From 7fc3a75bea2c5b0b1352c9ce33c0ecae661dccab Mon Sep 17 00:00:00 2001
From: Lawrence Forooghian <lawrence@forooghian.com>
Date: Thu, 17 Aug 2023 16:45:08 -0300
Subject: [PATCH] Make MessagePack functionality tree-shakable

We move the MessagePack functionality into a tree-shakable MsgPack
module.

Resolves #1375.
---
 scripts/moduleReport.js                       |  2 +-
 src/common/lib/client/baseclient.ts           |  6 +-
 src/common/lib/client/defaultrealtime.ts      | 10 ++-
 src/common/lib/client/defaultrest.ts          | 14 +++-
 src/common/lib/client/modulesmap.ts           |  2 +
 src/common/lib/client/resource.ts             |  5 +-
 src/common/lib/client/rest.ts                 | 16 +++--
 src/common/lib/types/devicedetails.ts         |  2 +-
 src/common/lib/types/message.ts               |  2 +-
 src/common/lib/types/presencemessage.ts       |  2 +-
 .../lib/types/pushchannelsubscription.ts      |  2 +-
 src/common/lib/util/defaults.ts               | 15 ++--
 src/common/lib/util/utils.ts                  | 22 ++++--
 src/common/types/IPlatformConfig.d.ts         |  3 -
 src/platform/nativescript/config.js           |  2 -
 src/platform/nativescript/index.ts            |  1 +
 src/platform/nodejs/config.ts                 |  1 -
 src/platform/nodejs/index.ts                  |  2 +
 src/platform/nodejs/lib/util/http.ts          |  6 +-
 src/platform/react-native/config.ts           |  2 -
 src/platform/react-native/index.ts            |  1 +
 src/platform/web-noencryption/index.ts        |  4 ++
 src/platform/web/config.ts                    |  2 -
 src/platform/web/index.ts                     |  1 +
 src/platform/web/modules.ts                   |  1 +
 src/platform/web/modules/msgpack.ts           |  1 +
 test/browser/modules.test.js                  | 71 +++++++++++++++++++
 test/rest/defaults.test.js                    | 22 ++++++
 28 files changed, 183 insertions(+), 37 deletions(-)
 create mode 100644 src/platform/web/modules/msgpack.ts

diff --git a/scripts/moduleReport.js b/scripts/moduleReport.js
index 1937afc34d..577371359f 100644
--- a/scripts/moduleReport.js
+++ b/scripts/moduleReport.js
@@ -1,7 +1,7 @@
 const esbuild = require('esbuild');
 
 // List of all modules accepted in ModulesMap
-const moduleNames = ['Rest', 'Crypto'];
+const moduleNames = ['Rest', 'Crypto', 'MsgPack'];
 
 // List of all free-standing functions exported by the library along with the
 // ModulesMap entries that we expect them to transitively import
diff --git a/src/common/lib/client/baseclient.ts b/src/common/lib/client/baseclient.ts
index 8d8b201036..fcdab7cdd5 100644
--- a/src/common/lib/client/baseclient.ts
+++ b/src/common/lib/client/baseclient.ts
@@ -14,6 +14,7 @@ import { ModulesMap } from './modulesmap';
 import { Rest } from './rest';
 import { IUntypedCryptoStatic } from 'common/types/ICryptoStatic';
 import { throwMissingModuleError } from '../util/utils';
+import { MsgPack } from 'common/types/msgpack';
 
 /**
  `BaseClient` acts as the base class for all of the client classes exported by the SDK. It is an implementation detail and this class is not advertised publicly.
@@ -30,7 +31,7 @@ class BaseClient {
 
   private readonly _rest: Rest | null;
   readonly _Crypto: IUntypedCryptoStatic | null;
-  readonly _MsgPack = Platform.Config.msgpack;
+  readonly _MsgPack: MsgPack | null;
 
   constructor(options: ClientOptions | string, modules: ModulesMap) {
     if (!options) {
@@ -47,7 +48,8 @@ class BaseClient {
       'initialized with clientOptions ' + Platform.Config.inspect(options)
     );
 
