First local go service

api/.idea/.gitignore

@@ -0,0 +1,8 @@
+# Default ignored files
+/shelf/
+/workspace.xml
+# Editor-based HTTP Client requests
+/httpRequests/
+# Datasource local storage ignored files
+/dataSources/
+/dataSources.local.xml

api/.idea/api.iml

@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="WEB_MODULE" version="4">
+  <component name="Go" enabled="true" />
+  <component name="NewModuleRootManager">
+    <content url="file://$MODULE_DIR$" />
+    <orderEntry type="inheritedJdk" />
+    <orderEntry type="sourceFolder" forTests="false" />
+  </component>
+</module>

api/.idea/modules.xml

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ProjectModuleManager">
+    <modules>
+      <module fileurl="file://$PROJECT_DIR$/.idea/api.iml" filepath="$PROJECT_DIR$/.idea/api.iml" />
+    </modules>
+  </component>
+</project>

api/.idea/vcs.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="VcsDirectoryMappings">
+    <mapping directory="$PROJECT_DIR$/.." vcs="Git" />
+  </component>
+</project>

api/go.mod

@@ -5,4 +5,5 @@ go 1.17
 require (
 	github.com/go-chi/chi v1.5.4 // indirect
 	github.com/go-chi/render v1.0.1 // indirect
+	github.com/google/uuid v1.3.0 // indirect
 )

api/go.sum

@@ -2,3 +2,5 @@ github.com/go-chi/chi v1.5.4 h1:QHdzF2szwjqVV4wmByUnTcsbIg7UGaQ0tPF2t5GcAIs=
 github.com/go-chi/chi v1.5.4/go.mod h1:uaf8YgoFazUOkPBG7fxPftUylNumIev9awIWOENIuEg=
 github.com/go-chi/render v1.0.1 h1:4/5tis2cKaNdnv9zFLfXzcquC9HbeZgCnxGnKrltBS8=
 github.com/go-chi/render v1.0.1/go.mod h1:pq4Rr7HbnsdaeHagklXub+p6Wd16Af5l9koip1OvJns=
+github.com/google/uuid v1.3.0 h1:t6JiXgmwXMjEs8VusXIJk2BXHsn+wx8BZdTaoZ5fu7I=
+github.com/google/uuid v1.3.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=

api/internal/app/api/common/responses/responses.go

@@ -27,3 +27,7 @@ func ErrInvalidRequest(err error) render.Renderer {
 		ErrorText:      err.Error(),
 	}
 }
+
+func ErrNotFound() render.Renderer {
+	return &ErrResponse{HTTPStatusCode: 404, StatusText: "Resource not found."}
+}

api/internal/app/api/download/download.go

@@ -1,42 +0,0 @@
-package download
-
-import (
-	"downloader/internal/app/api/common/responses"
-	"errors"
-	"github.com/go-chi/chi"
-	"github.com/go-chi/render"
-	"net/http"
-)
-
-type api struct{}
-
-func New() *api {
-	return &api{}
-}
-
-func (api *api) SetupDownloadApi(router *chi.Mux) {
-	router.Route("/downloads", func(r chi.Router) {
-		r.Post("/", api.requestDownload)
-	})
-}
-
-type requestDownloadRequest struct {
-	Provider string `json:"provider"`
-	Link     string `json:"link"`
-}
-
-func (dr *requestDownloadRequest) Bind(r *http.Request) error {
-	if dr.Link == "" || dr.Provider == "" {
-		return errors.New("missing required download request field")
-	}
-
-	return nil
-}
-
-func (api *api) requestDownload(w http.ResponseWriter, r *http.Request) {
-	data := &requestDownloadRequest{}
-	if err := render.Bind(r, data); err != nil {
-		_ = render.Render(w, r, responses.ErrInvalidRequest(err))
-		return
-	}
-}

api/internal/app/api/download/download_context.go

@@ -0,0 +1,22 @@
+package download
+
+import (
+	"context"
+	"downloader/internal/app/api/common/responses"
+	"github.com/go-chi/chi"
+	"github.com/go-chi/render"
+	"net/http"
+)
+
+func Context(next http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if downloadId := chi.URLParam(r, "downloadId"); downloadId != "" {
+			ctx := context.WithValue(r.Context(), "downloadId", downloadId)
+			next.ServeHTTP(w, r.WithContext(ctx))
+		} else {
+			_ = render.Render(w, r, responses.ErrNotFound())
+			return
+		}
+
+	})
+}

