Upgrade Prometheus client

docs/generate-metrics.py

@@ -22,8 +22,12 @@ class Generator:
         for name in dir(jupyterhub.metrics):
             obj = getattr(jupyterhub.metrics, name)
             if obj.__class__.__module__.startswith('prometheus_client.'):
-                for metric in obj.describe():
-                    table_rows.append([metric.type, metric.name, metric.documentation])
+                description = obj.describe()[0]
+                table_rows.append([
+                    description.type,
+                    description.name,
+                    description.documentation,
+                ])
         return table_rows
 
     def prometheus_metrics(self):

jupyterhub/tests/test_metrics.py

@@ -11,14 +11,15 @@ from .utils import add_user, api_request, get_page
 
 
 @pytest.mark.parametrize(
-    "metric, expected_metric_name",
+    "metric, expected_name",
     [
         (metrics.TOTAL_USERS, 'jupyterhub_total_users'),
         (metrics.REQUEST_DURATION_SECONDS, 'jupyterhub_request_duration_seconds'),
     ],
 )
-def test_metrics_prefix(metric, expected_metric_name):
-    assert metric._name == expected_metric_name
+def test_metrics_prefix(metric, expected_name):
+    description = metric.describe()[0]
+    assert description.name == expected_name
 
 
 async def test_total_users(app):

requirements.txt

@@ -7,7 +7,7 @@ jupyter_telemetry>=0.1.0
 oauthlib>=3.0
 packaging
 pamela; sys_platform != 'win32'
-prometheus_client>=0.4.0
+prometheus_client>=0.5.0
 psutil>=5.6.5; sys_platform == 'win32'
 python-dateutil
 requests