refactor(consumer): lift framework to core/consumer with domain topickey packages

Move the shared queue consumer framework to top-level core/consumer so both
SubmitQueue and Stovepipe can reuse it. Pipeline stage constants now live in
per-domain submitqueue/core/topickey and stovepipe/core/topickey packages.

Author: mnoah1

CLAUDE.md

@@ -147,7 +147,8 @@ Paths follow the directory layout: shared code is top-level, domain code nests u
 - Proto (generated): `github.com/uber/submitqueue/{domain}/{service}/protopb`
 - Domain entities: `github.com/uber/submitqueue/{domain}/entity` (e.g. `.../submitqueue/entity`)
 - Domain extensions: `github.com/uber/submitqueue/{domain}/extension/{ext}[/{impl}]` (e.g. `.../submitqueue/extension/storage/mysql`)
-- Domain-internal infra: `github.com/uber/submitqueue/{domain}/core/{pkg}` (e.g. `.../submitqueue/core/consumer`, `.../submitqueue/core/request`)
+- Cross-domain consumer framework: `github.com/uber/submitqueue/core/consumer`; domain pipeline topic keys: `github.com/uber/submitqueue/{domain}/core/topickey`
+- Domain-internal infra: `github.com/uber/submitqueue/{domain}/core/{pkg}` (e.g. `.../submitqueue/core/request`)
 - Shared entities: `github.com/uber/submitqueue/entity/{name}` (e.g. `.../entity/messagequeue`)
 - Shared extensions: `github.com/uber/submitqueue/extension/{name}` (e.g. `.../extension/messagequeue`)
 - Cross-domain infra: `github.com/uber/submitqueue/core/{pkg}` (e.g. `.../core/errs`, `.../core/metrics`)

Makefile

@@ -336,7 +336,7 @@ local-stovepipe-gateway-start: build-stovepipe-gateway-linux ## Start Stovepipe
 
 mocks: ## Generate mock files using mockgen
 	@echo "Generating mocks..."
-	@$(BAZEL) run @rules_go//go -- generate ./submitqueue/extension/storage/... ./submitqueue/extension/buildrunner/... ./submitqueue/extension/changeprovider/... ./extension/counter/... ./extension/messagequeue/... ./submitqueue/extension/queueconfig/... ./submitqueue/extension/mergechecker/... ./submitqueue/extension/pusher/... ./submitqueue/extension/scorer/... ./submitqueue/extension/conflict/... ./submitqueue/core/consumer/...
+	@$(BAZEL) run @rules_go//go -- generate ./submitqueue/extension/storage/... ./submitqueue/extension/buildrunner/... ./submitqueue/extension/changeprovider/... ./extension/counter/... ./extension/messagequeue/... ./submitqueue/extension/queueconfig/... ./submitqueue/extension/mergechecker/... ./submitqueue/extension/pusher/... ./submitqueue/extension/scorer/... ./submitqueue/extension/conflict/... ./core/consumer/...
 	@echo "Mocks generated successfully!"
 
 proto: ## Generate protobuf files from .proto definitions

submitqueue/core/consumer/BUILD.bazel core/consumer/BUILD.bazelsubmitqueue/core/consumer/BUILD.bazel renamed to core/consumer/BUILD.bazel

@@ -7,7 +7,7 @@ go_library(
         "controller.go",
         "registry.go",
     ],
-    importpath = "github.com/uber/submitqueue/submitqueue/core/consumer",
+    importpath = "github.com/uber/submitqueue/core/consumer",
     visibility = ["//visibility:public"],
     deps = [
         "//core/errs",
@@ -27,11 +27,12 @@ go_test(
     ],
     deps = [
         ":consumer",
+        "//core/consumer/mock",
         "//core/errs",
         "//entity/messagequeue",
         "//extension/messagequeue",
         "//extension/messagequeue/mock",
-        "//submitqueue/core/consumer/mock",
+        "//submitqueue/core/topickey",
         "@com_github_stretchr_testify//assert",
         "@com_github_stretchr_testify//require",
         "@com_github_uber_go_tally//:tally",

submitqueue/core/consumer/README.md core/consumer/README.mdsubmitqueue/core/consumer/README.md renamed to core/consumer/README.md

