feat: add trpc route to send emails

packages/lib/server-only/document/send-document.ts

@@ -0,0 +1,39 @@
+import nodemailer from 'nodemailer';
+import nodemailerSendgrid from 'nodemailer-sendgrid';
+
+export const sendMail = async ({ email }: { email: string }) => {
+  let transporter;
+
+  if (process.env.NEXT_PRIVATE_SENDGRID_API_KEY) {
+    transporter = nodemailer.createTransport(
+      nodemailerSendgrid({
+        apiKey: process.env.NEXT_PRIVATE_SENDGRID_API_KEY,
+      }),
+    );
+  }
+
+  if (process.env.NEXT_PRIVATE_SMTP_MAIL_HOST) {
+    transporter = nodemailer.createTransport({
+      host: process.env.NEXT_PRIVATE_SMTP_MAIL_HOST,
+      port: Number(process.env.NEXT_PRIVATE_SMTP_MAIL_PORT),
+      auth: {
+        user: process.env.NEXT_PRIVATE_SMTP_MAIL_USER,
+        pass: process.env.NEXT_PRIVATE_SMTP_MAIL_PASSWORD,
+      },
+    });
+  }
+
+  if (!transporter) {
+    throw new Error(
+      'No mail transport configured. Probably Sendgrid API Key nor SMTP Mail host was set',
+    );
+  }
+
+  await transporter.sendMail({
+    from: 'Documenso <hi@documenso.com>',
+    to: email,
+    subject: 'Welcome to Documenso!',
+    text: 'Welcome to Documenso!',
+    html: '<p>Welcome to Documenso!</p>',
+  });
+};