{{ [matrix_playbook_reverse_proxyable_services_additional_network] if matrix_playbook_reverse_proxyable_services_additional_network else [] }}"
+
+matrix_client_hydrogen_container_labels_traefik_enabled: "{{ matrix_playbook_reverse_proxy_type in ['playbook-managed-traefik', 'other-traefik-container'] }}"
+matrix_client_hydrogen_container_labels_traefik_docker_network: "{{ matrix_playbook_reverse_proxyable_services_additional_network }}"
+matrix_client_hydrogen_container_labels_traefik_entrypoints: "{{ devture_traefik_entrypoint_primary if devture_traefik_enabled else '' }}"
+
 matrix_client_hydrogen_default_hs_url: "{{ matrix_homeserver_url }}"
 
 matrix_client_hydrogen_self_check_validate_certificates: "{{ false if matrix_playbook_ssl_retrieval_method == 'self-signed' else true }}"

roles/custom/matrix-client-hydrogen/defaults/main.yml

@@ -14,17 +14,116 @@ matrix_client_hydrogen_docker_image_force_pull: "{{ matrix_client_hydrogen_docke
 matrix_client_hydrogen_data_path: "{{ matrix_base_data_path }}/client-hydrogen"
 matrix_client_hydrogen_docker_src_files_path: "{{ matrix_client_hydrogen_data_path }}/docker-src"
 
+# The base container network
+matrix_client_hydrogen_container_network: matrix-client-hydrogen
+
+# A list of additional container networks that the container would be connected to.
+# The role does not create these networks, so make sure they already exist.
+# Use this to expose this container to a reverse proxy, which runs in a different container network.
+matrix_client_hydrogen_container_additional_networks: []
+
 # Controls whether the container exposes its HTTP port (tcp/8080 in the container).
 #
 # Takes an "<ip>:<port>" or "<port>" value (e.g. "127.0.0.1:8768"), or empty string to not expose.
 matrix_client_hydrogen_container_http_host_bind_port: ''
 
+# matrix_client_hydrogen_container_labels_traefik_enabled controls whether labels to assist a Traefik reverse-proxy will be attached to the container.
+# See `../templates/labels.j2` for details.
+#
+# To inject your own other container labels, see `matrix_client_hydrogen_container_labels_additional_labels`.
+matrix_client_hydrogen_container_labels_traefik_enabled: true
+matrix_client_hydrogen_container_labels_traefik_docker_network: "{{ matrix_client_hydrogen_container_network }}"
+matrix_client_hydrogen_container_labels_traefik_hostname: "{{ matrix_server_fqn_element }}"
+# The path prefix must either be `/` or not end with a slash (e.g. `/hydrogen`).
+# For now, only `/` is supported due to problems with serving Hydrogen at a subpath.
+matrix_client_hydrogen_container_labels_traefik_path_prefix: /
+matrix_client_hydrogen_container_labels_traefik_rule: "Host(`{{ matrix_client_hydrogen_container_labels_traefik_hostname }}`){% if matrix_client_hydrogen_container_labels_traefik_path_prefix != '/' %} && PathPrefix(`{{ matrix_client_hydrogen_container_labels_traefik_path_prefix }}`){% endif %}"
+matrix_client_hydrogen_container_labels_traefik_priority: 0
+matrix_client_hydrogen_container_labels_traefik_entrypoints: web-secure
+matrix_client_hydrogen_container_labels_traefik_tls: "{{ matrix_client_hydrogen_container_labels_traefik_entrypoints != 'web' }}"
+matrix_client_hydrogen_container_labels_traefik_tls_certResolver: default  # noqa var-naming
+
+# Controls which additional headers to attach to all HTTP responses.
+# To add your own headers, use `matrix_client_hydrogen_container_labels_traefik_additional_response_headers_custom`
+matrix_client_hydrogen_container_labels_traefik_additional_response_headers: "{{ matrix_client_hydrogen_container_labels_traefik_additional_response_headers_auto | combine(matrix_client_hydrogen_container_labels_traefik_additional_response_headers_custom) }}"
+matrix_client_hydrogen_container_labels_traefik_additional_response_headers_auto: |
+  {{
+    {}
+    | combine ({'X-XSS-Protection': matrix_client_hydrogen_http_header_xss_protection} if matrix_client_hydrogen_http_header_xss_protection else {})
+    | combine ({'X-Frame-Options': matrix_client_hydrogen_http_header_frame_options} if matrix_client_hydrogen_http_header_frame_options else {})
+    | combine ({'X-Content-Type-Options': matrix_client_hydrogen_http_header_content_type_options} if matrix_client_hydrogen_http_header_content_type_options else {})
+    | combine ({'Content-Security-Policy': matrix_client_hydrogen_http_header_content_security_policy} if matrix_client_hydrogen_http_header_content_security_policy else {})
+    | combine ({'Permission-Policy': matrix_client_hydrogen_http_header_content_permission_policy} if matrix_client_hydrogen_http_header_content_permission_policy else {})
+    | combine ({'Strict-Transport-Security': matrix_client_hydrogen_http_header_strict_transport_security} if matrix_client_hydrogen_http_header_strict_transport_security and matrix_client_hydrogen_container_labels_traefik_tls else {})
+  }}
+matrix_client_hydrogen_container_labels_traefik_additional_response_headers_custom: {}
+
+# matrix_client_hydrogen_container_labels_additional_labels contains a multiline string with additional labels to add to the container label file.
+# See `../templates/labels.j2` for details.
+#
+# Example:
+# matrix_client_hydrogen_container_labels_additional_labels: |
+#   my.label=1
+#   another.label="here"
+matrix_client_hydrogen_container_labels_additional_labels: ''
+
 # A list of extra arguments to pass to the container
 matrix_client_hydrogen_container_extra_arguments: []
 
