From 636af2a5db590db685ba4d601539f8200e6c0daf Mon Sep 17 00:00:00 2001
From: Joaquin Ormaechea <joaquinormaechea@gmail.com>
Date: Tue, 10 Sep 2019 21:44:17 -0300
Subject: [PATCH] Avoid setting empty response headers

Fixes #804 for v5.x.x
---
 src/ApiGateway.js | 17 ++++++++++-------
 1 file changed, 10 insertions(+), 7 deletions(-)

diff --git a/src/ApiGateway.js b/src/ApiGateway.js
index bbfdb7798..a567ec21e 100644
--- a/src/ApiGateway.js
+++ b/src/ApiGateway.js
@@ -664,9 +664,6 @@ module.exports = class ApiGateway {
                             : result
                           );
                           if(typeof headerValue === 'undefined' || headerValue === null) {
-	                          debugLog(
-	                            `Warning: empty value for responseParameter "${key}": "${value}"`,
-	                          );
                             headerValue = '';
                           } else {
                             headerValue = headerValue.toString();
@@ -688,10 +685,16 @@ module.exports = class ApiGateway {
                           : value; // See #34
                       }
                       // Applies the header;
-                      debugLog(
-                        `Will assign "${headerValue}" to header "${headerName}"`,
-                      );
-                      response.header(headerName, headerValue);
+                      if (headerValue === '') {
+                        this.serverlessLog(
+                          `Warning: empty value for responseParameter "${key}": "${value}", it won't be set`,
+                        );
+                      } else {
+                        debugLog(
+                          `Will assign "${headerValue}" to header "${headerName}"`,
+                        );
+                        response.header(headerName, headerValue);
+                      }
                     } else {
                       this.printBlankLine();
                       this.serverlessLog(