add: bitswap wantlist getters

compared to original version, attempt to differentiate peer vs. local at
method level. could probably be at the ipfs level as well?

bitswap/src/behaviour.rs

@@ -45,6 +45,16 @@ impl<TStrategy> Bitswap<TStrategy> {
         }
     }
 
+    /// Return the wantlist of the local node
+    pub fn local_wantlist(&self) -> Vec<(Cid, Priority)> {
+        self.wanted_blocks.iter().map(|(cid, prio)| (cid.clone(), *prio)).collect()
+    }
+
+    /// Return the wantlist of a peer, if known
+    pub fn peer_wantlist(&self, peer: &PeerId) -> Option<Vec<(Cid, Priority)>> {
+        self.connected_peers.get(peer).map(Ledger::wantlist)
+    }
+
     /// Connect to peer.
     ///
     /// Called from Kademlia behaviour.

bitswap/src/ledger.rs

@@ -70,6 +70,11 @@ impl Ledger {
             self.received_want_list.insert(cid.to_owned(), *priority);
         }
     }
+
+    /// Returns the blocks wanted by the peer in unspecified order
+    pub fn wantlist(&self) -> Vec<(Cid, Priority)> {
+        self.received_want_list.iter().map(|(cid, prio)| (cid.clone(), *prio)).collect()
+    }
 }
 
 #[derive(Debug, Clone, PartialEq)]

src/lib.rs

@@ -635,7 +635,12 @@ impl<Types: SwarmTypes> Future for IpfsFuture<Types> {
                         let _ = ret.send(self.swarm.pubsub().subscribed_topics());
                     }
                     IpfsEvent::WantList(peer, ret) => {
-                        todo!()
+                        let list = if let Some(peer) = peer {
+                            self.swarm.bitswap().peer_wantlist(&peer).unwrap_or_default()
+                        } else {
+                            self.swarm.bitswap().local_wantlist()
+                        };
+                        let _ = ret.send(list);
                     }
                     IpfsEvent::BitswapStats(ret) => {
                         todo!()

src/p2p/behaviour.rs

@@ -236,6 +236,10 @@ impl<TSwarmTypes: SwarmTypes> Behaviour<TSwarmTypes> {
     pub fn pubsub(&mut self) -> &mut Pubsub {
         &mut self.pubsub
     }
+
+    pub fn bitswap(&mut self) -> &mut Bitswap<TSwarmTypes::TStrategy> {
+        &mut self.bitswap
+    }
 }
 
 /// Create a IPFS behaviour with the IPFS bootstrap nodes.