 # List of systemd services that matrix-client-hydrogen.service depends on
 matrix_client_hydrogen_systemd_required_services_list: ['docker.service']
 
+# Specifies the value of the `X-XSS-Protection` header
+# Stops pages from loading when they detect reflected cross-site scripting (XSS) attacks.
+#
+# Learn more about it is here:
+# - https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/X-XSS-Protection
+# - https://portswigger.net/web-security/cross-site-scripting/reflected
+matrix_client_hydrogen_http_header_xss_protection: "1; mode=block"
+
+# Specifies the value of the `X-Frame-Options` header which controls whether framing can happen.
+# See: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/X-Frame-Options
+matrix_client_hydrogen_http_header_frame_options: SAMEORIGIN
+
+# Specifies the value of the `X-Content-Type-Options` header.
+# See: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/X-Content-Type-Options
+matrix_client_hydrogen_http_header_content_type_options: nosniff
+
+# Specifies the value of the `Content-Security-Policy` header.
+# See: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy
+matrix_client_hydrogen_http_header_content_security_policy: frame-ancestors 'self'
+
+# Specifies the value of the `Permission-Policy` header.
+# See: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Permission-Policy
+matrix_client_hydrogen_http_header_content_permission_policy: "{{ 'interest-cohort=() always' if matrix_client_hydrogen_floc_optout_enabled else '' }}"
+
+# Specifies the value of the `Strict-Transport-Security` header.
+# See: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Strict-Transport-Security
+matrix_client_hydrogen_http_header_strict_transport_security: "{{ '\"max-age=31536000; includeSubDomains; preload\" always' if matrix_client_hydrogen_hsts_preload_enabled else '\"max-age=31536000; includeSubDomains\" always' }}"
+
+# Controls whether to send a "Permissions-Policy interest-cohort=();" header along with all responses
+#
+# Learn more about what it is here:
+# - https://www.eff.org/deeplinks/2021/03/googles-floc-terrible-idea
+# - https://paramdeo.com/blog/opting-your-website-out-of-googles-floc-network
+# - https://amifloced.org/
+#
+# Of course, a better solution is to just stop using browsers (like Chrome), which participate in such tracking practices.
+# See: `matrix_client_hydrogen_content_permission_policy`
+matrix_client_hydrogen_floc_optout_enabled: true
+
+# Controls if HSTS preloading is enabled
+#
+# In its strongest and recommended form, the [HSTS policy](https://www.chromium.org/hsts) includes all subdomains, and
+# indicates a willingness to be "preloaded" into browsers:
+# `Strict-Transport-Security: max-age=31536000; includeSubDomains; preload`
+# For more information visit:
+# - https://en.wikipedia.org/wiki/HTTP_Strict_Transport_Security
+# - https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Strict-Transport-Security
+# - https://hstspreload.org/#opt-in
+# See: `matrix_client_hydrogen_http_header_strict_transport_security`
+matrix_client_hydrogen_hsts_preload_enabled: false
+
 # Controls whether the self-check feature should validate SSL certificates.
 matrix_client_hydrogen_self_check_validate_certificates: true
 

roles/custom/matrix-client-hydrogen/tasks/setup_install.yml

@@ -52,7 +52,7 @@
     group: "{{ matrix_user_groupname }}"
   with_items:
     - {src: "{{ role_path }}/templates/nginx.conf.j2", name: "nginx.conf"}
-  when: "item.src is not none"
+    - {src: "{{ role_path }}/templates/labels.j2", name: "labels"}
 
