ccl/sqlproxyccl: rename tenant.Resolver to tenant.Directory

This commit completes the work of making tenant.Directory an interface.
Since we have renamed the previous Directory struct into a serviceDirectory
struct, we can now use Directory as an interface for what was previously known
as the resolver.

Release note: None

pkg/ccl/sqlproxyccl/connector.go

@@ -48,10 +48,8 @@ type connector struct {
 	// Directory corresponds to the tenant directory, which will be used to
 	// resolve tenants to their corresponding IP addresses.
 	//
-	// TODO(jaylim-crl): Replace this with a Directory interface.
-	//
 	// NOTE: This field is required.
-	Directory tenant.Resolver
+	Directory tenant.Directory
 
 	// StartupMsg represents the startup message associated with the client.
 	// This will be used when establishing a pgwire connection with the SQL pod.
@@ -342,7 +340,7 @@ func isRetriableConnectorError(err error) bool {
 // reportFailureToDirectory is a hookable function that calls the given tenant
 // directory's ReportFailure method.
 var reportFailureToDirectory = func(
-	ctx context.Context, tenantID roachpb.TenantID, addr string, directory tenant.Resolver,
+	ctx context.Context, tenantID roachpb.TenantID, addr string, directory tenant.Directory,
 ) error {
 	return directory.ReportFailure(ctx, tenantID, addr)
 }

pkg/ccl/sqlproxyccl/connector_test.go

@@ -435,7 +435,7 @@ func TestConnector_dialTenantCluster(t *testing.T) {
 		c := &connector{
 			TenantID: roachpb.MakeTenantID(42),
 		}
-		c.Directory = &testResolver{
+		c.Directory = &testDirectory{
 			reportFailureFn: func(fnCtx context.Context, tenantID roachpb.TenantID, addr string) error {
 				reportFailureFnCount++
 				require.Equal(t, ctx, fnCtx)
@@ -485,7 +485,7 @@ func TestConnector_lookupAddr(t *testing.T) {
 		c = &connector{
 			ClusterName: "my-foo",
 			TenantID:    roachpb.MakeTenantID(10),
-			Directory: &testResolver{
+			Directory: &testDirectory{
 				ensureTenantAddrFn: func(fnCtx context.Context, tenantID roachpb.TenantID, clusterName string) (string, error) {
 					ensureTenantAddrFnCount++
 					require.Equal(t, ctx, fnCtx)
@@ -508,7 +508,7 @@ func TestConnector_lookupAddr(t *testing.T) {
 		c = &connector{
 			ClusterName: "my-foo",
 			TenantID:    roachpb.MakeTenantID(10),
-			Directory: &testResolver{
+			Directory: &testDirectory{
 				ensureTenantAddrFn: func(fnCtx context.Context, tenantID roachpb.TenantID, clusterName string) (string, error) {
 					ensureTenantAddrFnCount++
 					require.Equal(t, ctx, fnCtx)
@@ -531,7 +531,7 @@ func TestConnector_lookupAddr(t *testing.T) {
 		c = &connector{
 			ClusterName: "my-foo",
 			TenantID:    roachpb.MakeTenantID(10),
-			Directory: &testResolver{
+			Directory: &testDirectory{
 				ensureTenantAddrFn: func(fnCtx context.Context, tenantID roachpb.TenantID, clusterName string) (string, error) {
 					ensureTenantAddrFnCount++
 					require.Equal(t, ctx, fnCtx)
@@ -554,7 +554,7 @@ func TestConnector_lookupAddr(t *testing.T) {
 		c = &connector{
 			ClusterName: "my-foo",
 			TenantID:    roachpb.MakeTenantID(10),
-			Directory: &testResolver{
+			Directory: &testDirectory{
 				ensureTenantAddrFn: func(fnCtx context.Context, tenantID roachpb.TenantID, clusterName string) (string, error) {
 					ensureTenantAddrFnCount++
 					require.Equal(t, ctx, fnCtx)
@@ -674,31 +674,31 @@ func TestRetriableConnectorError(t *testing.T) {
 	require.True(t, errors.Is(err, errRetryConnectorSentinel))
 }
 
-var _ tenant.Resolver = &testResolver{}
+var _ tenant.Directory = &testDirectory{}
 
-// testResolver is a test implementation of the tenant resolver.
-type testResolver struct {
+// testDirectory is a test implementation of the tenant resolver.
+type testDirectory struct {
 	ensureTenantAddrFn  func(ctx context.Context, tenantID roachpb.TenantID, clusterName string) (string, error)
 	lookupTenantAddrsFn func(ctx context.Context, tenantID roachpb.TenantID) ([]string, error)
 	reportFailureFn     func(ctx context.Context, tenantID roachpb.TenantID, addr string) error
 }
 
