Streams (#47)

* Streams Service (WIP)

* Complete Streams Service

streams/handler/list_messages_test.go

@@ -0,0 +1,116 @@
+package handler_test
+
+import (
+	"context"
+	"sort"
+	"strconv"
+	"testing"
+	"time"
+
+	"github.com/google/uuid"
+	"github.com/micro/services/streams/handler"
+	pb "github.com/micro/services/streams/proto"
+	"github.com/stretchr/testify/assert"
+	"google.golang.org/protobuf/types/known/wrapperspb"
+)
+
+func TestListMessages(t *testing.T) {
+	h := testHandler(t)
+	h.Time = time.Now
+
+	// seed some data
+	var convRsp pb.CreateConversationResponse
+	err := h.CreateConversation(context.TODO(), &pb.CreateConversationRequest{
+		Topic: "TestListMessages", GroupId: uuid.New().String(),
+	}, &convRsp)
+	assert.NoError(t, err)
+	if err != nil {
+		return
+	}
+
+	msgs := make([]*pb.Message, 50)
+	for i := 0; i < len(msgs); i++ {
+		var rsp pb.CreateMessageResponse
+		err := h.CreateMessage(context.TODO(), &pb.CreateMessageRequest{
+			ConversationId: convRsp.Conversation.Id,
+			AuthorId:       uuid.New().String(),
+			Text:           strconv.Itoa(i),
+		}, &rsp)
+		assert.NoError(t, err)
+		msgs[i] = rsp.Message
+	}
+
+	t.Run("MissingConversationID", func(t *testing.T) {
+		var rsp pb.ListMessagesResponse
+		err := h.ListMessages(context.TODO(), &pb.ListMessagesRequest{}, &rsp)
+		assert.Equal(t, handler.ErrMissingConversationID, err)
+		assert.Nil(t, rsp.Messages)
+	})
+
+	t.Run("NoOffset", func(t *testing.T) {
+		var rsp pb.ListMessagesResponse
+		err := h.ListMessages(context.TODO(), &pb.ListMessagesRequest{
+			ConversationId: convRsp.Conversation.Id,
+		}, &rsp)
+		assert.NoError(t, err)
+
+		if len(rsp.Messages) != handler.DefaultLimit {
+			t.Fatalf("Expected %v messages but got %v", handler.DefaultLimit, len(rsp.Messages))
+			return
+		}
+		expected := msgs[25:]
+		sortMessages(rsp.Messages)
+		for i, msg := range rsp.Messages {
+			assertMessagesMatch(t, expected[i], msg)
+		}
+	})
+
+	t.Run("LimitSet", func(t *testing.T) {
+		var rsp pb.ListMessagesResponse
+		err := h.ListMessages(context.TODO(), &pb.ListMessagesRequest{
+			ConversationId: convRsp.Conversation.Id,
+			Limit:          &wrapperspb.Int32Value{Value: 10},
+		}, &rsp)
+		assert.NoError(t, err)
+
+		if len(rsp.Messages) != 10 {
+			t.Fatalf("Expected %v messages but got %v", 10, len(rsp.Messages))
+			return
+		}
+		expected := msgs[40:]
+		sortMessages(rsp.Messages)
+		for i, msg := range rsp.Messages {
+			assertMessagesMatch(t, expected[i], msg)
+		}
+	})
+
+	t.Run("OffsetAndLimit", func(t *testing.T) {
+		var rsp pb.ListMessagesResponse
+		err := h.ListMessages(context.TODO(), &pb.ListMessagesRequest{
+			ConversationId: convRsp.Conversation.Id,
+			Limit:          &wrapperspb.Int32Value{Value: 5},
+			SentBefore:     msgs[20].SentAt,
+		}, &rsp)
+		assert.NoError(t, err)
+
+		if len(rsp.Messages) != 5 {
+			t.Fatalf("Expected %v messages but got %v", 5, len(rsp.Messages))
+			return
+		}
+		expected := msgs[15:20]
+		sortMessages(rsp.Messages)
+		for i, msg := range rsp.Messages {
+			assertMessagesMatch(t, expected[i], msg)
+		}
+	})
+}
+
+// sortMessages by the time they were sent
+func sortMessages(msgs []*pb.Message) {
+	sort.Slice(msgs, func(i, j int) bool {
+		if msgs[i].SentAt == nil || msgs[j].SentAt == nil {
+			return true
+		}
+		return msgs[i].SentAt.AsTime().Before(msgs[j].SentAt.AsTime())
+	})
+}