Add event source for stats

src/middlewared/middlewared/plugins/apps/stats.py

@@ -0,0 +1,35 @@
+import time
+
+from middlewared.event import EventSource
+from middlewared.schema import Dict, Int, Str
+from middlewared.service import CallError
+from middlewared.validators import Range
+
+from .ix_apps.docker.stats import list_resources_stats_by_project
+
+
+class AppStatsEventSource(EventSource):
+
+    """
+    Retrieve statistics of apps.
+    """
+    ACCEPTS = Dict(
+        Int('interval', default=2, validators=[Range(min_=2)]),
+    )
+    RETURNS = Dict(
+        Str('data', required=True),
+        Str('timestamp', required=True, null=True)
+    )
+
+    def run_sync(self):
+        if not self.middleware.call_sync('docker.state.validate', False):
+            raise CallError('Apps are not available')
+
+        interval = self.arg['interval']
+        while not self._cancel_sync.is_set():
+            self.send_event('ADDED', fields=list_resources_stats_by_project())
+            time.sleep(interval)
+
+
+def setup(middleware):
+    middleware.register_event_source('app.stats', AppStatsEventSource, roles=['APPS_READ'])