add no-clusters option on metrics query

bin/src/cli.rs

@@ -220,6 +220,11 @@ pub enum MetricsCmd {
             // parse(try_from_str = split_slash)
         )]
         backends: Vec<String>,
+        #[clap(
+            long = "no-clusters",
+            help = "get only the metrics of main process and workers (no cluster metrics)"
+        )]
+        no_clusters: bool,
     },
 }
 

bin/src/ctl/command.rs

@@ -176,12 +176,14 @@ impl CommandManager {
         metric_names: Vec<String>,
         cluster_ids: Vec<String>,
         backend_ids: Vec<String>,
+        no_clusters: bool,
     ) -> Result<(), anyhow::Error> {
         let request: Request = RequestType::QueryMetrics(QueryMetricsOptions {
             list,
             cluster_ids,
             backend_ids,
             metric_names,
+            no_clusters,
         })
         .into();
 

bin/src/ctl/mod.rs

@@ -78,7 +78,8 @@ impl CommandManager {
                     names,
                     clusters,
                     backends,
-                } => self.get_metrics(list, refresh, names, clusters, backends),
+                    no_clusters,
+                } => self.get_metrics(list, refresh, names, clusters, backends, no_clusters),
                 _ => self.configure_metrics(cmd),
             },
             SubCmd::Logging { level } => self.logging_filter(&level),

command/src/command.proto

@@ -412,6 +412,8 @@ message QueryMetricsOptions {
     repeated string backend_ids = 3;
     // query only these metrics
     repeated string metric_names = 4;
+    // query only worker and main process metrics (no cluster metrics)
+    required bool no_clusters = 5;
 }
 
 // options to configure metrics collection

lib/src/metrics/local_drain.rs

@@ -257,12 +257,21 @@ impl LocalDrain {
             cluster_ids,
             backend_ids,
             list,
+            no_clusters,
         } = options;
 
         if *list {
             return self.list_all_metric_names();
         }
 
+        if *no_clusters {
+            let proxy_metrics = self.dump_proxy_metrics(metric_names);
+            return Ok(ContentType::WorkerMetrics(WorkerMetrics {
+                proxy: proxy_metrics,
+                clusters: BTreeMap::new(),
+            }).into());
+        }
+
         let worker_metrics = match (cluster_ids.is_empty(), backend_ids.is_empty()) {
             (false, _) => self.query_clusters(cluster_ids, metric_names)?,
             (true, false) => self.query_backends(backend_ids, metric_names)?,