-    const normalOptions = (this.options = Defaults.normaliseOptions(optionsObj));
+    this._MsgPack = modules.MsgPack ?? null;
+    const normalOptions = (this.options = Defaults.normaliseOptions(optionsObj, this._MsgPack));
 
     /* process options */
     if (normalOptions.key) {
diff --git a/src/common/lib/client/defaultrealtime.ts b/src/common/lib/client/defaultrealtime.ts
index e8b66f878e..8a905b449d 100644
--- a/src/common/lib/client/defaultrealtime.ts
+++ b/src/common/lib/client/defaultrealtime.ts
@@ -6,13 +6,19 @@ import ConnectionManager from '../transport/connectionmanager';
 import ProtocolMessage from '../types/protocolmessage';
 import Platform from 'common/platform';
 import { DefaultMessage } from '../types/defaultmessage';
+import { MsgPack } from 'common/types/msgpack';
 
 /**
  `DefaultRealtime` is the class that the non tree-shakable version of the SDK exports as `Realtime`. It ensures that this version of the SDK includes all of the functionality which is optionally available in the tree-shakable version.
  */
 export class DefaultRealtime extends BaseRealtime {
   constructor(options: ClientOptions) {
-    super(options, { ...allCommonModules, Crypto: DefaultRealtime.Crypto ?? undefined });
+    const MsgPack = DefaultRealtime._MsgPack;
+    if (!MsgPack) {
+      throw new Error('Expected DefaultRealtime._MsgPack to have been set');
+    }
+
+    super(options, { ...allCommonModules, Crypto: DefaultRealtime.Crypto ?? undefined, MsgPack });
   }
 
   static Utils = Utils;
@@ -32,4 +38,6 @@ export class DefaultRealtime extends BaseRealtime {
   }
 
   static Message = DefaultMessage;
+
+  static _MsgPack: MsgPack | null = null;
 }
diff --git a/src/common/lib/client/defaultrest.ts b/src/common/lib/client/defaultrest.ts
index 1b7df607a6..e70a9eecf6 100644
--- a/src/common/lib/client/defaultrest.ts
+++ b/src/common/lib/client/defaultrest.ts
@@ -3,13 +3,23 @@ import ClientOptions from '../../types/ClientOptions';
 import { allCommonModules } from './modulesmap';
 import Platform from 'common/platform';
 import { DefaultMessage } from '../types/defaultmessage';
+import { MsgPack } from 'common/types/msgpack';
 
 /**
  `DefaultRest` is the class that the non tree-shakable version of the SDK exports as `Rest`. It ensures that this version of the SDK includes all of the functionality which is optionally available in the tree-shakable version.
  */
 export class DefaultRest extends BaseRest {
   constructor(options: ClientOptions | string) {
-    super(options, { ...allCommonModules, Crypto: DefaultRest.Crypto ?? undefined });
+    const MsgPack = DefaultRest._MsgPack;
+    if (!MsgPack) {
+      throw new Error('Expected DefaultRest._MsgPack to have been set');
+    }
+
+    super(options, {
+      ...allCommonModules,
+      Crypto: DefaultRest.Crypto ?? undefined,
+      MsgPack: DefaultRest._MsgPack ?? undefined,
+    });
   }
 
   private static _Crypto: typeof Platform.Crypto = null;
@@ -25,4 +35,6 @@ export class DefaultRest extends BaseRest {
   }
 
   static Message = DefaultMessage;
+
+  static _MsgPack: MsgPack | null = null;
 }
diff --git a/src/common/lib/client/modulesmap.ts b/src/common/lib/client/modulesmap.ts
index 4133bcc3a3..12ac9bc7f6 100644
--- a/src/common/lib/client/modulesmap.ts
+++ b/src/common/lib/client/modulesmap.ts
@@ -1,9 +1,11 @@
 import { Rest } from './rest';
 import { IUntypedCryptoStatic } from '../../types/ICryptoStatic';
+import { MsgPack } from 'common/types/msgpack';
 