@@ -26,7 +26,7 @@ The top-level orchestrator. Register controllers, start consuming, and stop grac
 
 ```go
 registry, _ := consumer.NewTopicRegistry([]consumer.TopicConfig{
-    {Key: consumer.TopicKeyStart, Name: "request", Queue: q, Subscription: subConfig},
+    {Key: topickey.TopicKeyStart, Name: "request", Queue: q, Subscription: subConfig},
 })
 
 c := consumer.New(logger, scope, registry,
@@ -71,21 +71,21 @@ The `TopicRegistry` maps topic keys to queue backends, topic names, and subscrip
 ```go
 registry, _ := consumer.NewTopicRegistry([]consumer.TopicConfig{
     {
-        Key:          consumer.TopicKeyStart,
+        Key:          topickey.TopicKeyStart,
         Name:         "request",
         Queue:        q,
         Subscription: extqueue.DefaultSubscriptionConfig("worker-1", "orchestrator"),
     },
     {
-        Key:   consumer.TopicKeyBuild,
+        Key:   topickey.TopicKeyBuild,
         Name:  "build",
         Queue: q,
         // No Subscription — publish-only topic
     },
 })
 ```
 
-**Topic keys** are fixed identifiers for pipeline stages (e.g., `TopicKeyStart`, `TopicKeyBuild`). The actual queue topic name is configured separately, so library consumers can use their own naming conventions.
+**Topic keys** are fixed identifiers for pipeline stages (e.g., `TopicKeyStart`, `TopicKeyBuild`). Constants live in each domain's `core/topickey` package; this package defines only the `TopicKey` type and registry machinery. The actual queue topic name is configured separately, so library consumers can use their own naming conventions.
 
 ## Error Handling
 

submitqueue/core/consumer/consumer.go core/consumer/consumer.gosubmitqueue/core/consumer/consumer.go renamed to core/consumer/consumer.go

@@ -23,15 +23,17 @@ import (
 	"testing"
 	"time"
 
+	"github.com/uber/submitqueue/submitqueue/core/topickey"
+
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	"github.com/uber-go/tally"
+	"github.com/uber/submitqueue/core/consumer"
+	consumermock "github.com/uber/submitqueue/core/consumer/mock"
 	"github.com/uber/submitqueue/core/errs"
 	entityqueue "github.com/uber/submitqueue/entity/messagequeue"
 	extqueue "github.com/uber/submitqueue/extension/messagequeue"
 	queuemock "github.com/uber/submitqueue/extension/messagequeue/mock"
-	"github.com/uber/submitqueue/submitqueue/core/consumer"
-	consumermock "github.com/uber/submitqueue/submitqueue/core/consumer/mock"
 	"go.uber.org/mock/gomock"
 	"go.uber.org/zap/zaptest"
 )
@@ -103,7 +105,7 @@ func TestConsumer_Register(t *testing.T) {
 	c := consumer.New(logger, tally.NoopScope, reg, errs.NewClassifierProcessor())
 
 	handler1 := consumermock.NewMockController(ctrl)
-	setupController(handler1, "handler1", consumer.TopicKeyStart, "group1", nil)
+	setupController(handler1, "handler1", topickey.TopicKeyStart, "group1", nil)
 
 	handler2 := consumermock.NewMockController(ctrl)
 	setupController(handler2, "handler2", consumer.TopicKey("other-topic"), "group2", nil)
@@ -123,10 +125,10 @@ func TestConsumer_Register_DuplicateTopic(t *testing.T) {
 	c := consumer.New(logger, tally.NoopScope, reg, errs.NewClassifierProcessor())
 
 	handler1 := consumermock.NewMockController(ctrl)
-	setupController(handler1, "handler1", consumer.TopicKeyStart, "group1", nil)
+	setupController(handler1, "handler1", topickey.TopicKeyStart, "group1", nil)
 
 	handler2 := consumermock.NewMockController(ctrl)
-	setupController(handler2, "handler2", consumer.TopicKeyStart, "group2", nil)
