#1: Split textures processing to 2 separate steps

api/mojang/queue/queue.go

@@ -44,10 +44,10 @@ func (ctx *JobsQueue) GetTexturesForUsername(username string) chan *mojang.Signe
 		return responseChan
 	}
 
-	cachedResult := ctx.Storage.Get(username)
+	uuid, err := ctx.Storage.GetUuid(username)
-	if cachedResult != nil {
+	if err == nil && uuid == "" {
 		go func() {
-			responseChan <- cachedResult
+			responseChan <- nil
 			close(responseChan)
 		}()
 
@@ -56,9 +56,16 @@ func (ctx *JobsQueue) GetTexturesForUsername(username string) chan *mojang.Signe
 
 	isFirstListener := ctx.broadcast.AddListener(username, responseChan)
 	if isFirstListener {
+		// TODO: respond nil if processing takes more than 5 seconds
+
 		resultChan := make(chan *mojang.SignedTexturesResponse)
+		if uuid == "" {
 			ctx.queue.Enqueue(&jobItem{username, resultChan})
-		// TODO: return nil if processing takes more than 5 seconds
+		} else {
+			go func() {
+				resultChan <- ctx.getTextures(uuid)
+			}()
+		}
 
 		go func() {
 			result := <-resultChan
@@ -108,9 +115,8 @@ func (ctx *JobsQueue) queueRound() {
 	for _, job := range jobs {
 		wg.Add(1)
 		go func(job *jobItem) {
-			var result *mojang.SignedTexturesResponse
-			shouldCache := true
 			var uuid string
+			// Profiles in response not ordered, so we must search each username over full array
 			for _, profile := range profiles {
 				if strings.EqualFold(job.Username, profile.Name) {
 					uuid = profile.Id
@@ -118,9 +124,28 @@ func (ctx *JobsQueue) queueRound() {
 				}
 			}
 
-			if uuid != "" {
+			ctx.Storage.StoreUuid(job.Username, uuid)
-				var err error
+			if uuid == "" {
-				result, err = uuidToTextures(uuid, true)
+				job.RespondTo <- nil
+			} else {
+				job.RespondTo <- ctx.getTextures(uuid)
+			}
+
+			wg.Done()
+		}(job)
+	}
+
+	wg.Wait()
+}
+
+func (ctx *JobsQueue) getTextures(uuid string) *mojang.SignedTexturesResponse {
+	existsTextures, err := ctx.Storage.GetTextures(uuid)
+	if err == nil {
+		return existsTextures
+	}
+
+	shouldCache := true
+	result, err := uuidToTextures(uuid, true)
 	if err != nil {
 		if _, ok := err.(*mojang.TooManyRequestsError); !ok {
 			panic(err)
@@ -128,17 +153,10 @@ func (ctx *JobsQueue) queueRound() {
 
 		shouldCache = false
 	}
-			}
-
-			wg.Done()
 
 	if shouldCache && result != nil {
-				ctx.Storage.Set(result)
+		ctx.Storage.StoreTextures(result)
 	}
 
-			job.RespondTo <- result
+	return result
-		}(job)
-	}
-
-	wg.Wait()
 }

api/mojang/queue/queue_test.go

@@ -3,14 +3,12 @@ package queue
 import (
 	"crypto/rand"
 	"encoding/base64"
-	"strings"
-	"time"
-
 	"github.com/elyby/chrly/api/mojang"
-
 	"github.com/stretchr/testify/mock"
 	"github.com/stretchr/testify/suite"
+	"strings"
 	"testing"
+	"time"
 )
 
 type MojangApiMocks struct {
@@ -41,17 +39,26 @@ type MockStorage struct {
 	mock.Mock
 }
 
-func (m *MockStorage) Get(username string) *mojang.SignedTexturesResponse {
+func (m *MockStorage) GetUuid(username string) (string, error) {
 	args := m.Called(username)
+	return args.String(0), args.Error(1)
+}
+
+func (m *MockStorage) StoreUuid(username string, uuid string) {
+	m.Called(username, uuid)
+}
+
+func (m *MockStorage) GetTextures(uuid string) (*mojang.SignedTexturesResponse, error) {
+	args := m.Called(uuid)
 	var result *mojang.SignedTexturesResponse
 	if casted, ok := args.Get(0).(*mojang.SignedTexturesResponse); ok {
 		result = casted
 	}
 
-	return result
+	return result, args.Error(1)
 }
 
-func (m *MockStorage) Set(textures *mojang.SignedTexturesResponse) {
+func (m *MockStorage) StoreTextures(textures *mojang.SignedTexturesResponse) {
 	m.Called(textures)
 }
 
