Email Notifications

Dagu provides built-in email notifications for workflow events and errors.

SMTP Configuration

Global Configuration

Set up SMTP settings in your Dagu configuration:

# ~/.config/dagu/config.yaml
smtp:
  host: smtp.gmail.com
  port: "587"
  username: [email protected]
  password: app-specific-password
  
errorMail:
  from: [email protected]
  to: [email protected]
  prefix: "[Dagu Alert]"
  attachLogs: true

Environment Variables

Configure SMTP via environment:

export DAGU_SMTP_HOST=smtp.gmail.com
export DAGU_SMTP_PORT=587
export DAGU_SMTP_USERNAME=[email protected]
export DAGU_SMTP_PASSWORD=secret-password

export DAGU_ERROR_MAIL_FROM=[email protected]
export DAGU_ERROR_MAIL_TO=[email protected]
export DAGU_ERROR_MAIL_PREFIX="[Alert]"

DAG-Level Configuration

Override global settings per DAG:

# my-dag.yaml
smtp:
  host: smtp.company.com
  port: "465"
  username: ${SMTP_USER}
  password: ${SMTP_PASS}

errorMail:
  from: [email protected]
  to: 
    - [email protected]
    - [email protected]
  prefix: "[CRITICAL]"
  attachLogs: true

mailOn:
  success: true
  failure: true

Email Triggers

Success/Failure Emails

mailOn:
  success: true    # Email on successful completion
  failure: true    # Email on failure

Step-Level Errors

steps:
  - name: critical-step
    command: process_critical_data.sh
    mailOnError: true  # Email if this step fails

Mail Executor

Send custom emails as workflow steps:

steps:
  - name: send report
    executor:
      type: mail
      config:
        to: 
          - [email protected]
          - [email protected]
        from: [email protected]
        subject: "Daily Report - ${TODAY}"
        message: |
          Daily processing report for ${TODAY}
          
          Summary:
          - Records processed: ${RECORD_COUNT}
          - Success rate: ${SUCCESS_RATE}%
          - Processing time: ${DURATION}
          
          See attached files for details.
        attachments:
          - /reports/daily-${TODAY}.pdf
          - /reports/summary-${TODAY}.csv
          - ${DAG_RUN_LOG_FILE}

Email Templates

Processing Report

steps:
  - name: generate report
    command: generate_report.py
    output: REPORT_PATH
  
  - name: email report
    executor:
      type: mail
      config:
        to: [email protected]
        subject: "Processing Report - ${DAG_NAME}"
        message: |
          Automated Report Generated
          
          DAG: ${DAG_NAME}
          Run ID: ${DAG_RUN_ID}
          Status: Completed
          Time: $(date)
          
          Report available at: ${REPORT_PATH}
        attachments:
          - ${REPORT_PATH}

Error Notification

handlerOn:
  failure:
    executor:
      type: mail
      config:
        to: 
          - [email protected]
          - [email protected]
        from: [email protected]
        subject: "⚠️ DAG Failed: ${DAG_NAME}"
        message: |
          DAG Execution Failed
          
          Details:
          - DAG: ${DAG_NAME}
          - Run ID: ${DAG_RUN_ID}
          - Time: $(date)
          - Host: $(hostname)
          
          Error Summary:
          $(tail -20 ${DAG_RUN_LOG_FILE} | grep -i error)
          
          Full log attached.
        attachments:
          - ${DAG_RUN_LOG_FILE}

SMTP Providers

Gmail

smtp:
  host: smtp.gmail.com
  port: "587"
  username: [email protected]
  password: app-specific-password  # Use app password, not regular password

Office 365

smtp:
  host: smtp.office365.com
  port: "587"
  username: [email protected]
  password: your-password

SendGrid

smtp:
  host: smtp.sendgrid.net
  port: "587"
  username: apikey
  password: ${SENDGRID_API_KEY}

AWS SES

smtp:
  host: email-smtp.us-east-1.amazonaws.com
  port: "587"
  username: ${AWS_SES_SMTP_USERNAME}
  password: ${AWS_SES_SMTP_PASSWORD}

Advanced Configuration

Multiple Recipients

errorMail:
  to:
    - [email protected]
    - [email protected]
    - [email protected]

Conditional Recipients

steps:
  - name: check environment
    command: echo $ENVIRONMENT
    output: ENV
  
  - name: notify
    executor:
      type: mail
      config:
        to: |
          `if [ "${ENV}" = "production" ]; then
            echo "[email protected]"
          else
            echo "[email protected]"
          fi`
        subject: "Alert from ${ENV}"
        message: "Environment-specific alert"

HTML Emails

steps:
  - name: send html email
    executor:
      type: mail
      config:
        to: [email protected]
        subject: "HTML Report"
        message: |
          <html>
          <body>
            <h1>Daily Report</h1>
            <table border="1">
              <tr>
                <td>Status</td>
                <td style="color: green;">Success</td>
              </tr>
              <tr>
                <td>Records</td>
                <td>${RECORD_COUNT}</td>
              </tr>
            </table>
          </body>
          </html>
        headers:
          Content-Type: text/html