WIP - Mixed content error for Issue #543 (#661)

* Set trust proxy option on Express app.

* Fix replacement of filePath for full screen and embed sketches.

* Use const rather than let because  is never reassigned.

Author: jareddonovan

server/server.js

@@ -45,6 +45,8 @@ if (process.env.NODE_ENV === 'development') {
   corsOriginsWhitelist.push(/localhost/);
 }
 
+app.set('trust proxy', true);
+
 // Enable Cross-Origin Resource Sharing (CORS) for all origins
 const corsMiddleware = cors({
   credentials: true,

server/utils/previewGeneration.js

@@ -29,7 +29,8 @@ function resolveLinksInString(content, files, projectId) {
           while (resolvedFilePath.startsWith('/')) {
             resolvedFilePath = resolvedFilePath.substr(1);
           }
-          newContent = newContent.replace(filePath, `/sketches/${projectId}/assets/${resolvedFilePath}`);
+          const replacement = `/sketches/${projectId}/assets/${resolvedFilePath}`;
+          newContent = newContent.replace(filePath, replacement);
         }
       }
     }