Opening a deleted Item loads indefinitely #2822

[mkrueger]

This pull request improves the reliability and user experience of reading documents in Cosmos DB by adding timeout handling, fallback logic, and clearer error messaging. The changes ensure that if a document read operation fails or times out, a fallback query by _rid is attempted, and users receive a more informative error message in the UI when a document cannot be found or retrieved.

Error Handling and Messaging Improvements:

• Added a new localized error message "Item not found or request timed out" to bundle.l10n.json for clearer user feedback when document retrieval fails.
• Updated the error reporting in DocumentSession.read to send a documentError event with the new message when a document cannot be found or read, instead of sending a generic or query error.

Timeouts and Fallback Logic:

• Implemented a 4-second timeout for both the primary document read and the fallback _rid query in DocumentSession, with appropriate logging and error handling for timeouts. [1] [2] [3]
• Added fallback logic: if the primary read fails or times out, a secondary query by _rid is attempted, and detailed logs are generated based on the results.

UI Improvements:

• Enhanced the document panel UI to display a loading state only when appropriate, and to show a user-friendly error message when a document cannot be loaded, such as when it is deleted externally or a timeout occurs.

Fixes #2822

[Copilot]

Pull request overview

This pull request addresses issue #2822 where opening a deleted Cosmos DB item causes indefinite loading. The changes implement timeout handling for document read operations, add fallback logic using _rid queries, and improve error messaging in the UI.

Key Changes

• Added 4-second timeout for document read operations with fallback to _rid query if primary read fails
• Introduced documentError event messaging to properly communicate read failures to the UI instead of using generic query errors
• Enhanced UI to display user-friendly error messages when documents cannot be loaded due to deletion or timeout

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 4 comments.

File	Description
l10n/bundle.l10n.json	Added localized error message "Item not found or request timed out" for clearer user feedback
src/webviews/cosmosdb/Document/DocumentPanel.tsx	Updated loading/error state logic to show appropriate UI when document cannot be loaded
src/cosmosdb/session/DocumentSession.ts	Implemented timeout handling with Promise.race, added fallback _rid query, and changed error reporting to use documentError events

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[Copilot]

@mkrueger I've opened a new pull request, #2858, to work on those changes. Once the pull request is ready, I'll request review from you.

[Copilot]

Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

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[Copilot]

@mkrueger I've opened a new pull request, #2864, to work on those changes. Once the pull request is ready, I'll request review from you.

[Copilot]

Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

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[Copilot]

The telemetry properties are set after the documentError event is sent, which means the error information won't be included in the telemetry context that gets logged. This telemetry assignment should happen before the postMessage call to ensure the error details are captured in the telemetry.

Suggested change

	await this.channel.postMessage({
	type: 'event',
	name: 'documentError',
	params: [this.id, errorMessage],
	});
	// Still log telemetry but don't use errorHandling which sends queryError
	context.telemetry.properties.error = errorMessage;
	// Still log telemetry but don't use errorHandling which sends queryError
	context.telemetry.properties.error = errorMessage;
	await this.channel.postMessage({
	type: 'event',
	name: 'documentError',
	params: [this.id, errorMessage],
	});