Automagic restart handlers

README.md

@@ -95,6 +95,16 @@ Options below that control individual file or subdirectory placement can still o
 [custom]: vars/layout-custom.yml
 [fhs]: http://www.pathname.com/fhs/
 
+**New options for Galaxy 22.01 and later**
+
+The role can now manage the Galaxy service using [gravity][gravity]. This is the default for Galaxy 22.05 and later.
+Additionally, support for the `galaxy_restart_handler_name` variable has been removed. If you need to enable your own
+custom restart handler, you can use the "`listen`" option to the handler as explained in the
+[handler documentation](https://docs.ansible.com/ansible/latest/user_guide/playbooks_handlers.html#using-variables-with-handlers).
+The handler should "listen" to the topic `"restart galaxy"`.
+
+[gravity]: https://github.com/galaxyproject/gravity
+
 **New options for Galaxy 18.01 and later**
 
 - `galaxy_config_style` (default: `yaml`): The type of Galaxy configuration file to write, `yaml` for the YAML format supported by uWSGI or `ini-paste` for the traditional PasteDeploy-style INI file
@@ -223,10 +233,13 @@ Several variables control which functions this role will perform (all default to
 - `galaxy_build_client`: Build the Galaxy client application (web UI).
 - `galaxy_client_make_target` (default: `client-production-maps`): Set the client build type. Options include: `client`,
   `client-production` and `client-production-maps`. See [Galaxy client readme][client-build] for details.
+- `galaxy_manage_systemd` (default: `no`): Install a [systemd][systemd] service unit to start and stop Galaxy with the
+  system (and using the `systemctl` command).
 - `galaxy_manage_errordocs` (default: `no`): Install Galaxy-styled 413 and 502 HTTP error documents for nginx. Requires
   write privileges for the nginx error document directory.
 
 [client-build]: https://github.com/galaxyproject/galaxy/blob/dev/client/README.md#complete-client-build
+[systemd]: https://www.freedesktop.org/wiki/Software/systemd/
 
 **Galaxy code and configuration**
 
@@ -323,6 +336,23 @@ The role needs to perform tasks as different users depending on which features y
 connecting to the target host. By default, the role will use `become` (i.e. sudo) to perform tasks as the appropriate
 user if deemed necessary. Overriding this behavior is discussed in the [defaults file][defaults].
 
+**systemd**
+
+[systemd][systemd] is the standard system init daemon on most modern Linux flavors (and all of the ones supported by
+this role). If `galaxy_manage_systemd` is enabled, a `galaxy` service will be configured in systemd to run Galaxy. This
+service will be automatically started and configured to start when your system boots. You can control the Galaxy
+service with the `systemctl` utility as the `root` user or with `sudo`:
+
+```console
+# systemctl start galaxy     # start galaxy
+# systemctl reload galaxy    # attempt a "graceful" reload
+# systemctl restart galaxy   # perform a hard restart
+# systemctl stop galaxy      # stop galaxy
+```
+
+You can use systemd user mode if you do not have root privileges on your system by setting `galaxy_systemd_root` to
+`false`. Add `--user` to the `systemctl` commands above to interact with systemd in user mode:
+
 **Error documents**
 
 - `galaxy_errordocs_dir`: Install Galaxy-styled HTTP 413 and 502 error documents under this directory. The 502 message
@@ -334,9 +364,6 @@ user if deemed necessary. Overriding this behavior is discussed in the [defaults
 
