From 2e63a6cfc48469015464fa5c41c6c47b0b736903 Mon Sep 17 00:00:00 2001
From: Alexeyzem <Alex.zem2015@mail.ru>
Date: Wed, 18 Dec 2024 15:02:32 +0300
Subject: [PATCH] detect type with http.Detected

---
 internal/fileService/controller/controller.go | 35 ++++++++++++++-----
 internal/fileService/controller/mock.go       |  6 ++--
 internal/fileService/service/fileService.go   |  5 ++-
 3 files changed, 32 insertions(+), 14 deletions(-)

diff --git a/internal/fileService/controller/controller.go b/internal/fileService/controller/controller.go
index 0e551121..ab5baebc 100644
--- a/internal/fileService/controller/controller.go
+++ b/internal/fileService/controller/controller.go
@@ -1,9 +1,11 @@
 package controller
 
 import (
+	"bytes"
 	"context"
 	"errors"
 	"fmt"
+	"io"
 	"mime/multipart"
 	"net/http"
 	"strings"
@@ -26,8 +28,8 @@ var fileFormat = map[string]struct{}{
 //go:generate mockgen -destination=mock.go -source=$GOFILE -package=${GOPACKAGE}
 type fileService interface {
 	Upload(ctx context.Context, name string) ([]byte, error)
-	Download(ctx context.Context, file multipart.File, format string) (string, error)
-	DownloadNonImage(ctx context.Context, file multipart.File, format, realName string) (string, error)
+	Download(ctx context.Context, file io.Reader, format string) (string, error)
+	DownloadNonImage(ctx context.Context, file io.Reader, format, realName string) (string, error)
 	UploadNonImage(ctx context.Context, name string) ([]byte, error)
 }
 
@@ -51,6 +53,17 @@ func NewFileController(fileService fileService, responder responder) *FileContro
 	}
 }
 
+func getFormat(buf []byte) string {
+	formats := http.DetectContentType(buf)
+	format := strings.Split(formats, "/")[1]
+
+	if strings.HasPrefix(format, "plain") {
+		format = "txt"
+	}
+
+	return format
+}
+
 func sanitize(input string) string {
 	sanitizer := bluemonday.UGCPolicy()
 	cleaned := sanitizer.Sanitize(input)
@@ -138,23 +151,29 @@ func (fc *FileController) Download(w http.ResponseWriter, r *http.Request) {
 		}
 	}(file)
 
-	formats := strings.Split(header.Header.Get("Content-Type"), "/")
-	if len(formats) != 2 {
-		fc.responder.ErrorBadRequest(w, my_err.ErrWrongFiletype, reqID)
+	buf := bytes.NewBuffer(make([]byte, 20))
+	n, err := file.Read(buf.Bytes())
+	if err != nil {
+		fc.responder.ErrorBadRequest(w, err, reqID)
 		return
 	}
+	format := getFormat(buf.Bytes()[:n])
+
+	_, err = io.Copy(buf, file)
+	if err != nil {
+		fc.responder.ErrorBadRequest(w, err, reqID)
+	}
 	var url string
-	format := formats[1]
 
 	if _, ok := fileFormat[format]; ok {
-		url, err = fc.fileService.Download(r.Context(), file, format)
+		url, err = fc.fileService.Download(r.Context(), buf, format)
 	} else {
 		name := header.Filename
 		if len(name+format) > 55 {
 			fc.responder.ErrorBadRequest(w, errors.New("file name is too big"), reqID)
 			return
 		}
-		url, err = fc.fileService.DownloadNonImage(r.Context(), file, format, name)
+		url, err = fc.fileService.DownloadNonImage(r.Context(), buf, format, name)
 	}
 
 	if err != nil {
diff --git a/internal/fileService/controller/mock.go b/internal/fileService/controller/mock.go
index 816a55a1..76b8237e 100644
--- a/internal/fileService/controller/mock.go
+++ b/internal/fileService/controller/mock.go
@@ -11,7 +11,7 @@ package controller
 
 import (
 	context "context"
-	multipart "mime/multipart"
+	io "io"
 	http "net/http"
 	reflect "reflect"
 
@@ -43,7 +43,7 @@ func (m *MockfileService) EXPECT() *MockfileServiceMockRecorder {
 }
 
 // Download mocks base method.
-func (m *MockfileService) Download(ctx context.Context, file multipart.File, format string) (string, error) {
+func (m *MockfileService) Download(ctx context.Context, file io.Reader, format string) (string, error) {
 	m.ctrl.T.Helper()
 	ret := m.ctrl.Call(m, "Download", ctx, file, format)
 	ret0, _ := ret[0].(string)
@@ -58,7 +58,7 @@ func (mr *MockfileServiceMockRecorder) Download(ctx, file, format any) *gomock.C
 }
 
 // DownloadNonImage mocks base method.
-func (m *MockfileService) DownloadNonImage(ctx context.Context, file multipart.File, format, realName string) (string, error) {
+func (m *MockfileService) DownloadNonImage(ctx context.Context, file io.Reader, format, realName string) (string, error) {
 	m.ctrl.T.Helper()
 	ret := m.ctrl.Call(m, "DownloadNonImage", ctx, file, format, realName)
 	ret0, _ := ret[0].(string)
diff --git a/internal/fileService/service/fileService.go b/internal/fileService/service/fileService.go
index b2eb0cc3..fab9845c 100644
--- a/internal/fileService/service/fileService.go
+++ b/internal/fileService/service/fileService.go
@@ -4,7 +4,6 @@ import (
 	"context"
 	"fmt"
 	"io"
-	"mime/multipart"
 	"os"
 
 	"github.com/google/uuid"
@@ -16,7 +15,7 @@ func NewFileService() *FileService {
 	return &FileService{}
 }
 
-func (f *FileService) Download(ctx context.Context, file multipart.File, format string) (string, error) {
+func (f *FileService) Download(ctx context.Context, file io.Reader, format string) (string, error) {
 	var (
 		fileName = uuid.New().String()
 		filePath = fmt.Sprintf("/image/%s.%s", fileName, format)
@@ -38,7 +37,7 @@ func (f *FileService) Download(ctx context.Context, file multipart.File, format
 }
 
 func (f *FileService) DownloadNonImage(
-	ctx context.Context, file multipart.File, format, realName string,
+	ctx context.Context, file io.Reader, format, realName string,
 ) (string, error) {
 	var (
 		fileName = uuid.New().String()