Create healthcheck script for synapse-workers container (#11429)

The intent is to iterate through all the worker ports and only
report healthy when all are healthy, starting with the main process.

1 files changed, 13 insertions, 0 deletions

diff --git a/docker/configure_workers_and_start.py b/docker/configure_workers_and_start.py
index f4ac1c22a4..adbb551cee 100755
--- a/docker/configure_workers_and_start.py
+++ b/docker/configure_workers_and_start.py
@@ -474,10 +474,16 @@ def generate_worker_files(environ, config_path: str, data_dir: str):
 
     # Determine the load-balancing upstreams to configure
     nginx_upstream_config = ""
+
+    # At the same time, prepare a list of internal endpoints to healthcheck
+    # starting with the main process which exists even if no workers do.
+    healthcheck_urls = ["http://localhost:8080/health"]
+
     for upstream_worker_type, upstream_worker_ports in nginx_upstreams.items():
         body = ""
         for port in upstream_worker_ports:
             body += "    server localhost:%d;\n" % (port,)
+            healthcheck_urls.append("http://localhost:%d/health" % (port,))
 
         # Add to the list of configured upstreams
         nginx_upstream_config += NGINX_UPSTREAM_CONFIG_BLOCK.format(
@@ -510,6 +516,13 @@ def generate_worker_files(environ, config_path: str, data_dir: str):
         worker_config=supervisord_config,
     )
 
+    # healthcheck config
+    convert(
+        "/conf/healthcheck.sh.j2",
+        "/healthcheck.sh",
+        healthcheck_urls=healthcheck_urls,
+    )
+
     # Ensure the logging directory exists
     log_dir = data_dir + "/logs"
     if not os.path.exists(log_dir):