add usePathPrefixInHandlers option to EventSubMiddleware and ReverseP…

…roxyAdapter

defaults to true in the former, false in the latter (to not break BC)

packages/eventsub/src/EventSubListener.ts

@@ -81,9 +81,28 @@ export class EventSubListener extends EventSubBase {
 			});
 			next();
 		});
-		this._server.get('/', this._createHandleHealthRequest());
-		this._server.post('/:id', this._createDropLegacyRequest());
-		this._server.post('/event/:id', this._createHandleRequest());
+		let requestPathPrefix: string | undefined = undefined;
+		if (this._adapter.usePathPrefixInHandlers) {
+			requestPathPrefix = this._adapter.pathPrefix;
+			if (requestPathPrefix) {
+				requestPathPrefix = `/${requestPathPrefix.replace(/^\/|\/$/g, '')}`;
+			}
+		}
+
+		const healthHandler = this._createHandleHealthRequest();
+		const dropLegacyHandler = this._createDropLegacyRequest();
+		const requestHandler = this._createHandleRequest();
+
+		if (requestPathPrefix) {
+			this._server.post(`${requestPathPrefix}/event/:id`, requestHandler);
+			this._server.post(`${requestPathPrefix}/:id`, dropLegacyHandler);
+			this._server.get(`${requestPathPrefix}`, healthHandler);
+		} else {
+			this._server.post('/event/:id', requestHandler);
+			this._server.post('/:id', dropLegacyHandler);
+			this._server.get('/', healthHandler);
+		}
+
 		const adapterListenerPort = await this._adapter.getListenerPort();
 		if (adapterListenerPort && port) {
 			this._logger.warn(`Your passed port (${port}) is being ignored because the adapter has overridden it.

packages/eventsub/src/EventSubMiddleware.ts

@@ -1,5 +1,5 @@
 import { rtfm } from '@twurple/common';
-import type { Express, RequestHandler } from 'express-serve-static-core';
+import type { IRouter, RequestHandler } from 'express-serve-static-core';
 import { checkHostName } from './checks';
 import type { EventSubBaseConfig } from './EventSubBase';
 import { EventSubBase } from './EventSubBase';
@@ -19,6 +19,13 @@ export interface EventSubMiddlewareConfig extends EventSubBaseConfig {
 	 * The path your listener is mounted under.
 	 */
 	pathPrefix?: string;
+
+	/**
+	 * Whether the path prefix will added to the mount point. Defaults to `true`.
+	 *
+	 * Must be `false` if you use this with subrouters.
+	 */
+	usePathPrefixInHandlers?: boolean;
 }
 
 /**
@@ -33,6 +40,7 @@ export interface EventSubMiddlewareConfig extends EventSubBaseConfig {
 export class EventSubMiddleware extends EventSubBase {
 	private readonly _hostName: string;
 	private readonly _pathPrefix?: string;
+	private readonly _usePathPrefixInHandlers: boolean;
 
 	/**
 	 * Creates a new EventSub middleware wrapper.
@@ -48,29 +56,33 @@ export class EventSubMiddleware extends EventSubBase {
 
 		this._hostName = config.hostName;
 		this._pathPrefix = config.pathPrefix;
+		this._usePathPrefixInHandlers = config.usePathPrefixInHandlers ?? true;
 	}
 
