improve ws protocol struct naming and documentation

crates/ws_protocol/src/outgoing/announce.rs

@@ -0,0 +1,15 @@
+use serde::{Deserialize, Serialize};
+
+use crate::common::*;
+
+/// Plain response to an AnnounceRequest
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+pub struct AnnounceResponse {
+    pub action: AnnounceAction,
+    pub info_hash: InfoHash,
+    /// Client checks if this is null, not clear why
+    pub complete: usize,
+    pub incomplete: usize,
+    #[serde(rename = "interval")]
+    pub announce_interval: usize, // Default 2 min probably
+}

crates/ws_protocol/src/outgoing/answer.rs

@@ -0,0 +1,17 @@
+use serde::{Deserialize, Serialize};
+
+use crate::common::*;
+
+/// Message sent to peer when other peer has replied to its WebRTC offer
+///
+/// Sent if fields answer, to_peer_id and offer_id are set in announce request
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+pub struct AnswerOutMessage {
+    /// Always "announce"
+    pub action: AnnounceAction,
+    /// Note: if equal to client peer_id, client ignores answer
+    pub peer_id: PeerId,
+    pub info_hash: InfoHash,
+    pub answer: RtcAnswer,
+    pub offer_id: OfferId,
+}

crates/ws_protocol/src/outgoing/error.rs

@@ -0,0 +1,24 @@
+use std::borrow::Cow;
+
+use serde::{Deserialize, Serialize};
+
+use crate::common::*;
+
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+pub struct ErrorResponse {
+    #[serde(rename = "failure reason")]
+    pub failure_reason: Cow<'static, str>,
+    /// Action of original request
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub action: Option<ErrorResponseAction>,
+    // Should not be renamed
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub info_hash: Option<InfoHash>,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+#[serde(rename_all = "lowercase")]
+pub enum ErrorResponseAction {
+    Announce,
+    Scrape,
+}

crates/ws_protocol/src/outgoing/mod.rs

@@ -0,0 +1,44 @@
+use serde::{Deserialize, Serialize};
+
+pub mod announce;
+pub mod answer;
+pub mod error;
+pub mod offer;
+pub mod scrape;
+
+pub use announce::*;
+pub use answer::*;
+pub use error::*;
+pub use offer::*;
+pub use scrape::*;
+
+/// Message sent by tracker
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+#[serde(untagged)]
+pub enum OutMessage {
+    OfferOutMessage(OfferOutMessage),
+    AnswerOutMessage(AnswerOutMessage),
+    AnnounceResponse(AnnounceResponse),
+    ScrapeResponse(ScrapeResponse),
+    ErrorResponse(ErrorResponse),
+}
+
+impl OutMessage {
+    #[inline]
+    pub fn to_ws_message(&self) -> tungstenite::Message {
+        ::tungstenite::Message::from(::serde_json::to_string(&self).unwrap())
+    }
+
+    #[inline]
+    pub fn from_ws_message(message: ::tungstenite::Message) -> ::anyhow::Result<Self> {
+        use tungstenite::Message::{Binary, Text};
+
+        let mut text: Vec<u8> = match message {
+            Text(text) => text.into(),
+            Binary(bytes) => String::from_utf8(bytes)?.into(),
+            _ => return Err(anyhow::anyhow!("Message is neither text nor bytes")),
+        };
+
+        Ok(::simd_json::serde::from_slice(&mut text)?)
+    }
+}

crates/ws_protocol/src/outgoing/offer.rs

@@ -0,0 +1,22 @@
+use serde::{Deserialize, Serialize};
+
+use crate::common::*;
+
+/// Message sent to peer when other peer wants to initiate a WebRTC connection
+///
+/// One is sent for each offer in an announce request
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+pub struct OfferOutMessage {
+    /// Always "announce"
+    pub action: AnnounceAction,
+    /// Peer id of peer sending offer
+    ///
+    /// Note: if equal to client peer_id, reference client ignores offer
+    pub peer_id: PeerId,
+    /// Torrent info hash
+    pub info_hash: InfoHash,
+    /// Gets copied from AnnounceRequestOffer
+    pub offer: RtcOffer,
+    /// Gets copied from AnnounceRequestOffer
+    pub offer_id: OfferId,
+}

crates/ws_protocol/src/outgoing/scrape.rs

@@ -0,0 +1,19 @@
+use hashbrown::HashMap;
+use serde::{Deserialize, Serialize};
+
+use crate::common::*;
+
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+pub struct ScrapeResponse {
+    pub action: ScrapeAction,
+    pub files: HashMap<InfoHash, ScrapeStatistics>,
+    // It looks like `flags` field is ignored in reference client
+    // pub flags: HashMap<String, usize>,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+pub struct ScrapeStatistics {
+    pub complete: usize,
+    pub incomplete: usize,
+    pub downloaded: usize,
+}