 export interface ModulesMap {
   Rest?: typeof Rest;
   Crypto?: IUntypedCryptoStatic;
+  MsgPack?: MsgPack;
 }
 
 export const allCommonModules: ModulesMap = { Rest };
diff --git a/src/common/lib/client/resource.ts b/src/common/lib/client/resource.ts
index 8a1b855369..7d506d369e 100644
--- a/src/common/lib/client/resource.ts
+++ b/src/common/lib/client/resource.ts
@@ -30,7 +30,7 @@ function withAuthDetails(
 
 function unenvelope<T>(
   callback: ResourceCallback<T>,
-  MsgPack: MsgPack,
+  MsgPack: MsgPack | null,
   format: Utils.Format | null
 ): ResourceCallback<T> {
   return (err, body, outerHeaders, unpacked, outerStatusCode) => {
@@ -226,6 +226,9 @@ class Resource {
         let decodedBody = body;
         if (headers['content-type']?.indexOf('msgpack') > 0) {
           try {
+            if (!client._MsgPack) {
+              Utils.throwMissingModuleError('MsgPack');
+            }
             decodedBody = client._MsgPack.decode(body as Buffer);
           } catch (decodeErr) {
             Logger.logAction(
diff --git a/src/common/lib/client/rest.ts b/src/common/lib/client/rest.ts
index b4ab2e3124..97c142851e 100644
--- a/src/common/lib/client/rest.ts
+++ b/src/common/lib/client/rest.ts
@@ -113,11 +113,17 @@ export class Rest {
     customHeaders: Record<string, string>,
     callback: StandardCallback<HttpPaginatedResponse<unknown>>
   ): Promise<HttpPaginatedResponse<unknown>> | void {
-    const useBinary = this.client.options.useBinaryProtocol,
-      encoder = useBinary ? this.client._MsgPack.encode : JSON.stringify,
-      decoder = useBinary ? this.client._MsgPack.decode : JSON.parse,
-      format = useBinary ? Utils.Format.msgpack : Utils.Format.json,
-      envelope = this.client.http.supportsLinkHeaders ? undefined : format;
+    const [encoder, decoder, format] = (() => {
+      if (this.client.options.useBinaryProtocol) {
+        if (!this.client._MsgPack) {
+          Utils.throwMissingModuleError('MsgPack');
+        }
+        return [this.client._MsgPack.encode, this.client._MsgPack.decode, Utils.Format.msgpack];
+      } else {
+        return [JSON.stringify, JSON.parse, Utils.Format.json];
+      }
+    })();
+    const envelope = this.client.http.supportsLinkHeaders ? undefined : format;
     params = params || {};
     const _method = method.toLowerCase() as HttpMethods;
     const headers =
diff --git a/src/common/lib/types/devicedetails.ts b/src/common/lib/types/devicedetails.ts
index a8ba6c953c..8ad7e59a0b 100644
--- a/src/common/lib/types/devicedetails.ts
+++ b/src/common/lib/types/devicedetails.ts
@@ -75,7 +75,7 @@ class DeviceDetails {
 
