Merge branch 'pks-create-fork-preparatory-refactorings' into 'master'

Preparatory refactorings for linking to pool repos in CreateFork

See merge request https://gitlab.com/gitlab-org/gitaly/-/merge_requests/5718

Merged-by: Pavlo Strokov <pstrokov@gitlab.com>
Approved-by: Pavlo Strokov <pstrokov@gitlab.com>
Reviewed-by: Patrick Steinhardt <psteinhardt@gitlab.com>
Reviewed-by: Pavlo Strokov <pstrokov@gitlab.com>
Co-authored-by: Patrick Steinhardt <psteinhardt@gitlab.com>

19 files changed, 186 insertions, 171 deletions

diff --git a/internal/git/gittest/objectpool.go b/internal/git/gittest/objectpool.go
new file mode 100644
index 000000000..3374b736b
--- /dev/null
+++ b/internal/git/gittest/objectpool.go
@@ -0,0 +1,91 @@
+package gittest
+
+import (
+	"context"
+	"path/filepath"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+	"gitlab.com/gitlab-org/gitaly/v15/internal/gitaly/config"
+	"gitlab.com/gitlab-org/gitaly/v15/internal/testhelper"
+	"gitlab.com/gitlab-org/gitaly/v15/proto/go/gitalypb"
+	"google.golang.org/grpc"
+)
+
+// CreateObjectPoolConfig can be used to tweak how CreateObjectPool behaves.
+type CreateObjectPoolConfig struct {
+	// ClientConn is the connection used to create the repository. If unset, the config is used
+	// to dial the service.
+	ClientConn *grpc.ClientConn
+	// RelativePath sets the relative path of the repository in the storage. If unset,
+	// the relative path is set to a randomly generated hashed storage path.
+	RelativePath string
+	// LinkRepositoryToObjectPool determines whether the repository shall be linked to the object
+	// pool.
+	LinkRepositoryToObjectPool bool
+}
+
+// CreateObjectPool creates a new object pool from the given source repository. It returns the
+// Protobuf representation used for gRPC calls. This can be passed either no or exactly one
+// CreateObjectPoolConfig to influence how the pool will be created.
+func CreateObjectPool(
+	tb testing.TB,
+	ctx context.Context,
+	cfg config.Cfg,
+	source *gitalypb.Repository,
+	optionalCfg ...CreateObjectPoolConfig,
+) (*gitalypb.ObjectPool, string) {
+	tb.Helper()
+
+	require.LessOrEqual(tb, len(optionalCfg), 1)
+	var createCfg CreateObjectPoolConfig
+	if len(optionalCfg) == 1 {
+		createCfg = optionalCfg[0]
+	}
+
+	conn := createCfg.ClientConn
+	if conn == nil {
+		conn = dialService(tb, ctx, cfg)
+		defer testhelper.MustClose(tb, conn)
+	}
+	client := gitalypb.NewObjectPoolServiceClient(conn)
+
+	// We use the same storage as the source repository. So we need to figure out whether we
+	// actually have the storage configuration for it.
+	var storage config.Storage
+	for _, s := range cfg.Storages {
+		if s.Name == source.StorageName {
+			storage = s
+			break
+		}
+	}
+	require.NotEmpty(tb, storage.Name)
+
+	relativePath := createCfg.RelativePath
+	if relativePath == "" {
+		relativePath = NewObjectPoolName(tb)
+	}
+
+	poolProto := &gitalypb.ObjectPool{
+		Repository: &gitalypb.Repository{
+			StorageName:  storage.Name,
+			RelativePath: relativePath,
+		},
+	}
+
+	_, err := client.CreateObjectPool(ctx, &gitalypb.CreateObjectPoolRequest{
+		ObjectPool: poolProto,
+		Origin:     source,
+	})
+	require.NoError(tb, err)
+
+	if createCfg.LinkRepositoryToObjectPool {
+		_, err := client.LinkRepositoryToObjectPool(ctx, &gitalypb.LinkRepositoryToObjectPoolRequest{
+			ObjectPool: poolProto,
+			Repository: source,
+		})
+		require.NoError(tb, err)
+	}
+
+	return poolProto, filepath.Join(storage.Path, getReplicaPath(tb, ctx, conn, poolProto.Repository))
+}
diff --git a/internal/gitaly/service/objectpool/alternates_test.go b/internal/gitaly/service/objectpool/alternates_test.go
index 02355b70c..e6e58f091 100644
--- a/internal/gitaly/service/objectpool/alternates_test.go
+++ b/internal/gitaly/service/objectpool/alternates_test.go
@@ -38,7 +38,7 @@ func testDisconnectGitAlternates(t *testing.T, ctx context.Context) {
 	// We create the object pool, link the original repository to it and then repack the pool
 	// member. As the linking step should've pulled all objects into the pool, the repack should
 	// get rid of the now-duplicate objects in the repository in favor of the pooled ones.
-	_, pool, _ := createObjectPool(t, ctx, cfg, client, repoProto)
+	_, pool, _ := createObjectPool(t, ctx, cfg, repoProto)
 	require.NoError(t, pool.Link(ctx, repo))
 	gittest.Exec(t, cfg, "-C", repoPath, "gc")
 
diff --git a/internal/gitaly/service/objectpool/delete_test.go b/internal/gitaly/service/objectpool/delete_test.go
index 77b613b25..ed95f2d8c 100644
--- a/internal/gitaly/service/objectpool/delete_test.go
+++ b/internal/gitaly/service/objectpool/delete_test.go
@@ -21,7 +21,7 @@ func TestDelete(t *testing.T) {
 
 	repositoryClient := gitalypb.NewRepositoryServiceClient(extractConn(client))
 
