First local go service

api/internal/core/entities/Download.go

@@ -1,8 +0,0 @@
-package entities
-
-type Download struct {
-	ID     string `json:"id"`
-	Status string `json:"status"`
-	Link   string `json:"link"`
-	Data   string `json:"data"`
-}

api/internal/core/entities/download.go

@@ -0,0 +1,28 @@
+package entities
+
+import (
+	"downloader/pkg/common/uuid"
+	"errors"
+)
+
+type Download struct {
+	ID     string `json:"id"`
+	Status string `json:"status"`
+	Link   string `json:"link"`
+	Data   string `json:"data"`
+}
+
+func NewDownload(link string, data string) func(uuidGen uuid.Gen) (*Download, error) {
+	return func(uuidGen uuid.Gen) (*Download, error) {
+		if link == "" || data == "" {
+			return nil, errors.New("A field was not valid")
+		}
+
+		return &Download{
+			ID:     uuidGen.Create(),
+			Status: "scheduled",
+			Link:   link,
+			Data:   data,
+		}, nil
+	}
+}

api/internal/core/ports/download_request/download_request.go

@@ -3,11 +3,16 @@ package download_request
 import "downloader/internal/core/entities"
 
 type Service interface {
-	Schedule(provider string, link string) (entities.Download, error)
-	Get(id string) (entities.Download, error)
+	Schedule(provider string, link string) (*entities.Download, error)
+	Get(id string) (*entities.Download, error)
 }
 
 type Repository interface {
-	Create(download entities.Download) (entities.Download, error)
-	GetById(id string) (entities.Download, error)
+	Create(download *entities.Download) (*entities.Download, error)
+	GetById(id string) (*entities.Download, error)
+	Update(download *entities.Download) error
+}
+
+type BackgroundService interface {
+	Run(download *entities.Download) error
 }

api/internal/core/ports/download_request/in_memory.go

@@ -0,0 +1,110 @@
+package download_request
+
+import (
+	"downloader/internal/core/entities"
+	"downloader/pkg/common/uuid"
+	"errors"
+	"fmt"
+	"time"
+)
+
+// Repository
+type inMemoryRepository struct {
+	collection map[string]*entities.Download
+}
+
+func NewInMemoryRepository() Repository {
+	return &inMemoryRepository{collection: make(map[string]*entities.Download)}
+}
+
+func (i *inMemoryRepository) Create(download *entities.Download) (*entities.Download, error) {
+	if doc := i.collection[download.ID]; doc != nil {
+		return nil, errors.New("download request already exists")
+	}
+
+	i.collection[download.ID] = download
+
+	return download, nil
+}
+
+func (i *inMemoryRepository) Update(download *entities.Download) error {
+
+	if doc := i.collection[download.ID]; doc == nil {
+		return errors.New("download request doesn't exist exists")
+	}
+
+	i.collection[download.ID] = download
+
+	return nil
+}
+
+func (i *inMemoryRepository) GetById(id string) (*entities.Download, error) {
+	if download := i.collection[id]; download != nil {
+		return download, nil
+	} else {
+		return nil, errors.New("download was not found in the database")
+	}
+}
+
+// Service
+type localService struct {
+	repository        Repository
+	uuidGen           uuid.Gen
+	BackgroundService BackgroundService
+}
+
+func NewLocalService(repository Repository, uuidGen uuid.Gen, backgroundService BackgroundService) Service {
+	return &localService{
+		repository:        repository,
+		uuidGen:           uuidGen,
+		BackgroundService: backgroundService,
+	}
+}
+
+func (l *localService) Schedule(provider string, link string) (*entities.Download, error) {
+	download, err := entities.NewDownload(link, provider)(l.uuidGen)
+	if err != nil {
+		return nil, err
+	}
+
+	persistedDownloadRequest, uploadErr := l.repository.Create(download)
+	if uploadErr != nil {
+		return nil, uploadErr
+	}
+
+	err = l.BackgroundService.Run(persistedDownloadRequest)
+	if err != nil {
+		return nil, err
+	}
+
+	return persistedDownloadRequest, nil
+}
+
+func (l *localService) Get(id string) (*entities.Download, error) {
+	return l.repository.GetById(id)
+}
+
+// Background service
+type localBackgroundService struct {
+	repository Repository
+}
+
+func NewLocalBackgroundService(repository Repository) BackgroundService {
+	return &localBackgroundService{repository: repository}
+}
+
+func (l localBackgroundService) Run(download *entities.Download) error {
+	go func() {
+		time.Sleep(time.Second * 5)
+		download.Status = "done"
+		err := l.repository.Update(download)
+		if err != nil {
+			fmt.Printf("Download request: %s failed\n", download.ID)
+			panic(err)
+		} else {
+			fmt.Printf("Download request: %s done\n", download.ID)
+		}
+	}()
+
+	return nil
+}