Propagate feature flags through gitaly-hooks

Hooks currently do not receive nor propagate the feature flags. This
is due to hooks being called through Git, which breaks the context
chain and thus the propagation. This commits propagate the feature
flags through the hooks to Gitaly's HookService. The feature flags
are added to the hook payload in order to pass them to the hooks.
The provided feature flags are then propagated via the outgoing context
to the HookService.

2 files changed, 61 insertions, 9 deletions

diff --git a/cmd/gitaly-hooks/hooks.go b/cmd/gitaly-hooks/hooks.go
index 70ea5d83e..ffd61ead9 100644
--- a/cmd/gitaly-hooks/hooks.go
+++ b/cmd/gitaly-hooks/hooks.go
@@ -17,6 +17,7 @@ import (
 	"gitlab.com/gitlab-org/gitaly/internal/gitaly/config"
 	"gitlab.com/gitlab-org/gitaly/internal/gitaly/hook"
 	gitalylog "gitlab.com/gitlab-org/gitaly/internal/log"
+	"gitlab.com/gitlab-org/gitaly/internal/metadata/featureflag"
 	"gitlab.com/gitlab-org/gitaly/internal/stream"
 	"gitlab.com/gitlab-org/gitaly/proto/go/gitalypb"
 	"gitlab.com/gitlab-org/gitaly/streamio"
@@ -120,6 +121,7 @@ func main() {
 	}
 	hookClient := gitalypb.NewHookServiceClient(conn)
 
+	ctx = featureflag.OutgoingWithRaw(ctx, payload.FeatureFlags)
 	returnCode, err := hookCommand.exec(ctx, payload, hookClient, os.Args)
 	if err != nil {
 		logger.Fatal(err)
diff --git a/cmd/gitaly-hooks/hooks_test.go b/cmd/gitaly-hooks/hooks_test.go
index d2e0ffa8f..de1633e95 100644
--- a/cmd/gitaly-hooks/hooks_test.go
+++ b/cmd/gitaly-hooks/hooks_test.go
@@ -2,6 +2,7 @@ package main
 
 import (
 	"bytes"
+	"context"
 	"encoding/json"
 	"fmt"
 	"io/ioutil"
@@ -13,6 +14,7 @@ import (
 	"strings"
 	"testing"
 
+	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	"gitlab.com/gitlab-org/gitaly/internal/backchannel"
 	"gitlab.com/gitlab-org/gitaly/internal/command"
@@ -25,6 +27,7 @@ import (
 	"gitlab.com/gitlab-org/gitaly/internal/gitaly/service/hook"
 	"gitlab.com/gitlab-org/gitaly/internal/gitaly/transaction"
 	gitalylog "gitlab.com/gitlab-org/gitaly/internal/log"
+	"gitlab.com/gitlab-org/gitaly/internal/metadata/featureflag"
 	"gitlab.com/gitlab-org/gitaly/internal/praefect/metadata"
 	"gitlab.com/gitlab-org/gitaly/internal/testhelper"
 	"gitlab.com/gitlab-org/gitaly/internal/testhelper/testcfg"
@@ -41,13 +44,22 @@ type proxyValues struct {
 	HTTPProxy, HTTPSProxy, NoProxy string
 }
 
+var enabledFeatureFlag = featureflag.FeatureFlag{Name: "enabled-feature-flag", OnByDefault: false}
+var disabledFeatureFlag = featureflag.FeatureFlag{Name: "disabled-feature-flag", OnByDefault: true}
+
+func rawFeatureFlags() featureflag.Raw {
+	ctx := featureflag.IncomingCtxWithFeatureFlag(context.Background(), enabledFeatureFlag)
+	ctx = featureflag.IncomingCtxWithDisabledFeatureFlag(ctx, disabledFeatureFlag)
+	return featureflag.RawFromContext(ctx)
+}
+
 // envForHooks generates a set of environment variables for gitaly hooks
 func envForHooks(t testing.TB, cfg config.Cfg, repo *gitalypb.Repository, glHookValues glHookValues, proxyValues proxyValues, gitPushOptions ...string) []string {
 	payload, err := git.NewHooksPayload(cfg, repo, nil, nil, &git.ReceiveHooksPayload{
 		UserID:   glHookValues.GLID,
 		Username: glHookValues.GLUsername,
 		Protocol: glHookValues.GLProtocol,
-	}, git.AllHooks).Env()
+	}, git.AllHooks, rawFeatureFlags()).Env()
 	require.NoError(t, err)
 
 	env := append(os.Environ(), []string{
@@ -344,9 +356,6 @@ func TestHooksPostReceiveFailed(t *testing.T) {
 	gitlabAPI, err := gitalyhook.NewGitlabAPI(cfg.Gitlab, cfg.TLS)
 	require.NoError(t, err)
 
-	stop := runHookServiceServerWithAPI(t, cfg, gitlabAPI)
-	defer stop()
-
 	customHookOutputPath := gittest.WriteEnvToCustomHook(t, repoPath, "post-receive")
 
 	var stdout, stderr bytes.Buffer
@@ -389,6 +398,9 @@ func TestHooksPostReceiveFailed(t *testing.T) {
 
 	for _, tc := range testcases {
 		t.Run(tc.desc, func(t *testing.T) {
+			stop := runHookServiceServerWithAPI(t, cfg, gitlabAPI)
+			defer stop()
+
 			hooksPayload, err := git.NewHooksPayload(
 				cfg,
 				repo,
@@ -407,6 +419,7 @@ func TestHooksPostReceiveFailed(t *testing.T) {
 					Protocol: glProtocol,
 				},
 				git.PostReceiveHook,
+				rawFeatureFlags(),
 			).Env()
 			require.NoError(t, err)
 