-	poolProto, _, _ := createObjectPool(t, ctx, cfg, client, repoProto)
+	poolProto, _, _ := createObjectPool(t, ctx, cfg, repoProto)
 	validPoolPath := poolProto.GetRepository().GetRelativePath()
 
 	for _, tc := range []struct {
diff --git a/internal/gitaly/service/objectpool/fetch_into_object_pool_test.go b/internal/gitaly/service/objectpool/fetch_into_object_pool_test.go
index 93c4a9c74..227f113fa 100644
--- a/internal/gitaly/service/objectpool/fetch_into_object_pool_test.go
+++ b/internal/gitaly/service/objectpool/fetch_into_object_pool_test.go
@@ -47,7 +47,7 @@ func testFetchIntoObjectPoolSuccess(t *testing.T, ctx context.Context) {
 
 	parentID := gittest.WriteCommit(t, cfg, repoPath, gittest.WithBranch("main"))
 
-	poolProto, _, poolPath := createObjectPool(t, ctx, cfg, client, repo)
+	poolProto, _, poolPath := createObjectPool(t, ctx, cfg, repo)
 
 	// Create a new commit after having created the object pool. This commit exists only in the
 	// pool member, but not in the pool itself.
@@ -126,7 +126,7 @@ func testFetchIntoObjectPoolTransactional(t *testing.T, ctx context.Context) {
 
 	client := gitalypb.NewObjectPoolServiceClient(conn)
 
-	poolProto, pool, poolPath := createObjectPool(t, ctx, cfg, client, repo)
+	poolProto, pool, poolPath := createObjectPool(t, ctx, cfg, repo)
 
 	// Inject transaction information so that FetchInotObjectPool knows to perform
 	// transactional voting.
@@ -230,7 +230,7 @@ func testFetchIntoObjectPoolcollectLogStatistics(t *testing.T, ctx context.Conte
 	t.Cleanup(func() { testhelper.MustClose(t, conn) })
 	client := gitalypb.NewObjectPoolServiceClient(conn)
 
-	poolProto, _, _ := createObjectPool(t, ctx, cfg, client, repo)
+	poolProto, _, _ := createObjectPool(t, ctx, cfg, repo)
 
 	req := &gitalypb.FetchIntoObjectPoolRequest{
 		ObjectPool: poolProto,
@@ -254,7 +254,7 @@ func TestFetchIntoObjectPool_Failure(t *testing.T) {
 
 	ctx := testhelper.Context(t)
 	cfg, repo, _, _, client := setup(t, ctx, testserver.WithDisablePraefect())
-	poolProto, _, _ := createObjectPool(t, ctx, cfg, client, repo)
+	poolProto, _, _ := createObjectPool(t, ctx, cfg, repo)
 
 	poolWithDifferentStorage := proto.Clone(poolProto).(*gitalypb.ObjectPool)
 	poolWithDifferentStorage.Repository.StorageName = "some other storage"
@@ -309,7 +309,7 @@ func testFetchIntoObjectPoolDfConflict(t *testing.T, ctx context.Context) {
 	t.Parallel()
 
 	cfg, repo, repoPath, _, client := setup(t, ctx)
-	poolProto, _, poolPath := createObjectPool(t, ctx, cfg, client, repo)
+	poolProto, _, poolPath := createObjectPool(t, ctx, cfg, repo)
 
 	gittest.WriteCommit(t, cfg, repoPath, gittest.WithBranch("branch"))
 
diff --git a/internal/gitaly/service/objectpool/get_test.go b/internal/gitaly/service/objectpool/get_test.go
index 86453e711..60afec0e2 100644
--- a/internal/gitaly/service/objectpool/get_test.go
+++ b/internal/gitaly/service/objectpool/get_test.go
@@ -21,7 +21,7 @@ func TestGetObjectPoolSuccess(t *testing.T) {
 	cfg, repoProto, _, _, client := setup(t, ctx)
 	repo := localrepo.NewTestRepo(t, cfg, repoProto)
 
