Compat Layer status code fixes

packages/apigw-lambda-compat/lib/__tests__/compatLayer.response.test.js

@@ -56,6 +56,23 @@ describe("compatLayer.response", () => {
     res.end();
   });
 
+  it("[Promise] statusCode statusCode=200 by default", () => {
+    expect.assertions(1);
+
+    const { res, responsePromise } = create({
+      requestContext: {
+        path: "/"
+      },
+      headers: {}
+    });
+
+    res.end();
+
+    return responsePromise.then(response => {
+      expect(response.statusCode).toEqual(200);
+    });
+  });
+
   it("[Promise] statusCode statusCode=200", () => {
     expect.assertions(1);
 
@@ -452,4 +469,21 @@ describe("compatLayer.response", () => {
       expect(response.isBase64Encoded).toEqual(true);
     });
   });
+
+  it("response does not have a body if only statusCode is set", () => {
+    const { res, responsePromise } = create({
+      requestContext: {
+        path: "/"
+      },
+      headers: {}
+    });
+
+    res.statusCode = 204;
+    res.end();
+
+    return responsePromise.then(response => {
+      expect(response.body).not.toBeDefined();
+      expect(response.statusCode).toEqual(204);
+    });
+  });
 });

packages/apigw-lambda-compat/lib/compatLayer.js

@@ -5,9 +5,7 @@ const http = require("http");
 const reqResMapper = (event, callback) => {
   const base64Support = process.env.BINARY_SUPPORT === "yes";
   const response = {
-    body: Buffer.from(""),
     isBase64Encoded: base64Support,
-    statusCode: 200,
     multiValueHeaders: {}
   };
   let responsePromise;
@@ -80,6 +78,10 @@ const reqResMapper = (event, callback) => {
     if (headers) res.headers = Object.assign(res.headers, headers);
   };
   res.write = chunk => {
+    if (!response.body) {
+      response.body = Buffer.from("");
+    }
+
     response.body = Buffer.concat([
       Buffer.isBuffer(response.body)
         ? response.body
@@ -105,9 +107,15 @@ const reqResMapper = (event, callback) => {
 
   const onResEnd = (callback, resolve) => text => {
     if (text) res.write(text);
-    response.body = Buffer.from(response.body).toString(
-      base64Support ? "base64" : undefined
-    );
+    if (!res.statusCode) {
+      res.statusCode = 200;
+    }
+
+    if (response.body) {
+      response.body = Buffer.from(response.body).toString(
+        base64Support ? "base64" : undefined
+      );
+    }
     response.multiValueHeaders = res.headers;
     res.writeHead(response.statusCode);
     fixApiGatewayMultipleHeaders();

packages/lambda-at-edge-compat/__tests__/next-aws-cloudfront.response.test.js

@@ -21,7 +21,7 @@ describe("Response Tests", () => {
   });
 
   it("statusCode statusCode=200", () => {
-    expect.assertions(1);
+    expect.assertions(2);
 
     const { res, responsePromise } = create({
       request: {
@@ -33,6 +33,24 @@ describe("Response Tests", () => {
     res.statusCode = 200;
     res.end();
 
+    return responsePromise.then(response => {
+      expect(response.status).toEqual(200);
+      expect(response.statusDescription).toEqual("OK");
+    });
+  });
+
+  it("statusCode statusCode=200 by default", () => {
+    expect.assertions(1);
+
+    const { res, responsePromise } = create({
+      request: {
+        uri: "/",
+        headers: {}
+      }
+    });
+
+    res.end();
+
     return responsePromise.then(response => {
       expect(response.status).toEqual(200);
     });
@@ -265,6 +283,8 @@ describe("Response Tests", () => {
   });
 
   it(`res.write('ok')`, () => {
+    expect.assertions(2);
+
     const { res, responsePromise } = create({
       request: {
         path: "/",
@@ -277,10 +297,13 @@ describe("Response Tests", () => {
 
     return responsePromise.then(response => {
       expect(response.body).toEqual("b2s=");
+      expect(response.bodyEncoding).toEqual("base64");
     });
   });
 
   it(`res.end('ok')`, () => {
+    expect.assertions(1);
+
     const { res, responsePromise } = create({
       request: {
         path: "/",
@@ -296,6 +319,8 @@ describe("Response Tests", () => {
   });
 
   it(`gzips`, () => {
+    expect.assertions(2);
+
     const gzipSpy = jest.spyOn(zlib, "gzipSync");
     gzipSpy.mockReturnValueOnce(Buffer.from("ok-gzipped"));
 