   static fromResponseBody(
     body: Array<Record<string, unknown>> | Record<string, unknown>,
-    MsgPack: MsgPack,
+    MsgPack: MsgPack | null,
     format?: Utils.Format
   ): DeviceDetails | DeviceDetails[] {
     if (format) {
diff --git a/src/common/lib/types/message.ts b/src/common/lib/types/message.ts
index 7a994d867d..48285adae3 100644
--- a/src/common/lib/types/message.ts
+++ b/src/common/lib/types/message.ts
@@ -336,7 +336,7 @@ class Message {
   static async fromResponseBody(
     body: Array<Message>,
     options: ChannelOptions | EncodingDecodingContext,
-    MsgPack: MsgPack,
+    MsgPack: MsgPack | null,
     format?: Utils.Format
   ): Promise<Message[]> {
     if (format) {
diff --git a/src/common/lib/types/presencemessage.ts b/src/common/lib/types/presencemessage.ts
index 01e9e2f786..48b6ef5a1b 100644
--- a/src/common/lib/types/presencemessage.ts
+++ b/src/common/lib/types/presencemessage.ts
@@ -106,7 +106,7 @@ class PresenceMessage {
   static async fromResponseBody(
     body: Record<string, unknown>[],
     options: CipherOptions,
-    MsgPack: MsgPack,
+    MsgPack: MsgPack | null,
     format?: Utils.Format
   ): Promise<PresenceMessage[]> {
     const messages: PresenceMessage[] = [];
diff --git a/src/common/lib/types/pushchannelsubscription.ts b/src/common/lib/types/pushchannelsubscription.ts
index 16a150b1d6..48190f25af 100644
--- a/src/common/lib/types/pushchannelsubscription.ts
+++ b/src/common/lib/types/pushchannelsubscription.ts
@@ -37,7 +37,7 @@ class PushChannelSubscription {
 
   static fromResponseBody(
     body: Array<Record<string, unknown>> | Record<string, unknown>,
-    MsgPack: MsgPack,
+    MsgPack: MsgPack | null,
     format?: Utils.Format
   ): PushChannelSubscription | PushChannelSubscription[] {
     if (format) {
diff --git a/src/common/lib/util/defaults.ts b/src/common/lib/util/defaults.ts
index 4f0ba8ee53..9939c975c7 100644
--- a/src/common/lib/util/defaults.ts
+++ b/src/common/lib/util/defaults.ts
@@ -5,6 +5,7 @@ import ErrorInfo from 'common/lib/types/errorinfo';
 import { version } from '../../../../package.json';
 import ClientOptions, { InternalClientOptions, NormalisedClientOptions } from 'common/types/ClientOptions';
 import IDefaults from '../../types/IDefaults';
+import { MsgPack } from 'common/types/msgpack';
 
 let agent = 'ably-js/' + version;
 
@@ -41,7 +42,7 @@ type CompleteDefaults = IDefaults & {
   checkHost(host: string): void;
   getRealtimeHost(options: ClientOptions, production: boolean, environment: string): string;
   objectifyOptions(options: ClientOptions | string): ClientOptions;
-  normaliseOptions(options: InternalClientOptions): NormalisedClientOptions;
+  normaliseOptions(options: InternalClientOptions, MsgPack: MsgPack | null): NormalisedClientOptions;
   defaultGetHeaders(options: NormalisedClientOptions, headersOptions?: HeadersOptions): Record<string, string>;
   defaultPostHeaders(options: NormalisedClientOptions, headersOptions?: HeadersOptions): Record<string, string>;
 };
@@ -185,7 +186,7 @@ export function objectifyOptions(options: ClientOptions | string): ClientOptions
   return options;
 }
 
-export function normaliseOptions(options: InternalClientOptions): NormalisedClientOptions {
+export function normaliseOptions(options: InternalClientOptions, MsgPack: MsgPack | null): NormalisedClientOptions {
   if (typeof options.recover === 'function' && options.closeOnUnload === true) {
     Logger.logAction(
       Logger.LOG_ERROR,
@@ -222,10 +223,14 @@ export function normaliseOptions(options: InternalClientOptions): NormalisedClie
 
   const timeouts = getTimeouts(options);
 