 // EnsureTenantAddr implements the Resolver interface.
-func (r *testResolver) EnsureTenantAddr(
+func (r *testDirectory) EnsureTenantAddr(
 	ctx context.Context, tenantID roachpb.TenantID, clusterName string,
 ) (string, error) {
 	return r.ensureTenantAddrFn(ctx, tenantID, clusterName)
 }
 
 // LookupTenantAddrs implements the Resolver interface.
-func (r *testResolver) LookupTenantAddrs(
+func (r *testDirectory) LookupTenantAddrs(
 	ctx context.Context, tenantID roachpb.TenantID,
 ) ([]string, error) {
 	return r.lookupTenantAddrsFn(ctx, tenantID)
 }
 
 // ReportFailure implements the Resolver interface.
-func (r *testResolver) ReportFailure(
+func (r *testDirectory) ReportFailure(
 	ctx context.Context, tenantID roachpb.TenantID, addr string,
 ) error {
 	return r.reportFailureFn(ctx, tenantID, addr)

pkg/ccl/sqlproxyccl/proxy_handler.go

@@ -79,7 +79,7 @@ type ProxyOptions struct {
 	// connection.
 	RoutingRule string
 	// DirectoryAddr specified optional {HOSTNAME}:{PORT} for service that does
-	// the resolution from backend id to IP address. If specified - it will be
+	// the resolution from tenants to IP addresses. If specified - it will be
 	// used instead of the routing rule above.
 	DirectoryAddr string
 	// RatelimitBaseDelay is the initial backoff after a failed login attempt.
@@ -127,8 +127,8 @@ type proxyHandler struct {
 	// idleMonitor will detect idle connections to DRAINING pods.
 	idleMonitor *idle.Monitor
 
-	// directory is used to resolve backend id to IP addresses.
-	directory tenant.Resolver
+	// directory is used to resolve tenants to their corresponding IP addresses.
+	directory tenant.Directory
 
 	// CertManger keeps up to date the certificates used.
 	certManager *certmgr.CertManager

pkg/ccl/sqlproxyccl/proxy_handler_test.go

@@ -689,7 +689,7 @@ func TestDirectoryConnect(t *testing.T) {
 		// Ensure that Directory.ReportFailure is being called correctly.
 		countReports := 0
 		defer testutils.TestingHook(&reportFailureToDirectory, func(
-			ctx context.Context, tenantID roachpb.TenantID, addr string, directory tenant.Resolver,
+			ctx context.Context, tenantID roachpb.TenantID, addr string, directory tenant.Directory,
 		) error {
 			require.Equal(t, roachpb.MakeTenantID(28), tenantID)
 			addrs, err := directory.LookupTenantAddrs(ctx, tenantID)

pkg/ccl/sqlproxyccl/tenant/BUILD.bazel

@@ -3,7 +3,7 @@ load("@io_bazel_rules_go//go:def.bzl", "go_library")
 
 go_library(
     name = "tenant",
-    srcs = ["resolver.go"],
+    srcs = ["directory.go"],
     importpath = "github.com/cockroachdb/cockroach/pkg/ccl/sqlproxyccl/tenant",
     visibility = ["//visibility:public"],
     deps = ["//pkg/roachpb"],

pkg/ccl/sqlproxyccl/tenant/resolver.go → pkg/ccl/sqlproxyccl/tenant/directory.go

@@ -14,11 +14,8 @@ import (
 	"github.com/cockroachdb/cockroach/pkg/roachpb"
 )
 
-// Resolver is an interface for the tenant directory.
-//
-// TODO(jaylim-crl): Rename this to Directory, and the current tenant.Directory
-// to tenant.directory.
-type Resolver interface {
+// Directory is an interface for the tenant directory.
+type Directory interface {
 	// EnsureTenantAddr returns an IP address of one of the given tenant's SQL
 	// processes based on the tenantID and clusterName fields. This should block
 	// until the process associated with the IP is ready.

