fix(pubsub.peers): remove the requirement for a topic (#1125)

* fix(pubsub.peers): remove the requirement for a topic

* shorter code

Author: haoliangyu

src/core/components/pubsub.js

@@ -77,8 +77,13 @@ module.exports = function pubsub (self) {
         return setImmediate(() => callback(new Error(OFFLINE_ERROR)))
       }
 
+      if (typeof topic === 'function') {
+        callback = topic
+        topic = null
+      }
+
       const peers = Array.from(self._pubsub.peers.values())
-        .filter((peer) => peer.topics.has(topic))
+        .filter((peer) => topic ? peer.topics.has(topic) : true)
         .map((peer) => peer.info.id.toB58String())
 
       setImmediate(() => callback(null, peers))

src/http/api/resources/pubsub.js

@@ -102,13 +102,13 @@ exports.peers = {
     const topic = request.query.arg
     const ipfs = request.server.app.ipfs
 
-    if (!topic) {
-      return reply(new Error('Missing topic'))
-    }
-
     ipfs.pubsub.peers(topic, (err, peers) => {
       if (err) {
-        return reply(new Error(`Failed to find peers subscribed to ${topic}: ${err}`))
+        const message = topic
+          ? `Failed to find peers subscribed to ${topic}: ${err}`
+          : `Failed to find peers: ${err}`
+
+        return reply(new Error(message))
       }
 
       reply({Strings: peers})

test/http-api/spec/pubsub.js

@@ -91,13 +91,13 @@ module.exports = (http) => {
     })
 
     describe('/peers', () => {
-      it('returns 500 if no topic is provided', (done) => {
+      it('returns 200 if no topic is provided', (done) => {
         api.inject({
           method: 'GET',
           url: `/api/v0/pubsub/peers`
         }, (res) => {
-          expect(res.statusCode).to.equal(500)
-          expect(res.result.Code).to.be.eql(1)
+          expect(res.statusCode).to.equal(200)
+          expect(res.result.Strings).to.be.eql([])
           done()
         })
       })