Test that we can decrypt history messages

test/browser/modular.test.js

@@ -507,6 +507,39 @@ function registerAblyModularTests(Helper) {
           );
         }
 
+        async function testIsAbleToDecryptHistoryMessages(helper, clientClassConfig) {
+          const clientOptions = helper.ablyClientOptions();
+
+          const client = new clientClassConfig.clientClass({
+            ...clientOptions,
+            plugins: {
+              ...clientClassConfig.additionalPlugins,
+              FetchRequest,
+              Crypto,
+            },
+          });
+
+          await (clientClassConfig.isRealtime ? monitorConnectionThenCloseAndFinish : async (helper, op) => await op())(
+            helper,
+            async () => {
+              const channelName = 'encrypted_history',
+                messageText = 'Test message';
+
+              const key = await generateRandomKey();
+
+              const channel = client.channels.get(channelName, { cipher: { key: key } });
+              await channel.publish('event0', messageText);
+              let items;
+              await helper.waitFor(async () => {
+                items = (await channel.history()).items;
+                return items.length > 0;
+              }, 10_000);
+              expect(items[0].data).to.equal(messageText);
+            },
+            client,
+          );
+        }
+
         for (const clientClassConfig of [
           { clientClass: BaseRest, isRealtime: false },
           {
@@ -522,6 +555,22 @@ function registerAblyModularTests(Helper) {
             });
           });
         }
+
+        for (const clientClassConfig of [
+          { clientClass: BaseRest, isRealtime: false },
+          {
+            clientClass: BaseRealtime,
+            additionalPlugins: { WebSocketTransport, Rest },
+            isRealtime: true,
+          },
+        ]) {
+          describe(clientClassConfig.clientClass.name, () => {
+            /** @nospec */
+            it('is able to decrypt history messages', async function () {
+              await testIsAbleToDecryptHistoryMessages(this.test.helper, clientClassConfig);
+            });
+          });
+        }
       });
     });
 

test/common/modules/shared_helper.js

@@ -483,6 +483,15 @@ define([
     dumpPrivateApiUsage() {
       privateApiRecorder.dump();
     }
+
+    async waitFor(condition, remaining) {
+      const success = await condition();
+      if (success || remaining <= 0) {
+        return success;
+      }
+      await this.setTimeoutAsync(100);
+      return this.waitFor(condition, remaining - 100);
+    }
   }
 
   SharedHelper.testOnAllTransports.skip = function (thisInDescribe, name, testFn) {

test/realtime/crypto.test.js

@@ -773,6 +773,31 @@ define(['ably', 'shared_helper', 'async', 'chai'], function (Ably, Helper, async
       });
     });
 
+    /**
+     * @spec RSL5a
+     */
+    it('encrypted history', async function () {
+      if (!Crypto) {
+        done(new Error('Encryption not supported'));
+        return;
+      }
+
+      const helper = this.test.helper,
+        rest = helper.AblyRest(),
+        channelName = 'encrypted_history',
+        messageText = 'Test message';
+
+      const key = await Crypto.generateRandomKey();
+      const channel = rest.channels.get(channelName, { cipher: { key: key } });
+      await channel.publish('event0', messageText);
+      let items;
+      await helper.waitFor(async () => {
+        items = (await channel.history()).items;
+        return items.length > 0;
+      }, 10_000);
+      expect(items[0].data).to.equal(messageText);
+    });
+
     /**
      * Connect twice to the service, using different cipher keys.
      * Publish an encrypted message on that channel using