## Summary
Fixes#1081. When the version flagged `is_latest` was soft-deleted, no
other version was promoted, and because `GetCurrentLatestVersion` didn't
filter deleted rows, subsequent publishes with a lower semver never
became latest — leaving `/v0/servers/{name}/versions/latest` permanently
404.
This PR has two parts:
### 1. Code fix — recalculate `is_latest` on every status change
- Recalculate `is_latest` after every status mutation
(`UpdateServerStatus`, `UpdateAllVersionsStatus`, and the inline status
change in `UpdateServer`), in the same transaction that already holds
the per-server advisory lock.
- Winner selection reuses the existing `CompareVersions` logic: highest
non-deleted version gets the flag; if every version is deleted, the
highest deleted version keeps it so admin lookups via
`includeDeleted=true` still resolve the server (important for restore
flows).
- New `SetLatestVersion` DB primitive issues two statements (clear old,
set new) — `idx_unique_latest_per_server` is a non-deferrable unique
partial index, so a single `UPDATE` that flips two rows trips the
constraint.
### 2. One-shot migration — heal servers already affected (no manual SQL
needed)
`014_heal_is_latest.sql` promotes the highest non-deleted version on
every server whose `is_latest` flag is on a deleted row (or absent
entirely). Picker parses `major.minor.patch` numerically and falls back
to `published_at` for non-semver or as a tiebreaker. Heals
`io.github.containers/kubernetes-mcp-server` to `0.0.61` automatically
and catches any other servers silently affected by the original bug,
without hardcoded version numbers.
Picker behavior vs. `CompareVersions`:
- Standard `M.m.p` semver: matches exactly, including the
backport-after-delete case (e.g. published 1.0.1 then 1.0.0 hotfix after
deleting 2.0.0 → picks 1.0.1, not 1.0.0).
- Non-semver: falls through to `published_at DESC`. Reasonable.
- Prereleases (`1.0.0-alpha` vs `1.0.0`): both parse to `(1,0,0)`,
tiebreak by `published_at`. Diverges from `CompareVersions` (which
always says `1.0.0 > 1.0.0-alpha`). Edge case requires (a) server hit by
this bug AND (b) prereleases at the top of the version list. Acceptable;
the publisher can flip it with one `mcp-publisher status` call (which
now triggers proper recalc thanks to part 1).
## Verification
End-to-end curl repro of the exact scenario from the issue, run against
both `main` and this branch:
**Before (main):**
```
publish 1.0.0 → 200
publish 0.0.59 → 200
PATCH .../1.0.0/status {deleted} → 200
GET /versions/latest → 404 ← bug
publish 0.0.60 → 200
GET /versions/latest → 404 ← bug persists, 0.0.60 has isLatest=False
```
**After (this branch):**
```
publish 1.0.0 → 200
publish 0.0.59 → 200
PATCH .../1.0.0/status {deleted} → 200
GET /versions/latest → 200 (0.0.59, isLatest=true)
publish 0.0.60 → 200
GET /versions/latest → 200 (0.0.60, isLatest=true)
```
## Test plan
- [x] Service tests covering: soft-delete latest → next highest active
promoted; the exact #1081 repro end-to-end through the service;
all-versions-deleted still keeps highest addressable for admin;
restore-to-higher-version reclaims latest.
- [x] Migration tests covering: kubernetes-mcp-server scenario (heals to
highest semver); backport scenario (semver beats most-recent-published);
no-is_latest-row defensive case; all-deleted server left untouched;
healthy server left untouched; non-semver versions fall back to
`published_at`.
- [x] Full unit test suite (`./internal/... ./cmd/...`) passes against a
real Postgres.
- [x] `make lint` (0 issues) and `make validate` pass.
- [x] Manual curl repro against a running registry confirms the fix
resolves the failure mode and `main` still reproduces it.
🤖 Generated with [Claude Code](https://claude.com/claude-code)
---------
Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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