+	setupController(handler2, "handler2", topickey.TopicKeyStart, "group2", nil)
 
 	err := c.Register(handler1)
 	require.NoError(t, err)
@@ -146,7 +148,7 @@ func TestConsumer_Register_AfterStop(t *testing.T) {
 	require.NoError(t, err)
 
 	handler := consumermock.NewMockController(ctrl)
-	setupController(handler, "handler1", consumer.TopicKeyStart, "group1", nil)
+	setupController(handler, "handler1", topickey.TopicKeyStart, "group1", nil)
 
 	err = c.Register(handler)
 	assert.Error(t, err)
@@ -170,7 +172,7 @@ func TestConsumer_Start_AfterStop(t *testing.T) {
 	c := consumer.New(logger, tally.NoopScope, reg, errs.NewClassifierProcessor())
 
 	handler := consumermock.NewMockController(ctrl)
-	setupController(handler, "handler1", consumer.TopicKeyStart, "group1", nil)
+	setupController(handler, "handler1", topickey.TopicKeyStart, "group1", nil)
 
 	err := c.Register(handler)
 	require.NoError(t, err)
@@ -189,14 +191,14 @@ func TestConsumer_Start_MissingSubscriptionConfig(t *testing.T) {
 	mockQ := queuemock.NewMockQueue(ctrl)
 	// Registry has queue but no subscription config
 	reg, err := consumer.NewTopicRegistry(
-		[]consumer.TopicConfig{{Key: consumer.TopicKeyStart, Name: "request", Queue: mockQ}},
+		[]consumer.TopicConfig{{Key: topickey.TopicKeyStart, Name: "request", Queue: mockQ}},
 	)
 	require.NoError(t, err)
 
 	c := consumer.New(logger, tally.NoopScope, reg, errs.NewClassifierProcessor())
 
 	handler := consumermock.NewMockController(ctrl)
-	setupController(handler, "handler", consumer.TopicKeyStart, "group", nil)
+	setupController(handler, "handler", topickey.TopicKeyStart, "group", nil)
 
 	err = c.Register(handler)
 	require.NoError(t, err)
@@ -217,12 +219,12 @@ func TestConsumer_Start_SubscribeFailure(t *testing.T) {
 	mockQ := queuemock.NewMockQueue(ctrl)
 	mockQ.EXPECT().Subscriber().Return(mockSub)
 
-	reg := newRegistry(t, mockQ, consumer.TopicKeyStart, "group")
+	reg := newRegistry(t, mockQ, topickey.TopicKeyStart, "group")
 
 	c := consumer.New(logger, tally.NoopScope, reg, errs.NewClassifierProcessor())
 
 	handler := consumermock.NewMockController(ctrl)
-	setupController(handler, "handler", consumer.TopicKeyStart, "group", nil)
+	setupController(handler, "handler", topickey.TopicKeyStart, "group", nil)
 
 	err := c.Register(handler)
 	require.NoError(t, err)
@@ -243,13 +245,13 @@ func TestConsumer_ProcessDelivery_Success(t *testing.T) {
 	mockQ := queuemock.NewMockQueue(ctrl)
 	mockQ.EXPECT().Subscriber().Return(mockSub)
 
-	reg := newRegistry(t, mockQ, consumer.TopicKeyStart, "test-group")
+	reg := newRegistry(t, mockQ, topickey.TopicKeyStart, "test-group")
 
 	c := consumer.New(logger, tally.NoopScope, reg, errs.NewClassifierProcessor())
 
 	handledMsg := ""
 	handler := consumermock.NewMockController(ctrl)
-	setupController(handler, "test-handler", consumer.TopicKeyStart, "test-group",
+	setupController(handler, "test-handler", topickey.TopicKeyStart, "test-group",
 		func(ctx context.Context, delivery consumer.Delivery) error {
 			handledMsg = delivery.Message().ID
 			return nil
@@ -289,12 +291,12 @@ func TestConsumer_ProcessDelivery_Error(t *testing.T) {
 	mockQ := queuemock.NewMockQueue(ctrl)
 	mockQ.EXPECT().Subscriber().Return(mockSub)
 
-	reg := newRegistry(t, mockQ, consumer.TopicKeyStart, "test-group")
+	reg := newRegistry(t, mockQ, topickey.TopicKeyStart, "test-group")
 
 	c := consumer.New(logger, tally.NoopScope, reg, errs.NewClassifierProcessor())
 
 	handler := consumermock.NewMockController(ctrl)
