fix(samples): filter out heartbeat messages from webhook stream UI

[pengying]

Co-Authored-By: Claude Opus 4.6 noreply@anthropic.com

Ignore heartbeat messages in the webhook stream event handler to prevent them from being processed as regular webhook events.

[pengying]

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• fix(samples): filter out heartbeat messages from webhook stream UI #198 👈 (View in Graphite)
• feat(samples): add TypeScript backend using Grid TypeScript SDK #197
• feat: adding kotlin sample #192
• main

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[greptile-apps]

Greptile Summary

This PR filters out heartbeat messages from the SSE webhook stream in the WebhookStream component, preventing them from being surfaced as events in the UI.

Key changes:

• Adds an early-exit guard (raw === 'heartbeat' or empty string) on line 23, cleanly filtering heartbeat frames before any JSON parsing.
• Silently discards all non-JSON payloads in the catch block (lines 32-34).
• Parses the trimmed string (raw) directly instead of event.data.

The implementation correctly achieves its stated goal. One minor issue: the catch block's comment mentions "heartbeats" but these are already filtered by the guard on line 23, making the comment slightly misleading.

Confidence Score: 4/5

• Safe to merge — the heartbeat filtering logic is correct and focused. One minor comment clarity issue remains.
• The change correctly achieves its goal of filtering heartbeat messages with a simple, early-exit guard. The logic is sound and the happy path is clean. The only concern is a misleading comment on the catch block that should be clarified to accurately reflect what the code does. This is a trivial fix and does not affect functional correctness.
• Comment clarification needed in samples/frontend/src/components/WebhookStream.tsx (lines 32-34)

_{Last reviewed commit: 8bb2c10}

[greptile-apps]

The comment mentions "heartbeats" but they are already filtered by the raw === 'heartbeat' check on line 23, so they never reach this catch block. Consider updating the comment to clarify:

Suggested change

	} catch {
	setEvents((prev) => [{
	timestamp: Date.now(),
	type: 'raw',
	raw: event.data
	}, ...prev])
	// Skip non-JSON messages (heartbeats, etc.)
	}
	} catch {
	// Discard unparseable SSE frames
	}

Prompt To Fix With AI

This is a comment left during a code review.
Path: samples/frontend/src/components/WebhookStream.tsx
Line: 32-34

Comment:
The comment mentions "heartbeats" but they are already filtered by the `raw === 'heartbeat'` check on line 23, so they never reach this catch block. Consider updating the comment to clarify:

```suggestion
        } catch {
          // Discard unparseable SSE frames
        }
```

How can I resolve this? If you propose a fix, please make it concise.

_{Note: If this suggestion doesn't match your team's coding style, reply to this and let me know. I'll remember it for next time!}