Add tests for SpectatorPeerChooser

Tests cover:
- Success path with peer creation
- Peer reuse on subsequent calls
- Error cases (missing shard key, namespace header, spectator not found)
- Lifecycle methods (Start, Stop, IsRunning)
- SetSpectators method

Signed-off-by: Jakob Haahr Taankvist <[email protected]>

Author: jakobht

service/sharddistributor/client/spectatorclient/peer_chooser_test.go

@@ -0,0 +1,185 @@
+package spectatorclient
+
+import (
+	"context"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	"go.uber.org/mock/gomock"
+	"go.uber.org/yarpc/api/peer"
+	"go.uber.org/yarpc/api/transport"
+	"go.uber.org/yarpc/transport/grpc"
+
+	"github.com/uber/cadence/common/log/testlogger"
+)
+
+func TestSpectatorPeerChooser_Choose_MissingShardKey(t *testing.T) {
+	chooser := &SpectatorPeerChooser{
+		logger: testlogger.New(t),
+		peers:  make(map[string]peer.Peer),
+	}
+
+	req := &transport.Request{
+		ShardKey: "",
+		Headers:  transport.NewHeaders(),
+	}
+
+	p, onFinish, err := chooser.Choose(context.Background(), req)
+
+	assert.Error(t, err)
+	assert.Nil(t, p)
+	assert.Nil(t, onFinish)
+	assert.Contains(t, err.Error(), "ShardKey")
+}
+
+func TestSpectatorPeerChooser_Choose_MissingNamespaceHeader(t *testing.T) {
+	chooser := &SpectatorPeerChooser{
+		logger: testlogger.New(t),
+		peers:  make(map[string]peer.Peer),
+	}
+
+	req := &transport.Request{
+		ShardKey: "shard-1",
+		Headers:  transport.NewHeaders(),
+	}
+
+	p, onFinish, err := chooser.Choose(context.Background(), req)
+
+	assert.Error(t, err)
+	assert.Nil(t, p)
+	assert.Nil(t, onFinish)
+	assert.Contains(t, err.Error(), "x-shard-distributor-namespace")
+}
+
+func TestSpectatorPeerChooser_Choose_SpectatorNotFound(t *testing.T) {
+	chooser := &SpectatorPeerChooser{
+		logger:     testlogger.New(t),
+		peers:      make(map[string]peer.Peer),
+		spectators: make(Spectators),
+	}
+
+	req := &transport.Request{
+		ShardKey: "shard-1",
+		Headers:  transport.NewHeaders().With(NamespaceHeader, "unknown-namespace"),
+	}
+
+	p, onFinish, err := chooser.Choose(context.Background(), req)
+
+	assert.Error(t, err)
+	assert.Nil(t, p)
+	assert.Nil(t, onFinish)
+	assert.Contains(t, err.Error(), "spectator not found")
+}
+
+func TestSpectatorPeerChooser_StartStop(t *testing.T) {
+	chooser := &SpectatorPeerChooser{
+		logger: testlogger.New(t),
+		peers:  make(map[string]peer.Peer),
+	}
+
+	err := chooser.Start()
+	require.NoError(t, err)
+
+	assert.True(t, chooser.IsRunning())
+
+	err = chooser.Stop()
+	assert.NoError(t, err)
+}
+
+func TestSpectatorPeerChooser_SetSpectators(t *testing.T) {
+	chooser := &SpectatorPeerChooser{
+		logger: testlogger.New(t),
+	}
+
+	spectators := make(Spectators)
+	chooser.SetSpectators(spectators)
+
+	assert.Equal(t, spectators, chooser.spectators)
+}
+
+func TestSpectatorPeerChooser_Choose_Success(t *testing.T) {
+	ctrl := gomock.NewController(t)
+	defer ctrl.Finish()
+
+	mockSpectator := NewMockSpectator(ctrl)
+	peerTransport := grpc.NewTransport()
+
+	chooser := &SpectatorPeerChooser{
+		transport: peerTransport,
+		logger:    testlogger.New(t),
+		peers:     make(map[string]peer.Peer),
+		spectators: Spectators{
+			"test-namespace": mockSpectator,
+		},
+	}
+
+	ctx := context.Background()
+	req := &transport.Request{
+		ShardKey: "shard-1",
+		Headers:  transport.NewHeaders().With(NamespaceHeader, "test-namespace"),
+	}
+
+	// Mock spectator to return shard owner with grpc_address
+	mockSpectator.EXPECT().
+		GetShardOwner(ctx, "shard-1").
+		Return(&ShardOwner{
+			ExecutorID: "executor-1",
+			Metadata: map[string]string{
+				grpcAddressMetadataKey: "127.0.0.1:7953",
+			},
+		}, nil)
+
+	// Execute
+	p, onFinish, err := chooser.Choose(ctx, req)
+
+	// Assert
+	assert.NoError(t, err)
+	assert.NotNil(t, p)
+	assert.NotNil(t, onFinish)
+	assert.Equal(t, "127.0.0.1:7953", p.Identifier())
+	assert.Len(t, chooser.peers, 1)
+}
+
+func TestSpectatorPeerChooser_Choose_ReusesPeer(t *testing.T) {
+	ctrl := gomock.NewController(t)
+	defer ctrl.Finish()
+
+	mockSpectator := NewMockSpectator(ctrl)
+	peerTransport := grpc.NewTransport()
+
+	chooser := &SpectatorPeerChooser{
+		transport: peerTransport,
+		logger:    testlogger.New(t),
+		peers:     make(map[string]peer.Peer),
+		spectators: Spectators{
+			"test-namespace": mockSpectator,
+		},
+	}
+
+	req := &transport.Request{
+		ShardKey: "shard-1",
+		Headers:  transport.NewHeaders().With(NamespaceHeader, "test-namespace"),
+	}
+
+	// First call creates the peer
+	mockSpectator.EXPECT().
+		GetShardOwner(gomock.Any(), "shard-1").
+		Return(&ShardOwner{
+			ExecutorID: "executor-1",
+			Metadata: map[string]string{
+				grpcAddressMetadataKey: "127.0.0.1:7953",
+			},
+		}, nil).Times(2)
+
+	firstPeer, _, err := chooser.Choose(context.Background(), req)
+	require.NoError(t, err)
+
+	// Second call should reuse the same peer
+	secondPeer, _, err := chooser.Choose(context.Background(), req)
+
+	// Assert - should reuse existing peer
+	assert.NoError(t, err)
+	assert.Equal(t, firstPeer, secondPeer)
+	assert.Len(t, chooser.peers, 1)
+}