-	setupController(handler, "test-handler", consumer.TopicKeyStart, "test-group",
+	setupController(handler, "test-handler", topickey.TopicKeyStart, "test-group",
 		func(ctx context.Context, delivery consumer.Delivery) error {
 			return errs.NewRetryableError(fmt.Errorf("processing failed"))
 		},
@@ -331,12 +333,12 @@ func TestConsumer_ProcessDelivery_NonRetryableError(t *testing.T) {
 	mockQ := queuemock.NewMockQueue(ctrl)
 	mockQ.EXPECT().Subscriber().Return(mockSub)
 
-	reg := newRegistry(t, mockQ, consumer.TopicKeyStart, "test-group")
+	reg := newRegistry(t, mockQ, topickey.TopicKeyStart, "test-group")
 
 	c := consumer.New(logger, tally.NoopScope, reg, errs.NewClassifierProcessor())
 
 	handler := consumermock.NewMockController(ctrl)
-	setupController(handler, "test-handler", consumer.TopicKeyStart, "test-group",
+	setupController(handler, "test-handler", topickey.TopicKeyStart, "test-group",
 		func(ctx context.Context, delivery consumer.Delivery) error {
 			return fmt.Errorf("bad payload")
 		},
@@ -382,12 +384,12 @@ func TestConsumer_Stop(t *testing.T) {
 	mockQ := queuemock.NewMockQueue(ctrl)
 	mockQ.EXPECT().Subscriber().Return(mockSub)
 
-	reg := newRegistry(t, mockQ, consumer.TopicKeyStart, "test-group")
+	reg := newRegistry(t, mockQ, topickey.TopicKeyStart, "test-group")
 
 	c := consumer.New(logger, tally.NoopScope, reg, errs.NewClassifierProcessor())
 
 	handler := consumermock.NewMockController(ctrl)
-	setupController(handler, "test-handler", consumer.TopicKeyStart, "test-group", nil)
+	setupController(handler, "test-handler", topickey.TopicKeyStart, "test-group", nil)
 
 	err := c.Register(handler)
 	require.NoError(t, err)
@@ -440,12 +442,12 @@ func TestConsumer_ObservabilityTags(t *testing.T) {
 			mockQ := queuemock.NewMockQueue(ctrl)
 			mockQ.EXPECT().Subscriber().Return(mockSub)
 
-			reg := newRegistry(t, mockQ, consumer.TopicKeyStart, "test-group")
+			reg := newRegistry(t, mockQ, topickey.TopicKeyStart, "test-group")
 
 			testC := consumer.New(logger, testScope, reg, errs.NewClassifierProcessor())
 
 			handler := consumermock.NewMockController(ctrl)
-			setupController(handler, "test-handler", consumer.TopicKeyStart, "test-group",
+			setupController(handler, "test-handler", topickey.TopicKeyStart, "test-group",
 				func(ctx context.Context, delivery consumer.Delivery) error {
 					return tt.handlerError
 				},
@@ -515,12 +517,12 @@ func TestConsumer_AckNackLatencyTracking(t *testing.T) {
 	mockQ := queuemock.NewMockQueue(ctrl)
 	mockQ.EXPECT().Subscriber().Return(mockSub)
 
-	reg := newRegistry(t, mockQ, consumer.TopicKeyStart, "test-group")
+	reg := newRegistry(t, mockQ, topickey.TopicKeyStart, "test-group")
 
 	c := consumer.New(logger, scope, reg, errs.NewClassifierProcessor())
 
 	handler := consumermock.NewMockController(ctrl)
-	setupController(handler, "test-handler", consumer.TopicKeyStart, "test-group",
+	setupController(handler, "test-handler", topickey.TopicKeyStart, "test-group",
 		func(ctx context.Context, delivery consumer.Delivery) error { return nil },
 	)
 
@@ -560,12 +562,12 @@ func TestConsumer_ErrorMetrics(t *testing.T) {
 	mockQ := queuemock.NewMockQueue(ctrl)
 	mockQ.EXPECT().Subscriber().Return(mockSub)
 
-	reg := newRegistry(t, mockQ, consumer.TopicKeyStart, "test-group")
+	reg := newRegistry(t, mockQ, topickey.TopicKeyStart, "test-group")
 
 	c := consumer.New(logger, scope, reg, errs.NewClassifierProcessor())
 
 	handler := consumermock.NewMockController(ctrl)
