Detect proper avatar type to return instead of returning image/*

backend/go.mod

@@ -11,7 +11,7 @@ require (
 	github.com/go-chi/chi/v5 v5.1.0
 	github.com/go-chi/cors v1.2.1
 	github.com/go-chi/render v1.0.3
-	github.com/go-pkgz/auth v1.24.1
+	github.com/go-pkgz/auth v1.24.2
 	github.com/go-pkgz/jrpc v0.3.0
 	github.com/go-pkgz/lcw/v2 v2.0.0
 	github.com/go-pkgz/lgr v0.11.1

backend/go.sum

@@ -66,6 +66,10 @@ github.com/go-pkgz/auth v1.24.1-0.20240919232608-9e446b888187 h1:1oHLySWdk0HfDIF
 github.com/go-pkgz/auth v1.24.1-0.20240919232608-9e446b888187/go.mod h1:xmnzq6g8mhemW1nHnkuByXkBXsHrNf9/qkiVwJugWIs=
 github.com/go-pkgz/auth v1.24.1 h1:izSFGxwNEZ2MujKJWXddKc+lUW+kVP02JBXouQIW8b4=
 github.com/go-pkgz/auth v1.24.1/go.mod h1:xmnzq6g8mhemW1nHnkuByXkBXsHrNf9/qkiVwJugWIs=
+github.com/go-pkgz/auth v1.24.2-0.20240921022538-30916c085e04 h1:DZzcdFb/EzXjQex8lDq/NqubVqwCXeyGxU5swYEVAYk=
+github.com/go-pkgz/auth v1.24.2-0.20240921022538-30916c085e04/go.mod h1:xmnzq6g8mhemW1nHnkuByXkBXsHrNf9/qkiVwJugWIs=
+github.com/go-pkgz/auth v1.24.2 h1:imMjUvTM0c8iOvP/GNGcuNcB/7gF3jFTF9dIPzlAOqI=
+github.com/go-pkgz/auth v1.24.2/go.mod h1:xmnzq6g8mhemW1nHnkuByXkBXsHrNf9/qkiVwJugWIs=
 github.com/go-pkgz/email v0.5.0 h1:fdtMDGJ8NwyBACLR0LYHaCIK/OeUwZHMhH7Q0+oty9U=
 github.com/go-pkgz/email v0.5.0/go.mod h1:BdxglsQnymzhfdbnncEE72a6DrucZHy6I+42LK2jLEc=
 github.com/go-pkgz/expirable-cache v0.1.0/go.mod h1:GTrEl0X+q0mPNqN6dtcQXksACnzCBQ5k/k1SwXJsZKs=

backend/vendor/github.com/go-pkgz/auth/avatar/avatar.go

@@ -23,6 +23,9 @@ import (
 	"github.com/go-pkgz/auth/token"
 )
 
+// http.sniffLen is 512 bytes which is how much we need to read to detect content type
+const sniffLen = 512
+
 // Proxy provides http handler for avatars from avatar.Store
 // On user login token will call Put and it will retrieve and save picture locally.
 type Proxy struct {
@@ -100,7 +103,6 @@ func (p *Proxy) load(url string, client *http.Client) (rc io.ReadCloser, err err
 
 // Handler returns token routes for given provider
 func (p *Proxy) Handler(w http.ResponseWriter, r *http.Request) {
-
 	if r.Method != "GET" {
 		w.WriteHeader(http.StatusMethodNotAllowed)
 	}
@@ -136,9 +138,25 @@ func (p *Proxy) Handler(w http.ResponseWriter, r *http.Request) {
 		}
 	}()
 
-	w.Header().Set("Content-Type", "image/*")
+	buf := make([]byte, sniffLen)
+	n, err := avReader.Read(buf)
+	if err != nil && err != io.EOF {
+		p.Logf("[WARN] can't read from avatar reader for %s, %s", avatarID, err)
+		rest.SendErrorJSON(w, r, p.L, http.StatusInternalServerError, err, "can't read avatar")
+		return
+	}
 	w.Header().Set("Content-Length", strconv.Itoa(size))
+	contentType := http.DetectContentType(buf)
+	if contentType == "application/octet-stream" {
+		contentType = "image/*"
+	}
+	w.Header().Set("Content-Type", contentType)
 	w.WriteHeader(http.StatusOK)
+	if _, err = w.Write(buf[:n]); err != nil {
+		p.Logf("[WARN] can't write response to %s, %s", r.RemoteAddr, err)
+		return
+	}
+	// write the rest of response size if it's bigger than 512 bytes, or nothing as EOF would be sent right away then
 	if _, err = io.Copy(w, avReader); err != nil {
 		p.Logf("[WARN] can't send response to %s, %s", r.RemoteAddr, err)
 	}

backend/vendor/modules.txt

@@ -65,7 +65,7 @@ github.com/go-chi/render
 github.com/go-oauth2/oauth2/v4
 github.com/go-oauth2/oauth2/v4/errors
 github.com/go-oauth2/oauth2/v4/server
-# github.com/go-pkgz/auth v1.24.1
+# github.com/go-pkgz/auth v1.24.2
 ## explicit; go 1.21
 github.com/go-pkgz/auth
 github.com/go-pkgz/auth/avatar