-  if ('useBinaryProtocol' in options) {
-    options.useBinaryProtocol = Platform.Config.supportsBinary && options.useBinaryProtocol;
+  if (MsgPack) {
+    if ('useBinaryProtocol' in options) {
+      options.useBinaryProtocol = Platform.Config.supportsBinary && options.useBinaryProtocol;
+    } else {
+      options.useBinaryProtocol = Platform.Config.preferBinary;
+    }
   } else {
-    options.useBinaryProtocol = Platform.Config.preferBinary;
+    options.useBinaryProtocol = false;
   }
 
   const headers: Record<string, string> = {};
diff --git a/src/common/lib/util/utils.ts b/src/common/lib/util/utils.ts
index b5d9181e7e..d3aca59d2f 100644
--- a/src/common/lib/util/utils.ts
+++ b/src/common/lib/util/utils.ts
@@ -451,12 +451,26 @@ export function promisify<T>(ob: Record<string, any>, fnName: string, args: IArg
   });
 }
 
-export function decodeBody<T>(body: unknown, MsgPack: MsgPack, format?: Format | null): T {
-  return format == 'msgpack' ? MsgPack.decode(body as Buffer) : JSON.parse(String(body));
+export function decodeBody<T>(body: unknown, MsgPack: MsgPack | null, format?: Format | null): T {
+  if (format == 'msgpack') {
+    if (!MsgPack) {
+      throwMissingModuleError('MsgPack');
+    }
+    return MsgPack.decode(body as Buffer);
+  }
+
+  return JSON.parse(String(body));
 }
 
-export function encodeBody(body: unknown, MsgPack: MsgPack, format?: Format): string | Buffer {
-  return format == 'msgpack' ? (MsgPack.encode(body, true) as Buffer) : JSON.stringify(body);
+export function encodeBody(body: unknown, MsgPack: MsgPack | null, format?: Format): string | Buffer {
+  if (format == 'msgpack') {
+    if (!MsgPack) {
+      throwMissingModuleError('MsgPack');
+    }
+    return MsgPack.encode(body, true) as Buffer;
+  }
+
+  return JSON.stringify(body);
 }
 
 export function allToLowerCase(arr: Array<string>): Array<string> {
diff --git a/src/common/types/IPlatformConfig.d.ts b/src/common/types/IPlatformConfig.d.ts
index 4a83e20a39..9d678f23bb 100644
--- a/src/common/types/IPlatformConfig.d.ts
+++ b/src/common/types/IPlatformConfig.d.ts
@@ -1,12 +1,9 @@
-import { MsgPack } from './msgpack';
-
 export interface IPlatformConfig {
   agent: string;
   logTimestamps: boolean;
   binaryType: BinaryType;
   WebSocket: typeof WebSocket | typeof import('ws');
   useProtocolHeartbeats: boolean;
-  msgpack: MsgPack;
   supportsBinary: boolean;
   preferBinary: boolean;
   nextTick: process.nextTick;
diff --git a/src/platform/nativescript/config.js b/src/platform/nativescript/config.js
index 31090e0240..ccdece4dd5 100644
--- a/src/platform/nativescript/config.js
+++ b/src/platform/nativescript/config.js
@@ -1,5 +1,4 @@
 /* eslint-disable no-undef */
-import msgpack from '../web/lib/util/msgpack';
 require('nativescript-websockets');
 
 var randomBytes;
@@ -28,7 +27,6 @@ var Config = {
   allowComet: true,
   streamingSupported: false,
   useProtocolHeartbeats: true,
-  msgpack: msgpack,
   supportsBinary: typeof TextDecoder !== 'undefined' && TextDecoder,
   preferBinary: false,
   ArrayBuffer: ArrayBuffer,
diff --git a/src/platform/nativescript/index.ts b/src/platform/nativescript/index.ts
index d6f5e133cf..7fc4a1a65a 100644
--- a/src/platform/nativescript/index.ts
+++ b/src/platform/nativescript/index.ts
@@ -30,6 +30,7 @@ Platform.WebStorage = WebStorage;
 
 for (const clientClass of [DefaultRest, DefaultRealtime]) {
   clientClass.Crypto = Crypto;
+  clientClass._MsgPack = msgpack;
 }
 
