server/utils/renderMjml: add types & named export

Author: clairep94

server/utils/renderMjml.ts

@@ -1,13 +1,14 @@
+/* eslint-disable consistent-return */
 import mjml2html from 'mjml';
 
-export default (template) => {
+/** Parse template string containing mjml tags into html for nodemailer.SendMailOptions.html */
+export function renderMjml(template: string): string | undefined {
   try {
     const output = mjml2html(template);
     return output.html;
   } catch (e) {
     console.error(e);
-    // fall through to null
+    // fall through to undefined (null is not valid for nodemailer.SendMailOptions.html)
+    return undefined;
   }
-
-  return null;
-};
+}

server/views/mail.js

@@ -1,4 +1,4 @@
-import renderMjml from '../utils/renderMjml';
+import { renderMjml } from '../utils/renderMjml';
 import { mailLayout } from './mailLayout';
 import { consolidationMailLayout } from './consolidationMailLayout';