Setup prometheus metric on server start, not import

Author: yuvipanda

jupyter_server/prometheus/metrics.py

@@ -41,7 +41,6 @@
 from .._version import __version__
 
 SERVER_INFO = Info("jupyter_server_info", "Jupyter Server Version information")
-SERVER_INFO.info({"version": __version__})
 
 __all__ = [
     "HTTP_REQUEST_DURATION_SECONDS",

jupyter_server/serverapp.py

@@ -123,6 +123,7 @@
     AsyncMappingKernelManager,
     MappingKernelManager,
 )
+from jupyter_server.prometheus.metrics import SERVER_INFO
 from jupyter_server.services.sessions.sessionmanager import SessionManager
 from jupyter_server.utils import (
     JupyterServerAuthWarning,
@@ -2696,6 +2697,12 @@ def _init_asyncio_patch() -> None:
                     # prefer Selector to Proactor for tornado + pyzmq
                     asyncio.set_event_loop_policy(WindowsSelectorEventLoopPolicy())
 
+    def init_metrics(self) -> None:
+        """
+        Initialize any prometheus metrics that need to be set up on server startup
+        """
+        SERVER_INFO.info({"version": __version__})
+
     @catch_config_error
     def initialize(
         self,
@@ -2763,6 +2770,7 @@ def initialize(
         self.load_server_extensions()
         self.init_mime_overrides()
         self.init_shutdown_no_activity()
+        self.init_metrics()
         if new_httpserver:
             self.init_httpserver()