Investigation: Issue #497 duplicate large blobs is fixed in upstream DurableTask.AzureStorage

[Copilot]

Summary

What changed?

Investigation determined that issue #497 ("Duplicate large blobs created for orchestrations with large inputs/outputs") has already been fixed upstream in DurableTask.AzureStorage.

Why is this change needed?

No code changes required. The issue was in the upstream DurableTask.AzureStorage library, not in this repository:

• PR Fix wrong blob URL on orchestration inputs durabletask#817 (merged Nov 2022) fixed duplicate blob creation by implementing deterministic blob naming
• GetNewLargeMessageBlobName now uses instanceId, activityId, and eventType to generate unique, repeatable names
• This extension already uses DurableTask.AzureStorage v2.7.1 which includes the fix

Issues / work items

• Related Duplicate large blobs created for orchestrations with large inputs/outputs #497

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Project checklist

• Documentation changes are not required
• Release notes are not required for the next release
• Backport is not required
• All required tests have been added/updated (unit tests, E2E tests)
• No extra work is required to be leveraged by OutOfProc SDKs
• No change to the version of the WebJobs.Extensions.DurableTask package
• No EventIds were added to EventSource logs
• This change should be added to the v2.x branch
• Breaking change?

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AI-assisted code disclosure (required)

Was an AI tool used? (select one)

• No
• Yes, AI helped write parts of this PR (e.g., GitHub Copilot)
• Yes, an AI agent generated most of this PR

If AI was used:

• Tool(s): GitHub Copilot
• AI-assisted areas/files: Investigation and analysis only; no code changes
• What you changed after AI output: N/A - investigation only

AI verification (required if AI was used):

• I understand the code and can explain it
• I verified referenced APIs/types exist and are correct
• I reviewed edge cases/failure paths (timeouts, retries, cancellation, exceptions)
• I reviewed concurrency/async behavior
• I checked for unintended breaking or behavior changes

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Testing

Automated tests

• Result: N/A - no code changes

Manual validation (only if runtime/behavior changed)

• N/A - investigation only

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Notes for reviewers

• Issue Duplicate large blobs created for orchestrations with large inputs/outputs #497 can be closed as resolved
• The "dtfx" label correctly indicates this was an upstream DurableTask Framework issue

Warning

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• https://api.github.com/repos/Azure/durabletask/pulls/216/comments
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Original prompt

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This section details on the original issue you should resolve

<issue_title>Duplicate large blobs created for orchestrations with large inputs/outputs</issue_title>
<issue_description>This was discovered while debugging some new tests that were written in the purge history PR (which includes large message cleanup): Azure/durabletask#216 (comment).</issue_description>

<agent_instructions>check if this issue still exists, if so fix it</agent_instructions>

Comments on the Issue (you are @copilot in this section)

• Fixes Duplicate large blobs created for orchestrations with large inputs/outputs #497

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