option to disable retries

index.js

@@ -128,6 +128,7 @@ class DHT extends EventEmitter {
     const req = this.io.createRequest({ id: null, host, port }, token, command, target, value)
 
     if (opts && opts.socket) req.socket = opts.socket
+    if (opts && opts.retry === false) req.retries = 0
 
     return new Promise((resolve, reject) => {
       req.onresponse = resolve

lib/io.js

@@ -204,6 +204,7 @@ class Request {
     this.target = target
     this.value = value
     this.sent = 0
+    this.retries = 3
     this.destroyed = false
 
     this.oncycle = noop
@@ -388,7 +389,7 @@ function noop () {}
 function oncycle (req) {
   req._timeout = null
   req.oncycle(req)
-  if (req.sent === 3) {
+  if (req.sent >= req.retries) {
     req.destroy(TIMEOUT)
     req._io.ontimeout(req)
   } else {

test.js

@@ -125,6 +125,38 @@ tape('timeouts', async function (t) {
   b.destroy()
 })
 
+tape('request with/without retries', async function (t) {
+  const [bootstrap, a, b] = await makeSwarm(3)
+  let tries = 0
+
+  b.on('request', function (req) {
+    if (req.command === 'nope') {
+      tries++
+      t.pass('ignoring request')
+    }
+  })
+
+  try {
+    await a.request({ command: 'nope', target: Buffer.alloc(32) }, { host: '127.0.0.1', port: b.address().port })
+  } catch {
+    // do nothing
+  }
+
+  t.same(tries, 3)
+
+  try {
+    await a.request({ command: 'nope', target: Buffer.alloc(32) }, { host: '127.0.0.1', port: b.address().port }, { retry: false })
+  } catch {
+    // do nothing
+  }
+
+  t.same(tries, 4)
+
+  bootstrap.destroy()
+  a.destroy()
+  b.destroy()
+})
+
 tape('shorthand commit', async function (t) {
   const swarm = await makeSwarm(40)