-	_, pool, _ := createObjectPool(t, ctx, cfg, client, repoProto)
+	_, pool, _ := createObjectPool(t, ctx, cfg, repoProto)
 	relativePoolPath := pool.GetRelativePath()
 	require.NoError(t, pool.Link(ctx, repo))
 
diff --git a/internal/gitaly/service/objectpool/link_test.go b/internal/gitaly/service/objectpool/link_test.go
index 6c4109a69..2a49015e2 100644
--- a/internal/gitaly/service/objectpool/link_test.go
+++ b/internal/gitaly/service/objectpool/link_test.go
@@ -23,7 +23,7 @@ func TestLink(t *testing.T) {
 	cfg, repo, _, _, client := setup(t, ctx, testserver.WithDisablePraefect())
 
 	localRepo := localrepo.NewTestRepo(t, cfg, repo)
-	poolProto, _, poolPath := createObjectPool(t, ctx, cfg, client, repo)
+	poolProto, _, poolPath := createObjectPool(t, ctx, cfg, repo)
 
 	// Mock object in the pool, which should be available to the pool members
 	// after linking
@@ -80,7 +80,7 @@ func TestLink_idempotent(t *testing.T) {
 	ctx := testhelper.Context(t)
 	cfg, repoProto, _, _, client := setup(t, ctx)
 
-	poolProto, _, _ := createObjectPool(t, ctx, cfg, client, repoProto)
+	poolProto, _, _ := createObjectPool(t, ctx, cfg, repoProto)
 
 	request := &gitalypb.LinkRepositoryToObjectPoolRequest{
 		Repository: repoProto,
@@ -99,7 +99,7 @@ func TestLink_noClobber(t *testing.T) {
 
 	ctx := testhelper.Context(t)
 	cfg, repoProto, repoPath, _, client := setup(t, ctx)
-	poolProto, _, _ := createObjectPool(t, ctx, cfg, client, repoProto)
+	poolProto, _, _ := createObjectPool(t, ctx, cfg, repoProto)
 
 	alternatesFile := filepath.Join(repoPath, "objects/info/alternates")
 	require.NoFileExists(t, alternatesFile)
diff --git a/internal/gitaly/service/objectpool/testhelper_test.go b/internal/gitaly/service/objectpool/testhelper_test.go
index 8665a01cd..dd78f09b8 100644
--- a/internal/gitaly/service/objectpool/testhelper_test.go
+++ b/internal/gitaly/service/objectpool/testhelper_test.go
@@ -93,23 +93,11 @@ func createObjectPool(
 	tb testing.TB,
 	ctx context.Context,
 	cfg config.Cfg,
-	client gitalypb.ObjectPoolServiceClient,
 	source *gitalypb.Repository,
 ) (*gitalypb.ObjectPool, *objectpool.ObjectPool, string) {
 	tb.Helper()
 
-	poolProto := &gitalypb.ObjectPool{
-		Repository: &gitalypb.Repository{
-			StorageName:  source.GetStorageName(),
-			RelativePath: gittest.NewObjectPoolName(tb),
-		},
-	}
-
-	_, err := client.CreateObjectPool(ctx, &gitalypb.CreateObjectPoolRequest{
-		ObjectPool: poolProto,
-		Origin:     source,
-	})
-	require.NoError(tb, err)
+	poolProto, poolProtoPath := gittest.CreateObjectPool(tb, ctx, cfg, source)
 
 	txManager := transaction.NewManager(cfg, nil)
 	catfileCache := catfile.NewCache(cfg)
@@ -130,5 +118,5 @@ func createObjectPool(
 	)
 	require.NoError(tb, err)
 
-	return poolProto, pool, gittest.RepositoryPath(tb, pool)
+	return poolProto, pool, poolProtoPath
 }
diff --git a/internal/gitaly/service/repository/create_fork.go b/internal/gitaly/service/repository/create_fork.go
index bb172eac5..d10307639 100644
--- a/internal/gitaly/service/repository/create_fork.go
+++ b/internal/gitaly/service/repository/create_fork.go
@@ -13,16 +13,16 @@ import (
 )
 
 func (s *server) CreateFork(ctx context.Context, req *gitalypb.CreateForkRequest) (*gitalypb.CreateForkResponse, error) {
-	targetRepository := req.Repository
-	sourceRepository := req.SourceRepository
-
-	if sourceRepository == nil {
-		return nil, structerr.NewInvalidArgument("empty SourceRepository")
+	if err := service.ValidateRepository(req.GetSourceRepository()); err != nil {
+		return nil, structerr.NewInvalidArgument("validating source repository: %w", err)
 	}
 	if err := service.ValidateRepository(req.GetRepository()); err != nil {
 		return nil, structerr.NewInvalidArgument("%w", err)
 	}
 
