enh: adds fallback url for expired short codes

crates/url_shortner/src/domain/action/public_api.rs

@@ -28,9 +28,11 @@ pub async fn redirect_to_url(
             info!("redirecting to: {}", base_url);
             Ok(Redirect::to(base_url.to_string()))
         }
-        None => Err(AppError::InvalidRequest(format!(
-            "No URL found for short code: {}",
-            url_short_code.0
-        ))),
+        None => {
+            error!("No URL found for short code: {}", url_short_code.0);
+            Ok(Redirect::to(
+                app_state.expired_short_code_fallback_url.to_string(),
+            ))
+        }
     }
 }

crates/url_shortner/src/environment.rs

@@ -25,6 +25,7 @@ pub struct AppConfig {
     pub max_retries_for_shortening: u8,
     pub log_unprocessible_req_body: Vec<String>,
     pub max_allowed_req_size: usize,
+    pub expired_short_code_fallback_url: String,
 }
 
 #[derive(Clone)]
@@ -41,6 +42,7 @@ pub struct AppState {
     pub max_retries_for_shortening: u8,
     pub log_unprocessible_req_body: Vec<String>,
     pub max_allowed_req_size: usize,
+    pub expired_short_code_fallback_url: String,
 }
 
 impl AppState {
@@ -64,6 +66,7 @@ impl AppState {
             max_retries_for_shortening: app_config.max_retries_for_shortening,
             log_unprocessible_req_body: app_config.log_unprocessible_req_body,
             max_allowed_req_size: app_config.max_allowed_req_size,
+            expired_short_code_fallback_url: app_config.expired_short_code_fallback_url,
         }
     }
 }

dhall-configs/dev/url-shortner.dhall

@@ -33,4 +33,5 @@ in {
     short_code_length = 6,
     shortened_base_url = "http://localhost:9023",
     max_retries_for_shortening = 5,
+    expired_short_code_fallback_url = "https://nammayatri.in",
 }