 	/**
-	 * Applies middleware that handles EventSub notifications to an Express app.
+	 * Applies middleware that handles EventSub notifications to an Express app/router.
 	 *
-	 * @param app The app the middleware should be applied to.
+	 * @param router The app or router the middleware should be applied to.
 	 */
-	async apply(app: Express): Promise<void> {
-		let pathPrefix = this._pathPrefix;
-		if (pathPrefix) {
-			pathPrefix = `/${pathPrefix.replace(/^\/|\/$/g, '')}`;
+	async apply(router: IRouter): Promise<void> {
+		let requestPathPrefix: string | undefined = undefined;
+		if (this._usePathPrefixInHandlers) {
+			requestPathPrefix = this._pathPrefix;
+			if (requestPathPrefix) {
+				requestPathPrefix = `/${requestPathPrefix.replace(/^\/|\/$/g, '')}`;
+			}
 		}
 		const requestHandler = this._createHandleRequest() as unknown as RequestHandler;
 		const dropLegacyHandler = this._createDropLegacyRequest() as unknown as RequestHandler;
 		const healthHandler = this._createHandleHealthRequest() as unknown as RequestHandler;
-		if (pathPrefix) {
-			app.post(`${pathPrefix}/event/:id`, requestHandler);
-			app.post(`${pathPrefix}/:id`, dropLegacyHandler);
-			app.get(`${pathPrefix}`, healthHandler);
+		if (requestPathPrefix) {
+			router.post(`${requestPathPrefix}/event/:id`, requestHandler);
+			router.post(`${requestPathPrefix}/:id`, dropLegacyHandler);
+			router.get(`${requestPathPrefix}`, healthHandler);
 		} else {
-			app.post('event/:id', requestHandler);
-			app.post(':id', dropLegacyHandler);
-			app.get('/', healthHandler);
+			router.post('event/:id', requestHandler);
+			router.post(':id', dropLegacyHandler);
+			router.get('/', healthHandler);
 		}
 	}
 

packages/eventsub/src/adapters/ConnectionAdapter.ts

@@ -44,13 +44,25 @@ export abstract class ConnectionAdapter {
 	/**
 	 * The path prefix an external connection needs to reach this server.
 	 *
-	 * Please note that the layer redirecting to this server needs to strip the path prefix in order for this to work.
-	 *
-	 * For example, if this is set to /hooks, an external connection to /hooks/abc should pass /abc as the path to this server.
-	 *
 	 * @protected
 	 */
 	get pathPrefix(): string | undefined {
 		return undefined;
 	}
+
+	/**
+	 * Whether the path prefix is passed to the handler.
+	 *
+	 * Defaults to `false` which means that the layer redirecting to this server needs to strip the path prefix in order for it to work.
+	 *
+	 * For example, if the path prefix is set to /hooks, an external connection to /hooks/abc should pass /abc as the path to this server.
+	 *
+	 * Conversely, if this is set to `true`, the path should be passed as is (i.e. /hooks/abc).
+	 *
+	 * @protected
+	 */
+	// eslint-disable-next-line @typescript-eslint/class-literal-property-style
+	get usePathPrefixInHandlers(): boolean {
+		return false;
+	}
 }

packages/eventsub/src/adapters/ReverseProxyAdapter.ts

@@ -22,6 +22,17 @@ export interface ReverseProxyAdapterConfig {
 	 * The path prefix your reverse proxy redirects to the listener.
 	 */
 	pathPrefix?: string;
+
+	/**
+	 * Whether the path prefix is passed to the handler.
+	 *
+	 * Defaults to `false` which means that the layer redirecting to this server needs to strip the path prefix in order for it to work.
+	 *
+	 * For example, if the path prefix is set to /hooks, an external connection to /hooks/abc should pass /abc as the path to this server.
+	 *
+	 * Conversely, if this is set to `true`, the path should be passed as is (i.e. /hooks/abc).
+	 */
+	usePathPrefixInHandlers?: boolean;
 }
 
 /**
@@ -34,6 +45,7 @@ export class ReverseProxyAdapter extends ConnectionAdapter {
 	private readonly _hostName: string;
 	private readonly _port: number;
 	private readonly _pathPrefix?: string;
+	private readonly _usePathPrefixInHandlers: boolean;
 
 	/**
 	 * Creates a reverse proxy connection adapter.
@@ -50,6 +62,7 @@ export class ReverseProxyAdapter extends ConnectionAdapter {
 		this._hostName = options.hostName;
 		this._port = options.port ?? 8080;
 		this._pathPrefix = options.pathPrefix;
+		this._usePathPrefixInHandlers = options.usePathPrefixInHandlers ?? false;
 	}
 
 	/** @protected */
@@ -66,4 +79,9 @@ export class ReverseProxyAdapter extends ConnectionAdapter {
 	get pathPrefix(): string | undefined {
 		return this._pathPrefix;
 	}
+
+	/** @protected */
+	get usePathPrefixInHandlers(): boolean {
+		return this._usePathPrefixInHandlers;
+	}
 }