@@ -572,6 +585,41 @@ func runHookServiceServer(t *testing.T, cfg config.Cfg) func() {
 	return runHookServiceServerWithAPI(t, cfg, gitalyhook.GitlabAPIStub)
 }
 
+type featureFlagAsserter struct {
+	t       testing.TB
+	wrapped gitalypb.HookServiceServer
+}
+
+func (svc featureFlagAsserter) assertFlags(ctx context.Context) {
+	assert.True(svc.t, featureflag.IsEnabled(ctx, enabledFeatureFlag))
+	assert.True(svc.t, featureflag.IsDisabled(ctx, disabledFeatureFlag))
+}
+
+func (svc featureFlagAsserter) PreReceiveHook(stream gitalypb.HookService_PreReceiveHookServer) error {
+	svc.assertFlags(stream.Context())
+	return svc.wrapped.PreReceiveHook(stream)
+}
+
+func (svc featureFlagAsserter) PostReceiveHook(stream gitalypb.HookService_PostReceiveHookServer) error {
+	svc.assertFlags(stream.Context())
+	return svc.wrapped.PostReceiveHook(stream)
+}
+
+func (svc featureFlagAsserter) UpdateHook(request *gitalypb.UpdateHookRequest, stream gitalypb.HookService_UpdateHookServer) error {
+	svc.assertFlags(stream.Context())
+	return svc.wrapped.UpdateHook(request, stream)
+}
+
+func (svc featureFlagAsserter) ReferenceTransactionHook(stream gitalypb.HookService_ReferenceTransactionHookServer) error {
+	svc.assertFlags(stream.Context())
+	return svc.wrapped.ReferenceTransactionHook(stream)
+}
+
+func (svc featureFlagAsserter) PackObjectsHook(stream gitalypb.HookService_PackObjectsHookServer) error {
+	svc.assertFlags(stream.Context())
+	return svc.wrapped.PackObjectsHook(stream)
+}
+
 func runHookServiceServerWithAPI(t *testing.T, cfg config.Cfg, gitlabAPI gitalyhook.GitlabAPI) func() {
 	registry := backchannel.NewRegistry()
 	txManager := transaction.NewManager(cfg, registry)
@@ -579,7 +627,9 @@ func runHookServiceServerWithAPI(t *testing.T, cfg config.Cfg, gitlabAPI gitalyh
 	gitCmdFactory := git.NewExecCommandFactory(cfg)
 	server := testhelper.NewServerWithAuth(t, nil, nil, cfg.Auth.Token, registry, testhelper.WithInternalSocket(cfg))
 
-	gitalypb.RegisterHookServiceServer(server.GrpcServer(), hook.NewServer(cfg, hookManager, gitCmdFactory))
+	gitalypb.RegisterHookServiceServer(server.GrpcServer(), featureFlagAsserter{
+		t: t, wrapped: hook.NewServer(cfg, hookManager, gitCmdFactory),
+	})
 	reflection.Register(server.GrpcServer())
 	server.Start(t)
 
@@ -622,8 +672,6 @@ func TestGitalyHooksPackObjects(t *testing.T) {
 	testhelper.ConfigureGitalyHooksBin(t, cfg)
 	testhelper.ConfigureGitalySSHBin(t, cfg)
 
-	defer runHookServiceServer(t, cfg)()
-
 	env := envForHooks(t, cfg, repo, glHookValues{}, proxyValues{})
 
 	baseArgs := []string{
@@ -647,6 +695,8 @@ func TestGitalyHooksPackObjects(t *testing.T) {
 
 	for _, tc := range testCases {
 		t.Run(tc.desc, func(t *testing.T) {
+			defer runHookServiceServer(t, cfg)()
+
 			tempDir, cleanTempDir := testhelper.TempDir(t)
 			defer cleanTempDir()
 
@@ -675,7 +725,7 @@ func TestRequestedHooks(t *testing.T) {
 				testhelper.ConfigureGitalyHooksBin(t, cfg)
 				testhelper.ConfigureGitalySSHBin(t, cfg)
 
-				payload, err := git.NewHooksPayload(cfg, &gitalypb.Repository{}, nil, nil, nil, git.AllHooks&^hook).Env()
+				payload, err := git.NewHooksPayload(cfg, &gitalypb.Repository{}, nil, nil, nil, git.AllHooks&^hook, nil).Env()
 				require.NoError(t, err)
 
 				cmd := exec.Command(filepath.Join(cfg.BinDir, "gitaly-hooks"), hookName)
@@ -688,7 +738,7 @@ func TestRequestedHooks(t *testing.T) {
 				testhelper.ConfigureGitalyHooksBin(t, cfg)
 				testhelper.ConfigureGitalySSHBin(t, cfg)
 
-				payload, err := git.NewHooksPayload(cfg, &gitalypb.Repository{}, nil, nil, nil, hook).Env()
+				payload, err := git.NewHooksPayload(cfg, &gitalypb.Repository{}, nil, nil, nil, hook, nil).Env()
 				require.NoError(t, err)
 
 				cmd := exec.Command(filepath.Join(cfg.BinDir, "gitaly-hooks"), hookName)