Merge #208

208: cleanups: simplify ledger::Message r=koivunej a=ljedrz

It seems to me that we don't need `ledger::Message` to be generic; I get the point behind the tag, but IMO its handling is simple enough to not require it at all.

Originally I also removed what vscode suggested to be an unused import, but my trust in it seems to have been misplaced 😆.

Co-authored-by: ljedrz <ljedrz@gmail.com>

bitswap/src/behaviour.rs

@@ -6,7 +6,7 @@
 //! The `Bitswap` struct implements the `NetworkBehaviour` trait. When used, it
 //! will allow providing and reciving IPFS blocks.
 use crate::block::Block;
-use crate::ledger::{Ledger, Message, Priority, I, O};
+use crate::ledger::{Ledger, Message, Priority};
 use crate::protocol::BitswapConfig;
 use crate::strategy::{Strategy, StrategyEvent};
 use fnv::FnvHashSet;
@@ -23,7 +23,7 @@ use std::collections::{HashMap, VecDeque};
 /// Network behaviour that handles sending and receiving IPFS blocks.
 pub struct Bitswap<TStrategy> {
     /// Queue of events to report to the user.
-    events: VecDeque<NetworkBehaviourAction<Message<O>, ()>>,
+    events: VecDeque<NetworkBehaviourAction<Message, ()>>,
     /// List of peers to send messages to.
     target_peers: FnvHashSet<PeerId>,
     /// Ledger
@@ -185,7 +185,7 @@ impl<TStrategy> Bitswap<TStrategy> {
 }
 
 impl<TStrategy: Strategy> NetworkBehaviour for Bitswap<TStrategy> {
-    type ProtocolsHandler = OneShotHandler<BitswapConfig, Message<O>, InnerMessage>;
+    type ProtocolsHandler = OneShotHandler<BitswapConfig, Message, InnerMessage>;
     type OutEvent = ();
 
     fn new_handler(&mut self) -> Self::ProtocolsHandler {
@@ -315,14 +315,14 @@ impl<TStrategy: Strategy> NetworkBehaviour for Bitswap<TStrategy> {
 #[derive(Debug)]
 pub enum InnerMessage {
     /// We received a `Message` from a remote.
-    Rx(Message<I>),
+    Rx(Message),
     /// We successfully sent a `Message`.
     Tx,
 }
 
-impl From<Message<I>> for InnerMessage {
+impl From<Message> for InnerMessage {
     #[inline]
-    fn from(message: Message<I>) -> InnerMessage {
+    fn from(message: Message) -> InnerMessage {
         InnerMessage::Rx(message)
     }
 }

bitswap/src/ledger.rs

@@ -3,7 +3,6 @@ use crate::block::Block;
 use crate::error::BitswapError;
 use crate::prefix::Prefix;
 use core::convert::TryFrom;
-use core::marker::PhantomData;
 use libipld::cid::Cid;
 use prost::Message as ProstMessage;
 use std::collections::HashMap;
@@ -36,21 +35,21 @@ impl Ledger {
         Self::default()
     }
 
-    pub fn send_block(&mut self, block: Block) -> Message<O> {
-        let mut message = Message::new();
+    pub fn send_block(&mut self, block: Block) -> Message {
+        let mut message = Message::default();
         message.add_block(block);
         message
     }
 
-    pub fn want_block(&mut self, cid: &Cid, priority: Priority) -> Message<O> {
-        let mut message = Message::new();
+    pub fn want_block(&mut self, cid: &Cid, priority: Priority) -> Message {
+        let mut message = Message::default();
         message.want_block(cid, priority);
         message
     }
 
-    pub fn cancel_block(&mut self, cid: &Cid) -> Option<Message<O>> {
+    pub fn cancel_block(&mut self, cid: &Cid) -> Option<Message> {
         if self.sent_want_list.contains_key(cid) {
-            let mut message = Message::new();
+            let mut message = Message::default();
             message.cancel_block(cid);
             Some(message)
         } else {
@@ -58,7 +57,7 @@ impl Ledger {
         }
     }
 
-    pub fn update_outgoing_stats(&mut self, message: &Message<O>) {
+    pub fn update_outgoing_stats(&mut self, message: &Message) {
         self.sent_blocks += message.blocks.len() as u64;
         for cid in message.cancel() {
             self.sent_want_list.remove(cid);
@@ -68,7 +67,7 @@ impl Ledger {
         }
     }
 
-    pub fn update_incoming_stats(&mut self, message: &Message<I>) {
+    pub fn update_incoming_stats(&mut self, message: &Message) {
         for cid in message.cancel() {
             self.received_want_list.remove(cid);
         }
@@ -96,16 +95,9 @@ impl Ledger {
     }
 }
 
