From 531933761a85a7f3be11332cc002c6f3e4b4d1d4 Mon Sep 17 00:00:00 2001
From: Alex Grintsvayg <git@grin.io>
Date: Mon, 25 Jun 2018 15:56:45 -0400
Subject: [PATCH] remove sendCancelable

---
 dht/bootstrap.go   |  3 +--
 dht/dht.go         |  3 +--
 dht/node.go        | 14 ++------------
 dht/node_finder.go |  3 +--
 dht/token_cache.go |  3 +--
 5 files changed, 6 insertions(+), 20 deletions(-)

diff --git a/dht/bootstrap.go b/dht/bootstrap.go
index 0ca6864..2bb9230 100644
--- a/dht/bootstrap.go
+++ b/dht/bootstrap.go
@@ -132,14 +132,13 @@ func (b *BootstrapNode) ping(c Contact) {
 	b.stop.Add(1)
 	defer b.stop.Done()
 
-	resCh, cancel := b.SendCancelable(c, Request{Method: pingMethod})
+	resCh := b.SendAsync(c, Request{Method: pingMethod})
 
 	var res *Response
 
 	select {
 	case res = <-resCh:
 	case <-b.stop.Ch():
-		cancel()
 		return
 	}
 
diff --git a/dht/dht.go b/dht/dht.go
index a37b42f..37f16de 100644
--- a/dht/dht.go
+++ b/dht/dht.go
@@ -318,7 +318,7 @@ func (dht *DHT) storeOnNode(hash bits.Bitmap, c Contact) {
 
 	token := dht.tokenCache.Get(c, hash, dht.stop.Ch())
 
-	resCh, cancel := dht.node.SendCancelable(c, Request{
+	resCh := dht.node.SendAsync(c, Request{
 		Method: storeMethod,
 		StoreArgs: &storeArgs{
 			BlobHash: hash,
@@ -334,7 +334,6 @@ func (dht *DHT) storeOnNode(hash bits.Bitmap, c Contact) {
 		select {
 		case <-resCh:
 		case <-dht.stop.Ch():
-			cancel()
 		}
 	}()
 }
diff --git a/dht/node.go b/dht/node.go
index e2343e5..7bc828a 100644
--- a/dht/node.go
+++ b/dht/node.go
@@ -1,7 +1,6 @@
 package dht
 
 import (
-	"context"
 	"encoding/hex"
 	"net"
 	"strings"
@@ -387,7 +386,7 @@ type SendOptions struct {
 
 // SendAsync sends a transaction and returns a channel that will eventually contain the transaction response
 // The response channel is closed when the transaction is completed or times out.
-func (n *Node) SendAsync(ctx context.Context, contact Contact, req Request, options ...SendOptions) <-chan *Response {
+func (n *Node) SendAsync(contact Contact, req Request, options ...SendOptions) <-chan *Response {
 	ch := make(chan *Response, 1)
 
 	if contact.ID.Equals(n.id) {
@@ -429,9 +428,6 @@ func (n *Node) SendAsync(ctx context.Context, contact Contact, req Request, opti
 				return
 			case <-n.stop.Ch():
 				return
-			case <-ctx.Done():
-				// TODO: canceling these requests doesn't do much. we can probably stop supporting this feature and just use async
-				return
 			case <-time.After(udpTimeout):
 			}
 		}
@@ -446,13 +442,7 @@ func (n *Node) SendAsync(ctx context.Context, contact Contact, req Request, opti
 // Send sends a transaction and blocks until the response is available. It returns a response, or nil
 // if the transaction timed out.
 func (n *Node) Send(contact Contact, req Request, options ...SendOptions) *Response {
-	return <-n.SendAsync(context.Background(), contact, req, options...)
-}
-
-// SendCancelable sends the transaction asynchronously and allows the transaction to be canceled
-func (n *Node) SendCancelable(contact Contact, req Request, options ...SendOptions) (<-chan *Response, context.CancelFunc) {
-	ctx, cancel := context.WithCancel(context.Background())
-	return n.SendAsync(ctx, contact, req, options...), cancel
+	return <-n.SendAsync(contact, req, options...)
 }
 
 // CountActiveTransactions returns the number of transactions in the manager
diff --git a/dht/node_finder.go b/dht/node_finder.go
index 00c5c2a..a455374 100644
--- a/dht/node_finder.go
+++ b/dht/node_finder.go
@@ -1,7 +1,6 @@
 package dht
 
 import (
-	"context"
 	"sort"
 	"sync"
 	"time"
@@ -223,7 +222,7 @@ func (cf *contactFinder) probe(cycleID string) *Contact {
 	}
 
 	var res *Response
-	resCh := cf.node.SendAsync(context.Background(), c, req)
+	resCh := cf.node.SendAsync(c, req)
 	select {
 	case res = <-resCh:
 	case <-cf.stop.Ch():
diff --git a/dht/token_cache.go b/dht/token_cache.go
index e080155..b10c514 100644
--- a/dht/token_cache.go
+++ b/dht/token_cache.go
@@ -41,7 +41,7 @@ func (tc *tokenCache) Get(c Contact, hash bits.Bitmap, cancelCh stopOnce.Chan) s
 		return token.token
 	}
 
-	resCh, cancel := tc.node.SendCancelable(c, Request{
+	resCh := tc.node.SendAsync(c, Request{
 		Method: findValueMethod,
 		Arg:    &hash,
 	})
@@ -51,7 +51,6 @@ func (tc *tokenCache) Get(c Contact, hash bits.Bitmap, cancelCh stopOnce.Chan) s
 	select {
 	case res = <-resCh:
 	case <-cancelCh:
-		cancel()
 		return ""
 	}