some changes

src/config/mod.rs

@@ -58,6 +58,7 @@ pub struct Config {
     pub asset_version: String,
     pub asset_cache_max_age_seconds: u64,
     pub file_cache_max_age_seconds: u64,
+    pub files_public_url: Option<String>,
     pub smtp: Option<crate::state::SmtpConfig>,
     pub registration_enabled: bool,
     pub account_confirmation_required: bool,
@@ -83,6 +84,8 @@ impl Config {
         let unconfirmed_account_ttl_days =
             values.positive_i64("UNCONFIRMED_ACCOUNT_TTL_DAYS", 3)?;
         let files_dir = values.get("FILES_DIR", "data/files");
+        let files_public_url =
+            crate::file_urls::normalize_public_base(values.optional("FILES_PUBLIC_URL"))?;
 
         let storage = match values
             .get("STORAGE_DRIVER", "local")
@@ -172,6 +175,7 @@ impl Config {
                 .nonnegative_u64("ASSET_CACHE_MAX_AGE_SECONDS", 600)?,
             file_cache_max_age_seconds: values
                 .nonnegative_u64("FILE_CACHE_MAX_AGE_SECONDS", 600)?,
+            files_public_url,
             smtp,
             registration_enabled: values.bool("REGISTRATION_ENABLED", false)?,
             account_confirmation_required: values.bool("ACCOUNT_CONFIRMATION_REQUIRED", false)?,

src/config/values.rs

@@ -16,6 +16,7 @@ const KNOWN_CONFIG_KEYS: &[&str] = &[
     "DATABASE_MAX_CONNECTIONS",
     "STATIC_DIR",
     "FILES_DIR",
+    "FILES_PUBLIC_URL",
     "STORAGE_DRIVER",
     "UPLOAD_MAX_SIZE_MB",
     "ASSET_CACHE_MAX_AGE_SECONDS",