pkg/ccl/sqlproxyccl/tenant/servicedir/service_directory.go

@@ -99,6 +99,8 @@ type serviceDirectory struct {
 	}
 }
 
+var _ tenant.Directory = &serviceDirectory{}
+
 // NewServiceDirectory constructs a new serviceDirectory instance that tracks
 // SQL tenant processes managed by a given Directory server. The given context
 // is used for tracing pod watcher activity.
@@ -107,7 +109,7 @@ type serviceDirectory struct {
 // needed.
 func NewServiceDirectory(
 	ctx context.Context, stopper *stop.Stopper, client DirectoryClient, opts ...DirOption,
-) (tenant.Resolver, error) {
+) (tenant.Directory, error) {
 	dir := &serviceDirectory{client: client, stopper: stopper}
 
 	dir.mut.tenants = make(map[roachpb.TenantID]*tenantEntry)
@@ -140,6 +142,8 @@ func NewServiceDirectory(
 // such as the name of the cluster, before being allowed to connect. Similarly,
 // if the tenant does not exist (e.g. because it was deleted), EnsureTenantAddr
 // returns a GRPC NotFound error.
+//
+// EnsureTenantAddr implements the tenant.Directory interface.
 func (d *serviceDirectory) EnsureTenantAddr(
 	ctx context.Context, tenantID roachpb.TenantID, clusterName string,
 ) (string, error) {
@@ -173,6 +177,8 @@ func (d *serviceDirectory) EnsureTenantAddr(
 // into the directory's cache (LookupTenantAddrs will never attempt to fetch it).
 // If no processes are available for the tenant, LookupTenantAddrs will return the
 // empty set (unlike EnsureTenantAddr).
+//
+// LookupTenantAddrs implements the tenant.Directory interface.
 func (d *serviceDirectory) LookupTenantAddrs(
 	ctx context.Context, tenantID roachpb.TenantID,
 ) ([]string, error) {
@@ -203,6 +209,8 @@ func (d *serviceDirectory) LookupTenantAddrs(
 // particular pod as "unhealthy" so that it's less likely to be chosen.
 // However, today there can be at most one pod for a given tenant, so it
 // must always be chosen. Keep the parameter as a placeholder for the future.
+//
+// ReportFailure implements the tenant.Directory interface.
 func (d *serviceDirectory) ReportFailure(
 	ctx context.Context, tenantID roachpb.TenantID, addr string,
 ) error {

pkg/ccl/sqlproxyccl/tenant/servicedir/service_directory_test.go

@@ -519,7 +519,7 @@ func newTestDirectory(
 	t *testing.T, opts ...servicedir.DirOption,
 ) (
 	tc serverutils.TestClusterInterface,
-	directory tenant.Resolver,
+	directory tenant.Directory,
 	tds *tenantdirsvr.TestDirectoryServer,
 ) {
 	tc = serverutils.StartNewTestCluster(t, 1, base.TestClusterArgs{

pkg/ccl/sqlproxyccl/tenant/simpledir/simple_directory.go

@@ -27,18 +27,18 @@ type simpleDirectory struct {
 	podAddr string
 }
 
-var _ tenant.Resolver = &simpleDirectory{}
+var _ tenant.Directory = &simpleDirectory{}
 
 // NewSimpleDirectory constructs a new simple directory instance that abides to
-// the Resolver interface.
-func NewSimpleDirectory(podAddr string) tenant.Resolver {
+// the tenant.Directory interface.
+func NewSimpleDirectory(podAddr string) tenant.Directory {
 	return &simpleDirectory{podAddr: podAddr}
 }
 
 // EnsureTenantAddr returns the SQL pod address associated with this directory.
 // If the address cannot be resolved, a GRPC NotFound error will be returned.
 //
-// EnsureTenantAddr implements the Resolver interface.
+// EnsureTenantAddr implements the tenant.Directory interface.
 func (d *simpleDirectory) EnsureTenantAddr(
 	ctx context.Context, tenantID roachpb.TenantID, clusterName string,
 ) (string, error) {
@@ -52,7 +52,7 @@ func (d *simpleDirectory) EnsureTenantAddr(
 // of tenantID. If that address cannot be resolved, a GRPC NotFound error will
 // be returned.
 //
-// LookupTenantAddrs implements the Resolver interface.
+// LookupTenantAddrs implements the tenant.Directory interface.
 func (d *simpleDirectory) LookupTenantAddrs(
 	ctx context.Context, tenantID roachpb.TenantID,
 ) ([]string, error) {
@@ -64,7 +64,7 @@ func (d *simpleDirectory) LookupTenantAddrs(
 
 // ReportFailure is a no-op for the simple directory.
 //
-// ReportFailure implements the Resolver interface.
+// ReportFailure implements the tenant.Directory interface.
 func (d *simpleDirectory) ReportFailure(
 	ctx context.Context, tenantID roachpb.TenantID, addr string,
 ) error {

pkg/cli/cliflags/flags_mt.go

@@ -61,7 +61,7 @@ var (
 
 	DirectoryAddr = FlagInfo{
 		Name:        "directory",
-		Description: "Directory address of the service doing resolution from backend id to IP.",
+		Description: "Directory address of the service doing resolution of tenants to their IP addresses.",
 	}
 
 	// TODO(chrisseto): Remove skip-verify as a CLI option. It should only be