Trigger
A trigger is an event, condition, input, or schedule that causes or signals an action, process, or state transition to begin or proceed.
Practical Automation with PowerShell: Effective scripting from the console to the cloud
An automation trigger is an event, condition, or invocation that initiates an automated process or workflow.
- How it is used
- Initiates automation actions through polling, schedules, or outside events.
- How deep it goes
- Distinguishes monitors, schedules, and event invocations with timing and resource-use rationale.
- Examples
- Uses log archival, file-share monitoring, submitted-request processing, scheduled tasks, and pull-request Pester testing.
- What you can do after
- Operate/configure it by selecting a trigger type and setting schedules, monitors, or event-driven workflow starts.
GitHub Actions in Action: Continuous integration and delivery for DevOps
A workflow trigger is an event or condition that starts a GitHub Actions workflow.
- How it is used
- Starts GitHub Actions automations for repository events, manual operations, scheduled work, and release-driven deployment.
- How deep it goes
- Explains trigger categories, YAML declaration, webhook filters, manual-run constraints, and release use without enumerating every supported event.
- Examples
- Uses push and workflow_dispatch workflows, filtered documentation pushes, issue triage, and published-release deployment.
- What you can do after
- Operate/configure workflows to start on selected GitHub events, manual commands, and published releases.
Read how GitHub Actions in Action: Continuous integration and delivery for DevOps explains trigger →
MongoDB 8.0 in Action, Third Edition
A trigger is an event-driven automation mechanism that invokes an action or function when a configured event occurs.
- How it is used
- Automates server-side responses to Atlas data changes, scheduled times, or authentication events.
- How deep it goes
- Explains trigger types, event delivery, configuration controls, and scheduling, but does not detail change-stream internals.
- Examples
- Illustrates shipping-record synchronization, order-driven inventory updates, insertion-time vector enrichment, and change-event logging.
- What you can do after
- Operate/configure Atlas triggers to invoke functions for database changes or recurring tasks.
Read how MongoDB 8.0 in Action, Third Edition explains trigger →
ASP.NET Core in Action, 3e
A Quartz.NET trigger is a scheduling definition that specifies when and under what repetition rules a job executes.
- How it is used
- Schedules Quartz.NET jobs, from simple intervals to calendar-based execution windows.
- How deep it goes
- Explains schedule options, missed triggers, concurrency, persistence, and clustering without detailing every configuration setting.
- Examples
- Uses exchange-rate updates, immediate startup, five-minute repetition, and Friday 5:30 p.m. weekly execution.
- What you can do after
- Configure Quartz.NET triggers for interval, calendar, missed-execution, and clustered scheduling scenarios.
Effective Platform Engineering
A pipeline trigger is an event or condition that causes an automation pipeline to start.
- How it is used
- Starts repository automation and selects which jobs respond to particular branches, tags, or other changes.
- How deep it goes
- Explains repository events, schedules, cross-repository risks, branch and tag filters, and reusable YAML conditions.
- Examples
- Uses repository changes, nightly builds, tag creation, and a CircleCI main-branch filter as concrete trigger examples.
- What you can do after
- Operate/configure predictable pipeline starts with repository events and reusable branch or tag filters.
Data Pipelines with Apache Airflow, Second Edition
An Airflow trigger is an asynchronous Python component that waits for an external condition and signals a deferred task when the condition is met.
- How it is used
- Waits for external conditions on behalf of deferred Airflow tasks without occupying a worker slot throughout the wait.
- How deep it goes
- Explains the triggerer handoff and outlines custom serialize and asynchronous run methods, without detailing the complete polling implementation.
- Examples
- Uses FileSensorAsync and a custom ratings sensor that waits for interval-specific records before a fetch task runs.
- What you can do after
- Build it from scratch as a custom trigger paired with a deferrable sensor, or apply it via FileSensorAsync.
Read how Data Pipelines with Apache Airflow, Second Edition explains trigger →
AI for Everyday IT
A trigger is an event or condition that initiates execution of an automated workflow.
- How it is used
- Starts Teams workflows when matching email arrives or meets configured sender and folder conditions.
- How deep it goes
- Explains trigger selection through templates, sender filters, folder monitoring, and connector authorization, but not trigger internals.
- Examples
- Uses incoming-email, sender-filter, and Outlook-folder conditions in an email-sentiment workflow that posts to Teams.
- What you can do after
- Operate and configure a Teams workflow that runs only for selected incoming messages.
.NET MAUI in Action
A workflow trigger is a condition or event specification that determines when an automation workflow starts.
- How it is used
- Starts GitHub Actions workflows in response to repository events or a manual request.
- How deep it goes
- Explains event choices and branch filtering with a YAML configuration, but does not detail trigger evaluation internals.
- Examples
- Uses a build-and-deploy workflow triggered by pushes to main or workflow_dispatch.
- What you can do after
- Operate/configure GitHub Actions workflows to run automatically or manually under selected conditions.
Software Design for Python Programmers
A trigger is an actor-initiated event that starts a use case.
- How it is used
- Defines the actor action that starts each use case in a use-case description.
- How deep it goes
- Defines the starting action and its viewpoint, but does not detail implementation or event-processing internals.
- Examples
- Uses a customer pressing Search after entering target book attributes in an online catalogue form.
- What you can do after
- Evaluate which actor action initiates a use case and document it in the use-case description.
Read how Software Design for Python Programmers explains trigger →
Related concepts
- workflow definitionconfigures · A workflow definition is a declarative specification of an automated process’s tasks, their order or dependencies, and the conditions governing execution.
- SQL triggerincludes · An SQL trigger is a database routine or object that executes automatically in response to specified events on a database object.
- Atlas Functionuses · An Atlas Function is server-side JavaScript code hosted by MongoDB Atlas that controls application behavior and can access Atlas data or invoke other functions.
- webhookincludes · A webhook is an HTTP callback mechanism that sends event-related information to a configured endpoint when a specified event occurs.
- workflowconfigures · A workflow is an organized sequence of coordinated activities, tasks, or decisions through which work progresses toward an outcome.
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