fix(firestore-send-email): SendGrid v3 issues (#2020)

* fix(firestore-send-email): sendgrid v3 issues

* fix(firestore-send-email): remove sendgrid transporter test

* fix(firestore-send-email): handle sendgrid template edge cases

* chore: clean up comments & logs

---------

Co-authored-by: Pavel <k>

Author: jauntybrain

firestore-send-email/functions/__tests__/helpers.test.ts

@@ -216,6 +216,7 @@ describe("set server credentials helper function", () => {
     expect(regex.test(config.smtpConnectionUri)).toBe(false);
   });
 
+  /* Test removed due to the new SendGrid transporter logic - see setSendGridTransport()
   test("return a SendGrid transporter if the host is smtp.sendgrid.net", () => {
     const config: Config = {
       smtpConnectionUri: "smtps://apikey@smtp.sendgrid.net:465",
@@ -227,4 +228,5 @@ describe("set server credentials helper function", () => {
     const credentials = setSmtpCredentials(config);
     expect(credentials.transporter.name === "nodemailer-sendgrid").toBe(true);
   });
+  */
 });

firestore-send-email/functions/src/helpers.ts

@@ -70,12 +70,6 @@ export function setSmtpCredentials(config: Config) {
         pass: decodeURIComponent(url.password),
       },
     });
-  } else if (checkSendGrid(url.hostname)) {
-    const options: sg.SendgridOptions = {
-      apiKey: decodeURIComponent(url.password),
-    };
-
-    transport = createTransport(sg(options));
   } else {
     transport = createTransport(url.href, {
       tls: parseTlsOptions(config.tls),
@@ -84,3 +78,13 @@ export function setSmtpCredentials(config: Config) {
 
   return transport;
 }
+
+export function setSendGridTransport(config: Config) {
+  const { smtpPassword } = config;
+
+  const options: sg.SendgridOptions = {
+    apiKey: smtpPassword,
+  };
+
+  return createTransport(sg(options));
+}

firestore-send-email/functions/src/index.ts

@@ -23,7 +23,11 @@ import * as logs from "./logs";
 import config from "./config";
 import Templates from "./templates";
 import { QueuePayload } from "./types";
-import { parseTlsOptions, setSmtpCredentials } from "./helpers";
+import {
+  parseTlsOptions,
+  setSendGridTransport,
+  setSmtpCredentials,
+} from "./helpers";
 import * as events from "./events";
 
 logs.init();
@@ -292,16 +296,31 @@ async function deliver(
   try {
     payload = await preparePayload(payload);
 
-    // If the SMTP provider is SendGrid, we need to check if the payload contains
-    // either a text or html content, or if the payload contains a SendGrid Dynamic Template.
-    verifySendGridContent(payload);
-
     if (!payload.to.length && !payload.cc.length && !payload.bcc.length) {
       throw new Error(
         "Failed to deliver email. Expected at least 1 recipient."
       );
     }
 
+    // Switch to SendGrid transport if SendGrid config is provided.
+    if (payload.sendGrid) {
+      transport = setSendGridTransport(config);
+
+      // Convert text and html to undefined if they are null
+      if (payload.message) {
+        if (payload.message.text == null) {
+          payload.message.text = undefined;
+        }
+        if (payload.message.html == null) {
+          payload.message.text = undefined;
+        }
+      }
+
+      // If the SMTP provider is SendGrid, we need to check if the payload contains
+      // either a text or html content, or if the payload contains a SendGrid Dynamic Template.
+      verifySendGridContent(payload);
+    }
+
     const result = await transport.sendMail({
       ...Object.assign(payload.message ?? {}, {
         from: payload.from || config.defaultFrom,
@@ -315,6 +334,7 @@ async function deliver(
         mail_settings: payload.sendGrid?.mailSettings || {},
       }),
     });
+
     const info = {
       messageId: result.messageId || null,
       accepted: result.accepted || [],
@@ -325,6 +345,7 @@ async function deliver(
 
     update["delivery.state"] = "SUCCESS";
     update["delivery.info"] = info;
+
     logs.delivered(ref, info);
   } catch (e) {
     update["delivery.state"] = "ERROR";