 - name: Ensure Hydrogen Docker image is built
   community.docker.docker_image:
@@ -65,6 +65,11 @@
       pull: true
   when: "matrix_client_hydrogen_container_image_self_build | bool"
 
+- name: Ensure Hydrogen container network is created
+  community.general.docker_network:
+    name: "{{ matrix_client_hydrogen_container_network }}"
+    driver: bridge
+
 - name: Ensure matrix-client-hydrogen.service installed
   ansible.builtin.template:
     src: "{{ role_path }}/templates/systemd/matrix-client-hydrogen.service.j2"

roles/custom/matrix-client-hydrogen/tasks/validate_config.yml

@@ -7,3 +7,34 @@
   when: "(vars[item] == '' or vars[item] is none) and matrix_client_hydrogen_container_image_self_build | bool"
   with_items:
     - "matrix_client_hydrogen_default_hs_url"
+
+- when: matrix_client_hydrogen_container_labels_traefik_enabled | bool
+  block:
+    - name: Fail if required matrix-client-hydrogen Traefik settings not defined
+      ansible.builtin.fail:
+        msg: >-
+          You need to define a required configuration setting (`{{ item }}`).
+      when: "vars[item] == ''"
+      with_items:
+        - matrix_client_hydrogen_container_labels_traefik_hostname
+        - matrix_client_hydrogen_container_labels_traefik_path_prefix
+
+    # We ensure it doesn't end with a slash, because we handle both (slash and no-slash).
+    # Knowing that `matrix_client_hydrogen_container_labels_traefik_path_prefix` does not end with a slash
+    # ensures we know how to set these routes up without having to do "does it end with a slash" checks elsewhere.
+    - name: Fail if matrix_client_hydrogen_container_labels_traefik_path_prefix ends with a slash
+      ansible.builtin.fail:
+        msg: >-
+          matrix_client_hydrogen_container_labels_traefik_path_prefix (`{{ matrix_client_hydrogen_container_labels_traefik_path_prefix }}`) must either be `/` or not end with a slash (e.g. `/hydrogen`).
+      when: "matrix_client_hydrogen_container_labels_traefik_path_prefix != '/' and matrix_client_hydrogen_container_labels_traefik_path_prefix[-1] == '/'"
+
+    # For example, we're getting errors like this:
+    # > main.js:51 Failed to load stylesheet from https://DOMAIN/assets/theme-element-light.5316e268.css:
+    # despite having set a prefix of `/hydrogen`.
+    # This is yet to be investigated and workaround around.
+    - name: Fail if matrix_client_hydrogen_container_labels_traefik_path_prefix is not /
+      ansible.builtin.fail:
+        msg: >-
+          matrix_client_hydrogen_container_labels_traefik_path_prefix can only be set to `/` right now.
+          Serving Hydrogen from another path doesn't work just yet.
+      when: "matrix_client_hydrogen_container_labels_traefik_path_prefix != '/'"

