Handle too many validators properly (#151)

* Revert debug flag
* Remove dead code
* Disallow subscribing if too many validators

packages/backend/src/Aggregator.ts

@@ -47,23 +47,6 @@ export default class Aggregator {
       }
     });
 
-    feed.events.on('subscribe-consensus-info', (label: Types.ChainLabel) => {
-      const chain = this.chains.get(label);
-
-      if (chain) {
-        feed.sendMessage(Feed.subscribedTo(label));
-        chain.addFeed(feed);
-      }
-    });
-
-    feed.events.on('unsubscribe-consensus-info', (label: Types.ChainLabel) => {
-      const chain = this.chains.get(label);
-
-      if (chain) {
-        chain.removeFeed(feed);
-        feed.sendMessage(Feed.unsubscribedFrom(label));
-      }
-    });
   }
 
   public getExistingChain(label: Types.ChainLabel) : Maybe<Chain> {

packages/frontend/src/AfgHandling.ts

@@ -1,6 +1,7 @@
 import { Types } from '@dotstats/common';
 import { State, UpdateBound } from './state';
 
+// Number of blocks which are kept in memory
 const BLOCKS_LIMIT = 50;
 
 export class AfgHandling {

packages/frontend/src/Connection.ts

@@ -3,6 +3,7 @@ import { State, Update, Node, UpdateBound } from './state';
 import { PersistentSet } from './persist';
 import { getHashData, setHashData } from './utils';
 import { AfgHandling } from './AfgHandling';
+import { VIS_AUTHORITIES_LIMIT } from '../../frontend/src/components/Consensus';
 
 const { Actions } = FeedMessage;
 
@@ -14,13 +15,11 @@ export class Connection {
     return new Connection(await Connection.socket(), update, pins);
   }
 
-  private static readonly debug: number = 2;
-
-  private static readonly address1 = window.location.protocol === 'https:'
+  private static readonly address = window.location.protocol === 'https:'
                                       ? `wss://${window.location.hostname}/feed/`
                                       : `ws://${window.location.hostname}:8080`;
 
-  private static readonly address2 = 'wss://telemetry.polkadot.io/feed/';
+  // private static readonly address = 'wss://telemetry.polkadot.io/feed/';
 
   private static async socket(): Promise<WebSocket> {
     let socket = await Connection.trySocket();
@@ -54,7 +53,7 @@ export class Connection {
         resolve(null);
       }
 
-      const socket = new WebSocket(Connection.debug === 1 ? Connection.address1 : Connection.address2);
+      const socket = new WebSocket(Connection.address);
 
       socket.addEventListener('open', onSuccess);
       socket.addEventListener('error', onFailure);
@@ -93,9 +92,11 @@ export class Connection {
   }
 
   public subscribeConsensus(chain: Types.ChainLabel) {
-    setHashData({ chain });
-    this.resubscribeSendFinality = true;
-    this.socket.send(`send-finality:${chain}`);
+    if (this.state.authorities.length <= VIS_AUTHORITIES_LIMIT) {
+      setHashData({chain});
+      this.resubscribeSendFinality = true;
+      this.socket.send(`send-finality:${chain}`);
+    }
   }
 
   public resetConsensus() {

packages/frontend/src/components/Consensus/Consensus.tsx

@@ -8,7 +8,9 @@ import { State as AppState } from '../../state';
 
 import './Consensus.css';
 
-const AUTHORITIES_LIMIT = 10;
+// Maximum number of authorities the visualization is
+// allowed of processing.
+export const VIS_AUTHORITIES_LIMIT = 10;
 
 export namespace Consensus {
   export interface Props {
@@ -165,13 +167,13 @@ export class Consensus extends React.Component<Consensus.Props, {}> {
     this.state.lastConsensusInfo = JSON.stringify(this.props.appState.consensusInfo);
     const lastBlocks = this.props.appState.consensusInfo;
 
-    if (this.props.appState.authorities.length > AUTHORITIES_LIMIT) {
+    if (this.props.appState.authorities.length > VIS_AUTHORITIES_LIMIT) {
       return <div className="Consensus">
         <div className="tooManyAuthorities">
           <p>
             Too many authorities.</p>
           <p>
-            Won't display for more than {AUTHORITIES_LIMIT} authorities
+            Won't display for more than {VIS_AUTHORITIES_LIMIT} authorities
             to protect your browser.
           </p>
         </div>;