+	targetRepository := req.Repository
+	sourceRepository := req.SourceRepository
+
 	if err := repoutil.Create(ctx, s.locator, s.gitCmdFactory, s.txManager, targetRepository, func(repo *gitalypb.Repository) error {
 		targetPath, err := s.locator.GetPath(repo)
 		if err != nil {
diff --git a/internal/gitaly/service/repository/create_fork_test.go b/internal/gitaly/service/repository/create_fork_test.go
index ff68a9051..a1352e1eb 100644
--- a/internal/gitaly/service/repository/create_fork_test.go
+++ b/internal/gitaly/service/repository/create_fork_test.go
@@ -283,7 +283,7 @@ func TestCreateFork_validate(t *testing.T) {
 				if testhelper.IsPraefectEnabled() {
 					return status.Error(codes.AlreadyExists, "route repository creation: reserve repository id: repository already exists")
 				}
-				return status.Error(codes.InvalidArgument, "empty SourceRepository")
+				return status.Error(codes.InvalidArgument, "validating source repository: empty Repository")
 			}(),
 		},
 	} {
diff --git a/internal/gitaly/service/repository/size_test.go b/internal/gitaly/service/repository/size_test.go
index 1143a6b9e..b0e740e8b 100644
--- a/internal/gitaly/service/repository/size_test.go
+++ b/internal/gitaly/service/repository/size_test.go
@@ -9,7 +9,6 @@ import (
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/git"
-	"gitlab.com/gitlab-org/gitaly/v15/internal/git/catfile"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/git/gittest"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/git/quarantine"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/gitaly/config"
@@ -33,8 +32,6 @@ func TestSuccessfulRepositorySizeRequestPoolMember(t *testing.T) {
 	repoClient, serverSocketPath := runRepositoryService(t, cfg)
 	cfg.SocketPath = serverSocketPath
 
-	objectPoolClient := newObjectPoolClient(t, cfg, serverSocketPath)
-
 	repo, repoPath := gittest.CreateRepository(t, ctx, cfg, gittest.CreateRepositoryConfig{
 		Seed: gittest.SeedGitLabTest,
 	})
@@ -45,32 +42,9 @@ func TestSuccessfulRepositorySizeRequestPoolMember(t *testing.T) {
 
 	sizeBeforePool := response.GetSize()
 
-	catfileCache := catfile.NewCache(cfg)
-	t.Cleanup(catfileCache.Stop)
-
-	poolProto := &gitalypb.ObjectPool{
-		Repository: &gitalypb.Repository{
-			StorageName:  cfg.Storages[0].Name,
-			RelativePath: gittest.NewObjectPoolName(t),
-		},
-	}
-
-	_, err = objectPoolClient.CreateObjectPool(
-		ctx,
-		&gitalypb.CreateObjectPoolRequest{
-			ObjectPool: poolProto,
-			Origin:     repo,
-		})
-	require.NoError(t, err)
-
-	_, err = objectPoolClient.LinkRepositoryToObjectPool(
-		ctx,
-		&gitalypb.LinkRepositoryToObjectPoolRequest{
-			Repository: repo,
-			ObjectPool: poolProto,
-		},
-	)
-	require.NoError(t, err)
+	gittest.CreateObjectPool(t, ctx, cfg, repo, gittest.CreateObjectPoolConfig{
+		LinkRepositoryToObjectPool: true,
+	})
 
 	gittest.Exec(t, cfg, "-C", repoPath, "gc")
 
diff --git a/internal/gitaly/service/repository/testhelper_test.go b/internal/gitaly/service/repository/testhelper_test.go
index 1d82a3710..0bf885d69 100644
--- a/internal/gitaly/service/repository/testhelper_test.go
+++ b/internal/gitaly/service/repository/testhelper_test.go
@@ -44,14 +44,6 @@ func newRepositoryClient(tb testing.TB, cfg config.Cfg, serverSocketPath string)
 	return gitalypb.NewRepositoryServiceClient(conn)
 }
 
-func newObjectPoolClient(tb testing.TB, cfg config.Cfg, serverSocketPath string) gitalypb.ObjectPoolServiceClient {
-	conn, err := gclient.Dial(serverSocketPath, nil)
-	require.NoError(tb, err)
-	tb.Cleanup(func() { require.NoError(tb, conn.Close()) })
-
-	return gitalypb.NewObjectPoolServiceClient(conn)
-}
-
 func newMuxedRepositoryClient(t *testing.T, ctx context.Context, cfg config.Cfg, serverSocketPath string, handshaker internalclient.Handshaker) gitalypb.RepositoryServiceClient {
 	conn, err := internalclient.Dial(ctx, serverSocketPath, []grpc.DialOption{
 		grpc.WithPerRPCCredentials(gitalyauth.RPCCredentialsV2(cfg.Auth.Token)),
diff --git a/internal/gitaly/service/smarthttp/inforefs_test.go b/internal/gitaly/service/smarthttp/inforefs_test.go
index 2c08a5e88..a699f5f5c 100644
--- a/internal/gitaly/service/smarthttp/inforefs_test.go
+++ b/internal/gitaly/service/smarthttp/inforefs_test.go
@@ -12,16 +12,11 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/require"
-	"gitlab.com/gitlab-org/gitaly/v15/internal/backchannel"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/cache"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/git"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/git/gittest"
-	"gitlab.com/gitlab-org/gitaly/v15/internal/git/housekeeping"
-	"gitlab.com/gitlab-org/gitaly/v15/internal/git/localrepo"
-	"gitlab.com/gitlab-org/gitaly/v15/internal/git/objectpool"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/git/stats"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/gitaly/config"
-	"gitlab.com/gitlab-org/gitaly/v15/internal/gitaly/transaction"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/helper/perm"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/metadata/featureflag"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/testhelper"
@@ -302,36 +297,16 @@ func TestInfoRefsReceivePack_hiddenRefs(t *testing.T) {
 	ctx := testhelper.Context(t)
 
