From 1451fcb040d26c5f6ae51a13d7382c34db45ab8e Mon Sep 17 00:00:00 2001
From: David Baker <dave@matrix.org>
Date: Wed, 29 Apr 2020 17:01:50 +0100
Subject: [PATCH] Add initialFetch param to willUpdateDevices / devicesUpdated

This indicates whether the device database is being populated initially
---
 src/client.js            | 4 ++++
 src/crypto/DeviceList.js | 9 +++++++--
 2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/src/client.js b/src/client.js
index cad322be1..6ae309616 100644
--- a/src/client.js
+++ b/src/client.js
@@ -5593,12 +5593,16 @@ MatrixClient.prototype.generateClientSecret = function() {
  * Fires whenever the stored devices for a user have changed
  * @event module:client~MatrixClient#"crypto.devicesUpdated"
  * @param {String[]} users A list of user IDs that were updated
+ * @param {bool} initialFetch If true, the store was empty (apart
+ *     from our own device) and has been seeded.
  */
 
 /**
  * Fires whenever the stored devices for a user will be updated
  * @event module:client~MatrixClient#"crypto.willUpdateDevices"
  * @param {String[]} users A list of user IDs that will be updated
+ * @param {bool} initialFetch If true, the store is empty (apart
+ *     from our own device) and is being seeded.
  */
 
 /**
diff --git a/src/crypto/DeviceList.js b/src/crypto/DeviceList.js
index aeb3a4487..5925f8adb 100644
--- a/src/crypto/DeviceList.js
+++ b/src/crypto/DeviceList.js
@@ -109,6 +109,9 @@ export class DeviceList extends EventEmitter {
         this._savePromiseTime = null;
         // The timer used to delay the save
         this._saveTimer = null;
+        // True if we have fetched data from the server or loaded a non-empty
+        // set of device data from the store
+        this._hasFetched = null;
     }
 
     /**
@@ -118,6 +121,7 @@ export class DeviceList extends EventEmitter {
         await this._cryptoStore.doTxn(
             'readonly', [IndexedDBCryptoStore.STORE_DEVICE_DATA], (txn) => {
                 this._cryptoStore.getEndToEndDeviceData(txn, (deviceData) => {
+                    this._hasFetched = Boolean(deviceData && deviceData.devices);
                     this._devices = deviceData ? deviceData.devices : {},
                     this._crossSigningInfo = deviceData ?
                         deviceData.crossSigningInfo || {} : {};
@@ -652,7 +656,7 @@ export class DeviceList extends EventEmitter {
         });
 
         const finished = (success) => {
-            this.emit("crypto.willUpdateDevices", users);
+            this.emit("crypto.willUpdateDevices", users, !this._hasFetched);
             users.forEach((u) => {
                 this._dirty = true;
 
@@ -678,7 +682,8 @@ export class DeviceList extends EventEmitter {
                 }
             });
             this.saveIfDirty();
-            this.emit("crypto.devicesUpdated", users);
+            this.emit("crypto.devicesUpdated", users, !this._hasFetched);
+            this._hasFetched = true;
         };
 
         return prom;