Use Handlebars templates with the Trigger Email extension
Stay organized with collections
Save and categorize content based on your preferences.
If you specified a "Templates collection" parameter during configuration of the
extension, you can create and manage Handlebars templates
templates for your emails.
Template collection structure
Give each document a memorable ID that you use as the template name in the
documents you write to your templates collection.
The template document can include any of the following fields:
subject: A template string for the subject of the email.
text: A template string for the plaintext content of the email.
html: A template string for the HTML content of the email.
amp: A template string for the AMP4EMAIL content of the email.
attachments: An array of attachments with template strings as values; Nodemailer options supported: utf-8 string, custom content type, URL, encoded string, data URI, and pre-generated MIME node (be aware that your email has no access to the cloud server's file system).
An example template might have an ID of following and content like:
{subject:"@{{username}} is now following you!",html:"Just writing to let you know that <code>@{{username}}</code> ({{name}}) is now following you.",attachments:[{filename:"{{username}}.jpg",path:"{{imagePath}}"}]}
Send emails using templates
To deliver email using templates, when adding documents to your mail collection,
include a template field with name and data properties. For example,
using our following template from above:
You can compose templates using reusable partials
by specifying {partial: true} in the template document. Each of the standard
data fields (subject, html, text, and amp) will be defined as a partial
used only in its own environment. For example, a partial called footer might
have data like:
{partial:true,html:"<p>This mail was sent by ExampleApp, Inc. <a href='https://example.com/unsubscribe'>Unsubscribe</a></p>",text:"This mail was sent by ExampleApp, Inc. Unsubscribe here: https://example.com/unsubscribe"}
In another template, include the partial by referencing its name (document ID):
<p>This is my main template content, but it will use a common footer.</p>
{{> footer }}
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Missing the information I need","missingTheInformationINeed","thumb-down"],["Too complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-28 UTC."],[],[],null,["\u003cbr /\u003e\n\nIf you specified a \"Templates collection\" parameter during configuration of the\nextension, you can create and manage [Handlebars templates](https://handlebarsjs.com/)\ntemplates for your emails.\n\nTemplate collection structure\n\nGive each document a memorable ID that you use as the *template name* in the\ndocuments you write to your templates collection.\n\nThe template document can include any of the following fields:\n\n- **subject:** A template string for the subject of the email.\n- **text:** A template string for the plaintext content of the email.\n- **html:** A template string for the HTML content of the email.\n- **amp:** A template string for the [AMP4EMAIL](https://amp.dev/documentation/guides-and-tutorials/learn/email-spec/amp-email-format/) content of the email.\n- **attachments:** An array of attachments with template strings as values; [Nodemailer options](https://nodemailer.com/message/attachments/) supported: utf-8 string, custom content type, URL, encoded string, data URI, and pre-generated MIME node (be aware that your email has no access to the cloud server's file system).\n\nAn example template might have an ID of `following` and content like: \n\n {\n subject: \"@{{username}} is now following you!\",\n html: \"Just writing to let you know that \u003ccode\u003e@{{username}}\u003c/code\u003e ({{name}}) is now following you.\",\n attachments: [\n {\n filename: \"{{username}}.jpg\",\n path: \"{{imagePath}}\"\n }\n ]\n }\n\nSend emails using templates\n\nTo deliver email using templates, when adding documents to your mail collection,\ninclude a `template` field with `name` and `data` properties. For example,\nusing our `following` template from above: \n\n admin\n .firestore()\n .collection(\"MAIL_COLLECTION\")\n .add({\n toUids: [\"abc123\"],\n template: {\n name: \"following\",\n data: {\n username: \"ada\",\n name: \"Ada Lovelace\",\n imagePath: \"https://example.com/path/to/file/image-name.jpg\"\n },\n },\n });\n\nTemplate Partials\n\nYou can compose templates using reusable [partials](https://handlebarsjs.com/guide/partials.html)\nby specifying `{partial: true}` in the template document. Each of the standard\ndata fields (`subject`, `html`, `text`, and `amp`) will be defined as a partial\nused only in its own environment. For example, a partial called `footer` might\nhave data like: \n\n {\n partial: true,\n html: \"\u003cp\u003eThis mail was sent by ExampleApp, Inc. \u003ca href='https://example.com/unsubscribe'\u003eUnsubscribe\u003c/a\u003e\u003c/p\u003e\",\n text: \"This mail was sent by ExampleApp, Inc. Unsubscribe here: https://example.com/unsubscribe\"\n }\n\nIn another template, include the partial by referencing its name (document ID): \n\n \u003cp\u003eThis is my main template content, but it will use a common footer.\u003c/p\u003e\n\n {{\u003e footer }}"]]