Add Image Diff for SVG files (#14867)

* Added type sniffer.

* Switched content detection from base to typesniffer.

* Added GuessContentType to Blob.

* Moved image info logic to client.
Added support for SVG images in diff.

* Restore old blocked svg behaviour.

* Added missing image formats.

* Execute image diff only when container is visible.

* add margin to spinner

* improve BIN tag on image diffs

* Default to render view.

* Show image diff on incomplete diff.

Co-authored-by: silverwind <me@silverwind.io>
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>
Co-authored-by: Lauris BH <lauris@nix.lv>

1 files changed, 13 insertions, 0 deletions

diff --git a/modules/git/blob.go b/modules/git/blob.go
index 674a6a9592..732356e5b2 100644
--- a/modules/git/blob.go
+++ b/modules/git/blob.go
@@ -10,6 +10,8 @@ import (
 	"encoding/base64"
 	"io"
 	"io/ioutil"
+
+	"code.gitea.io/gitea/modules/typesniffer"
 )
 
 // This file contains common functions between the gogit and !gogit variants for git Blobs
@@ -82,3 +84,14 @@ func (b *Blob) GetBlobContentBase64() (string, error) {
 	}
 	return string(out), nil
 }
+
+// GuessContentType guesses the content type of the blob.
+func (b *Blob) GuessContentType() (typesniffer.SniffedType, error) {
+	r, err := b.DataAsync()
+	if err != nil {
+		return typesniffer.SniffedType{}, err
+	}
+	defer r.Close()
+
+	return typesniffer.DetectContentTypeFromReader(r)
+}