gweidmann/seq-app-htmlemail

Plug-in apps that act on event streams in the Seq log server

Seq.App.EmailPlus

Send log events and alerts as HTML email messages when they arrive at Seq.

HTML email templates

The app uses Handlebars.Net for email templating. Check out the Handlebars Guide for information on the Handlebars syntax.

Event types and properties

All templates can access the following special properties:

• $DateTimeFormat — the date/time format string defined in the app's settings
• $EventType — the numeric event type assigned to the event
• $EventUri — a link to the event in the Seq UI (not valid for alerts)
• $Exception — the exception associated with the event, if any
• $Id — the Seq event id
• $Instance — the Seq server's instance name, if any
• $Level — the event's level as a string
• $LocalTimestamp — the timestamp of the event, in the server's time zone (deprecated)
• $Message — the event's fully-rendered message
• $MessageTemplate — the event's message template
• $Properties — a dictionary containing all first-class event properties (see below)
• $ServerUri — the Seq server's base URL
• $TimeZoneName — the time zone name defined in the app's settings
• $UtcTimestamp — the timestamp of the event

The event's first-class properties do not use prefixed $ names, so if an event carries a RequestId property, this is accessed in the template as {{RequestId}}, not {{$RequestId}}.

Notifications for Alerts can use the properties listed in the Seq documentation.

Built-in helper functions

The app makes the following helper functions available in templates.

Name	Description	Example usage
datetime	Format a date time, optionally specifying a time zone	{{datetime $SliceStart 'o' 'Australia/Brisbane'}}
if_eq	Compare two values for equality and optionally execute a specified block	{{#if_eq $Level 'Error'}} Oops! {{/if_eq}}
pretty	Pretty-print a value, converting arrays and objects to JSON	{{pretty Results}}
substring	Compute a substring given start index and optional length	{{substring Uri 0 5}}

Helpers are defined here.

Other Seq apps

This repository originally included the following apps from Datalust, each now in their own dedicated repositories:

• File Archive - write incoming events into a set of rolling text files
• First of Type - raise an event the first time a new event type is seen
• Replication - forward incoming events to another Seq server
• Thresholds - raise an event if the frequency of matched events exceeds a threshold
• Digest Email - send multiple events as a single HTML email
• Health Check Input - periodically GET an HTTP resource and write response metrics to Seq
• GELF Input - ingest events GELF format over TCP or UDP
• JSON Archive - write incoming events into a set of rolling files, in JSON format
• RabbitMQ Input - ingest events from RabbitMQ
• Syslog Input - ingest syslog events over UDP