 	repoProto, repoPath := gittest.CreateRepository(t, ctx, cfg)
-	repo := localrepo.NewTestRepo(t, cfg, repoProto)
 	gittest.WriteCommit(t, cfg, repoPath, gittest.WithBranch("main"))
 
-	txManager := transaction.NewManager(cfg, backchannel.NewRegistry())
-
-	pool, err := objectpool.Create(
-		ctx,
-		config.NewLocator(cfg),
-		gittest.NewCommandFactory(t, cfg),
-		nil,
-		txManager,
-		housekeeping.NewManager(cfg.Prometheus, txManager),
-		&gitalypb.ObjectPool{
-			Repository: &gitalypb.Repository{
-				StorageName:  repo.GetStorageName(),
-				RelativePath: gittest.NewObjectPoolName(t),
-			},
-		},
-		repo,
-	)
-	require.NoError(t, err)
-	poolPath := gittest.RepositoryPath(t, pool)
-
+	_, poolPath := gittest.CreateObjectPool(t, ctx, cfg, repoProto, gittest.CreateObjectPoolConfig{
+		LinkRepositoryToObjectPool: true,
+	})
 	commitID := gittest.WriteCommit(t, cfg, poolPath, gittest.WithBranch(t.Name()))
 
-	require.NoError(t, pool.Link(ctx, repo))
-
-	rpcRequest := &gitalypb.InfoRefsRequest{Repository: repoProto}
-
-	response, err := makeInfoRefsReceivePackRequest(t, ctx, cfg.SocketPath, cfg.Auth.Token, rpcRequest)
+	response, err := makeInfoRefsReceivePackRequest(t, ctx, cfg.SocketPath, cfg.Auth.Token, &gitalypb.InfoRefsRequest{
+		Repository: repoProto,
+	})
 	require.NoError(t, err)
 	require.NotContains(t, string(response), commitID+" .have")
 }
diff --git a/internal/gitaly/service/smarthttp/testhelper_test.go b/internal/gitaly/service/smarthttp/testhelper_test.go
index 55d4429b5..57e206e09 100644
--- a/internal/gitaly/service/smarthttp/testhelper_test.go
+++ b/internal/gitaly/service/smarthttp/testhelper_test.go
@@ -11,6 +11,7 @@ import (
 	"gitlab.com/gitlab-org/gitaly/v15/internal/gitaly/config"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/gitaly/service"
 	hookservice "gitlab.com/gitlab-org/gitaly/v15/internal/gitaly/service/hook"
+	"gitlab.com/gitlab-org/gitaly/v15/internal/gitaly/service/objectpool"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/gitaly/service/repository"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/testhelper"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/testhelper/testserver"
@@ -46,6 +47,13 @@ func startSmartHTTPServerWithOptions(t *testing.T, cfg config.Cfg, opts []Server
 			deps.GetGit2goExecutor(),
 			deps.GetHousekeepingManager(),
 		))
+		gitalypb.RegisterObjectPoolServiceServer(srv, objectpool.NewServer(
+			deps.GetLocator(),
+			deps.GetGitCmdFactory(),
+			deps.GetCatfileCache(),
+			deps.GetTxManager(),
+			deps.GetHousekeepingManager(),
+		))
 		gitalypb.RegisterHookServiceServer(srv, hookservice.NewServer(deps.GetHookManager(), deps.GetGitCmdFactory(), deps.GetPackObjectsCache(), deps.GetPackObjectsConcurrencyTracker(), deps.GetPackObjectsLimiter()))
 	}, serverOpts...)
 }
diff --git a/internal/gitaly/service/ssh/receive_pack_test.go b/internal/gitaly/service/ssh/receive_pack_test.go
index 56b836e4a..8966fa76f 100644
--- a/internal/gitaly/service/ssh/receive_pack_test.go
+++ b/internal/gitaly/service/ssh/receive_pack_test.go
@@ -12,12 +12,9 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/require"
-	"gitlab.com/gitlab-org/gitaly/v15/internal/backchannel"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/git"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/git/gittest"
-	"gitlab.com/gitlab-org/gitaly/v15/internal/git/housekeeping"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/git/localrepo"
-	"gitlab.com/gitlab-org/gitaly/v15/internal/git/objectpool"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/gitaly/config"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/gitaly/transaction"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/gitlab"
@@ -421,33 +418,15 @@ func TestReceivePack_hidesObjectPoolReferences(t *testing.T) {
 	testcfg.BuildGitalyHooks(t, cfg)
 
 	repoProto, _ := gittest.CreateRepository(t, ctx, cfg)
-	repo := localrepo.NewTestRepo(t, cfg, repoProto)
-	txManager := transaction.NewManager(cfg, backchannel.NewRegistry())
 
 	client := newSSHClient(t, cfg.SocketPath)
 
 	stream, err := client.SSHReceivePack(ctx)
 	require.NoError(t, err)
 
