From c66c789d802cbb4ad3cb865dafa2b1f79291b5ab Mon Sep 17 00:00:00 2001
From: "N. Ben Cohen" <breathevalue@icloud.com>
Date: Wed, 23 Aug 2017 00:05:34 -0400
Subject: [PATCH] Augment LambdaServer to use URL path parameter from request
 to lookup module information when path information is supplied in url

---
 lib/client/lambda-server.ts       | 24 ++++++++++++++----
 test/client/lambda-server-test.ts | 42 ++++++++++++++++++++++++++++++-
 2 files changed, 60 insertions(+), 6 deletions(-)

diff --git a/lib/client/lambda-server.ts b/lib/client/lambda-server.ts
index f0174c4e..ec20b937 100644
--- a/lib/client/lambda-server.ts
+++ b/lib/client/lambda-server.ts
@@ -19,7 +19,6 @@ export class LambdaServer {
     private requests: Array<IncomingMessage> = [];
     private server: Server = null;
 
-
     /**
      * Creates a server that exposes a Lambda as an HTTP service
      * @param file The file the defines the Lambda
@@ -27,7 +26,7 @@ export class LambdaServer {
      * @param verbose Prints out verbose information about requests and responses
      * @param functionName Use the named function as opposed to the default ("handler")
      */
-    public constructor(private file: string, private port: number, private verbose?: boolean, private functionName?: string) {}
+    public constructor(private file?: string, private port?: number, private verbose?: boolean, private functionName?: string) {}
 
     /**
      * Starts the LambdaServer listening on the port specified in the constructor.
@@ -92,12 +91,27 @@ export class LambdaServer {
     }
 
     private invoke (request: IncomingMessage, body: Buffer, response: ServerResponse): void {
-        let path: string = this.file;
+        let path: string;
+        let handlerFunction: string;
+        const context: LambdaContext = new LambdaContext(request, body, response, this.verbose);
+
+        if (request.url !== "/") {
+            // verify that path does not contain '..' or node_modules anywhere
+            if (/(.*\.\.)|(.*node_modules)/.test(request.url)) {
+                context.fail(Error(`LambdaServer input url should not contain '..' or node_modules characters found: ${request.url}`));
+                return;
+            }
+            [path, handlerFunction] = request.url.split(":");
+        }
+        else {
+            // no url argument supplied -- use file parameter (supplied in constructor) instead
+            path = this.file;
+        }
+
         LoggingHelper.debug(Logger, "Invoking Lambda: " + path);
 
         const lambda = this.moduleManager.module(path);
         // let lambda = System.import("./" + file);
-        const context: LambdaContext = new LambdaContext(request, body, response, this.verbose);
         try {
             const bodyToString = body.toString();
             const bodyJSON: any = JSON.parse(bodyToString === "" ? null : bodyToString);
@@ -107,7 +121,7 @@ export class LambdaServer {
                 console.log(JSON.stringify(bodyJSON, null, 2));
             }
 
-            const handlerFunction = this.functionName ? this.functionName : "handler";
+            handlerFunction = handlerFunction != null ? handlerFunction : this.functionName ? this.functionName : "handler";
             lambda[handlerFunction](bodyJSON, context, function(error: Error, result: any) {
                 context.done(error, result);
             });
diff --git a/test/client/lambda-server-test.ts b/test/client/lambda-server-test.ts
index c15d726e..6b0b4099 100644
--- a/test/client/lambda-server-test.ts
+++ b/test/client/lambda-server-test.ts
@@ -122,7 +122,7 @@ describe("LambdaServer", function() {
         });
 
         it("Uses Callback With Failure", function(done) {
-            let runner = new LambdaServer("CallbackLambda.js", 10000);
+            let runner = new LambdaServer("CallbackLambda", 10000);
             runner.start();
 
             let client = new HTTPClient();
@@ -134,6 +134,46 @@ describe("LambdaServer", function() {
             });
         });
 
+        it("Invoke uses URL to find module when URL is present", function(done) {
+            let runner = new LambdaServer(null, 10000);
+            runner.start();
+
+            let client = new HTTPClient();
+            let inputData = {"data": "Test"};
+            client.post("localhost", 10000, "/exampleProject/ExampleLambda.js:handler", JSON.stringify(inputData), function(data: Buffer) {
+                let o: any = JSON.parse(data.toString());
+                assert(true, o.success);
+                runner.stop();
+                done();
+            });
+        });
+
+        it("Invoke with URL of valid module and invalid handler should raise error", function(done) {
+            let runner = new LambdaServer(null, 10000);
+            runner.start();
+
+            let client = new HTTPClient();
+            let inputData = {"data": "Test"};
+            client.post("localhost", 10000, "/exampleProject/ExampleLambda.js:fakehandler", JSON.stringify(inputData), function(data: Buffer) {
+                assert.equal(data.toString(), "Unhandled Exception from Lambda: TypeError: lambda[handlerFunction] is not a function");
+                runner.stop();
+                done();
+            });
+        });
+
+        it("Invoke with illegal url passed to find LambdaServer.invoke should raise error", function(done) {
+            let runner = new LambdaServer(null, 10000);
+            runner.start();
+
+            let client = new HTTPClient();
+            let inputData = {"data": "Test"};
+            client.post("localhost", 10000, "/node_modules/exampleProject/ExampleLambda.js:fakeHandler", JSON.stringify(inputData), function(data: Buffer) {
+                assert.equal(data.toString(), "Unhandled Exception from Lambda: Error: LambdaServer input url should not contain '..' or node_modules characters found: /node_modules/exampleProject/ExampleLambda.js:fakeHandler");
+                runner.stop();
+                done();
+            });
+        });
+
         it("Checks Context Stuff", function(done) {
             let runner = new LambdaServer("ContextLambda.js", 10000);
             runner.start();