Add synapse-admin support

Fixes #562 (Github Issue)

roles/matrix-synapse-admin/tasks/init.yml

@@ -0,0 +1,50 @@
+- set_fact:
+    matrix_systemd_services_list: "{{ matrix_systemd_services_list + ['matrix-synapse-admin'] }}"
+  when: matrix_synapse_admin_enabled|bool
+
+- block:
+  - name: Fail if matrix-nginx-proxy role already executed
+    fail:
+      msg: >-
+        Trying to append Synapse Admin's reverse-proxying configuration to matrix-nginx-proxy,
+        but it's pointless since the matrix-nginx-proxy role had already executed.
+        To fix this, please change the order of roles in your plabook,
+        so that the matrix-nginx-proxy role would run after the matrix-synapse-admin role.
+    when: matrix_nginx_proxy_role_executed|default(False)|bool
+
+  - name: Generate Synapse Admin proxying configuration for matrix-nginx-proxy
+    set_fact:
+      matrix_synapse_admin_matrix_nginx_proxy_configuration: |
+        location ~ ^{{ matrix_synapse_admin_public_endpoint }}/?(.*) {
+        {% if matrix_nginx_proxy_enabled|default(False) %}
+          {# Use the embedded DNS resolver in Docker containers to discover the service #}
+          resolver 127.0.0.11 valid=5s;
+          set $backend "matrix-synapse-admin:80";
+          proxy_pass http://$backend/$1;
+        {% else %}
+          {# Generic configuration for use outside of our container setup #}
+          proxy_pass http://127.0.0.1:8766/$1;
+        {% endif %}
+        }
+
+  - name: Register Synapse Admin proxying configuration with matrix-nginx-proxy
+    set_fact:
+      matrix_nginx_proxy_proxy_matrix_additional_server_configuration_blocks: |
+        {{
+          matrix_nginx_proxy_proxy_matrix_additional_server_configuration_blocks|default([])
+          +
+          [matrix_synapse_admin_matrix_nginx_proxy_configuration]
+        }}
+  tags:
+    - always
+  when: matrix_synapse_admin_enabled|bool
+
+- name: Warn about reverse-proxying if matrix-nginx-proxy not used
+  debug:
+    msg: >-
+      NOTE: You've enabled the Synapse Admin tool but are not using the matrix-nginx-proxy
+      reverse proxy.
+      Please make sure that you're proxying the `{{ matrix_synapse_admin_public_endpoint }}`
+      URL endpoint to the matrix-synapse-admin container.
+      You can expose the container's port using the `matrix_synapse_admin_container_http_host_bind_port` variable.
+  when: "matrix_synapse_admin_enabled|bool and matrix_nginx_proxy_enabled is not defined"

roles/matrix-synapse-admin/tasks/main.yml

@@ -0,0 +1,8 @@
+- import_tasks: "{{ role_path }}/tasks/init.yml"
+  tags:
+    - always
+
+- import_tasks: "{{ role_path }}/tasks/setup.yml"
+  tags:
+    - setup-all
+    - setup-synapse-admin

roles/matrix-synapse-admin/tasks/setup.yml

@@ -0,0 +1,60 @@
+---
+
+#
+# Tasks related to setting up matrix-synapse-admin
+#
+
+- name: Ensure matrix-synapse-admin image is pulled
+  docker_image:
+    name: "{{ matrix_synapse_admin_docker_image }}"
+    source: "{{ 'pull' if ansible_version.major > 2 or ansible_version.minor > 7 else omit }}"
+    force_source: "{{ matrix_synapse_admin_docker_image_force_pull if ansible_version.major > 2 or ansible_version.minor >= 8 else omit }}"
+    force: "{{ omit if ansible_version.major > 2 or ansible_version.minor >= 8 else matrix_synapse_admin_docker_image_force_pull }}"
+  when: matrix_synapse_admin_enabled|bool
+
+- name: Ensure matrix-matrix-synapse-admin.service installed
+  template:
+    src: "{{ role_path }}/templates/systemd/matrix-synapse-admin.service.j2"
+    dest: "{{ matrix_systemd_path }}/matrix-synapse-admin.service"
+    mode: 0644
+  register: matrix_synapse_admin_systemd_service_result
+  when: matrix_synapse_admin_enabled|bool
+
+- name: Ensure systemd reloaded after matrix-matrix-synapse-admin.service installation
+  service:
+    daemon_reload: yes
+  when: "matrix_synapse_admin_enabled|bool and matrix_synapse_admin_systemd_service_result.changed"
+
+#
+# Tasks related to getting rid of matrix-synapse-admin (if it was previously enabled)
+#
+
+- name: Check existence of matrix-matrix-synapse-admin service
+  stat:
+    path: "{{ matrix_systemd_path }}/matrix-matrix-synapse-admin.service"
+  register: matrix_synapse_admin_service_stat
+
+- name: Ensure matrix-matrix-synapse-admin is stopped
+  service:
+    name: matrix-matrix-synapse-admin
+    state: stopped
+    daemon_reload: yes
+  register: stopping_result
+  when: "not matrix_synapse_admin_enabled|bool and matrix_synapse_admin_service_stat.stat.exists"
+
+- name: Ensure matrix-matrix-synapse-admin.service doesn't exist
+  file:
+    path: "{{ matrix_systemd_path }}/matrix-matrix-synapse-admin.service"
+    state: absent
+  when: "not matrix_synapse_admin_enabled|bool and matrix_synapse_admin_service_stat.stat.exists"
+
+- name: Ensure systemd reloaded after matrix-matrix-synapse-admin.service removal
+  service:
+    daemon_reload: yes
+  when: "not matrix_synapse_admin_enabled|bool and matrix_synapse_admin_service_stat.stat.exists"
+
+- name: Ensure matrix-synapse-admin Docker image doesn't exist
+  docker_image:
+    name: "{{ matrix_synapse_admin_docker_image }}"
+    state: absent
+  when: "not matrix_synapse_admin_enabled|bool"