From 2c1ab04cc72396f29d938734ce0a86e393ee4552 Mon Sep 17 00:00:00 2001
From: Niclas Overby <niclas@overby.me>
Date: Fri, 6 Mar 2026 14:25:24 +0100
Subject: [PATCH] appview,knotserver,camo: add AVIF and modern image format
 support

Add support for AVIF, JPEG XL, and HEIF image formats across the stack:

- knotserver/xrpc: override MIME types for formats that Go's
  http.DetectContentType does not recognize (.avif, .jxl, .heic, .heif),
  using a switch statement like the existing .svg override
- camo: add image/avif, image/heif, and image/jxl to the allowed MIME
  types list
- appview/repo: add .avif, .jxl, .heic, .heif to the image extension
  list in the blob viewer

Without these changes, AVIF files (and other modern formats) are rejected
by the knot server with a 403 (detected as application/octet-stream),
blocked by the camo proxy with a 415, and not previewed in the blob viewer.

Signed-off-by: Niclas Overby <niclas@overby.me>
---
 appview/repo/blob.go         |  2 +-
 camo/src/mimetypes.json      |  3 +++
 knotserver/xrpc/repo_blob.go | 10 +++++++++-
 3 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/appview/repo/blob.go b/appview/repo/blob.go
index b5f3f3b4..c7fd680c 100644
--- a/appview/repo/blob.go
+++ b/appview/repo/blob.go
@@ -236,7 +236,7 @@ func NewBlobView(resp *tangled.RepoBlob_Output, config *config.Config, repo *mod
 		ext := strings.ToLower(filepath.Ext(resp.Path))
 
 		switch ext {
-		case ".jpg", ".jpeg", ".png", ".gif", ".webp":
+		case ".jpg", ".jpeg", ".png", ".gif", ".webp", ".avif", ".jxl", ".heic", ".heif":
 			view.ContentType = models.BlobContentTypeImage
 			view.HasRawView = true
 			view.HasRenderedView = true
diff --git a/camo/src/mimetypes.json b/camo/src/mimetypes.json
index f9e04653..46f106b5 100644
--- a/camo/src/mimetypes.json
+++ b/camo/src/mimetypes.json
@@ -1,10 +1,13 @@
 [
+  "image/avif",
   "image/bmp",
   "image/cgm",
   "image/g3fax",
   "image/gif",
+  "image/heif",
   "image/ief",
   "image/jp2",
+  "image/jxl",
   "image/jpeg",
   "image/jpg",
   "image/pict",
diff --git a/knotserver/xrpc/repo_blob.go b/knotserver/xrpc/repo_blob.go
index c8add0c7..91570348 100644
--- a/knotserver/xrpc/repo_blob.go
+++ b/knotserver/xrpc/repo_blob.go
@@ -74,8 +74,16 @@ func (x *Xrpc) RepoBlob(w http.ResponseWriter, r *http.Request) {
 
 	mimeType := http.DetectContentType(contents)
 
-	if filepath.Ext(treePath) == ".svg" {
+	// override MIME types for formats that http.DetectContentType does not recognize
+	switch filepath.Ext(treePath) {
+	case ".svg":
 		mimeType = "image/svg+xml"
+	case ".avif":
+		mimeType = "image/avif"
+	case ".jxl":
+		mimeType = "image/jxl"
+	case ".heic", ".heif":
+		mimeType = "image/heif"
 	}
 
 	if raw {
-- 
2.51.2