From e7c88acb83d6b7f25f38074f37668e17860dd518 Mon Sep 17 00:00:00 2001
From: Chad Nehemiah <chad.nehemiah94@gmail.com>
Date: Fri, 13 Jan 2023 15:32:14 -0500
Subject: [PATCH] feat: added allowPublishToZeroPeers as optional param to
 publish function (#395)

* feat: added Publish config as optional params (#367)

* test: added test for allowPublishZeroPeers param in publish function
---
 src/index.ts        | 10 +++++++---
 src/types.ts        |  4 ++++
 test/gossip.spec.ts | 19 ++++++++++++++++++-
 3 files changed, 29 insertions(+), 4 deletions(-)

diff --git a/src/index.ts b/src/index.ts
index b2d81fbf..3a9bb99a 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -52,7 +52,8 @@ import {
   DataTransform,
   rejectReasonFromAcceptance,
   MsgIdToStrFn,
-  MessageId
+  MessageId,
+  PublishOpts
 } from './types.js'
 import { buildRawMessage, validateToRawMessage } from './utils/buildRawMessage.js'
 import { msgIdFnStrictNoSign, msgIdFnStrictSign } from './utils/msgIdFn.js'
@@ -1995,7 +1996,7 @@ export class GossipSub extends EventEmitter<GossipsubEvents> implements PubSub<G
    *
    * For messages not from us, this class uses `forwardMessage`.
    */
-  async publish(topic: TopicStr, data: Uint8Array): Promise<PublishResult> {
+  async publish(topic: TopicStr, data: Uint8Array, opts?: PublishOpts): Promise<PublishResult> {
     const transformedData = this.dataTransform ? this.dataTransform.outboundTransform(topic, data) : data
 
     if (this.publishConfig == null) {
@@ -2018,7 +2019,10 @@ export class GossipSub extends EventEmitter<GossipsubEvents> implements PubSub<G
     const { tosend, tosendCount } = this.selectPeersToPublish(topic)
     const willSendToSelf = this.opts.emitSelf === true && this.subscriptions.has(topic)
 
-    if (tosend.size === 0 && !this.opts.allowPublishToZeroPeers && !willSendToSelf) {
+    // Current publish opt takes precedence global opts, while preserving false value
+    const allowPublishToZeroPeers = opts?.allowPublishToZeroPeers ?? this.opts.allowPublishToZeroPeers
+
+    if (tosend.size === 0 && !allowPublishToZeroPeers && !willSendToSelf) {
       throw Error('PublishError.InsufficientPeers')
     }
 
diff --git a/src/types.ts b/src/types.ts
index d1a009f8..714b5419 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -72,6 +72,10 @@ export enum SignaturePolicy {
   StrictNoSign = 'StrictNoSign'
 }
 
+export type PublishOpts = {
+  allowPublishToZeroPeers?: boolean
+}
+
 export enum PublishConfigType {
   Signing,
   Anonymous
diff --git a/test/gossip.spec.ts b/test/gossip.spec.ts
index 5453b3e4..b4985449 100644
--- a/test/gossip.spec.ts
+++ b/test/gossip.spec.ts
@@ -26,7 +26,8 @@ describe('gossip', () => {
         scoreParams: {
           IPColocationFactorThreshold: GossipsubDhi + 3
         },
-        maxInboundDataLength: 4000000
+        maxInboundDataLength: 4000000,
+        allowPublishToZeroPeers: false
       }
     })
   })
@@ -82,6 +83,22 @@ describe('gossip', () => {
     nodeASpy.pushGossip.restore()
   })
 
+  it('Should allow publishing to zero peers if flag is passed', async function () {
+    this.timeout(10e4)
+    const nodeA = nodes[0]
+    const topic = 'Z'
+
+    const publishResult = await nodeA.pubsub.publish(topic, uint8ArrayFromString('hey'), {
+      allowPublishToZeroPeers: true
+    })
+
+    // gossip happens during the heartbeat
+    await pEvent(nodeA.pubsub, 'gossipsub:heartbeat')
+
+    // should have sent message to peerB
+    expect(publishResult.recipients).to.deep.equal([])
+  })
+
   it('should reject incoming messages bigger than maxInboundDataLength limit', async function () {
     this.timeout(10e4)
     const nodeA = nodes[0]