Refactor the Dockerfile-workers configuration script to use Jinja2 templates in Synapse workers' Supervisord blocks. (#13054)

Co-authored-by: Richard van der Hoff <1389908+richvdh@users.noreply.github.com>

changelog.d/13054.misc

@@ -0,0 +1 @@
+Refactor the Dockerfile-workers configuration script to use Jinja2 templates in Synapse workers' Supervisord blocks.

docker/conf-workers/supervisord.conf.j2

@@ -31,17 +31,3 @@ autorestart=true
 # Redis can be disabled if the image is being used without workers
 autostart={{ enable_redis }}
 
-[program:synapse_main]
-command=/usr/local/bin/prefix-log /usr/local/bin/python -m synapse.app.homeserver --config-path="{{ main_config_path }}" --config-path=/conf/workers/shared.yaml
-priority=10
-# Log startup failures to supervisord's stdout/err
-# Regular synapse logs will still go in the configured data directory
-stdout_logfile=/dev/stdout
-stdout_logfile_maxbytes=0
-stderr_logfile=/dev/stderr
-stderr_logfile_maxbytes=0
-autorestart=unexpected
-exitcodes=0
-
-# Additional process blocks
-{{ worker_config }}

docker/conf-workers/synapse.supervisord.conf.j2

@@ -0,0 +1,30 @@
+[program:synapse_main]
+command=/usr/local/bin/prefix-log /usr/local/bin/python -m synapse.app.homeserver
+  --config-path="{{ main_config_path }}"
+  --config-path=/conf/workers/shared.yaml
+priority=10
+# Log startup failures to supervisord's stdout/err
+# Regular synapse logs will still go in the configured data directory
+stdout_logfile=/dev/stdout
+stdout_logfile_maxbytes=0
+stderr_logfile=/dev/stderr
+stderr_logfile_maxbytes=0
+autorestart=unexpected
+exitcodes=0
+
+
+{% for worker in workers %}
+[program:synapse_{{ worker.name }}]
+command=/usr/local/bin/prefix-log /usr/local/bin/python -m {{ worker.app }}
+  --config-path="{{ main_config_path }}"
+  --config-path=/conf/workers/shared.yaml
+  --config-path=/conf/workers/{{ worker.name }}.yaml
+autorestart=unexpected
+priority=500
+exitcodes=0
+stdout_logfile=/dev/stdout
+stdout_logfile_maxbytes=0
+stderr_logfile=/dev/stderr
+stderr_logfile_maxbytes=0
+
+{% endfor %}

docker/configure_workers_and_start.py

@@ -176,21 +176,6 @@ WORKERS_CONFIG: Dict[str, Dict[str, Any]] = {
 }
 
 # Templates for sections that may be inserted multiple times in config files
-SUPERVISORD_PROCESS_CONFIG_BLOCK = """
-[program:synapse_{name}]
-command=/usr/local/bin/prefix-log /usr/local/bin/python -m {app} \
-    --config-path="{config_path}" \
-    --config-path=/conf/workers/shared.yaml \
-    --config-path=/conf/workers/{name}.yaml
-autorestart=unexpected
-priority=500
-exitcodes=0
-stdout_logfile=/dev/stdout
-stdout_logfile_maxbytes=0
-stderr_logfile=/dev/stderr
-stderr_logfile_maxbytes=0
-"""
-
 NGINX_LOCATION_CONFIG_BLOCK = """
     location ~* {endpoint} {{
         proxy_pass {upstream};
@@ -353,13 +338,10 @@ def generate_worker_files(
     # This config file will be passed to all workers, included Synapse's main process.
     shared_config: Dict[str, Any] = {"listeners": listeners}
 
-    # The supervisord config. The contents of which will be inserted into the
+    # List of dicts that describe workers.
-    # base supervisord jinja2 template.
+    # We pass this to the Supervisor template later to generate the appropriate
-    #
+    # program blocks.
-    # Supervisord will be in charge of running everything, from redis to nginx to Synapse
+    worker_descriptors: List[Dict[str, Any]] = []
-    # and all of its worker processes. Load the config template, which defines a few
-    # services that are necessary to run.
-    supervisord_config = ""
 
     # Upstreams for load-balancing purposes. This dict takes the form of a worker type to the
     # ports of each worker. For example:
@@ -437,7 +419,7 @@ def generate_worker_files(
             )
 
         # Enable the worker in supervisord
-        supervisord_config += SUPERVISORD_PROCESS_CONFIG_BLOCK.format_map(worker_config)
+        worker_descriptors.append(worker_config)
 
         # Add nginx location blocks for this worker's endpoints (if any are defined)
         for pattern in worker_config["endpoint_patterns"]:
@@ -535,10 +517,16 @@ def generate_worker_files(
         "/conf/supervisord.conf.j2",
         "/etc/supervisor/supervisord.conf",
         main_config_path=config_path,
-        worker_config=supervisord_config,
         enable_redis=workers_in_use,
     )
 
+    convert(
+        "/conf/synapse.supervisord.conf.j2",
+        "/etc/supervisor/conf.d/synapse.conf",
+        workers=worker_descriptors,
+        main_config_path=config_path,
+    )
+
     # healthcheck config
     convert(
         "/conf/healthcheck.sh.j2",