-	setupController(handler, "test-handler", consumer.TopicKeyStart, "test-group",
+	setupController(handler, "test-handler", topickey.TopicKeyStart, "test-group",
 		func(ctx context.Context, delivery consumer.Delivery) error {
 			return errs.NewRetryableError(fmt.Errorf("processing failed"))
 		},
@@ -616,7 +618,7 @@ func TestConsumer_PerPartitionProcessing(t *testing.T) {
 	mockQ := queuemock.NewMockQueue(ctrl)
 	mockQ.EXPECT().Subscriber().Return(mockSub)
 
-	reg := newRegistry(t, mockQ, consumer.TopicKeyStart, "test-group")
+	reg := newRegistry(t, mockQ, topickey.TopicKeyStart, "test-group")
 
 	c := consumer.New(logger, tally.NoopScope, reg, errs.NewClassifierProcessor())
 
@@ -626,7 +628,7 @@ func TestConsumer_PerPartitionProcessing(t *testing.T) {
 	var partBProcessed atomic.Bool
 
 	handler := consumermock.NewMockController(ctrl)
-	setupController(handler, "test-handler", consumer.TopicKeyStart, "test-group",
+	setupController(handler, "test-handler", topickey.TopicKeyStart, "test-group",
 		func(ctx context.Context, delivery consumer.Delivery) error {
 			pk := delivery.Message().PartitionKey
 			if pk == "partition-a" {
@@ -701,7 +703,7 @@ func TestConsumer_PartitionOrdering(t *testing.T) {
 	mockQ := queuemock.NewMockQueue(ctrl)
 	mockQ.EXPECT().Subscriber().Return(mockSub)
 
-	reg := newRegistry(t, mockQ, consumer.TopicKeyStart, "test-group")
+	reg := newRegistry(t, mockQ, topickey.TopicKeyStart, "test-group")
 
 	c := consumer.New(logger, tally.NoopScope, reg, errs.NewClassifierProcessor())
 
@@ -712,7 +714,7 @@ func TestConsumer_PartitionOrdering(t *testing.T) {
 	allDone := make(chan struct{})
 
 	handler := consumermock.NewMockController(ctrl)
-	setupController(handler, "test-handler", consumer.TopicKeyStart, "test-group",
+	setupController(handler, "test-handler", topickey.TopicKeyStart, "test-group",
 		func(ctx context.Context, delivery consumer.Delivery) error {
 			mu.Lock()
 			order = append(order, delivery.Message().ID)
@@ -770,14 +772,14 @@ func TestConsumer_PartitionWorkerCleanup(t *testing.T) {
 	mockQ := queuemock.NewMockQueue(ctrl)
 	mockQ.EXPECT().Subscriber().Return(mockSub)
 
-	reg := newRegistry(t, mockQ, consumer.TopicKeyStart, "test-group")
+	reg := newRegistry(t, mockQ, topickey.TopicKeyStart, "test-group")
 
 	c := consumer.New(logger, tally.NoopScope, reg, errs.NewClassifierProcessor())
 
 	processedCount := int64(0)
 
 	handler := consumermock.NewMockController(ctrl)
-	setupController(handler, "test-handler", consumer.TopicKeyStart, "test-group",
+	setupController(handler, "test-handler", topickey.TopicKeyStart, "test-group",
 		func(ctx context.Context, delivery consumer.Delivery) error {
 			atomic.AddInt64(&processedCount, 1)
 			return nil

…bmitqueue/core/consumer/consumer_test.go core/consumer/consumer_test.gosubmitqueue/core/consumer/consumer_test.go renamed to core/consumer/consumer_test.go submitqueue/core/consumer/consumer_test.go renamed to core/consumer/consumer_test.go

@@ -3,11 +3,11 @@ load("@rules_go//go:def.bzl", "go_library")
 go_library(
     name = "mock",
     srcs = ["controller_mock.go"],
-    importpath = "github.com/uber/submitqueue/submitqueue/core/consumer/mock",
+    importpath = "github.com/uber/submitqueue/core/consumer/mock",
     visibility = ["//visibility:public"],
     deps = [
+        "//core/consumer",
         "//entity/messagequeue",
-        "//submitqueue/core/consumer",
         "@org_uber_go_mock//gomock",
     ],
 )