refactor: re-use wantlist.Entry type wherever it makes sense

it seems to make sense since, in each place, the Key and Priority
represent the same information

b/c you know the saying...

"It is better to have 100 functions operate on one data structure than
10 functions on 10 data structures."

License: MIT
Signed-off-by: Brian Tiger Chow <brian@perfmode.com>

exchange/bitswap/bitswap.go

@@ -172,7 +172,7 @@ func (bs *bitswap) sendWantListTo(ctx context.Context, peers <-chan peer.Peer) e
 	}
 	message := bsmsg.New()
 	for _, wanted := range bs.wantlist.Entries() {
-		message.AddEntry(wanted.Value, wanted.Priority)
+		message.AddEntry(wanted.Key, wanted.Priority)
 	}
 	wg := sync.WaitGroup{}
 	for peerToQuery := range peers {
@@ -210,7 +210,7 @@ func (bs *bitswap) sendWantlistToProviders(ctx context.Context, wantlist *wl.Wan
 	message := bsmsg.New()
 	message.SetFull(true)
 	for _, e := range bs.wantlist.Entries() {
-		message.AddEntry(e.Value, e.Priority)
+		message.AddEntry(e.Key, e.Priority)
 	}
 
 	ps := pset.NewPeerSet()
@@ -229,7 +229,7 @@ func (bs *bitswap) sendWantlistToProviders(ctx context.Context, wantlist *wl.Wan
 					bs.send(ctx, prov, message)
 				}
 			}
-		}(e.Value)
+		}(e.Key)
 	}
 	wg.Wait()
 }

exchange/bitswap/message/message.go

@@ -5,6 +5,7 @@ import (
 
 	blocks "github.com/jbenet/go-ipfs/blocks"
 	pb "github.com/jbenet/go-ipfs/exchange/bitswap/message/internal/pb"
+	wantlist "github.com/jbenet/go-ipfs/exchange/bitswap/wantlist"
 	inet "github.com/jbenet/go-ipfs/net"
 	u "github.com/jbenet/go-ipfs/util"
 
@@ -64,9 +65,8 @@ func newMsg() *impl {
 }
 
 type Entry struct {
-	Key      u.Key
-	Priority int
-	Cancel   bool
+	wantlist.Entry
+	Cancel bool
 }
 
 func newMessageFromProto(pbm pb.Message) BitSwapMessage {
@@ -121,9 +121,11 @@ func (m *impl) addEntry(k u.Key, priority int, cancel bool) {
 		e.Cancel = cancel
 	} else {
 		m.wantlist[k] = &Entry{
-			Key:      k,
-			Priority: priority,
-			Cancel:   cancel,
+			Entry: wantlist.Entry{
+				Key:      k,
+				Priority: priority,
+			},
+			Cancel: cancel,
 		}
 	}
 }

exchange/bitswap/strategy/ledgermanager.go

@@ -61,7 +61,7 @@ func (lm *LedgerManager) taskWorker(ctx context.Context) {
 			}
 			continue
 		}
-		block, err := lm.bs.Get(nextTask.Key)
+		block, err := lm.bs.Get(nextTask.Entry.Key)
 		if err != nil {
 			continue // TODO maybe return an error
 		}

exchange/bitswap/strategy/taskqueue.go

@@ -1,6 +1,7 @@
 package strategy
 
 import (
+	wantlist "github.com/jbenet/go-ipfs/exchange/bitswap/wantlist"
 	peer "github.com/jbenet/go-ipfs/peer"
 	u "github.com/jbenet/go-ipfs/util"
 )
@@ -20,9 +21,8 @@ func newTaskQueue() *taskQueue {
 }
 
 type task struct {
-	Key           u.Key
-	Target        peer.Peer
-	theirPriority int
+	Entry  wantlist.Entry
+	Target peer.Peer
 }
 
 // Push currently adds a new task to the end of the list
@@ -31,13 +31,15 @@ func (tl *taskQueue) Push(block u.Key, priority int, to peer.Peer) {
 	if task, ok := tl.taskmap[taskKey(to, block)]; ok {
 		// TODO: when priority queue is implemented,
 		//       rearrange this task
-		task.theirPriority = priority
+		task.Entry.Priority = priority
 		return
 	}
 	task := &task{
-		Key:           block,
-		Target:        to,
-		theirPriority: priority,
+		Entry: wantlist.Entry{
+			Key:      block,
+			Priority: priority,
+		},
+		Target: to,
 	}
 	tl.tasks = append(tl.tasks, task)
 	tl.taskmap[taskKey(to, block)] = task
@@ -52,9 +54,9 @@ func (tl *taskQueue) Pop() *task {
 		//		 the same block from multiple peers
 		out = tl.tasks[0]
 		tl.tasks = tl.tasks[1:]
-		delete(tl.taskmap, taskKey(out.Target, out.Key))
+		delete(tl.taskmap, taskKey(out.Target, out.Entry.Key))
 		// Filter out blocks that have been cancelled
-		if out.theirPriority >= 0 {
+		if out.Entry.Priority >= 0 { // FIXME separate the "cancel" signal from priority
 			break
 		}
 	}
@@ -66,7 +68,7 @@ func (tl *taskQueue) Pop() *task {
 func (tl *taskQueue) Remove(k u.Key, p peer.Peer) {
 	t, ok := tl.taskmap[taskKey(p, k)]
 	if ok {
-		t.theirPriority = -1
+		t.Entry.Priority = -1
 	}
 }
 

exchange/bitswap/wantlist/wantlist.go

@@ -18,7 +18,7 @@ func New() *Wantlist {
 }
 
 type Entry struct {
-	Value    u.Key
+	Key      u.Key
 	Priority int
 }
 
@@ -29,7 +29,7 @@ func (w *Wantlist) Add(k u.Key, priority int) {
 		return
 	}
 	w.set[k] = &Entry{
-		Value:    k,
+		Key:      k,
 		Priority: priority,
 	}
 }