 Logger.initLogHandlers();
diff --git a/src/platform/nodejs/config.ts b/src/platform/nodejs/config.ts
index 716be3b12a..4947994239 100644
--- a/src/platform/nodejs/config.ts
+++ b/src/platform/nodejs/config.ts
@@ -10,7 +10,6 @@ const Config: IPlatformConfig = {
   binaryType: 'nodebuffer' as BinaryType,
   WebSocket,
   useProtocolHeartbeats: false,
-  msgpack: require('@ably/msgpack-js'),
   supportsBinary: true,
   preferBinary: true,
   nextTick: process.nextTick,
diff --git a/src/platform/nodejs/index.ts b/src/platform/nodejs/index.ts
index 796596f083..6c1756037d 100644
--- a/src/platform/nodejs/index.ts
+++ b/src/platform/nodejs/index.ts
@@ -14,6 +14,7 @@ import Transports from './lib/transport';
 import Logger from '../../common/lib/util/logger';
 import { getDefaults } from '../../common/lib/util/defaults';
 import PlatformDefaults from './lib/util/defaults';
+import msgpack = require('@ably/msgpack-js');
 
 const Crypto = createCryptoClass(BufferUtils);
 
@@ -26,6 +27,7 @@ Platform.WebStorage = null;
 
 for (const clientClass of [DefaultRest, DefaultRealtime]) {
   clientClass.Crypto = Crypto;
+  clientClass._MsgPack = msgpack;
 }
 
 Logger.initLogHandlers();
diff --git a/src/platform/nodejs/lib/util/http.ts b/src/platform/nodejs/lib/util/http.ts
index ff5b2868e9..50c38fd5ce 100644
--- a/src/platform/nodejs/lib/util/http.ts
+++ b/src/platform/nodejs/lib/util/http.ts
@@ -10,7 +10,7 @@ import BaseClient from 'common/lib/client/baseclient';
 import BaseRealtime from 'common/lib/client/baserealtime';
 import { NormalisedClientOptions, RestAgentOptions } from 'common/types/ClientOptions';
 import { isSuccessCode } from 'common/constants/HttpStatusCodes';
-import { shallowEquals } from 'common/lib/util/utils';
+import { shallowEquals, throwMissingModuleError } from 'common/lib/util/utils';
 
 /***************************************************
  *
@@ -42,8 +42,8 @@ const handler = function (uri: string, params: unknown, client: BaseClient | nul
           body = JSON.parse(body as string);
           break;
         case 'application/x-msgpack':
-          if (!client) {
-            throw new ErrorInfo('Cannot use MessagePack without a client', 400, 40000);
+          if (!client?._MsgPack) {
+            throwMissingModuleError('MsgPack');
           }
           body = client._MsgPack.decode(body as Buffer);
       }
diff --git a/src/platform/react-native/config.ts b/src/platform/react-native/config.ts
index f6e6f29a2e..6a2f0107b8 100644
--- a/src/platform/react-native/config.ts
+++ b/src/platform/react-native/config.ts
@@ -1,4 +1,3 @@
-import msgpack from '../web/lib/util/msgpack';
 import { IPlatformConfig } from '../../common/types/IPlatformConfig';
 import BufferUtils from '../web/lib/util/bufferutils';
 
@@ -13,7 +12,6 @@ export default function (bufferUtils: typeof BufferUtils): IPlatformConfig {
     allowComet: true,
     streamingSupported: true,
     useProtocolHeartbeats: true,
-    msgpack: msgpack,
     supportsBinary: !!(typeof TextDecoder !== 'undefined' && TextDecoder),
     preferBinary: false,
     ArrayBuffer: typeof ArrayBuffer !== 'undefined' && ArrayBuffer,
diff --git a/src/platform/react-native/index.ts b/src/platform/react-native/index.ts
index 88158e1bb8..b02dc5d50a 100644
--- a/src/platform/react-native/index.ts
+++ b/src/platform/react-native/index.ts
@@ -30,6 +30,7 @@ Platform.WebStorage = WebStorage;
 
 for (const clientClass of [DefaultRest, DefaultRealtime]) {
   clientClass.Crypto = Crypto;
+  clientClass._MsgPack = msgpack;
 }
 
