From 4c3da7bad29afa6b8bc38959dc5ea32d9e900a59 Mon Sep 17 00:00:00 2001
From: Franck Royer <franck@status.im>
Date: Mon, 25 Jul 2022 12:43:17 +1000
Subject: [PATCH] refactor: Use common code for filter and light push

---
 src/lib/wait_for_remote_peer.ts | 76 +++++++++++++++------------------
 1 file changed, 35 insertions(+), 41 deletions(-)

diff --git a/src/lib/wait_for_remote_peer.ts b/src/lib/wait_for_remote_peer.ts
index 1c040c1902..9ccee6d542 100644
--- a/src/lib/wait_for_remote_peer.ts
+++ b/src/lib/wait_for_remote_peer.ts
@@ -1,5 +1,6 @@
-import { PeerProtocolsChangeData } from "@libp2p/interface-peer-store";
+import { Peer, PeerProtocolsChangeData } from "@libp2p/interface-peer-store";
 import debug from "debug";
+import type { Libp2p } from "libp2p";
 
 import { StoreCodecs } from "./constants";
 import { Protocols, Waku } from "./waku";
@@ -8,6 +9,11 @@ import { LightPushCodec } from "./waku_light_push";
 
 const log = debug("waku:wait-for-remote-peer");
 
+interface WakuProtocol {
+  libp2p: Libp2p;
+  peers: () => Promise<Peer[]>;
+}
+
 /**
  * Wait for a remote peer to be ready given the passed protocols.
  * Useful when using the [[CreateOptions.bootstrap]] with [[Waku.create]].
@@ -76,49 +82,11 @@ export async function waitForRemotePeer(
   }
 
   if (protocols.includes(Protocols.LightPush)) {
-    const lightPushPromise = (async (): Promise<void> => {
-      const peers = await waku.lightPush.peers();
-
-      if (peers.length) {
-        log("Light Push peer found: ", peers[0].id.toString());
-        return;
-      }
-
-      await new Promise<void>((resolve) => {
-        const cb = (evt: CustomEvent<PeerProtocolsChangeData>): void => {
-          if (evt.detail.protocols.includes(LightPushCodec)) {
-            log("Resolving for", LightPushCodec, evt.detail.protocols);
-            waku.libp2p.peerStore.removeEventListener("change:protocols", cb);
-            resolve();
-          }
-        };
-        waku.libp2p.peerStore.addEventListener("change:protocols", cb);
-      });
-    })();
-    promises.push(lightPushPromise);
+    promises.push(waitForConnectedPeer(waku.lightPush, LightPushCodec));
   }
 
   if (protocols.includes(Protocols.Filter)) {
-    const filterPromise = (async (): Promise<void> => {
-      const peers = await waku.filter.peers();
-
-      if (peers.length) {
-        log("Filter peer found: ", peers[0].id.toString());
-        return;
-      }
-
-      await new Promise<void>((resolve) => {
-        const cb = (evt: CustomEvent<PeerProtocolsChangeData>): void => {
-          if (evt.detail.protocols.includes(FilterCodec)) {
-            log("Resolving for", FilterCodec, evt.detail.protocols);
-            waku.libp2p.peerStore.removeEventListener("change:protocols", cb);
-            resolve();
-          }
-        };
-        waku.libp2p.peerStore.addEventListener("change:protocols", cb);
-      });
-    })();
-    promises.push(filterPromise);
+    promises.push(waitForConnectedPeer(waku.lightPush, FilterCodec));
   }
 
   if (timeoutMs) {
@@ -132,6 +100,32 @@ export async function waitForRemotePeer(
   }
 }
 
+/**
+ * Wait for a peer with the given protocol to be connected.
+ */
+async function waitForConnectedPeer(
+  waku: WakuProtocol,
+  codec: string
+): Promise<void> {
+  const peers = await waku.peers();
+
+  if (peers.length) {
+    log(`${codec} peer found: `, peers[0].id.toString());
+    return;
+  }
+
+  await new Promise<void>((resolve) => {
+    const cb = (evt: CustomEvent<PeerProtocolsChangeData>): void => {
+      if (evt.detail.protocols.includes(codec)) {
+        log("Resolving for", codec, evt.detail.protocols);
+        waku.libp2p.peerStore.removeEventListener("change:protocols", cb);
+        resolve();
+      }
+    };
+    waku.libp2p.peerStore.addEventListener("change:protocols", cb);
+  });
+}
+
 const awaitTimeout = (ms: number, rejectReason: string): Promise<void> =>
   new Promise((_resolve, reject) => setTimeout(() => reject(rejectReason), ms));