-	pool, err := objectpool.Create(
-		ctx,
-		config.NewLocator(cfg),
-		gittest.NewCommandFactory(t, cfg),
-		nil,
-		txManager,
-		housekeeping.NewManager(cfg.Prometheus, txManager),
-		&gitalypb.ObjectPool{
-			Repository: &gitalypb.Repository{
-				StorageName:  repo.GetStorageName(),
-				RelativePath: gittest.NewObjectPoolName(t),
-			},
-		},
-		repo,
-	)
-	require.NoError(t, err)
-	require.NoError(t, pool.Link(ctx, repo))
-	poolPath := gittest.RepositoryPath(t, pool)
-
+	_, poolPath := gittest.CreateObjectPool(t, ctx, cfg, repoProto, gittest.CreateObjectPoolConfig{
+		LinkRepositoryToObjectPool: true,
+	})
 	commitID := gittest.WriteCommit(t, cfg, poolPath, gittest.WithBranch(t.Name()))
 
 	// First request
diff --git a/internal/gitaly/service/ssh/testhelper_test.go b/internal/gitaly/service/ssh/testhelper_test.go
index 4c910edc3..dded96cba 100644
--- a/internal/gitaly/service/ssh/testhelper_test.go
+++ b/internal/gitaly/service/ssh/testhelper_test.go
@@ -7,6 +7,7 @@ import (
 	"gitlab.com/gitlab-org/gitaly/v15/internal/gitaly/config"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/gitaly/service"
 	hookservice "gitlab.com/gitlab-org/gitaly/v15/internal/gitaly/service/hook"
+	"gitlab.com/gitlab-org/gitaly/v15/internal/gitaly/service/objectpool"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/gitaly/service/repository"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/testhelper"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/testhelper/testserver"
@@ -51,6 +52,13 @@ func startSSHServerWithOptions(t *testing.T, cfg config.Cfg, opts []ServerOpt, s
 			deps.GetGit2goExecutor(),
 			deps.GetHousekeepingManager(),
 		))
+		gitalypb.RegisterObjectPoolServiceServer(srv, objectpool.NewServer(
+			deps.GetLocator(),
+			deps.GetGitCmdFactory(),
+			deps.GetCatfileCache(),
+			deps.GetTxManager(),
+			deps.GetHousekeepingManager(),
+		))
 	}, serverOpts...)
 }
 
diff --git a/internal/praefect/replicator_test.go b/internal/praefect/replicator_test.go
index 2659eb0a6..80d891037 100644
--- a/internal/praefect/replicator_test.go
+++ b/internal/praefect/replicator_test.go
@@ -17,15 +17,9 @@ import (
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	gitalyauth "gitlab.com/gitlab-org/gitaly/v15/auth"
-	"gitlab.com/gitlab-org/gitaly/v15/internal/backchannel"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/git/gittest"
-	"gitlab.com/gitlab-org/gitaly/v15/internal/git/housekeeping"
-	"gitlab.com/gitlab-org/gitaly/v15/internal/git/localrepo"
-	"gitlab.com/gitlab-org/gitaly/v15/internal/git/objectpool"
-	gconfig "gitlab.com/gitlab-org/gitaly/v15/internal/gitaly/config"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/gitaly/service/setup"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/gitaly/storage"
-	"gitlab.com/gitlab-org/gitaly/v15/internal/gitaly/transaction"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/helper"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/middleware/metadatahandler"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/praefect/config"
@@ -57,7 +51,6 @@ func TestReplMgr_ProcessBacklog(t *testing.T) {
 		Seed:                   gittest.SeedGitLabTest,
 	})
 
-	testRepo := localrepo.NewTestRepo(t, primaryCfg, testRepoProto)
 	primaryCfg.SocketPath = testserver.RunGitalyServer(t, primaryCfg, setup.RegisterAll, testserver.WithDisablePraefect())
 	testcfg.BuildGitalySSH(t, primaryCfg)
 	testcfg.BuildGitalyHooks(t, primaryCfg)
@@ -83,41 +76,22 @@ func TestReplMgr_ProcessBacklog(t *testing.T) {
 		}},
 	}
 
