From 2546e23a3e63b312c721bee9a82f3d68d548a938 Mon Sep 17 00:00:00 2001
From: David Baker <dave@matrix.org>
Date: Mon, 20 Apr 2020 14:36:15 +0100
Subject: [PATCH] Don't recheck DeviceListener until after initial sync is
 finished

Each recheck caused a GET to account data to see if the master key
exists if done before the initial sync, which is unnecessary here.
This just makes it wait until the initial sync is done to recheck.

Fixes https://github.com/vector-im/riot-web/issues/13279
---
 src/DeviceListener.js | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/src/DeviceListener.js b/src/DeviceListener.js
index 3201e4af45..4ec2ec0fa0 100644
--- a/src/DeviceListener.js
+++ b/src/DeviceListener.js
@@ -52,6 +52,7 @@ export default class DeviceListener {
         MatrixClientPeg.get().on('userTrustStatusChanged', this._onUserTrustStatusChanged);
         MatrixClientPeg.get().on('crossSigning.keysChanged', this._onCrossSingingKeysChanged);
         MatrixClientPeg.get().on('accountData', this._onAccountData);
+        MatrixClientPeg.get().on('sync', this._onSync);
         this._recheck();
     }
 
@@ -62,6 +63,7 @@ export default class DeviceListener {
             MatrixClientPeg.get().removeListener('userTrustStatusChanged', this._onUserTrustStatusChanged);
             MatrixClientPeg.get().removeListener('crossSigning.keysChanged', this._onCrossSingingKeysChanged);
             MatrixClientPeg.get().removeListener('accountData', this._onAccountData);
+            MatrixClientPeg.get().removeListener('sync', this._onSync);
         }
         this._dismissed.clear();
     }
@@ -109,6 +111,10 @@ export default class DeviceListener {
         }
     }
 
+    _onSync = (state, prevState) => {
+        if (state === 'PREPARED' && prevState === null) this._recheck();
+    }
+
     // The server doesn't tell us when key backup is set up, so we poll
     // & cache the result
     async _getKeyBackupInfo() {
@@ -129,6 +135,10 @@ export default class DeviceListener {
         ) return;
 
         if (!cli.isCryptoEnabled()) return;
+        // don't recheck until the initial sync is complete: lots of account data events will fire
+        // while the initial sync is processing and we don't need to recheck on each one of them
+        // (we add a listener on sync to do once check after the initial sync is done)
+        if (!cli.isInitialSyncComplete()) return;
 
         const crossSigningReady = await cli.isCrossSigningReady();