fix(processor/logdedup): Update shutdown behaviour (open-telemetry#34563

)

**Description:** <Describe what has changed.>
Simplifies the processor shutdown behaviour by removing the unnecessary
done channel.

**Link to tracking Issue:**

- open-telemetry#34478 

**Testing:**

Updated unit test verifying shutdown behaviour.

**Documentation:**

N/A

.chloggen/logdedup-shutdown.yaml

@@ -0,0 +1,27 @@
+# Use this changelog template to create an entry for release notes.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: enhancement
+
+# The name of the component, or a single word describing the area of concern, (e.g. filelogreceiver)
+component: logdedupprocessor
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Simplifies the processor shutdown behaviour by removing the unnecessary done channel.
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [34478]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:
+
+# If your change doesn't affect end users or the exported elements of any package,
+# you should instead start your pull request title with [chore] or use the "Skip Changelog" label.
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: [user]

processor/logdeduplicationprocessor/processor.go

@@ -62,23 +62,13 @@ func (p *logDedupProcessor) Capabilities() consumer.Capabilities {
 }
 
 // Shutdown stops the processor.
-func (p *logDedupProcessor) Shutdown(ctx context.Context) error {
+func (p *logDedupProcessor) Shutdown(_ context.Context) error {
 	if p.cancel != nil {
+		// Call cancel to stop the export interval goroutine and wait for it to finish.
 		p.cancel()
-	}
-
-	doneChan := make(chan struct{})
-	go func() {
-		defer close(doneChan)
 		p.wg.Wait()
-	}()
-
-	select {
-	case <-ctx.Done():
-		return ctx.Err()
-	case <-doneChan:
-		return nil
 	}
+	return nil
 }
 
 // ConsumeLogs processes the logs.
@@ -117,6 +107,9 @@ func (p *logDedupProcessor) handleExportInterval(ctx context.Context) {
 	for {
 		select {
 		case <-ctx.Done():
+			if err := ctx.Err(); err != context.Canceled {
+				p.logger.Error("context error", zap.Error(err))
+			}
 			return
 		case <-ticker.C:
 			p.mux.Lock()

processor/logdeduplicationprocessor/processor_test.go

@@ -92,19 +92,11 @@ func TestProcessorShutdownCtxError(t *testing.T) {
 	p, err := newProcessor(cfg, logsSink, logger)
 	require.NoError(t, err)
 
-	// We don't call p.Start as it can create a non-deterministic situation in Shutdown where we may not exit due to ctx error
-
-	// Create empty cancel func as this is called during shutdown
-	p.cancel = func() {}
-
-	// Add one to wait group to ensure shutdown blocks and the ctx error will trigger
-	p.wg.Add(1)
-
+	// Start then stop the processor checking for errors
+	err = p.Start(ctx, componenttest.NewNopHost())
+	require.NoError(t, err)
 	err = p.Shutdown(ctx)
-	require.ErrorIs(t, err, context.Canceled)
-
-	// Call done to ensure goroutine spawned in Shutdown doesn't leak
-	p.wg.Done()
+	require.NoError(t, err)
 }
 
 func TestProcessorCapabilities(t *testing.T) {