An automation trigger is the event or condition that starts automated actions. It belongs with the automation goal, the actions themselves, and maintainability: choose the trigger according to what must happen, how often it must happen, and the cost of checking for it. section 1.2
Triggers are either polling or event-based. Polling checks an endpoint for a condition; event-based triggering begins when an outside interaction occurs. The distinction determines whether the automation waits and checks, runs on a timetable, or responds immediately to an invocation. section 1.2.2
Use the trigger pattern that matches the operational need:
- Use a monitor to repeatedly look for a condition, such as an FTP upload, a new email, or a running service. Run it continuously or at an interval chosen to avoid needless resource use. section 1.2.2
- Use a schedule when work should run every time at a defined time or recurrence, without first checking a condition; file cleanup, synchronization, and routine maintenance fit this pattern. section 1.2.2
- Use an event trigger when an HTTP webhook, another automation, a service-desk request, a button, or a command-shell invocation should initiate work. section 1.2.2
Keep the automation logic independent of its trigger where possible. A script that processes submitted requests can be started by Task Scheduler or Cron polling for entries, or by SharePoint-connected webhooks, Azure Automation, or Azure Functions; the processing script can remain the same while the initiating platform changes. section 11.3 section 1.4.3
Scheduled log archival
A web server whose audit logs fill its drives can run a scheduled task to find logs older than 30 days, compress them, and move them to long-term storage. In Windows Task Scheduler, create a daily trigger, point the action at the PowerShell script with its parameters, then review execution history and Event Viewer logs for failures. section 1.2 section 3.2.1
Pull-request test trigger
A GitHub workflow can trigger Pester tests when a pull request is opened or reopened. The trigger is declared with YAML's on key; a job then checks out repository code and runs the PowerShell test script on a selected operating-system image. section 14.2.1
name: PoshAutomator Pester Tests
on:
pull_request:
types: [opened, reopened]
This YAML fragment shows a workflow name and an on trigger that starts the workflow for newly opened or reopened pull requests. section 14.2.1