-#[derive(Debug, Clone, PartialEq)]
-pub struct I;
-#[derive(Debug, Clone, PartialEq)]
-pub struct O;
-
 /// A bitswap message.
-#[derive(Clone, PartialEq)]
-pub struct Message<T> {
-    /// Message tag
-    _phantom_data: PhantomData<T>,
+#[derive(Clone, PartialEq, Default)]
+pub struct Message {
     /// List of wanted blocks.
     want: HashMap<Cid, Priority>,
     /// List of blocks to cancel.
@@ -116,23 +108,7 @@ pub struct Message<T> {
     blocks: Vec<Block>,
 }
 
-impl<T> Default for Message<T> {
-    fn default() -> Self {
-        Message {
-            _phantom_data: PhantomData,
-            want: HashMap::new(),
-            cancel: Vec::new(),
-            full: false,
-            blocks: Vec::new(),
-        }
-    }
-}
-
-impl<T> Message<T> {
-    pub fn new() -> Self {
-        Self::default()
-    }
-
+impl Message {
     /// Returns the list of blocks.
     pub fn blocks(&self) -> &[Block] {
         &self.blocks
@@ -175,7 +151,7 @@ impl<T> Message<T> {
     }
 }
 
-impl Into<Vec<u8>> for &Message<O> {
+impl Into<Vec<u8>> for &Message {
     fn into(self) -> Vec<u8> {
         let mut proto = bitswap_pb::Message::default();
         let mut wantlist = bitswap_pb::message::Wantlist::default();
@@ -208,18 +184,23 @@ impl Into<Vec<u8>> for &Message<O> {
     }
 }
 
-impl Message<O> {
+impl Message {
     /// Turns this `Message` into a message that can be sent to a substream.
     pub fn to_bytes(&self) -> Vec<u8> {
         self.into()
     }
+
+    /// Creates a `Message` from bytes that were received from a substream.
+    pub fn from_bytes(bytes: &[u8]) -> Result<Self, BitswapError> {
+        Self::try_from(bytes)
+    }
 }
 
-impl TryFrom<&[u8]> for Message<I> {
+impl TryFrom<&[u8]> for Message {
     type Error = BitswapError;
     fn try_from(bytes: &[u8]) -> Result<Self, Self::Error> {
         let proto: bitswap_pb::Message = bitswap_pb::Message::decode(bytes)?;
-        let mut message = Message::new();
+        let mut message = Message::default();
         for entry in proto.wantlist.unwrap_or_default().entries {
             let cid = Cid::try_from(entry.block)?;
             if entry.cancel {
@@ -241,14 +222,7 @@ impl TryFrom<&[u8]> for Message<I> {
     }
 }
 
-impl Message<I> {
-    /// Creates a `Message` from bytes that were received from a substream.
-    pub fn from_bytes(bytes: &[u8]) -> Result<Self, BitswapError> {
-        Self::try_from(bytes)
-    }
-}
-
-impl<T> std::fmt::Debug for Message<T> {
+impl std::fmt::Debug for Message {
     fn fmt(&self, fmt: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
         for (cid, priority) in self.want() {
             writeln!(fmt, "want: {} {}", cid.to_string(), priority)?;

bitswap/src/protocol.rs

@@ -4,7 +4,7 @@ use crate::error::BitswapError;
 /// The protocol works the following way:
 ///
 /// - TODO
-use crate::ledger::{Message, I, O};
+use crate::ledger::Message;
 use core::future::Future;
 use core::iter;
 use core::pin::Pin;
@@ -33,7 +33,7 @@ impl<TSocket> InboundUpgrade<TSocket> for BitswapConfig
 where
     TSocket: AsyncRead + AsyncWrite + Send + Unpin + 'static,
 {
-    type Output = Message<I>;
+    type Output = Message;
     type Error = BitswapError;
     #[allow(clippy::type_complexity)]
     type Future = Pin<Box<dyn Future<Output = Result<Self::Output, Self::Error>> + Send>>;
@@ -50,7 +50,7 @@ where
     }
 }
 
-impl UpgradeInfo for Message<O> {
+impl UpgradeInfo for Message {
     type Info = &'static [u8];
     type InfoIter = iter::Once<Self::Info>;
 
@@ -60,7 +60,7 @@ impl UpgradeInfo for Message<O> {
     }
 }
 
-impl<TSocket> OutboundUpgrade<TSocket> for Message<O>
+impl<TSocket> OutboundUpgrade<TSocket> for Message
 where
     TSocket: AsyncRead + AsyncWrite + Send + Unpin + 'static,
 {