implement the topic label registry

[zale144]

Purpose of Changes and their Description

add the topic label registry types and store implementation

Link(s) to Ticket(s) or Issue(s) resolved by this PR

https://linear.app/alloralabs/issue/ENGN-5151/2-epoch-label-registry-types-and-storage

Are these changes tested and documented?

• If tested, please describe how. If not, why tests are not needed.
• If documented, please describe where. If not, describe why docs are not needed.
• Added to Unreleased section of CHANGELOG.md?

Still Left Todo

Fill this out if this is a Draft PR so others can help.

---

Summary by cubic

Implements an epoch-scoped topic label registry with new proto types, KV storage, and simple register/lookup helpers. Preps classification-based topics per ENGN-5151 without integrating mutation flows yet.

• New Features
  • Added TopicLabel and EpochLabelRegistry proto messages; regenerated code.
  • Introduced Keeper KV map topicLabelRegistry keyed by (topic_id, epoch/nonce) with pruning via PruneRecordsAfterRewards.
  • Added APIs: GetEpochLabelRegistry, RegisterEpochLabel (idempotent name→id), GetEpochLabelId, GetEpochLabelName.
  • Added validation and errors (ErrInvalidLabelName) and storage key (TopicLabelRegistryKey).
  • Added tests covering empty registry, id assignment, idempotency, and missing lookups.

^{Written for commit e28ffab. Summary will update on new commits.}

[github-actions]

The latest Buf updates on your PR. Results from workflow Buf Linter / buf (pull_request).

Build	Format	Lint	Breaking	Updated (UTC)
✅ passed	✅ passed	✅ passed	⏩ skipped	Feb 26, 2026, 10:05 AM

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[cubic-dev-ai]

cubic analysis

3 issues found across 7 files

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="x/emissions/proto/emissions/v10/topic.proto">

<violation number="1" location="x/emissions/proto/emissions/v10/topic.proto:116">
P2: According to linked Linear issue ENGN-5151, the registry should be keyed by `(topic_id, nonce)` and must be "compatible with existing epoch-scoped pruning patterns." The existing `Nonce` type uses `int64 block_height`, but this field is `uint64 epoch_id`. Consider using `int64` (or referencing the existing `Nonce` type directly) to ensure compatibility with existing pruning infrastructure, and aligning the field name with `nonce` to match the spec.</violation>
</file>

<file name="x/emissions/keeper/keeper.go">

<violation number="1" location="x/emissions/keeper/keeper.go:5068">
P2: Inconsistent error-checking pattern: the rest of the keeper uses `errors.Is(err, collections.ErrNotFound)` but this function uses `errorsmod.IsOf(err, collections.ErrNotFound)`. Use the established `errors.Is` pattern for consistency and to avoid subtle mismatch risks when errors are wrapped.</violation>
</file>

<file name="x/emissions/keeper/keeper_test.go">

<violation number="1" location="x/emissions/keeper/keeper_test.go:6172">
P2: The outer `newFixture()` call in the test loop is wasteful—every test case internally calls `newFixture()` again and either shadows the passed-in `ctx`/`k` (cases 2–5) or only uses the inner `topicId`/`nonce` (case 1). This creates an unused topic per test run. Simplify by either passing all four fixture values into `tc.run` (and removing the inner `newFixture()` calls), or removing the outer `newFixture()` and letting each test case fully manage its own setup.</violation>
</file>

Linked issue analysis

Linked issue: ENGN-5151: 2. Epoch label registry - types & storage

Status	Acceptance criteria	Notes
✅	Define EpochLabelRegistry keyed by (`topic_id`, `nonce`)	Added proto message and Keeper map keyed by Pair(topicId,nonce)
✅	KV layout and marshal/unmarshal helpers	Added TopicLabelRegistry key and generated proto marshal/unmarshal code
✅	Provide read helpers to fetch registry for (topic, nonce)	GetEpochLabelRegistry and lookup helpers added
✅	Provide write helpers to persist registry (explicit writes only)	RegisterEpochLabel persists registry via topicLabelRegistry.Set
✅	No mutations occur automatically (mutations only on explicit calls)	Get returns default without setting; mutations only via explicit Register or pruning
✅	Compatible with existing epoch-scoped pruning patterns	Prune integrated: pruneTopicLabelRegistry uses Clear and is called in pruning flow
✅	Registry can be stored and retrieved for (topic, nonce) (validated by tests)	Unit tests register labels and verify retrieval and lookups

