Web: Fix crash that happens when the app receives an unknown message

[laurent22]

For example, extensions can send messages which would crash the app because those messages may not have the .kind property

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

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Reviewing files that changed from the base of the PR and between 7b5111d and 0b7e43c.

📒 Files selected for processing (1)

• packages/app-mobile/utils/ipc/RNToWebViewMessenger.ts

🚧 Files skipped from review as they are similar to previous changes (1)

• packages/app-mobile/utils/ipc/RNToWebViewMessenger.ts

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📝 Walkthrough

Walkthrough

The RNToWebViewMessenger.onWebViewMessage method now normalises incoming event payloads into a single data value (using event.nativeEvent.data directly when canUseOptimizedPostMessage is true, otherwise attempting JSON.parse). It logs and returns on parse failure, and only forwards messages when data is a non-null object with a string kind property; logging uses a module-level logger.

Changes

Cohort / File(s)	Summary
Message validation and logging packages/app-mobile/utils/ipc/RNToWebViewMessenger.ts	Normalises incoming payload into data (optimised postMessage vs JSON.parse), catches and logs JSON parse failures and returns early, validates data is a non-null object with a string kind before calling this.onMessage(data), and introduces a module-level Logger.create('RNToWebViewMessenger') instance for logs.

Suggested labels

mobile, bug

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Important

Pre-merge checks failed

Please resolve all errors before merging. Addressing warnings is optional.

❌ Failed checks (1 error)

Check name	Status	Explanation	Resolution
Pr Description Must Follow Guidelines	❌ Error	The pull request description lacks a high-level explanation of the solution approach and omits test plan or verification steps, violating Joplin contribution guidelines.	Expand the PR description to include the solution approach, concrete test plan, and verification steps to make it self-contained and reviewable.

✅ Passed checks (3 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly and specifically describes the main change: fixing a crash caused by unknown messages, which aligns with the changeset that adds validation and error handling for incoming payloads.
Description check	✅ Passed	The description is directly related to the changeset, explaining the specific problem (extensions sending messages without .kind property) that the changes address.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch webapp_unknown_message

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[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Inline comments:
In `@packages/app-mobile/utils/ipc/RNToWebViewMessenger.ts`:
- Around line 47-52: The JSON.parse call in RNToWebViewMessenger.ts can throw
for non-JSON payloads before the kind/type guard runs; wrap the non-web branch
parse in a try/catch (or otherwise validate the string) so malformed JSON
doesn't crash: when canUseOptimizedPostMessage is false, attempt
JSON.parse(event.nativeEvent.data) inside a try block, on failure log the raw
payload via logger.info or logger.warn and return early, and only call
this.onMessage(data) when parsing succeeded and the existing typeof data ===
'object' && data !== null && typeof data.kind === 'string' check passes.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

Plan: Pro

Run ID: 07b91077-9efb-4222-9992-3c0f48ff313b

📥 Commits

Reviewing files that changed from the base of the PR and between fc212d0 and 7b5111d.

📒 Files selected for processing (1)

• packages/app-mobile/utils/ipc/RNToWebViewMessenger.ts