fix(settings): allow UCI reflector file loading to be disabled

README.md

@@ -57,3 +57,22 @@ You can also build an OpenWrt package to install in your images with the SDK:
    # Copy the generated .ipk from bin/packages/... to your router
    opkg install sqm-autorate-rust_*.ipk
    ```
+
+## Reflector files and inline UCI reflectors
+
+Inline `config reflector` sections supplement the default
+`/etc/sqm-autorate-rust/reflectors.csv`. To use only inline reflectors, explicitly
+disable file loading:
+
+```uci
+config reflectors
+    option files 'none'
+
+config reflector
+    option host 'global.irtt.lochnair.net'
+    list protocols 'irtt'
+```
+
+Use `list files '/path/to/reflectors.csv'` instead of `option files 'none'` to
+combine CSV files with inline reflectors. Omitting `files` keeps the default CSV;
+UCI discards empty string options, so `option files ''` does not disable it.

src/settings/mod.rs

@@ -270,6 +270,7 @@ impl NetworkSettings {
 #[derive(Clone, Debug, Deserialize, UciSection)]
 #[serde(default)]
 pub(crate) struct ReflectorSettings {
+    #[serde(deserialize_with = "deserialize_reflector_files")]
     pub(crate) files: Vec<String>,
     pub(crate) countries: Vec<String>,
 
@@ -472,3 +473,25 @@ where
     let value = String::deserialize(deserializer)?;
     value.parse().map_err(de::Error::custom)
 }
+
+// UCI drops empty string options; `option files 'none'` disables file loading.
+fn deserialize_reflector_files<'de, D>(deserializer: D) -> Result<Vec<String>, D::Error>
+where
+    D: Deserializer<'de>,
+{
+    #[derive(Deserialize)]
+    #[serde(untagged)]
+    enum Files {
+        List(Vec<String>),
+        String(String),
+    }
+
+    match Files::deserialize(deserializer)? {
+        Files::List(files) => Ok(files),
+        Files::String(value) if value.trim().is_empty() || value.trim() == "none" => Ok(Vec::new()),
+        Files::String(_) => Err(de::Error::custom(
+            "reflector files must be a list, an empty string, or none",
+        )),
+    }
+}
+