_{Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review.}

[cubic-dev-ai]

P2: According to linked Linear issue ENGN-5151, the registry should be keyed by (topic_id, nonce) and must be "compatible with existing epoch-scoped pruning patterns." The existing Nonce type uses int64 block_height, but this field is uint64 epoch_id. Consider using int64 (or referencing the existing Nonce type directly) to ensure compatibility with existing pruning infrastructure, and aligning the field name with nonce to match the spec.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At x/emissions/proto/emissions/v10/topic.proto, line 116:

<comment>According to linked Linear issue ENGN-5151, the registry should be keyed by `(topic_id, nonce)` and must be "compatible with existing epoch-scoped pruning patterns." The existing `Nonce` type uses `int64 block_height`, but this field is `uint64 epoch_id`. Consider using `int64` (or referencing the existing `Nonce` type directly) to ensure compatibility with existing pruning infrastructure, and aligning the field name with `nonce` to match the spec.</comment>

<file context>
@@ -105,3 +105,14 @@ message TopicIdWeightPair {
+
+message EpochLabelRegistry {
+  uint64 topic_id = 1;
+  uint64 epoch_id = 2;
+  repeated TopicLabel labels = 3;
+}
</file context>

[cubic-dev-ai]

P2: Inconsistent error-checking pattern: the rest of the keeper uses errors.Is(err, collections.ErrNotFound) but this function uses errorsmod.IsOf(err, collections.ErrNotFound). Use the established errors.Is pattern for consistency and to avoid subtle mismatch risks when errors are wrapped.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At x/emissions/keeper/keeper.go, line 5068:

<comment>Inconsistent error-checking pattern: the rest of the keeper uses `errors.Is(err, collections.ErrNotFound)` but this function uses `errorsmod.IsOf(err, collections.ErrNotFound)`. Use the established `errors.Is` pattern for consistency and to avoid subtle mismatch risks when errors are wrapped.</comment>

<file context>
@@ -5043,3 +5055,124 @@ func (k *Keeper) updateTopicWeightAfterStakeChange(
+) (types.EpochLabelRegistry, error) {
+	registry, err := k.topicLabelRegistry.Get(ctx, collections.Join(topicId, nonce))
+	if err != nil {
+		if errorsmod.IsOf(err, collections.ErrNotFound) {
+			return types.EpochLabelRegistry{
+				TopicId: topicId,
</file context>

Suggested change

	if errorsmod.IsOf(err, collections.ErrNotFound) {
	if errors.Is(err, collections.ErrNotFound) {

[cubic-dev-ai]

P2: The outer newFixture() call in the test loop is wasteful—every test case internally calls newFixture() again and either shadows the passed-in ctx/k (cases 2–5) or only uses the inner topicId/nonce (case 1). This creates an unused topic per test run. Simplify by either passing all four fixture values into tc.run (and removing the inner newFixture() calls), or removing the outer newFixture() and letting each test case fully manage its own setup.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At x/emissions/keeper/keeper_test.go, line 6172:

<comment>The outer `newFixture()` call in the test loop is wasteful—every test case internally calls `newFixture()` again and either shadows the passed-in `ctx`/`k` (cases 2–5) or only uses the inner `topicId`/`nonce` (case 1). This creates an unused topic per test run. Simplify by either passing all four fixture values into `tc.run` (and removing the inner `newFixture()` calls), or removing the outer `newFixture()` and letting each test case fully manage its own setup.</comment>

<file context>
@@ -6061,3 +6062,115 @@ func (s *KeeperTestSuite) TestRemoveTopicFromPreviousTopicWeights() {
+
+	for _, tc := range tests {
+		s.Run(tc.name, func() {
+			ctx, k, _, _ := newFixture()
+			tc.run(ctx, k)
+		})
</file context>