-	txManager := transaction.NewManager(primaryCfg, backchannel.NewRegistry())
-
 	// create object pool on the source
-	poolCtx := testhelper.Context(t)
-	objectPoolPath := gittest.NewObjectPoolName(t)
-	pool, err := objectpool.Create(
-		poolCtx,
-		gconfig.NewLocator(primaryCfg),
-		gittest.NewCommandFactory(t, primaryCfg),
-		nil,
-		txManager,
-		housekeeping.NewManager(primaryCfg.Prometheus, txManager),
-		&gitalypb.ObjectPool{
-			Repository: &gitalypb.Repository{
-				StorageName:  testRepoProto.GetStorageName(),
-				RelativePath: objectPoolPath,
-			},
-		},
-		testRepo,
-	)
-	require.NoError(t, err)
-	require.NoError(t, pool.Link(poolCtx, testRepo))
+	poolRepository, _ := gittest.CreateObjectPool(t, ctx, primaryCfg, testRepoProto, gittest.CreateObjectPoolConfig{
+		LinkRepositoryToObjectPool: true,
+	})
 
 	// replicate object pool repository to target node
-	poolRepository := pool.ToProto().GetRepository()
-	targetObjectPoolRepo := proto.Clone(poolRepository).(*gitalypb.Repository)
-	targetObjectPoolRepo.StorageName = backupCfg.Storages[0].Name
+	targetObjectPoolRepo := proto.Clone(poolRepository).(*gitalypb.ObjectPool)
+	targetObjectPoolRepo.Repository.StorageName = backupCfg.Storages[0].Name
 	ctx, cancel := context.WithCancel(ctx)
 
 	injectedCtx := metadata.NewOutgoingContext(ctx, testcfg.GitalyServersMetadataFromCfg(t, primaryCfg))
 
 	repoClient := newRepositoryClient(t, backupCfg.SocketPath, backupCfg.Auth.Token)
-	_, err = repoClient.ReplicateRepository(injectedCtx, &gitalypb.ReplicateRepositoryRequest{
-		Repository: targetObjectPoolRepo,
-		Source:     poolRepository,
+	_, err := repoClient.ReplicateRepository(injectedCtx, &gitalypb.ReplicateRepositoryRequest{
+		Repository: targetObjectPoolRepo.Repository,
+		Source:     poolRepository.Repository,
 	})
 	require.NoError(t, err)
 
@@ -142,7 +116,7 @@ func TestReplMgr_ProcessBacklog(t *testing.T) {
 				Change:            datastore.UpdateRepo,
 				TargetNodeStorage: secondary.GetStorage(),
 				SourceNodeStorage: shard.Primary.GetStorage(),
-				RelativePath:      testRepo.GetRelativePath(),
+				RelativePath:      testRepoProto.GetRelativePath(),
 			},
 			State:   datastore.JobStateReady,
 			Attempt: 3,
@@ -171,7 +145,7 @@ func TestReplMgr_ProcessBacklog(t *testing.T) {
 
 	db := testdb.New(t)
 	rs := datastore.NewPostgresRepositoryStore(db, conf.StorageNames())
-	require.NoError(t, rs.CreateRepository(ctx, repositoryID, conf.VirtualStorages[0].Name, testRepo.GetRelativePath(), testRepo.GetRelativePath(), shard.Primary.GetStorage(), nil, nil, true, false))
+	require.NoError(t, rs.CreateRepository(ctx, repositoryID, conf.VirtualStorages[0].Name, testRepoProto.GetRelativePath(), testRepoProto.GetRelativePath(), shard.Primary.GetStorage(), nil, nil, true, false))
 
 	replMgr := NewReplMgr(
 		loggerEntry,
@@ -213,7 +187,7 @@ func TestReplMgr_ProcessBacklog(t *testing.T) {
 		[]interface{}{logEntries[3].Message, logEntries[3].Data["virtual_storage"], logEntries[3].Data["new_state"], logEntries[3].Data[logWithCorrID]},
 	)
 
-	replicatedPath := filepath.Join(backupCfg.Storages[0].Path, testRepo.GetRelativePath())
+	replicatedPath := filepath.Join(backupCfg.Storages[0].Path, testRepoProto.GetRelativePath())
 
 	gittest.Exec(t, backupCfg, "-C", replicatedPath, "cat-file", "-e", commitID.String())
 	gittest.Exec(t, backupCfg, "-C", replicatedPath, "gc")
diff --git a/proto/go/gitalypb/repository.pb.go b/proto/go/gitalypb/repository.pb.go
index d12d5ee06..144c52b9d 100644
--- a/proto/go/gitalypb/repository.pb.go
+++ b/proto/go/gitalypb/repository.pb.go
@@ -1829,15 +1829,19 @@ func (x *FindMergeBaseResponse) GetBase() string {
 	return ""
 }
 
-// This comment is left unintentionally blank.
+// CreateForkRequest is a request for the CreateFork RPC.
 type CreateForkRequest struct {
 	state         protoimpl.MessageState
 	sizeCache     protoimpl.SizeCache
 	unknownFields protoimpl.UnknownFields
 
