🐛 Fixed "linked comment is no longer available" error after unhiding a comment

[luissazevedo]

Problem

Unhiding a comment in admin and then using "View on post" can land on the post with the comments section showing "The linked comment is no longer available." instead of scrolling to the comment.

The permalink flow in comments-ui (fetchScrollTarget) loads the target via GET /api/members/comments/:id/ and requires status === 'published'. On hosts that cache the members API at the edge (purged via the X-Cache-Invalidate header), every comment mutation purged only:

• /api/members/comments/post/<postId>/
• /api/members/comments/<parentId>/replies/

…but never the single-comment read path. So after unhiding, /api/members/comments/:id/ kept serving the stale "hidden" payload (while the freshly-purged browse path rendered the comment right below the error). The reverse direction is worse: after hiding a comment, the cached read endpoint kept serving its content until TTL.

These purge paths predate the permalink feature (added Dec 2025 in 3df0e8c), which introduced the dependency on the read endpoint — closest precedent is a489d5a, which added the /replies/ path for the same reason.

Solution

• setCacheInvalidationHeaders now also emits /api/members/comments/<id>/ (appended last, so existing unanchored matchers stay valid)
• Replaced the six duplicated inline copies of the purge-path logic (member edit, add, like, unlike, dislike, undislike) with calls to the existing shared helper — net −9 lines
• Updated header assertions, added a unit test for the top-level case, regenerated snapshots; sites where the header now contains a dynamically-created comment id use stringMatching so snapshots stay stable across runs

Note for review: this only requests the purge — worth confirming with the Pro team that the edge purge rules cover /api/members/comments/:id/ (they should if matching is prefix-based on /api/members/comments/).

Local verification: test/unit/server/services/comments (39 passing), test/e2e-api/members-comments (102 passing, twice — no snapshot drift), test/e2e-api/admin/comments.test.js (88 passing), test/e2e-api/admin/member-commenting.test.js (30 passing).

Replaces #28492 (same commit, recreated from an in-repo branch instead of a fork).

🤖 Generated with Claude Code

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

Plan: Pro

Run ID: 2c0580db-a609-407f-b839-bfea3d25d882

📥 Commits

Reviewing files that changed from the base of the PR and between d180686 and 29f10e7.

⛔ Files ignored due to path filters (2)

• ghost/core/test/e2e-api/admin/__snapshots__/comments.test.js.snap is excluded by !**/*.snap
• ghost/core/test/e2e-api/members-comments/__snapshots__/comments.test.js.snap is excluded by !**/*.snap

📒 Files selected for processing (4)

• ghost/core/core/server/services/comments/comments-controller.js
• ghost/core/test/e2e-api/admin/comments.test.js
• ghost/core/test/e2e-api/members-comments/comments.test.js
• ghost/core/test/unit/server/services/comments/comments-controller.test.js

---

Walkthrough

This PR refactors cache-invalidation header construction in the comments controller from duplicated per-method logic to a centralized setCacheInvalidationHeaders() helper. The invalidation paths are expanded to include the specific mutated comment endpoint (/api/members/comments/${model.id}/) alongside existing post and reply paths. All comment mutation endpoints (edit, add, like, unlike, dislike, undislike) are updated to call the helper. Unit tests are updated with explicit comment IDs in fixtures and expanded header expectations, including a new test for top-level comment invalidation. Admin and member E2E tests are updated to assert the broader cache-invalidation behavior across hide, pin, like, dislike, and edit operations.

Possibly related PRs

• TryGhost/Ghost#28020: Modifies dislike/undislike flow and X-Cache-Invalidate header logic in the same comments controller.
• TryGhost/Ghost#28297: Changes how cache-invalidation paths are computed in comments controller mutation flows and updated in test assertions.

Suggested labels

community

Suggested reviewers

• kevinansfield

🚥 Pre-merge checks | ✅ 4

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly summarizes the primary bug fix: addressing the 'linked comment is no longer available' error after unhiding comments, which directly matches the changeset's core objective.
Description check	✅ Passed	The description thoroughly explains the problem, root cause (missing single-comment cache purge path), and the solution implemented in the changeset, with verification details.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ 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 fix-comment-read-cache-invalidation

Warning

There were issues while running some tools. Please review the errors and either fix the tool's configuration or disable the tool if it's a critical failure.

🔧 ast-grep (0.43.0)

ghost/core/test/e2e-api/admin/comments.test.js

ghost/core/test/e2e-api/members-comments/comments.test.js

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands and usage tips.}