Decouple Platform.Transport’s transport order from implementations

Preparation for #1394 (making transports tree-shakable).

Author: lawrence-forooghian

src/common/lib/transport/connectionmanager.ts

@@ -410,7 +410,8 @@ class ConnectionManager extends EventEmitter {
 
   static initTransports() {
     WebSocketTransport(ConnectionManager);
-    Utils.arrForEach(Platform.Transports, function (initFn) {
+    Utils.arrForEach(Platform.Transports.order, function (transportName) {
+      const initFn = Platform.Transports.implementations[transportName]!;
       initFn(ConnectionManager);
     });
   }

src/common/platform.ts

@@ -7,11 +7,14 @@ import IBufferUtils from './types/IBufferUtils';
 import * as WebBufferUtils from '../platform/web/lib/util/bufferutils';
 import * as NodeBufferUtils from '../platform/nodejs/lib/util/bufferutils';
 import { IUntypedCryptoStatic } from '../common/types/ICryptoStatic';
+import TransportName from './constants/TransportName';
 
 type Bufferlike = WebBufferUtils.Bufferlike | NodeBufferUtils.Bufferlike;
 type BufferUtilsOutput = WebBufferUtils.Output | NodeBufferUtils.Output;
 type ToBufferOutput = WebBufferUtils.ToBufferOutput | NodeBufferUtils.ToBufferOutput;
 
+export type TransportImplementations = Partial<Record<TransportName, TransportInitialiser>>;
+
 export default class Platform {
   static Config: IPlatformConfig;
   /*
@@ -29,7 +32,10 @@ export default class Platform {
    */
   static Crypto: IUntypedCryptoStatic | null;
   static Http: typeof IHttp;
-  static Transports: TransportInitialiser[];
+  static Transports: {
+    order: TransportName[];
+    implementations: TransportImplementations;
+  };
   static Defaults: IDefaults;
   static WebStorage: IWebStorage | null;
 }

src/platform/nodejs/lib/transport/index.ts

@@ -1,3 +1,7 @@
+import TransportName from 'common/constants/TransportName';
 import initialiseNodeCometTransport from './nodecomettransport';
 
-export default [initialiseNodeCometTransport];
+export default {
+  order: [TransportName.Comet],
+  implementations: { [TransportName.Comet]: initialiseNodeCometTransport },
+};

src/platform/web/lib/transport/index.ts

@@ -1,4 +1,11 @@
+import TransportName from 'common/constants/TransportName';
 import initialiseXHRPollingTransport from './xhrpollingtransport';
 import initialiseXHRStreamingTransport from './xhrstreamingtransport';
 
-export default [initialiseXHRPollingTransport, initialiseXHRStreamingTransport];
+export default {
+  order: [TransportName.XhrPolling, TransportName.XhrStreaming],
+  implementations: {
+    [TransportName.XhrPolling]: initialiseXHRPollingTransport,
+    [TransportName.XhrStreaming]: initialiseXHRStreamingTransport,
+  },
+};