Show CPU indicator widget only if available

jtpio · Apr 6, 2020 · 4a1ddd1 · 4a1ddd1
1 parent 91d5750
commit 4a1ddd1
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Showing 2 changed files with 13 additions and 3 deletions.
diff --git a/packages/system-monitor-base/src/model.ts b/packages/system-monitor-base/src/model.ts
@@ -64,6 +64,14 @@ export namespace ResourceUsage {
       });
     }
 
+    /**
+     * A promise that resolves after the next request.
+     */
+    async refresh(): Promise<void> {
+      await this._poll.refresh();
+      await this._poll.tick;
+    }
+
     /**
      * Whether the memory metric is available.
      */

diff --git a/packages/system-monitor/src/index.ts b/packages/system-monitor/src/index.ts
@@ -69,10 +69,12 @@ const extension: JupyterFrontEndPlugin<void> = {
     }
 
     const model = new ResourceUsage.Model({ refreshRate });
-    const cpu = CpuView.createCpuView(model, cpuLabel);
+    await model.refresh();
+    if (model.cpuAvailable) {
+      const cpu = CpuView.createCpuView(model, cpuLabel);
+      topBar.addItem('cpu', cpu);
+    }
     const memory = MemoryView.createMemoryView(model, memoryLabel);
-
-    topBar.addItem('cpu', cpu);
     topBar.addItem('memory', memory);
   },
 };