Merge pull request #5565 from matrix-org/rav/docker/fix_log_config

Docker: generate our own log config

changelog.d/5565.feature

@@ -0,0 +1 @@
+Docker: Send synapse logs to the docker logging system, by default.

docker/README.md

@@ -186,6 +186,8 @@ The following environment variables are supported in this mode:
 * `SYNAPSE_REPORT_STATS` (mandatory, `yes` or `no`): whether to enable
   anonymous statistics reporting.
 * `SYNAPSE_CONFIG_PATH` (mandatory): path to the file to be generated.
+* `SYNAPSE_CONFIG_DIR`: where additional config files (such as the log config
+  and event signing key) will be stored. Defaults to `/data`.
 * `SYNAPSE_DATA_DIR`: where the generated config will put persistent data
   such as the datatase and media store. Defaults to `/data`.
 * `UID`, `GID`: the user id and group id to use for creating the data

docker/start.py

@@ -135,8 +135,16 @@ def run_generate_config(environ, ownership):
         if v not in environ:
             error("Environment variable '%s' is mandatory in `generate` mode." % (v,))
 
+    server_name = environ["SYNAPSE_SERVER_NAME"]
+    config_dir = environ.get("SYNAPSE_CONFIG_DIR", "/data")
     data_dir = environ.get("SYNAPSE_DATA_DIR", "/data")
 
+    # create a suitable log config from our template
+    log_config_file = "%s/%s.log.config" % (config_dir, server_name)
+    if not os.path.exists(log_config_file):
+        log("Creating log config %s" % (log_config_file,))
+        convert("/conf/log.config", log_config_file, environ)
+
     # make sure that synapse has perms to write to the data dir.
     subprocess.check_output(["chown", ownership, data_dir])
 
@@ -145,11 +153,13 @@ def run_generate_config(environ, ownership):
         "-m",
         "synapse.app.homeserver",
         "--server-name",
-        environ["SYNAPSE_SERVER_NAME"],
+        server_name,
         "--report-stats",
         environ["SYNAPSE_REPORT_STATS"],
         "--config-path",
         environ["SYNAPSE_CONFIG_PATH"],
+        "--config-directory",
+        config_dir,
         "--data-directory",
         data_dir,
         "--generate-config",