Use Helix ListFiles endpoint to work around dnceng#6072

[lewing]

Summary

Work around dotnet/dnceng#6072 in the CI analysis skill by using the Helix \ListFiles\ endpoint instead of file URIs from the \Details\ endpoint.

Problem

The Helix work item Details API (\GET .../workitems/{id}) has two bugs in its \Files[].Uri\ values:

1. Subdirectory flattening: Files uploaded from subdirectories (e.g. \xharness-output/logs/test/build.binlog) get URIs with only the base filename (.../files/build.binlog), so multiple distinct files with the same base name collide
2. Unicode rejection: The /files/{name}\ endpoint validates against an ASCII-only regex, rejecting filenames containing unicode characters (e.g. CJK test directory names like \鿀蜒枛遫䡫煉)

The previous workaround reconstructed permalink URIs from the \FileName\ field, but this still routed through the broken /files/\ endpoint which rejects unicode.

Fix

Use the separate \ListFiles\ endpoint (\GET .../workitems/{id}/files) which returns direct blob storage URIs. These URIs:

• Preserve full subdirectory paths
• Have properly percent-encoded unicode
• Don't route through the permalink/regex validation layer

Verified against PR #124125 CI artifacts: 53 files with unicode paths all return HTTP 200 via ListFiles blob URIs, vs broken/colliding URIs from the Details endpoint.

[Copilot]

Pull request overview

Updates the CI analysis skill’s Helix artifact retrieval to avoid broken file URIs returned by the Helix work item Details endpoint (dnceng#6072), switching to the ListFiles endpoint to obtain direct blob storage links that preserve subdirectories and support unicode filenames.

Changes:

• Add Get-HelixWorkItemFiles to call the Helix .../workitems/{name}/files (ListFiles) endpoint.
• Replace Files from the Details response with ListFiles results (Name/Link → FileName/Uri).
• Update the Helix artifacts reference doc to describe the new workaround and the unicode/subdirectory issues.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
.github/skills/ci-analysis/scripts/Get-CIStatus.ps1	Adds ListFiles retrieval and swaps the work item Files list to use blob URIs.
.github/skills/ci-analysis/references/helix-artifacts.md	Updates documentation to describe the ListFiles-based workaround and the underlying Helix bug behavior.

Comments suppressed due to low confidence (1)

.github/skills/ci-analysis/scripts/Get-CIStatus.ps1:1383

• Get-HelixWorkItemDetails builds the Details URL using $WorkItemName without URL-encoding, while Get-HelixWorkItemFiles correctly uses EscapeDataString. If a work item name contains characters that must be escaped (spaces, +, #, unicode, etc.), the Details request can fail or target the wrong resource. Encode the work item segment the same way as in Get-HelixWorkItemFiles (ideally compute once and reuse for both endpoints).

    $url = "https://helix.dot.net/api/2019-06-17/jobs/$JobId/workitems/$WorkItemName"

[lewing]

Also opened AzDO PR #57709 to fix the server-side bug in dotnet-helix-service (dotnet/dnceng#6072). That fix passes FileName through to the permalink constructor and replaces the ASCII-only regex with a path traversal check to allow unicode.