roles/custom/matrix-client-hydrogen/templates/labels.j2

@@ -0,0 +1,45 @@
+{% if matrix_client_hydrogen_container_labels_traefik_enabled %}
+traefik.enable=true
+
+{% if matrix_client_hydrogen_container_labels_traefik_docker_network %}
+traefik.docker.network={{ matrix_client_hydrogen_container_labels_traefik_docker_network }}
+{% endif %}
+
+{% set middlewares = [] %}
+
+{% if matrix_client_hydrogen_container_labels_traefik_path_prefix != '/' %}
+traefik.http.middlewares.matrix-client-hydrogen-slashless-redirect.redirectregex.regex=({{ matrix_client_hydrogen_container_labels_traefik_path_prefix | quote }})$
+traefik.http.middlewares.matrix-client-hydrogen-slashless-redirect.redirectregex.replacement=${1}/
+{% set middlewares = middlewares + ['matrix-client-hydrogen-slashless-redirect'] %}
+{% endif %}
+
+{% if matrix_client_hydrogen_container_labels_traefik_path_prefix != '/' %}
+traefik.http.middlewares.matrix-client-hydrogen-strip-prefix.stripprefix.prefixes={{ matrix_client_hydrogen_container_labels_traefik_path_prefix }}
+{% set middlewares = middlewares + ['matrix-client-hydrogen-strip-prefix'] %}
+{% endif %}
+
+{% if matrix_client_hydrogen_container_labels_traefik_additional_response_headers.keys() | length > 0 %}
+{% for name, value in matrix_client_hydrogen_container_labels_traefik_additional_response_headers.items() %}
+traefik.http.middlewares.matrix-client-hydrogen-add-headers.headers.customresponseheaders.{{ name }}={{ value }}
+{% endfor %}
+{% set middlewares = middlewares + ['matrix-client-hydrogen-add-headers'] %}
+{% endif %}
+
+traefik.http.routers.matrix-client-hydrogen.rule={{ matrix_client_hydrogen_container_labels_traefik_rule }}
+{% if matrix_client_hydrogen_container_labels_traefik_priority | int > 0 %}
+traefik.http.routers.matrix-client-hydrogen.priority={{ matrix_client_hydrogen_container_labels_traefik_priority }}
+{% endif %}
+traefik.http.routers.matrix-client-hydrogen.service=matrix-client-hydrogen
+{% if middlewares | length > 0 %}
+traefik.http.routers.matrix-client-hydrogen.middlewares={{ middlewares | join(',') }}
+{% endif %}
+traefik.http.routers.matrix-client-hydrogen.entrypoints={{ matrix_client_hydrogen_container_labels_traefik_entrypoints }}
+traefik.http.routers.matrix-client-hydrogen.tls={{ matrix_client_hydrogen_container_labels_traefik_tls | to_json }}
+{% if matrix_client_hydrogen_container_labels_traefik_tls %}
+traefik.http.routers.matrix-client-hydrogen.tls.certResolver={{ matrix_client_hydrogen_container_labels_traefik_tls_certResolver }}
+{% endif %}
+
+traefik.http.services.matrix-client-hydrogen.loadbalancer.server.port=8080
+{% endif %}
+
+{{ matrix_client_hydrogen_container_labels_additional_labels }}

roles/custom/matrix-client-hydrogen/templates/systemd/matrix-client-hydrogen.service.j2

@@ -13,15 +13,18 @@ Environment="HOME={{ devture_systemd_docker_base_systemd_unit_home_path }}"
 ExecStartPre=-{{ devture_systemd_docker_base_host_command_sh }} -c '{{ devture_systemd_docker_base_host_command_docker }} kill matrix-client-hydrogen 2>/dev/null || true'
 ExecStartPre=-{{ devture_systemd_docker_base_host_command_sh }} -c '{{ devture_systemd_docker_base_host_command_docker }} rm matrix-client-hydrogen 2>/dev/null || true'
 
-ExecStart={{ devture_systemd_docker_base_host_command_docker }} run --rm --name matrix-client-hydrogen \
+ExecStartPre={{ devture_systemd_docker_base_host_command_docker }} create \
+			--rm \
+			--name=matrix-client-hydrogen \
 			--log-driver=none \
 			--user={{ matrix_user_uid }}:{{ matrix_user_gid }} \
 			--cap-drop=ALL \
 			--read-only \
-			--network={{ matrix_docker_network }} \
+			--network={{ matrix_client_hydrogen_container_network }} \
 			{% if matrix_client_hydrogen_container_http_host_bind_port %}
 			-p {{ matrix_client_hydrogen_container_http_host_bind_port }}:8080 \
 			{% endif %}
+			--label-file={{ matrix_client_hydrogen_data_path }}/labels \
 			--tmpfs=/tmp:rw,noexec,nosuid,size=10m \
 			--mount type=bind,src={{ matrix_client_hydrogen_data_path }}/nginx.conf,dst=/etc/nginx/nginx.conf,ro \
 			--mount type=bind,src={{ matrix_client_hydrogen_data_path }}/config.json,dst=/config.json.bundled,ro \
@@ -30,8 +33,15 @@ ExecStart={{ devture_systemd_docker_base_host_command_docker }} run --rm --name
 			{% endfor %}
 			{{ matrix_client_hydrogen_docker_image }}
 
+{% for network in matrix_client_hydrogen_container_additional_networks %}
+ExecStartPre={{ devture_systemd_docker_base_host_command_docker }} network connect {{ network }} matrix-client-hydrogen
+{% endfor %}
+
+ExecStart={{ devture_systemd_docker_base_host_command_docker }} start --attach matrix-client-hydrogen
+
 ExecStop=-{{ devture_systemd_docker_base_host_command_sh }} -c '{{ devture_systemd_docker_base_host_command_docker }} kill matrix-client-hydrogen 2>/dev/null || true'
 ExecStop=-{{ devture_systemd_docker_base_host_command_sh }} -c '{{ devture_systemd_docker_base_host_command_docker }} rm matrix-client-hydrogen 2>/dev/null || true'
+
 Restart=always
 RestartSec=30
 SyslogIdentifier=matrix-client-hydrogen