Switch to https://github.com/h2non/filetype

This library is much better at detecting MIME types properly than the
existing one. Fixes #117.

meta.go

@@ -15,8 +15,8 @@ import (
 	"time"
 	"unicode"
 
-	"bitbucket.org/taruti/mimemagic"
 	"github.com/dchest/uniuri"
+	"gopkg.in/h2non/filetype.v1"
 )
 
 type MetadataJSON struct {
@@ -66,7 +66,12 @@ func generateMetadata(fName string, exp time.Time, delKey string) (m Metadata, e
 	header := make([]byte, 512)
 	file.Read(header)
 
-	m.Mimetype = mimemagic.Match("", header)
+	kind, err := filetype.Match(header)
+	if err != nil {
+		m.Mimetype = "application/octet-stream"
+	} else {
+		m.Mimetype = kind.MIME.Value
+	}
 
 	if m.Mimetype == "" {
 		// Check if the file seems anything like text

upload.go

@@ -15,9 +15,9 @@ import (
 	"strings"
 	"time"
 
-	"bitbucket.org/taruti/mimemagic"
 	"github.com/dchest/uniuri"
 	"github.com/zenazn/goji/web"
+	"gopkg.in/h2non/filetype.v1"
 )
 
 var fileBlacklist = map[string]bool{
@@ -218,15 +218,12 @@ func processUpload(upReq UploadRequest) (upload Upload, err error) {
 		header = header[:n]
 
 		// Determine the type of file from header
-		mimetype := mimemagic.Match("", header)
-
-		// If the mime type is in our map, use that
-		// otherwise just use "ext"
-		if val, exists := mimeToExtension[mimetype]; exists {
-			extension = val
-		} else {
+		kind, err := filetype.Match(header)
+		if err != nil {
 			extension = "ext"
 		}
+
+		extension = kind.Extension
 	}
 
 	upload.Filename = strings.Join([]string{barename, extension}, ".")