@@ -99,11 +106,13 @@ func (suite *QueueTestSuite) TearDownTest() {
 	suite.Storage.AssertExpectations(suite.T())
 }
 
-func (suite *QueueTestSuite) TestReceiveTexturesForOneUsername() {
+func (suite *QueueTestSuite) TestReceiveTexturesForOneUsernameWithoutAnyCache() {
 	expectedResult := &mojang.SignedTexturesResponse{Id: "0d252b7218b648bfb86c2ae476954d32", Name: "maksimkurb"}
 
-	suite.Storage.On("Get", mock.Anything).Return(nil)
+	suite.Storage.On("GetUuid", "maksimkurb").Once().Return("", &ValueNotFound{})
-	suite.Storage.On("Set", expectedResult).Once()
+	suite.Storage.On("StoreUuid", "maksimkurb", "0d252b7218b648bfb86c2ae476954d32").Once()
+	suite.Storage.On("GetTextures", "0d252b7218b648bfb86c2ae476954d32").Once().Return(nil, &ValueNotFound{})
+	suite.Storage.On("StoreTextures", expectedResult).Once()
 	suite.MojangApi.On("UsernameToUuids", []string{"maksimkurb"}).Once().Return([]*mojang.ProfileInfo{
 		{Id: "0d252b7218b648bfb86c2ae476954d32", Name: "maksimkurb"},
 	}, nil)
@@ -117,13 +126,18 @@ func (suite *QueueTestSuite) TestReceiveTexturesForOneUsername() {
 	suite.Assert().Equal(expectedResult, result)
 }
 
-func (suite *QueueTestSuite) TestReceiveTexturesForFewUsernames() {
+func (suite *QueueTestSuite) TestReceiveTexturesForFewUsernamesWithoutAnyCache() {
 	expectedResult1 := &mojang.SignedTexturesResponse{Id: "0d252b7218b648bfb86c2ae476954d32", Name: "maksimkurb"}
 	expectedResult2 := &mojang.SignedTexturesResponse{Id: "4566e69fc90748ee8d71d7ba5aa00d20", Name: "Thinkofdeath"}
 
-	suite.Storage.On("Get", mock.Anything).Return(nil)
+	suite.Storage.On("GetUuid", "maksimkurb").Once().Return("", &ValueNotFound{})
-	suite.Storage.On("Set", expectedResult1).Once()
+	suite.Storage.On("GetUuid", "Thinkofdeath").Once().Return("", &ValueNotFound{})
-	suite.Storage.On("Set", expectedResult2).Once()
+	suite.Storage.On("StoreUuid", "maksimkurb", "0d252b7218b648bfb86c2ae476954d32").Once()
+	suite.Storage.On("StoreUuid", "Thinkofdeath", "4566e69fc90748ee8d71d7ba5aa00d20").Once()
+	suite.Storage.On("GetTextures", "0d252b7218b648bfb86c2ae476954d32").Once().Return(nil, &ValueNotFound{})
+	suite.Storage.On("GetTextures", "4566e69fc90748ee8d71d7ba5aa00d20").Once().Return(nil, &ValueNotFound{})
+	suite.Storage.On("StoreTextures", expectedResult1).Once()
+	suite.Storage.On("StoreTextures", expectedResult2).Once()
 	suite.MojangApi.On("UsernameToUuids", []string{"maksimkurb", "Thinkofdeath"}).Once().Return([]*mojang.ProfileInfo{
 		{Id: "0d252b7218b648bfb86c2ae476954d32", Name: "maksimkurb"},
 		{Id: "4566e69fc90748ee8d71d7ba5aa00d20", Name: "Thinkofdeath"},
@@ -140,14 +154,66 @@ func (suite *QueueTestSuite) TestReceiveTexturesForFewUsernames() {
 	suite.Assert().Equal(expectedResult2, <-resultChan2)
 }
 