 Logger.initLogHandlers();
diff --git a/src/platform/web-noencryption/index.ts b/src/platform/web-noencryption/index.ts
index 2d04d683a7..2fb7d858e6 100644
--- a/src/platform/web-noencryption/index.ts
+++ b/src/platform/web-noencryption/index.ts
@@ -23,6 +23,10 @@ Platform.Config = Config;
 Platform.Transports = Transports;
 Platform.WebStorage = WebStorage;
 
+for (const clientClass of [DefaultRest, DefaultRealtime]) {
+  clientClass._MsgPack = msgpack;
+}
+
 Logger.initLogHandlers();
 
 Platform.Defaults = getDefaults(PlatformDefaults);
diff --git a/src/platform/web/config.ts b/src/platform/web/config.ts
index 87536361ad..f3aac12c93 100644
--- a/src/platform/web/config.ts
+++ b/src/platform/web/config.ts
@@ -1,4 +1,3 @@
-import msgpack from './lib/util/msgpack';
 import { IPlatformConfig } from '../../common/types/IPlatformConfig';
 import * as Utils from 'common/lib/util/utils';
 
@@ -37,7 +36,6 @@ const Config: IPlatformConfig = {
   allowComet: allowComet(),
   streamingSupported: true,
   useProtocolHeartbeats: true,
-  msgpack: msgpack,
   supportsBinary: !!globalObject.TextDecoder,
   preferBinary: false,
   ArrayBuffer: globalObject.ArrayBuffer,
diff --git a/src/platform/web/index.ts b/src/platform/web/index.ts
index e1c1831c39..d3c3184420 100644
--- a/src/platform/web/index.ts
+++ b/src/platform/web/index.ts
@@ -28,6 +28,7 @@ Platform.WebStorage = WebStorage;
 
 for (const clientClass of [DefaultRest, DefaultRealtime]) {
   clientClass.Crypto = Crypto;
+  clientClass._MsgPack = msgpack;
 }
 
 Logger.initLogHandlers();
diff --git a/src/platform/web/modules.ts b/src/platform/web/modules.ts
index 06d4d692de..bb701d1fdd 100644
--- a/src/platform/web/modules.ts
+++ b/src/platform/web/modules.ts
@@ -40,5 +40,6 @@ if (Platform.Config.noUpgrade) {
 
 export * from './modules/crypto';
 export * from './modules/message';
+export * from './modules/msgpack';
 export { Rest } from '../../common/lib/client/rest';
 export { BaseRest, BaseRealtime };
diff --git a/src/platform/web/modules/msgpack.ts b/src/platform/web/modules/msgpack.ts
new file mode 100644
index 0000000000..698b09e34c
--- /dev/null
+++ b/src/platform/web/modules/msgpack.ts
@@ -0,0 +1 @@
+export { default as MsgPack } from '../lib/util/msgpack';
diff --git a/test/browser/modules.test.js b/test/browser/modules.test.js
index 5b9332fdcf..f96840a55d 100644
--- a/test/browser/modules.test.js
+++ b/test/browser/modules.test.js
@@ -9,6 +9,7 @@ import {
   decodeMessages,
   decodeEncryptedMessages,
   Crypto,
+  MsgPack,
 } from '../../build/modules/index.js';
 
