Simplify file serving from local or remote.

Prior, we would decide how to serve a file based on whether it was local
or remote at a router level. This moves everything to an io.Copy call in
the router with the Provider returning an io.Reader.

files/backblaze.go

@@ -7,7 +7,9 @@ import (
 	"fmt"
 	"io"
 	"io/ioutil"
+	"mime"
 	"net/http"
+	"path/filepath"
 	"strings"
 )
 
@@ -142,7 +144,7 @@ func (bp *BackblazeProvider) FilePath(path string) string {
 	return ""
 }
 
-func (bp *BackblazeProvider) RemoteFile(path string, w io.Writer) {
+func (bp *BackblazeProvider) SendFile(path string, w io.Writer) (stream io.Reader, contenttype string, err error) {
 	client := &http.Client{}
 	// Get bucket name >:(
 	bucketIdPayload := fmt.Sprintf(`{"accountId": "%s", "bucketId": "%s"}`, bp.Name, bp.Bucket)
@@ -150,20 +152,17 @@ func (bp *BackblazeProvider) RemoteFile(path string, w io.Writer) {
 	req, err := http.NewRequest("POST", bp.Location + "/b2api/v2/b2_list_buckets",
 		bytes.NewBuffer([]byte(bucketIdPayload)))
 	if err != nil {
-		fmt.Println(err.Error())
-		return
+		return nil, contenttype, err
 	}
 	req.Header.Add("Authorization", bp.Authentication)
 
 	res, err := client.Do(req)
 	if err != nil {
-		fmt.Println(err.Error())
-		return
+		return nil, contenttype, err
 	}
 	bucketData, err := ioutil.ReadAll(res.Body)
 	if err != nil {
-		fmt.Println(err.Error())
-		return
+		return nil, contenttype, err
 	}
 
 	var data BackblazeBucketInfoPayload
@@ -175,22 +174,23 @@ func (bp *BackblazeProvider) RemoteFile(path string, w io.Writer) {
 		url,
 		bytes.NewBuffer([]byte("")))
 	if err != nil {
-		fmt.Println(err.Error())
-		return
+		return nil, contenttype, err
 	}
 	req.Header.Add("Authorization", bp.Authentication)
 	file, err := client.Do(req)
 
 	if err != nil {
-		fmt.Println(err.Error())
-		return
+		return nil, contenttype, err
 	}
 
-	_, err = io.Copy(w, file.Body)
-	if err != nil {
-		fmt.Println(err.Error())
-		return
+	contenttype = mime.TypeByExtension(filepath.Ext(path))
+	if contenttype == "" {
+		var buf [512]byte
+		n, _ := io.ReadFull(file.Body, buf[:])
+		contenttype = http.DetectContentType(buf[:n])
 	}
+
+	return file.Body, contenttype, err
 }
 
 func (bp *BackblazeProvider) SaveFile(file io.Reader, filename string, path string) bool {

files/disk.go

@@ -4,7 +4,10 @@ import (
 	"fmt"
 	"io"
 	"io/ioutil"
+	"mime"
+	"net/http"
 	"os"
+	"path/filepath"
 	"strings"
 )
 
@@ -42,13 +45,22 @@ func (dp *DiskProvider) GetDirectory(path string) Directory {
 	}
 }
 
-func (dp *DiskProvider) FilePath(path string) string {
+func (dp *DiskProvider) SendFile(path string, writer io.Writer) (stream io.Reader, contenttype string, err error) {
 	rp := strings.Join([]string{dp.Location,path}, "/")
-	return rp
-}
+	f, err := os.Open(rp)
+	if err != nil {
+		return stream, contenttype, err
+	}
 
-func (dp *DiskProvider) RemoteFile(path string, writer io.Writer) {
-	return
+	contenttype = mime.TypeByExtension(filepath.Ext(rp))
+
+	if contenttype == "" {
+		var buf [512]byte
+		n, _ := io.ReadFull(f, buf[:])
+		contenttype = http.DetectContentType(buf[:n])
+	}
+
+	return f, contenttype, nil
 }
 
 func (dp *DiskProvider) SaveFile(file io.Reader, filename string, path string) bool {

files/fileprovider.go

@@ -39,7 +39,7 @@ type FileProviderInterface interface {
 	Setup(args map[string]string) (ok bool)
 	GetDirectory(path string) (directory Directory)
 	FilePath(path string) (realpath string)
-	RemoteFile(path string, writer io.Writer)
+	SendFile(path string, writer io.Writer) (stream io.Reader, contenttype string, err error)
 	SaveFile(file io.Reader, filename string, path string) (ok bool)
 	ObjectInfo(path string) (exists bool, isDir bool, location string)
 	CreateDirectory(path string) (ok bool)
@@ -64,7 +64,7 @@ func (f FileProvider) FilePath(path string) string {
 }
 
 // RemoteFile will bypass http.ServeContent() and instead write directly to the response.
-func (f FileProvider) RemoteFile(path string, writer io.Writer) {
+func (f FileProvider) SendFile(path string, writer io.Writer) (stream io.Reader, contenttype string, err error) {
 	return
 }
 

router/filerouter.go

@@ -3,14 +3,14 @@ package router
 import (
 	"encoding/json"
 	"fmt"
-	"github.com/gmemstr/nas/files"
-	"github.com/gorilla/mux"
+	"io"
 	"net/http"
 	"net/url"
-	"os"
 	"sort"
 	"strings"
-	"time"
+
+	"github.com/gmemstr/nas/files"
+	"github.com/gorilla/mux"
 )
 
 func handleProvider() handler {
@@ -29,7 +29,7 @@ func handleProvider() handler {
 					StatusCode: http.StatusInternalServerError,
 				}
 			}
-			ok, isDir, location := provider.ObjectInfo(filename)
+			ok, isDir, _ := provider.ObjectInfo(filename)
 			if !ok {
 				return &httpError{
 					Message:    fmt.Sprintf("error locating file %s\n", filename),
@@ -49,27 +49,25 @@ func handleProvider() handler {
 				}
 				w.Write(data)
 				return nil
-			}
+			} else {
+				stream, contenttype, err := provider.SendFile(filename, w)
 
-			// If the file is local, attempt to use http.ServeContent for correct headers.
-			if location == files.FileIsLocal {
-				rp := provider.FilePath(filename)
-				if rp != "" {
-					f, err := os.Open(rp)
-					if err != nil {
-						return &httpError{
-							Message:    fmt.Sprintf("error opening file %s\n", rp),
-							StatusCode: http.StatusInternalServerError,
-						}
+				if err != nil {
+					return &httpError{
+						Message:    fmt.Sprintf("error finding file %s\n", vars["file"]),
+						StatusCode: http.StatusNotFound,
+					}
+				}
+				w.Header().Set("Content-Type", contenttype)
+				_, err = io.Copy(w, stream)
+				if err != nil {
+					return &httpError{
+						Message:    fmt.Sprintf("unable to write %s\n", vars["file"]),
+						StatusCode: http.StatusBadGateway,
 					}
-					http.ServeContent(w, r, filename, time.Time{}, f)
 				}
 			}
-			// If the file is remote, then delegate the writing to the response to the provider.
-			// This isn't a great workaround, but avoids caching the whole file in mem or on disk.
-			if location == files.FileIsRemote {
-				provider.RemoteFile(filename, w)
-			}
+
 			return nil
 		}