Sles 2151 fix race condition flush (#643)

* fix recreating of promises

* warn if metrics will be lost due to race condition and fail

* preserve old behavior of adding global tags with api and extension, not dogstatsd

* format

* use dostatsd if the extension is running but no timestamp is set in metric

* avoid other changes, add only the fix

* typo

Author: alexgallotta

src/metrics/listener.ts

@@ -156,7 +156,9 @@ export class MetricsListener {
         }
         // Only create the processor to submit metrics to the API when a user provides a valid timestamp as
         // Dogstatsd does not support timestamps for distributions.
-        this.currentProcessor = this.createProcessor(this.config, this.apiKey);
+        if (this.currentProcessor === undefined) {
+          this.currentProcessor = this.createProcessor(this.config, this.apiKey);
+        }
         // Add global tags to metrics sent to the API
         if (this.globalTags !== undefined && this.globalTags.length > 0) {
           tags = [...tags, ...this.globalTags];

src/metrics/processor.ts

@@ -1,6 +1,6 @@
 import promiseRetry from "promise-retry";
 
-import { logError, Timer } from "../utils";
+import { logError, logWarning, Timer } from "../utils";
 import { Client } from "./api";
 import { Batcher } from "./batcher";
 import { Metric } from "./model";
@@ -77,6 +77,12 @@ export class Processor {
       } catch {
         // Failed to send metrics, keep the old batch alive if retrying is enabled
         if (this.shouldRetryOnFail) {
+          const metricsReceivedWhileSending = this.batcher.toAPIMetrics();
+          if (metricsReceivedWhileSending.length > 0) {
+            logWarning(
+              `Failed to send metrics to Datadog, retrying at next interval. ${metricsReceivedWhileSending.length} metrics received will be lost`,
+            );
+          }
           this.batcher = oldBatcher;
         }
       }