 describe('browser/modules', function () {
@@ -244,4 +245,74 @@ describe('browser/modules', function () {
       }
     });
   });
+
+  describe('MsgPack', () => {
+    async function testRestUsesContentType(rest, expectedContentType) {
+      const channelName = 'channel';
+      const channel = rest.channels.get(channelName);
+      const contentTypeUsedForPublishPromise = new Promise((resolve, reject) => {
+        rest.http.do = (method, client, path, headers, body, params, callback) => {
+          if (!(method == 'post' && path == `/channels/${channelName}/messages`)) {
+            return;
+          }
+          resolve(headers['content-type']);
+          callback(null);
+        };
+      });
+
+      await channel.publish('message', 'body');
+
+      const contentTypeUsedForPublish = await contentTypeUsedForPublishPromise;
+      expect(contentTypeUsedForPublish).to.equal(expectedContentType);
+    }
+
+    async function testRealtimeUsesFormat(realtime, expectedFormat) {
+      const formatUsedForConnectionPromise = new Promise((resolve, reject) => {
+        realtime.connection.connectionManager.connectImpl = (transportParams) => {
+          resolve(transportParams.format);
+        };
+      });
+      realtime.connect();
+
+      const formatUsedForConnection = await formatUsedForConnectionPromise;
+      expect(formatUsedForConnection).to.equal(expectedFormat);
+    }
+
+    // TODO once https://github.com/ably/ably-js/issues/1424 is fixed, this should also test the case where the useBinaryProtocol option is not specified
+    describe('with useBinaryProtocol client option', () => {
+      describe('without MsgPack', () => {
+        describe('BaseRest', () => {
+          it('uses JSON', async () => {
+            const client = new BaseRest(ablyClientOptions({ useBinaryProtocol: true }), {});
+            await testRestUsesContentType(client, 'application/json');
+          });
+        });
+
+        describe('BaseRealtime', () => {
+          it('uses JSON', async () => {
+            const client = new BaseRealtime(ablyClientOptions({ useBinaryProtocol: true, autoConnect: false }), {});
+            await testRealtimeUsesFormat(client, 'json');
+          });
+        });
+      });
+
+      describe('with MsgPack', () => {
+        describe('BaseRest', () => {
+          it('uses MessagePack', async () => {
+            const client = new BaseRest(ablyClientOptions({ useBinaryProtocol: true }), { MsgPack });
+            await testRestUsesContentType(client, 'application/x-msgpack');
+          });
+        });
+
+        describe('BaseRealtime', () => {
+          it('uses MessagePack', async () => {
+            const client = new BaseRealtime(ablyClientOptions({ useBinaryProtocol: true, autoConnect: false }), {
+              MsgPack,
+            });
+            await testRealtimeUsesFormat(client, 'msgpack');
+          });
+        });
+      });
+    });
+  });
 });
diff --git a/test/rest/defaults.test.js b/test/rest/defaults.test.js
index 40be2e7213..173dfd684e 100644
--- a/test/rest/defaults.test.js
+++ b/test/rest/defaults.test.js
@@ -135,6 +135,28 @@ define(['ably', 'chai'], function (Ably, chai) {
       Defaults.ENVIRONMENT = '';
     });
 
+    // TODO once https://github.com/ably/ably-js/issues/1424 is fixed, this should also test the case where the useBinaryProtocol option is not specified
+    describe('normaliseOptions with useBinaryProtocol == true', () => {
+      if (Ably.Realtime.Platform.Config.supportsBinary) {
+        describe('given MsgPack implementation', () => {
+          it('maintains useBinaryProtocol as true', () => {
+            const StubMsgPack = {};
+            var normalisedOptions = Defaults.normaliseOptions({ useBinaryProtocol: true }, StubMsgPack);
+
+            expect(normalisedOptions.useBinaryProtocol).to.be.true;
+          });
+        });
+      }
+
+      describe('given no MsgPack implementation', () => {
+        it('changes useBinaryProtocol to false', () => {
+          var normalisedOptions = Defaults.normaliseOptions({ useBinaryProtocol: true }, null);
+
+          expect(normalisedOptions.useBinaryProtocol).to.be.false;
+        });
+      });
+    });
+
     it('closeOnUnload', function () {
       var options;