Trigger Email from Firestore

Use this extension to render and send emails that contain the information from documents added to a specified Cloud Firestore collection.

Adding a document triggers this extension to send an email built from the document’s fields. The document’s top-level fields specify the email sender and recipients, including to, cc, and bcc options (each supporting UIDs). The document’s message field specifies the other email elements, like subject line and email body (either plaintext or HTML)

Here’s a basic example document write that would trigger this extension:

admin.firestore().collection('mail').add({
  to: 'someone@example.com',
  message: {
    subject: 'Hello from Firebase!',
    html: 'This is an <code>HTML</code> email body.',
  },
})

You can also optionally configure this extension to render emails using Handlebar templates. Each template is a document stored in a Cloud Firestore collection.

When you configure this extension, you’ll need to supply your SMTP credentials for mail delivery. Note that this extension is for use with bulk email service providers, like SendGrid, Mailgun, etc.

Firestore-Send-Email: SendGrid Categories

When using SendGrid (SMTP_CONNECTION_URI includes sendgrid.net), you can assign categories to your emails.

Example JSON with Categories:

{
  "to": ["example@example.com"],
  "categories": ["Example_Category"],
  "message": {
    "subject": "Test Email with Categories",
    "text": "This is a test email to see if categories work.",
    "html": "<strong>This is a test email to see if categories work.</strong>"
  }
}

Add this document to the Firestore mail collection to send categorized emails.

For more details, see the SendGrid Categories documentation.

Setup Google App Passwords

Google no longer allows Gmail users to use their own passwords to authorize third-party apps and services. Instead, you have to use the Sign in with App Passwords service to generate a special password for each app you want to authorize. To do so:

1. Go to your Google Account.
2. Select Security.
3. Under “Signing in to Google,” select App Passwords. You may need to sign in. If you don’t have this option, it might be because:
   1. 2-Step Verification is not set up for your account.
   2. 2-Step Verification is only set up for security keys.
   3. Your account is through work, school, or other organization.
   4. You turned on Advanced Protection.
4. At the bottom, choose Select app and choose Other option and then write the name of the app password (e.g. Firebase Trigger Email from Firestore Extension) and click Generate.
5. Follow the instructions to enter the App Password. The App Password is the 16-character code in the yellow bar on your device.
6. Tap Done.

Now you can use your Google username with the generated password to authorize the extension.

Setup Hotmail Passwords

To use your Outlook/Hotmail email account with this extension, you’ll need to have 2FA enabled on your account, and Create an App Password.

Additional setup

Before installing this extension, make sure that you’ve set up a Cloud Firestore database in your Firebase project.

Automatic Deletion of Email Documents

To use Firestore’s TTL feature for automatic deletion of expired email documents, the extension provides several configuration parameters.

The extension will set a TTL field in the email documents, but you will need to manually configure a TTL policy for the collection/collection group the extension targets, on the delivery.expireAt field.

Detailed instructions for creating a TTL field can be found in the Firestore TTL Policy documentation.

Billing

To install an extension, your project must be on the Blaze (pay as you go) plan

• This extension uses other Firebase and Google Cloud Platform services, which have associated charges if you exceed the service’s no-cost tier:
  • Cloud Firestore
  • Cloud Functions (Node.js 10+ runtime. See FAQs)

Usage of this extension also requires you to have SMTP credentials for mail delivery. You are responsible for any associated costs with your usage of your SMTP provider.

Further reading & resources

You can find more information about this extension in the following articles:

• Sending Emails Using Firestore And Firebase Extensions