Add a getAllEndToEndSessions to crypto store

src/crypto/store/indexeddb-crypto-store-backend.js

@@ -384,6 +384,24 @@ export class Backend {
         };
     }
 
+    getAllEndToEndSessions(txn, func) {
+        const objectStore = txn.objectStore("sessions");
+        const getReq = objectStore.openCursor();
+        getReq.onsuccess = function() {
+            const cursor = getReq.result;
+            if (cursor) {
+                func(cursor.value);
+                cursor.continue();
+            } else {
+                try {
+                    func(null);
+                } catch (e) {
+                    abortWithException(txn, e);
+                }
+            }
+        };
+    }
+
     storeEndToEndSession(deviceKey, sessionId, sessionInfo, txn) {
         const objectStore = txn.objectStore("sessions");
         objectStore.put({

src/crypto/store/indexeddb-crypto-store.js

@@ -336,6 +336,17 @@ export default class IndexedDBCryptoStore {
         this._backendPromise.value().getEndToEndSessions(deviceKey, txn, func);
     }
 
+    /**
+     * Retrieve all end-to-end sessions
+     * @param {*} txn An active transaction. See doTxn().
+     * @param {function(object)} func Called one for each session with
+     *     an object with, deviceKey, lastReceivedMessageTs, sessionId
+     *     and session keys.
+     */
+    getAllEndToEndSessions(txn, func) {
+        this._backendPromise.value().getAllEndToEndSessions(txn, func);
+    }
+
     /**
      * Store a session between the logged-in user and another device
      * @param {string} deviceKey The public key of the other device.

src/crypto/store/localStorage-crypto-store.js

@@ -94,6 +94,17 @@ export default class LocalStorageCryptoStore extends MemoryCryptoStore {
         func(this._getEndToEndSessions(deviceKey) || {});
     }
 
+    getAllEndToEndSessions(txn, func) {
+        for (let i = 0; i < this.store.length; ++i) {
+            if (this.store.key(i).startsWith(keyEndToEndSessions(''))) {
+                const deviceKey = this.store.key(i).split('/')[1];
+                for (const sess of Object.values(this._getEndToEndSessions(deviceKey))) {
+                    func(sess);
+                }
+            }
+        }
+    }
+
     storeEndToEndSession(deviceKey, sessionId, sessionInfo, txn) {
         const sessions = this._getEndToEndSessions(deviceKey) || {};
         sessions[sessionId] = sessionInfo;

src/crypto/store/memory-crypto-store.js

@@ -249,6 +249,14 @@ export default class MemoryCryptoStore {
         func(this._sessions[deviceKey] || {});
     }
 
+    getAllEndToEndSessions(txn, func) {
+        for (const deviceSessions of Object.values(this._sessions)) {
+            for (const sess of Object.values(deviceSessions)) {
+                func(sess);
+            }
+        }
+    }
+
     storeEndToEndSession(deviceKey, sessionId, sessionInfo, txn) {
         let deviceSessions = this._sessions[deviceKey];
         if (deviceSessions === undefined) {