Add function for path conversion with fallback

src/util/paths.rs

@@ -1,4 +1,5 @@
 /// Generates random paths for storing assets
+use log::*;
 use rand::{rng, Rng};
 use std::ffi::OsStr;
 use std::path::{Path, PathBuf};
@@ -103,3 +104,15 @@ pub fn to_web_path<P: AsRef<Path>>(path: P, asset_type: AssetType) -> BackendRes
 
     Ok(url_path.path().to_string())
 }
+
+/// Convert a server-side image path to a web path,
+/// or fall back to a placeholder if it fails or the `path` is `None`,
+/// If path conversion fails, the error is logged as a "warning".
+pub fn to_web_path_or_placeholder<P: AsRef<Path>>(path: Option<P>) -> String {
+    path.and_then(|path| {
+        to_web_path(path, AssetType::Image)
+            .inspect_err(|e| warn!("{e}"))
+            .ok()
+    })
+    .unwrap_or(MUSIC_PLACEHOLDER_WEB_PATH.to_string())
+}