fix(media): return an error when content is failed to be parsed as an image

src/api/client_server/media.rs

@@ -348,9 +348,9 @@ async fn get_content_thumbnail(
 ) -> Result<get_content_thumbnail::v1::Response, Error> {
     let mxc = format!("mxc://{}/{}", server_name, media_id);
 
-    if let Ok(Some(FileMeta {
+    if let Some(FileMeta {
         file, content_type, ..
-    })) = services()
+    }) = services()
         .media
         .get_thumbnail(
             mxc.clone(),
@@ -361,7 +361,7 @@ async fn get_content_thumbnail(
                 .try_into()
                 .map_err(|_| Error::BadRequest(ErrorKind::InvalidParam, "Height is invalid."))?,
         )
-        .await
+        .await?
     {
         Ok(get_content_thumbnail::v1::Response { file, content_type })
     } else if server_name != services().globals.server_name() && allow_remote {

src/service/media/mod.rs

@@ -2,7 +2,10 @@ mod data;
 use std::io::Cursor;
 
 pub use data::Data;
-use ruma::http_headers::{ContentDisposition, ContentDispositionType};
+use ruma::{
+    api::client::error::ErrorKind,
+    http_headers::{ContentDisposition, ContentDispositionType},
+};
 
 use crate::{services, Result};
 use image::imageops::FilterType;
@@ -219,12 +222,11 @@ impl Service {
                     file: thumbnail_bytes.to_vec(),
                 }))
             } else {
-                // Couldn't parse file to generate thumbnail, send original
-                Ok(Some(FileMeta {
-                    content_disposition,
-                    content_type,
-                    file: file.to_vec(),
-                }))
+                // Couldn't parse file to generate thumbnail, likely not an image
+                return Err(crate::Error::BadRequest(
+                ErrorKind::Unknown,
+                "Unable to generate thumbnail for the requested content (likely is not an image)",
+            ));
             }
         } else {
             Ok(None)