aquatic_http: AnnounceRequest: make numwant optional, remove trackerid

aquatic_http/src/lib/handler.rs

@@ -143,10 +143,9 @@ pub fn handle_announce_requests(
             }
         }
 
-        let max_num_peers_to_take = if request.numwant <= 0 {
-            config.protocol.max_peers
-        } else {
-            request.numwant.min(config.protocol.max_peers)
+        let max_num_peers_to_take = match request.numwant {
+            Some(0) | None => config.protocol.max_peers,
+            Some(numwant) => numwant.min(config.protocol.max_peers),
         };
 
         let response_peers: Vec<ResponsePeer> = extract_response_peers(
@@ -161,7 +160,6 @@ pub fn handle_announce_requests(
             incomplete: torrent_data.num_leechers,
             announce_interval: config.protocol.peer_announce_interval,
             peers: response_peers,
-            tracker_id: "".to_string()
         });
 
         (request_sender_meta, response)

aquatic_http/src/lib/protocol/request.rs

@@ -13,8 +13,8 @@ pub struct AnnounceRequest {
     pub bytes_left: usize,
     pub event: AnnounceEvent,
     pub compact: bool,
-    /// Requested number of peers to return
-    pub numwant: usize,
+    /// Number of response peers wanted
+    pub numwant: Option<usize>,
 }
 
 
@@ -68,6 +68,17 @@ impl Request {
         }
 
         if location == "/announce" {
+            let numwant = if let Some(s) = data.get("numwant"){
+                let numwant = s.parse::<usize>()
+                    .map_err(|err|
+                        anyhow::anyhow!("parse 'numwant': {}", err)
+                    )?;
+                
+                Some(numwant)
+            } else {
+                None
+            };
+
             let request = AnnounceRequest {
                 info_hash: info_hashes.get(0)
                     .with_context(|| "no info_hash")
@@ -91,12 +102,7 @@ impl Request {
                 compact: data.get("compact")
                     .map(|s| s == "1")
                     .unwrap_or(true),
-                numwant: data.get("numwant")
-                    .with_context(|| "no numwant")
-                    .and_then(|s| s.parse()
-                    .map_err(|err|
-                        anyhow::anyhow!("parse 'numwant': {}", err)
-                    ))?,
+                numwant,
             };
 
             Ok(Request::Announce(request))

aquatic_http/src/lib/protocol/response.rs

@@ -40,7 +40,6 @@ pub struct ScrapeStatistics {
 pub struct AnnounceResponse {
     #[serde(rename = "interval")]
     pub announce_interval: usize,
-    pub tracker_id: String, // Optional??
     pub complete: usize,
     pub incomplete: usize,
     #[serde(