-	// This comment is left unintentionally blank.
+	// Repository is the repository that shall be created.
 	Repository *Repository `protobuf:"bytes,1,opt,name=repository,proto3" json:"repository,omitempty"`
-	// This comment is left unintentionally blank.
+	// SourceRepository is the repository that shall be forked.
+	//
+	// Note that the source repository is intentionally not marked as an additional repository that is
+	// to be rewritten by Praefect. This is because Gitaly will use the source repository to perform a
+	// gRPC call, which must use the original non-rewritten repository.
 	SourceRepository *Repository `protobuf:"bytes,2,opt,name=source_repository,json=sourceRepository,proto3" json:"source_repository,omitempty"`
 }
 
@@ -1887,7 +1891,7 @@ func (x *CreateForkRequest) GetSourceRepository() *Repository {
 	return nil
 }
 
-// This comment is left unintentionally blank.
+// CreateForkResponse is a response for the CreateFork RPC.
 type CreateForkResponse struct {
 	state         protoimpl.MessageState
 	sizeCache     protoimpl.SizeCache
diff --git a/proto/go/gitalypb/repository_grpc.pb.go b/proto/go/gitalypb/repository_grpc.pb.go
index 73351ab2c..82c7497ba 100644
--- a/proto/go/gitalypb/repository_grpc.pb.go
+++ b/proto/go/gitalypb/repository_grpc.pb.go
@@ -53,7 +53,13 @@ type RepositoryServiceClient interface {
 	WriteRef(ctx context.Context, in *WriteRefRequest, opts ...grpc.CallOption) (*WriteRefResponse, error)
 	// This comment is left unintentionally blank.
 	FindMergeBase(ctx context.Context, in *FindMergeBaseRequest, opts ...grpc.CallOption) (*FindMergeBaseResponse, error)
-	// This comment is left unintentionally blank.
+	// CreateFork creates a new repository from a specific source repository. This new repository will
+	// have the same branches and tags as the source repository. Internal references will not be
+	// recreated in the forked repository.
+	//
+	// All objects of the source repository will be duplicated, that is there are no space savings by
+	// creating the repository like this. The newly created repository does not join the object pool
+	// of the source repository, if there is any.
 	CreateFork(ctx context.Context, in *CreateForkRequest, opts ...grpc.CallOption) (*CreateForkResponse, error)
 	// This comment is left unintentionally blank.
 	CreateRepositoryFromURL(ctx context.Context, in *CreateRepositoryFromURLRequest, opts ...grpc.CallOption) (*CreateRepositoryFromURLResponse, error)
@@ -917,7 +923,13 @@ type RepositoryServiceServer interface {
 	WriteRef(context.Context, *WriteRefRequest) (*WriteRefResponse, error)
 	// This comment is left unintentionally blank.
 	FindMergeBase(context.Context, *FindMergeBaseRequest) (*FindMergeBaseResponse, error)
-	// This comment is left unintentionally blank.
+	// CreateFork creates a new repository from a specific source repository. This new repository will
+	// have the same branches and tags as the source repository. Internal references will not be
+	// recreated in the forked repository.
+	//
+	// All objects of the source repository will be duplicated, that is there are no space savings by
+	// creating the repository like this. The newly created repository does not join the object pool
+	// of the source repository, if there is any.
 	CreateFork(context.Context, *CreateForkRequest) (*CreateForkResponse, error)
 	// This comment is left unintentionally blank.
 	CreateRepositoryFromURL(context.Context, *CreateRepositoryFromURLRequest) (*CreateRepositoryFromURLResponse, error)
diff --git a/proto/repository.proto b/proto/repository.proto
index da8027c81..324619d8a 100644
--- a/proto/repository.proto
+++ b/proto/repository.proto
@@ -106,7 +106,13 @@ service RepositoryService {
     };
   }
 
-  // This comment is left unintentionally blank.
+  // CreateFork creates a new repository from a specific source repository. This new repository will
+  // have the same branches and tags as the source repository. Internal references will not be
+  // recreated in the forked repository.
+  //
+  // All objects of the source repository will be duplicated, that is there are no space savings by
+  // creating the repository like this. The newly created repository does not join the object pool
+  // of the source repository, if there is any.
   rpc CreateFork(CreateForkRequest) returns (CreateForkResponse) {
     option (op_type) = {
       op: MUTATOR
@@ -653,15 +659,19 @@ message FindMergeBaseResponse {
   string base = 1;
 }
 
-// This comment is left unintentionally blank.
+// CreateForkRequest is a request for the CreateFork RPC.
 message CreateForkRequest {
-  // This comment is left unintentionally blank.
+  // Repository is the repository that shall be created.
   Repository repository = 1 [(target_repository)=true];
-  // This comment is left unintentionally blank.
+  // SourceRepository is the repository that shall be forked.
+  //
+  // Note that the source repository is intentionally not marked as an additional repository that is
+  // to be rewritten by Praefect. This is because Gitaly will use the source repository to perform a
+  // gRPC call, which must use the original non-rewritten repository.
   Repository source_repository = 2;
 }
 
-// This comment is left unintentionally blank.
+// CreateForkResponse is a response for the CreateFork RPC.
 message CreateForkResponse {
 }