+func (suite *QueueTestSuite) TestReceiveTexturesForUsernameWithCachedUuid() {
+	expectedResult := &mojang.SignedTexturesResponse{Id: "0d252b7218b648bfb86c2ae476954d32", Name: "maksimkurb"}
+
+	suite.Storage.On("GetUuid", "maksimkurb").Once().Return("0d252b7218b648bfb86c2ae476954d32", nil)
+	// Storage.StoreUuid shouldn't be called
+	suite.Storage.On("GetTextures", "0d252b7218b648bfb86c2ae476954d32").Once().Return(nil, &ValueNotFound{})
+	suite.Storage.On("StoreTextures", expectedResult).Once()
+	// MojangApi.UsernameToUuids shouldn't be called
+	suite.MojangApi.On("UuidToTextures", "0d252b7218b648bfb86c2ae476954d32", true).Once().Return(expectedResult, nil)
+
+	resultChan := suite.Queue.GetTexturesForUsername("maksimkurb")
+
+	// Note that there is no iteration
+
+	result := <-resultChan
+	suite.Assert().Equal(expectedResult, result)
+}
+
+func (suite *QueueTestSuite) TestReceiveTexturesForUsernameWithFullyCachedResult() {
+	expectedResult := &mojang.SignedTexturesResponse{Id: "0d252b7218b648bfb86c2ae476954d32", Name: "maksimkurb"}
+
+	suite.Storage.On("GetUuid", "maksimkurb").Once().Return("0d252b7218b648bfb86c2ae476954d32", nil)
+	// Storage.StoreUuid shouldn't be called
+	suite.Storage.On("GetTextures", "0d252b7218b648bfb86c2ae476954d32").Once().Return(expectedResult, nil)
+	// Storage.StoreTextures shouldn't be called
+	// MojangApi.UsernameToUuids shouldn't be called
+	// MojangApi.UuidToTextures shouldn't be called
+
+	resultChan := suite.Queue.GetTexturesForUsername("maksimkurb")
+
+	// Note that there is no iteration
+
+	result := <-resultChan
+	suite.Assert().Equal(expectedResult, result)
+}
+
+func (suite *QueueTestSuite) TestReceiveTexturesForUsernameWithCachedUnknownUuid() {
+	suite.Storage.On("GetUuid", "maksimkurb").Once().Return("", nil)
+	// Storage.StoreUuid shouldn't be called
+	// Storage.GetTextures shouldn't be called
+	// Storage.StoreTextures shouldn't be called
+	// MojangApi.UsernameToUuids shouldn't be called
+	// MojangApi.UuidToTextures shouldn't be called
+
+	resultChan := suite.Queue.GetTexturesForUsername("maksimkurb")
+
+	// Note that there is no iteration
+
+	suite.Assert().Nil(<-resultChan)
+}
+
 func (suite *QueueTestSuite) TestReceiveTexturesForMoreThan100Usernames() {
 	usernames := make([]string, 120, 120)
 	for i := 0; i < 120; i++ {
 		usernames[i] = randStr(8)
 	}
 
-	suite.Storage.On("Get", mock.Anything).Times(120).Return(nil)
+	suite.Storage.On("GetUuid", mock.Anything).Times(120).Return("", &ValueNotFound{})
-	// Storage.Set shouldn't be called
+	suite.Storage.On("StoreUuid", mock.Anything, "").Times(120) // if username is not compared to uuid, then receive ""
+	// Storage.GetTextures and Storage.SetTextures shouldn't be called
 	suite.MojangApi.On("UsernameToUuids", usernames[0:100]).Once().Return([]*mojang.ProfileInfo{}, nil)
 	suite.MojangApi.On("UsernameToUuids", usernames[100:120]).Once().Return([]*mojang.ProfileInfo{}, nil)
 
@@ -162,8 +228,10 @@ func (suite *QueueTestSuite) TestReceiveTexturesForMoreThan100Usernames() {
 func (suite *QueueTestSuite) TestReceiveTexturesForTheSameUsernames() {
 	expectedResult := &mojang.SignedTexturesResponse{Id: "0d252b7218b648bfb86c2ae476954d32", Name: "maksimkurb"}
 
-	suite.Storage.On("Get", mock.Anything).Twice().Return(nil)
+	suite.Storage.On("GetUuid", "maksimkurb").Twice().Return("", &ValueNotFound{})
-	suite.Storage.On("Set", expectedResult).Once()
+	suite.Storage.On("StoreUuid", "maksimkurb", "0d252b7218b648bfb86c2ae476954d32").Once()
+	suite.Storage.On("GetTextures", "0d252b7218b648bfb86c2ae476954d32").Once().Return(nil, &ValueNotFound{})
+	suite.Storage.On("StoreTextures", expectedResult).Once()
 	suite.MojangApi.On("UsernameToUuids", []string{"maksimkurb"}).Once().Return([]*mojang.ProfileInfo{
 		{Id: "0d252b7218b648bfb86c2ae476954d32", Name: "maksimkurb"},
 	}, nil)
@@ -181,8 +249,10 @@ func (suite *QueueTestSuite) TestReceiveTexturesForTheSameUsernames() {
 func (suite *QueueTestSuite) TestReceiveTexturesForUsernameThatAlreadyProcessing() {
 	expectedResult := &mojang.SignedTexturesResponse{Id: "0d252b7218b648bfb86c2ae476954d32", Name: "maksimkurb"}
 