@@ -324,4 +349,25 @@ describe("Response Tests", () => {
       expect(response.body).toEqual("b2stZ3ppcHBlZA=="); // "ok-gzipped" base64 encoded
     });
   });
+
+  it("response does not have a body if only statusCode is set", () => {
+    expect.assertions(4);
+
+    const { res, responsePromise } = create({
+      request: {
+        path: "/",
+        headers: {}
+      }
+    });
+
+    res.statusCode = 204;
+    res.end();
+
+    return responsePromise.then(response => {
+      expect(response.body).not.toBeDefined();
+      expect(response.bodyEncoding).not.toBeDefined();
+      expect(response.status).toEqual(204);
+      expect(response.statusDescription).toEqual("No Content");
+    });
+  });
 });

packages/lambda-at-edge-compat/next-aws-cloudfront.js

@@ -33,6 +33,63 @@ const readOnlyCloudFrontHeaders = {
   via: true
 };
 
+const HttpStatusCodes = {
+  202: "Accepted",
+  502: "Bad Gateway",
+  400: "Bad Request",
+  409: "Conflict",
+  100: "Continue",
+  201: "Created",
+  417: "Expectation Failed",
+  424: "Failed Dependency",
+  403: "Forbidden",
+  504: "Gateway Timeout",
+  410: "Gone",
+  505: "HTTP Version Not Supported",
+  418: "I'm a teapot",
+  419: "Insufficient Space on Resource",
+  507: "Insufficient Storage",
+  500: "Server Error",
+  411: "Length Required",
+  423: "Locked",
+  420: "Method Failure",
+  405: "Method Not Allowed",
+  301: "Moved Permanently",
+  302: "Moved Temporarily",
+  207: "Multi-Status",
+  300: "Multiple Choices",
+  511: "Network Authentication Required",
+  204: "No Content",
+  203: "Non Authoritative Information",
+  406: "Not Acceptable",
+  404: "Not Found",
+  501: "Not Implemented",
+  304: "Not Modified",
+  200: "OK",
+  206: "Partial Content",
+  402: "Payment Required",
+  308: "Permanent Redirect",
+  412: "Precondition Failed",
+  428: "Precondition Required",
+  102: "Processing",
+  407: "Proxy Authentication Required",
+  431: "Request Header Fields Too Large",
+  408: "Request Timeout",
+  413: "Request Entity Too Large",
+  414: "Request-URI Too Long",
+  416: "Requested Range Not Satisfiable",
+  205: "Reset Content",
+  303: "See Other",
+  503: "Service Unavailable",
+  101: "Switching Protocols",
+  307: "Temporary Redirect",
+  429: "Too Many Requests",
+  401: "Unauthorized",
+  422: "Unprocessable Entity",
+  415: "Unsupported Media Type",
+  305: "Use Proxy"
+};
+
 const toCloudFrontHeaders = headers => {
   const result = {};
 
@@ -83,10 +140,6 @@ const handler = event => {
   const { request: cfRequest } = event;
 
   const response = {
-    body: Buffer.from(""),
-    bodyEncoding: "base64",
-    status: 200,
-    statusDescription: "OK",
     headers: {}
   };
 
@@ -141,31 +194,48 @@ const handler = event => {
     },
     set(statusCode) {
       response.status = statusCode;
+      response.statusDescription = HttpStatusCodes[statusCode];
     }
   });
 
   res.headers = {};
   res.writeHead = (status, headers) => {
     response.status = status;
+
     if (headers) {
       res.headers = Object.assign(res.headers, headers);
     }
   };
   res.write = chunk => {
+    if (!response.body) {
+      response.body = Buffer.from("");
+    }
+
     response.body = Buffer.concat([
       response.body,
       Buffer.isBuffer(chunk) ? chunk : Buffer.from(chunk)
     ]);
   };
+
   let gz = isGzipSupported(headers);
 
   const responsePromise = new Promise(resolve => {
     res.end = text => {
       if (text) res.write(text);
+
+      if (!res.statusCode) {
+        res.statusCode = 200;
+      }
+
       res.finished = true;
-      response.body = gz
-        ? zlib.gzipSync(response.body).toString("base64")
-        : Buffer.from(response.body).toString("base64");
+
+      if (response.body) {
+        response.bodyEncoding = "base64";
+        response.body = gz
+          ? zlib.gzipSync(response.body).toString("base64")
+          : Buffer.from(response.body).toString("base64");
+      }
+
       response.headers = toCloudFrontHeaders(res.headers);
 
       if (gz) {