To Email

Use this node to transform an incoming message into an email-ready SEND_EMAIL message — for example, converting a high-temperature alarm into a formatted notification email with device name and reading values substituted from message metadata and data. This node constructs the email parameters; the actual dispatch is handled by a downstream Send Email node.

All fields support templatization — use ${metadataKey} and $[dataKey] to substitute values dynamically.

• From — sender email address (e.g., alarms@yourcompany.com).

• To — comma-separated list of primary recipient addresses.
• Cc — comma-separated list of CC recipients (optional).
• Bcc — comma-separated list of BCC recipients (optional).

• Subject — email subject line. Supports templatization and date formatting (see below).
• Mail body type — how the body is rendered:
  • Plain text — body sent as-is unformatted text.
  • HTML — body rendered as HTML.
  • Use body type template — body type determined at runtime from Body type template (resolves to "true" for HTML or "false" for plain text).
• Body — main email content. Supports templatization and date formatting.

Use %d{<pattern>} to insert the message processing timestamp as a formatted date string, where <pattern> is a Java SimpleDateFormat pattern:

• Device Alert at %d{yyyy-MM-dd HH:mm:ss} → Device Alert at 2024-03-15 10:30:00

If the incoming message metadata contains emailTimezone with a valid timezone ID (e.g., Europe/Kyiv), that timezone is applied to the date formatting. Otherwise the server’s default timezone is used.

The node reads these optional metadata keys from the incoming message:

• attachments — comma-separated Blob Entity UUIDs to attach.
• reports — comma-separated report UUIDs to attach.
• images — JSON map of Content-IDs to data URLs, for embedding images in HTML: {"logo": "data:image/png;base64,..."}; reference in body as <img src="cid:logo">.

1. Receive the incoming message.
2. Substitute all template patterns in From, To, Cc, Bcc, Subject, Body, and Body type template.
3. Process %d{...} date-format patterns in Subject and Body using the message processing timestamp and emailTimezone metadata if present.
4. Check metadata for attachments, reports, and images keys and include in the output.
5. Determine the final body type (html: true/false).
6. Construct a new message of type SEND_EMAIL whose data is a JSON object containing all email fields; route via Success.

Incoming metadata: { "deviceName": "TempSensor-A1", "deviceType": "Temperature Sensor" }

Incoming data (alarm object, excerpt): { "details": { "temperatureValue": 95.5, "temperatureThreshold": 90 } }

{
  "fromTemplate": "alarms@yourcompany.com",
  "toTemplate": "example@yourcompany.com",
  "ccTemplate": null,
  "bccTemplate": null,
  "subjectTemplate": "${deviceType} - ${deviceName}: High temperature alarm",
  "mailBodyType": "false",
  "bodyTemplate": "A temperature of $[details.temperatureValue] exceeds the threshold of $[details.temperatureThreshold]."
}

Outgoing SEND_EMAIL data:

{
  "from": "alarms@yourcompany.com",
  "to": "example@yourcompany.com",
  "cc": null,
  "bcc": null,
  "subject": "Temperature Sensor - TempSensor-A1: High temperature alarm",
  "body": "A temperature of 95.5 exceeds the threshold of 90.",
  "html": false
}

Subject substituted ${deviceType} and ${deviceName} from metadata; body substituted $[details.temperatureValue] and $[details.temperatureThreshold] from data.

Configuration:

• From: no-reply@yourcompany.com — static sender address
• To: ${userEmail} — recipient resolved from message metadata at runtime
• Subject: ThingsBoard Notification — static subject line
• Mail body type: Use body type template — body type (HTML or plain text) determined at runtime from the Body type template field below
• Body type template: ${isHtml} — reads isHtml from metadata; "true" → HTML output, "false" → plain text output
• Body: HTML template below

<table class="main" style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; font-size: 14px; box-sizing: border-box; border-radius: 3px; width: 100%; background-color: #f6f6f6; margin: 0px auto;" cellspacing="0" cellpadding="0" bgcolor="#f6f6f6">
    <tbody>
    <tr style="box-sizing: border-box; margin: 0px;">
        <td class="content-wrap" style="box-sizing: border-box; vertical-align: top; margin: 0px; padding: 20px;" align="center" valign="top">
            <table style="box-sizing: border-box; border: solid 1px #e9e9e9; border-radius: 3px; margin: 0px; height: 127px; padding: 20px; background-color: #ffffff; width: 600px; max-width: 600px !important;" width="600" cellspacing="0" cellpadding="0">
                <tbody>
                <tr style="box-sizing: border-box; margin: 0px;">
                    <td class="content-block" style="color: #348eda; box-sizing: border-box; border-radius: 6px; vertical-align: top; margin: 0px; padding: 0px 0px 20px; width: 839px;" valign="top">
                        <h2>Test message using 'to email' rule node</h2>
                    </td>
                </tr>
                <tr style="box-sizing: border-box; margin: 0px;">
                    <td class="content-block" style="box-sizing: border-box; vertical-align: top; margin: 0px; padding: 0px 0px 20px; width: 600px;" valign="top"><span style="color: #000000;">This email is indicating that your outgoing mail settings were set up correctly.</span></td>
                </tr>
                <tr style="box-sizing: border-box; margin: 0px;">

Incoming:

• Metadata: { "userEmail": "johndoe@thingsboard.io", "isHtml": "true" }

Outgoing SEND_EMAIL data:

{
  "from": "no-reply@yourcompany.com",
  "to": "johndoe@thingsboard.io",
  "cc": null,
  "bcc": null,
  "subject": "ThingsBoard Notification",
  "body": "<table class=\"main\" ...>...</table>",
  "attachments": null,
  "reports": null,
  "images": null,
  "html": true
}

${userEmail} resolved to johndoe@thingsboard.io; ${isHtml} resolved to "true" → html: true in output.

{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "title": "TbMsgToEmailNodeConfiguration",
  "type": "object",
  "required": ["fromTemplate", "toTemplate", "subjectTemplate", "bodyTemplate", "mailBodyType"],
  "additionalProperties": false,
  "properties": {
    "fromTemplate": { "type": "string" },
    "toTemplate": { "type": "string" },
    "ccTemplate": { "type": "string" },
    "bccTemplate": { "type": "string" },
    "subjectTemplate": { "type": "string" },
    "bodyTemplate": { "type": "string" },
    "mailBodyType": { "type": "string", "enum": ["false", "true", "dynamic"] },
    "isHtmlTemplate": { "type": "string", "description": "Template for dynamic body type; resolves to 'true' or 'false'." }
  }
}