feat: Add separate handlers for API Gateway (REST APIs), API Gateway V2 (HTTP APIs), and Lambda function URLs to Typescript impl

Author: clareliguori

src/typescript/src/handlers/api_gateway_proxy_event_handler.ts

@@ -0,0 +1,55 @@
+import { APIGatewayProxyEvent, APIGatewayProxyResult } from "aws-lambda";
+import {
+  StreamableHttpHandler,
+  ParsedHttpRequest,
+  HttpResponse,
+} from "./streamable_http_handler.js";
+import { RequestHandler } from "./request_handler.js";
+
+/**
+ * Handler for API Gateway V1 events (REST APIs)
+ *
+ * This handler processes APIGatewayProxyEvent events (Lambda proxy integration behind API Gateway REST API)
+ * and returns APIGatewayProxyResult responses.
+ *
+ * This class handles all the generic JSON-RPC protocol aspects of the MCP Streamable HTTP transport:
+ * - HTTP method validation (POST, OPTIONS, GET)
+ * - Content-Type and Accept header validation
+ * - JSON parsing and validation
+ * - Batch request handling
+ * - CORS headers
+ * - Error response formatting
+ * This class does not implement session management.
+ *
+ * The specific business logic is delegated to a provided RequestHandler implementation.
+ */
+export class APIGatewayProxyEventHandler extends StreamableHttpHandler<
+  APIGatewayProxyEvent,
+  APIGatewayProxyResult
+> {
+  constructor(requestHandler: RequestHandler) {
+    super(requestHandler);
+  }
+
+  /**
+   * Parse APIGatewayProxyEvent into common HTTP request format
+   */
+  protected parseEvent(event: APIGatewayProxyEvent): ParsedHttpRequest {
+    return {
+      method: event.httpMethod,
+      headers: event.headers || {},
+      body: event.body || null,
+    };
+  }
+
+  /**
+   * Format HTTP response as APIGatewayProxyResult
+   */
+  protected formatResponse(response: HttpResponse): APIGatewayProxyResult {
+    return {
+      statusCode: response.statusCode,
+      headers: response.headers,
+      body: response.body,
+    };
+  }
+}

src/typescript/src/handlers/api_gateway_proxy_event_v2_handler.ts

@@ -0,0 +1,54 @@
+import { APIGatewayProxyEventV2, APIGatewayProxyResultV2 } from "aws-lambda";
+import {
+  StreamableHttpHandler,
+  ParsedHttpRequest,
+  HttpResponse,
+} from "./streamable_http_handler.js";
+import { RequestHandler } from "./request_handler.js";
+
+/**
+ * Handler for API Gateway V2 events (HTTP APIs)
+ *
+ * This handler processes APIGatewayProxyEventV2 events and returns APIGatewayProxyResultV2 responses.
+ *
+ * This class handles all the generic JSON-RPC protocol aspects of the MCP Streamable HTTP transport:
+ * - HTTP method validation (POST, OPTIONS, GET)
+ * - Content-Type and Accept header validation
+ * - JSON parsing and validation
+ * - Batch request handling
+ * - CORS headers
+ * - Error response formatting
+ * This class does not implement session management.
+ *
+ * The specific business logic is delegated to a provided RequestHandler implementation.
+ */
+export class APIGatewayProxyEventV2Handler extends StreamableHttpHandler<
+  APIGatewayProxyEventV2,
+  APIGatewayProxyResultV2
+> {
+  constructor(requestHandler: RequestHandler) {
+    super(requestHandler);
+  }
+
+  /**
+   * Parse APIGatewayProxyEventV2 into common HTTP request format
+   */
+  protected parseEvent(event: APIGatewayProxyEventV2): ParsedHttpRequest {
+    return {
+      method: event.requestContext.http.method,
+      headers: event.headers || {},
+      body: event.body || null,
+    };
+  }
+
+  /**
+   * Format HTTP response as APIGatewayProxyResultV2
+   */
+  protected formatResponse(response: HttpResponse): APIGatewayProxyResultV2 {
+    return {
+      statusCode: response.statusCode,
+      headers: response.headers,
+      body: response.body,
+    };
+  }
+}