Improve Aggregation function & config parser

Refactor aggregation function
Rename visiting_url to url, as they are always the same (see upstream engine scalping).
Refactor parsing function to be more readable.

src/engines/duckduckgo.rs

@@ -147,7 +147,7 @@ impl SearchEngine for DuckDuckGo {
                     vec!["duckduckgo".to_string()],
                 )
             })
-            .map(|search_result| (search_result.visiting_url.clone(), search_result))
+            .map(|search_result| (search_result.url.clone(), search_result))
             .collect())
     }
 }

src/engines/engine_models.rs

@@ -43,7 +43,7 @@ impl fmt::Display for EngineError {
 
 impl error_stack::Context for EngineError {}
 
-/// A trait to define common behaviour for all search engines.
+/// A trait to define common behavior for all search engines.
 #[async_trait::async_trait]
 pub trait SearchEngine {
     async fn fetch_html_from_upstream(
@@ -56,7 +56,7 @@ pub trait SearchEngine {
         Ok(reqwest::Client::new()
             .get(url)
             .timeout(Duration::from_secs(request_timeout as u64)) // Add timeout to request to avoid DDOSing the server
-            .headers(header_map) // add spoofed headers to emulate human behaviour
+            .headers(header_map) // add spoofed headers to emulate human behavior
             .send()
             .await
             .into_report()

src/engines/searx.rs

@@ -137,7 +137,7 @@ impl SearchEngine for Searx {
                     vec!["searx".to_string()],
                 )
             })
-            .map(|search_result| (search_result.visiting_url.clone(), search_result))
+            .map(|search_result| (search_result.url.clone(), search_result))
             .collect())
     }
 }