-	suite.Storage.On("Get", mock.Anything).Return(nil)
+	suite.Storage.On("GetUuid", "maksimkurb").Twice().Return("", &ValueNotFound{})
-	suite.Storage.On("Set", expectedResult).Once()
+	suite.Storage.On("StoreUuid", "maksimkurb", "0d252b7218b648bfb86c2ae476954d32").Once()
+	suite.Storage.On("GetTextures", "0d252b7218b648bfb86c2ae476954d32").Once().Return(nil, &ValueNotFound{})
+	suite.Storage.On("StoreTextures", expectedResult).Once()
 	suite.MojangApi.On("UsernameToUuids", []string{"maksimkurb"}).Once().Return([]*mojang.ProfileInfo{
 		{Id: "0d252b7218b648bfb86c2ae476954d32", Name: "maksimkurb"},
 	}, nil)
@@ -206,8 +276,9 @@ func (suite *QueueTestSuite) TestReceiveTexturesForUsernameThatAlreadyProcessing
 }
 
 func (suite *QueueTestSuite) TestDoNothingWhenNoTasks() {
-	suite.Storage.On("Get", mock.Anything).Return(nil)
+	suite.Storage.On("GetUuid", "maksimkurb").Once().Return("", &ValueNotFound{})
-	// Storage.Set shouldn't be called
+	suite.Storage.On("StoreUuid", "maksimkurb", "").Once()
+	// Storage.GetTextures and Storage.StoreTextures shouldn't be called
 	suite.MojangApi.On("UsernameToUuids", []string{"maksimkurb"}).Once().Return([]*mojang.ProfileInfo{}, nil)
 
 	// Perform first iteration and await it finish
@@ -223,8 +294,8 @@ func (suite *QueueTestSuite) TestDoNothingWhenNoTasks() {
 }
 
 func (suite *QueueTestSuite) TestHandle429ResponseWhenExchangingUsernamesToUuids() {
-	suite.Storage.On("Get", mock.Anything).Return(nil)
+	suite.Storage.On("GetUuid", "maksimkurb").Once().Return("", &ValueNotFound{})
-	// Storage.Set shouldn't be called
+	// Storage.StoreUuid, Storage.GetTextures and Storage.StoreTextures shouldn't be called
 	suite.MojangApi.On("UsernameToUuids", []string{"maksimkurb"}).Once().Return(nil, &mojang.TooManyRequestsError{})
 
 	resultChan := suite.Queue.GetTexturesForUsername("maksimkurb")
@@ -235,8 +306,10 @@ func (suite *QueueTestSuite) TestHandle429ResponseWhenExchangingUsernamesToUuids
 }
 
 func (suite *QueueTestSuite) TestHandle429ResponseWhenRequestingUsersTextures() {
-	suite.Storage.On("Get", mock.Anything).Return(nil)
+	suite.Storage.On("GetUuid", "maksimkurb").Once().Return("", &ValueNotFound{})
-	// Storage.Set shouldn't be called
+	suite.Storage.On("StoreUuid", "maksimkurb", "0d252b7218b648bfb86c2ae476954d32").Once()
+	suite.Storage.On("GetTextures", "0d252b7218b648bfb86c2ae476954d32").Once().Return(nil, &ValueNotFound{})
+	// Storage.StoreTextures shouldn't be called
 	suite.MojangApi.On("UsernameToUuids", []string{"maksimkurb"}).Once().Return([]*mojang.ProfileInfo{
 		{Id: "0d252b7218b648bfb86c2ae476954d32", Name: "maksimkurb"},
 	}, nil)

api/mojang/queue/storage.go

@@ -2,18 +2,29 @@ package queue
 
 import "github.com/elyby/chrly/api/mojang"
 
+type UuidsStorage interface {
+	GetUuid(username string) (string, error)
+	StoreUuid(username string, uuid string)
+}
+
+type TexturesStorage interface {
+	// nil can be returned to indicate that there is no textures for uuid
+	// and we know about it. Return err only in case, when storage completely
+	// don't know anything about uuid
+	GetTextures(uuid string) (*mojang.SignedTexturesResponse, error)
+	StoreTextures(textures *mojang.SignedTexturesResponse)
+}
+
 type Storage interface {
-	Get(username string) *mojang.SignedTexturesResponse
+	UuidsStorage
-	Set(textures *mojang.SignedTexturesResponse)
+	TexturesStorage
 }
 
-// NilStorage used for testing purposes
+// This error can be used to indicate, that requested
-type NilStorage struct {
+// value doesn't exists in the storage
+type ValueNotFound struct {
 }
 
-func (*NilStorage) Get(username string) *mojang.SignedTexturesResponse {
+func (*ValueNotFound) Error() string {
-	return nil
+	return "value not found in storage"
-}
-
-func (*NilStorage) Set(textures *mojang.SignedTexturesResponse) {
 }