api/internal/app/api/download/request_download.go

@@ -0,0 +1,66 @@
+package download
+
+import (
+	"downloader/internal/app/api/common/responses"
+	"downloader/internal/core/entities"
+	"errors"
+	"github.com/go-chi/render"
+	"net/http"
+)
+
+type requestDownloadRequest struct {
+	Provider string `json:"provider"`
+	Link     string `json:"link"`
+}
+
+type requestDownloadResponse struct {
+	*entities.Download
+}
+
+func (_ requestDownloadResponse) Render(_ http.ResponseWriter, _ *http.Request) error {
+	return nil
+}
+
+func (dr *requestDownloadRequest) Bind(r *http.Request) error {
+	if dr.Link == "" || dr.Provider == "" {
+		return errors.New("missing required download request field")
+	}
+
+	return nil
+}
+
+func (a *api) requestDownload(w http.ResponseWriter, r *http.Request) {
+	data := &requestDownloadRequest{}
+	if err := render.Bind(r, data); err != nil {
+		_ = render.Render(w, r, responses.ErrInvalidRequest(err))
+		return
+	}
+
+	download, err := a.drService.Schedule(data.Provider, data.Link)
+	if err != nil {
+		_ = render.Render(w, r, responses.ErrInvalidRequest(err))
+		return
+	}
+
+	render.Status(r, http.StatusAccepted)
+	_ = render.Render(w, r, newRequestDownloadResponse(download))
+}
+
+func (a *api) getDownloadById(w http.ResponseWriter, r *http.Request) {
+	downloadId := r.Context().Value("downloadId").(string)
+
+	download, err := a.drService.Get(downloadId)
+	if err != nil {
+		_ = render.Render(w, r, responses.ErrNotFound())
+		return
+	}
+
+	if err := render.Render(w, r, newRequestDownloadResponse(download)); err != nil {
+		_ = render.Render(w, r, responses.ErrInvalidRequest(err))
+		return
+	}
+}
+
+func newRequestDownloadResponse(download *entities.Download) *requestDownloadResponse {
+	return &requestDownloadResponse{Download: download}
+}

api/internal/app/api/download/routes.go

@@ -0,0 +1,24 @@
+package download
+
+import (
+	"downloader/internal/core/ports/download_request"
+	"github.com/go-chi/chi"
+)
+
+type api struct {
+	drService download_request.Service
+}
+
+func New(service download_request.Service) *api {
+	return &api{drService: service}
+}
+
+func (a *api) SetupDownloadApi(router *chi.Mux) {
+	router.Route("/downloads", func(r chi.Router) {
+		r.Post("/", a.requestDownload)
+		r.Route("/{downloadId}", func(r chi.Router) {
+			r.Use(Context)
+			r.Get("/", a.getDownloadById)
+		})
+	})
+}

api/internal/app/router/router.go

@@ -2,6 +2,8 @@ package router
 
 import (
 	"downloader/internal/app/api/download"
+	"downloader/internal/core/ports/download_request"
+	"downloader/pkg/common/uuid"
 	"github.com/go-chi/chi"
 	"github.com/go-chi/chi/middleware"
 	"net/http"
@@ -23,7 +25,7 @@ func NewRouter() *router {
 }
 
 func (router *router) Run() {
-	http.ListenAndServe(":3333", router.internalRouter)
+	_ = http.ListenAndServe(":3333", router.internalRouter)
 }
 
 func (router *router) RegisterApi() *chi.Mux {
@@ -41,9 +43,17 @@ func (router *router) setupMiddleware() *router {
 }
 
 func (router *router) setupRoutes() *router {
-	downloadApi := download.New()
+	setupDownloadRoute(router)
-
-	downloadApi.SetupDownloadApi(router.internalRouter)
 
 	return router
 }
+
+func setupDownloadRoute(router *router) {
+	drRepository := download_request.NewInMemoryRepository()
+	drBackgroundService := download_request.NewLocalBackgroundService(drRepository)
+	gen := uuid.New()
+
+	drService := download_request.NewLocalService(drRepository, gen, drBackgroundService)
+	downloadApi := download.New(drService)
+	downloadApi.SetupDownloadApi(router.internalRouter)
+}

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)
+	Schedule(provider string, link string) (*entities.Download, error)
-	Get(id string) (entities.Download, error)
+	Get(id string) (*entities.Download, error)
 }
 
 type Repository interface {
-	Create(download entities.Download) (entities.Download, error)
+	Create(download *entities.Download) (*entities.Download, error)
-	GetById(id string) (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
+}

api/pkg/common/uuid/uuid.go

@@ -0,0 +1,18 @@
+package uuid
+
+import "github.com/google/uuid"
+
+type Gen interface {
+	Create() string
+}
+
+type uuidGen struct {
+}
+
+func New() *uuidGen {
+	return &uuidGen{}
+}
+
+func (u uuidGen) Create() string {
+	return uuid.New().String()
+}