 **Miscellaneous options**
 
-- `galaxy_restart_handler_name`: The role doesn't restart Galaxy since it doesn't control how Galaxy is started and
-  stopped. Because of this, you can write your own restart handler and inform the role of your handler's name with this
-  variable. See the examples
 - `galaxy_admin_email_to`: If set, email this address when Galaxy has been updated. Assumes mail is properly configured
   on the managed host.
 - `galaxy_admin_email_from`: Address to send the aforementioned email from.
@@ -398,7 +425,6 @@ Install Galaxy as per the current production server best practices:
     galaxy_user: galaxy
     galaxy_privsep_user: gxpriv
     galaxy_group: galaxy
-    galaxy_restart_handler_name: Restart Galaxy
     postgresql_objects_users:
       - name: galaxy
         password: null
@@ -453,6 +479,7 @@ Install Galaxy as per the current production server best practices:
       supervisorctl:
         name: galaxy
         state: restarted
+      listen: restart galaxy
 ```
 
 License

defaults/main.yml

@@ -302,19 +302,17 @@ galaxy_client_build_steps:
     - stageLibs
     - plugins
 
-# Restart handler is already set if using the systemd options in this role, otherwise you need to define one yourself
-galaxy_restart_handler_name: "{{ 'galaxy ' ~ galaxy_systemd_mode ~ ' restart' if galaxy_manage_systemd else 'default restart galaxy handler' }}"
-
 #
 # systemd options
 #
 
 # Currently `mule` (aka uWSGI) and `gravity` (runs Galaxy 22.01+ under gunicorn) are supported
-galaxy_systemd_mode: mule
+galaxy_systemd_mode: "{{ 'mule' if __galaxy_major_version is version('22.05', '<') else 'gravity' }}"
 
 # Control whether the systemd service unit is installed/controlled as root or the Galaxy user
 galaxy_systemd_root: true
 
+# The command that systemd will run to start Galaxy, depends on galaxy_systemd_mode or override
 galaxy_systemd_command: "{{ __galaxy_systemd_command[galaxy_systemd_mode] }}"
 __galaxy_systemd_command:
   mule: "{{ galaxy_venv_dir }}/bin/uwsgi {{ '--yaml' if galaxy_config_style in ('yaml', 'yml') else '--ini' }} {{ galaxy_config_file }}"

handlers/main.yml

@@ -1,37 +1,33 @@
 ---
 # defaults file for galaxyproject.galaxy
 
-- name: default restart galaxy handler
-  debug:
-    msg: "RESTARTER NOT IMPLEMENTED - Please restart Galaxy manually. You can define your own handler and enable it with `galaxy_restart_handler_name`"
-
-- name: daemon reload
+- name: systemd daemon reload
   systemd:
     daemon_reload: yes
     scope: "{{ galaxy_systemd_root | ternary(omit, 'user') }}"
 
-- name: galaxy mule start
+- name: galaxy systemd start
   systemd:
     name: galaxy.service
     state: started
     scope: "{{ galaxy_systemd_root | ternary(omit, 'user') }}"
+  when: "galaxy_systemd_mode == 'gravity'"
+  listen: "start galaxy"
 
 - name: galaxy mule restart
   systemd:
     name: galaxy.service
     state: restarted
     scope: "{{ galaxy_systemd_root | ternary(omit, 'user') }}"
-
-- name: galaxy gravity start
-  systemd:
-    name: galaxy.service
-    state: started
-    scope: "{{ galaxy_systemd_root | ternary(omit, 'user') }}"
+  when: "galaxy_systemd_mode == 'mule'"
+  listen: "restart galaxy"
 
 - name: galaxy gravity restart
   command: "{{ galaxy_venv_dir }}/bin/galaxyctl graceful"
   environment:
     GRAVITY_STATE_DIR: "{{ galaxy_gravity_state_dir }}"
+  when: "galaxy_systemd_mode == 'gravity'"
+  listen: "restart galaxy"
 
 - name: galaxyctl update
   command: "{{ galaxy_venv_dir }}/bin/galaxyctl update"

tasks/clone.yml

@@ -15,7 +15,7 @@
       diff: "{{ galaxy_diff_mode_verbose }}"
       register: __galaxy_git_update_result
       notify:
-        - "{{ galaxy_restart_handler_name }}"
+        - restart galaxy
 
     - name: Report Galaxy version change
       debug:

tasks/main.yml

@@ -134,9 +134,9 @@
   tags:
     - galaxy_manage_gravity
 
-- name: Include systemd unit setup tasks (Mules)
+- name: Include systemd unit setup tasks (Galaxy)
   include_tasks:
-    file: systemd-mule.yml
+    file: systemd-galaxy.yml
     apply:
       tags: galaxy_manage_systemd
   when: galaxy_manage_systemd and galaxy_systemd_mode in ["mule", "gravity"]

tasks/static_setup.yml

@@ -16,7 +16,7 @@
         mode: "{{ galaxy_config_perms }}"
       with_items: "{{ galaxy_config_files }}"
       notify:
-        - "{{ galaxy_restart_handler_name }}"
+        - restart galaxy
 
     - name: Install additional Galaxy config files (template)
       template:
@@ -26,7 +26,7 @@
         mode: "{{ galaxy_config_perms }}"
       with_items: "{{ galaxy_config_templates }}"
       notify:
-        - "{{ galaxy_restart_handler_name }}"
+        - restart galaxy
 
     - name: Install local tools
       copy:
@@ -128,7 +128,7 @@
         mode: "{{ galaxy_config_perms }}"
       notify:
         - galaxyctl update
-        - "{{ galaxy_restart_handler_name }}"
+        - restart galaxy
 
   remote_user: "{{ galaxy_remote_users.privsep | default(__galaxy_remote_user) }}"
   become: "{{ true if galaxy_become_users.privsep is defined else __galaxy_become }}"

tasks/systemd-mule.yml → tasks/systemd-galaxy.yml

@@ -3,6 +3,10 @@
 - name: Manage Paths
   block:
 
+    - name: Ensure Galaxy version is set
+      include_tasks: _inc_galaxy_version.yml
+      when: __galaxy_major_version is undefined
+
     - name: Deploy Galaxy Unit
       template:
         owner: "{{ galaxy_systemd_root | ternary('root', omit) }}"
@@ -11,10 +15,11 @@
         src: systemd/galaxy.service.j2
         dest: "{{ galaxy_systemd_root | ternary('/etc/systemd/system/', ('~' ~ __galaxy_user_name ~ '/.config/systemd/user') | expanduser) }}/galaxy.service"
       notify:
-        - daemon reload
-        - "{{ galaxy_restart_handler_name }}"
+        - systemd daemon reload
+        - start galaxy
+        - restart galaxy
 
-    - name: Enable Galaxy Unit
+    - name: Enable Galaxy service unit
       systemd:
         name: galaxy.service
         enabled: yes