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Alert Connector

Overview

Section titled “Overview”

The Alert connector sends notifications when conditions are met.

Connector Type: MeddleAlert

Notification Types: Email

Configuration

Section titled “Configuration”
{
  "type": "MeddleAlert",
  "config": {
    "name": "High Temperature Alert",
    "condition": "temperature > 80",
    "minDuration": 10,
    "cooldown": 300,
    "notification": {
      "type": "Email",
      "smtpHost": "smtp.example.com",
      "smtpPort": 587,
      "smtpUser": "alerts@example.com",
      "smtpPass": "password",
      "fromEmail": "alerts@example.com",
      "toEmails": ["operator@example.com", "manager@example.com"],
      "subject": "Temperature Alert",
      "body": "Temperature exceeded threshold"
    }
  }
}

Configuration Parameters

Section titled “Configuration Parameters”
  • name: Alert name for identification
  • condition: MXL expression for trigger condition
  • minDuration: Minimum seconds condition must be true before alerting
  • cooldown: Seconds to wait before sending another alert
  • notification: Notification configuration

Email Notification

Section titled “Email Notification”
  • type: "Email"
  • smtpHost: SMTP server hostname
  • smtpPort: SMTP server port (typically 587 or 465)
  • smtpUser: SMTP username
  • smtpPass: SMTP password
  • fromEmail: Sender email address
  • toEmails: Array of recipient email addresses
  • subject: Email subject
  • body: Email body text

MXL Conditions

Section titled “MXL Conditions”

Use MXL expressions for conditions:

temperature > 80
pressure < 10
temperature > 80 && pressure < 10
humidity > 60 || temperature > 25
status == "error"

See MXL Reference for complete syntax.

Min Duration

Section titled “Min Duration”

Prevents false alarms by requiring condition to be true for a minimum duration:

{
  "minDuration": 10
}

Condition must be true for 10 seconds before alert is sent.

Cooldown

Section titled “Cooldown”

Prevents alert spam by waiting between notifications:

{
  "cooldown": 300
}

After sending an alert, waits 300 seconds (5 minutes) before sending another.

Use Cases

Section titled “Use Cases”

1. Temperature Monitoring

Section titled “1. Temperature Monitoring”
{
  "type": "MeddleAlert",
  "config": {
    "name": "Freezer Temperature Alert",
    "condition": "temperature > -10",
    "minDuration": 30,
    "cooldown": 600,
    "notification": {
      "type": "Email",
      "smtpHost": "smtp.gmail.com",
      "smtpPort": 587,
      "smtpUser": "alerts@company.com",
      "smtpPass": "app-password",
      "fromEmail": "alerts@company.com",
      "toEmails": ["maintenance@company.com"],
      "subject": "Freezer Temperature Warning",
      "body": "Freezer temperature is above -10°C"
    }
  }
}

2. Equipment Failure

Section titled “2. Equipment Failure”
{
  "type": "MeddleAlert",
  "config": {
    "name": "Machine Stopped",
    "condition": "status == \"stopped\" && runtime > 0",
    "minDuration": 60,
    "cooldown": 1800,
    "notification": {
      "type": "Email",
      "smtpHost": "smtp.example.com",
      "smtpPort": 587,
      "smtpUser": "alerts@factory.com",
      "smtpPass": "password",
      "fromEmail": "alerts@factory.com",
      "toEmails": ["supervisor@factory.com", "maintenance@factory.com"],
      "subject": "Machine Stopped Alert",
      "body": "Production machine has stopped unexpectedly"
    }
  }
}

3. Multiple Conditions

Section titled “3. Multiple Conditions”
{
  "type": "MeddleAlert",
  "config": {
    "name": "Critical Process Alert",
    "condition": "temperature > 100 || pressure > 150 || vibration > 5",
    "minDuration": 5,
    "cooldown": 300,
    "notification": {
      "type": "Email",
      "smtpHost": "smtp.example.com",
      "smtpPort": 587,
      "smtpUser": "critical@factory.com",
      "smtpPass": "password",
      "fromEmail": "critical@factory.com",
      "toEmails": ["emergency@factory.com"],
      "subject": "CRITICAL: Process Alert",
      "body": "Critical process parameters exceeded"
    }
  }
}

SMTP Configuration

Section titled “SMTP Configuration”

Gmail

Section titled “Gmail”
{
  "smtpHost": "smtp.gmail.com",
  "smtpPort": 587,
  "smtpUser": "your-email@gmail.com",
  "smtpPass": "app-specific-password"
}

Note: Use App Passwords for Gmail.

Office 365

Section titled “Office 365”
{
  "smtpHost": "smtp.office365.com",
  "smtpPort": 587,
  "smtpUser": "your-email@company.com",
  "smtpPass": "your-password"
}

Custom SMTP

Section titled “Custom SMTP”
{
  "smtpHost": "mail.example.com",
  "smtpPort": 587,
  "smtpUser": "alerts@example.com",
  "smtpPass": "password"
}

Best Practices

Section titled “Best Practices”
  1. Set appropriate minDuration - Avoid false alarms
  2. Use reasonable cooldown - Prevent alert fatigue
  3. Test SMTP settings - Verify emails are delivered
  4. Use descriptive names - Identify alerts easily
  5. Include context in body - Make alerts actionable

Troubleshooting

Section titled “Troubleshooting”

Emails Not Sending

Section titled “Emails Not Sending”
  • Verify SMTP credentials
  • Check SMTP host and port
  • Ensure firewall allows SMTP traffic
  • Test SMTP connection separately
  • Check spam folder

Too Many Alerts

Section titled “Too Many Alerts”
  • Increase minDuration
  • Increase cooldown
  • Refine condition to be more specific

Missing Alerts

Section titled “Missing Alerts”
  • Decrease minDuration
  • Check condition logic
  • Verify data is flowing through connector
Section titled “Related Connectors”