After youcreate and deploy your Cloud Run function,you can set your function to execute in response to various scenarios byspecifying a trigger. This page provides an overview of the triggers supportedby Cloud Run functions.

Types of triggers

By default, all functions deployed on Cloud Run areCloud Run source-deployed servicesthat have an HTTP endpoint (run.app URL). If you previously created a functionwith thegcloud functions command or theCloud Functions v2 API, by default, the functionhas acloudfunctions.net HTTP endpoint.

How your function is invoked or triggered depends on the type of function youspecify whenwriting your code.

• Event-driven triggers: Reacts to events within your Google Cloud project andcorresponds toevent-driven functions(also calledCloudEvent functions). You must use Eventarc,Google's implementation of the CloudEvents spec that supports buildingevent-driven architectures, to trigger functions in response to specifiedevents.
• HTTP triggers: Reacts to HTTP(S) requests and correspond toHTTP functions. You can use otherGoogle Cloud services (non-Eventarc) as an event provider to invoke thefunction through HTTP(S) requests.

To trigger a function to react to events within your Google Cloud project,you specify triggers as part of deploying the function in the Google Cloud consoleor after function is deployed when using the gcloud CLI.

You cannot bind the same function to more than one trigger at a time, but youcan have the same event cause multiple functions to execute by deployingmultiple functions with the same trigger settings.

• Event-driven triggers:

  • Pub/Sub events triggered by Eventarc
  • Cloud Storage events triggered by Eventarc
  • Firestore events triggered by Eventarc
  • Other event triggers
    • Supports anyevent type supported by Eventarc,including 90+ event sources using Cloud Audit Logs

• HTTP triggers:

  • Invoke with an HTTP request
  • Invoke services as part of a workflow with Workflows
  • Invoke services on a schedule with Cloud Scheduler
  • Use Cloud Tasks to execute asynchronous tasks
  • Trigger services from a Pub/Sub push subscription
    • Pub/Sub messages can be routed directly to afunction through HTTP requests or wrapped under Eventarc asan event-driven trigger.

All event-driven functions use Eventarc for event delivery.Pub/Sub triggers and Cloud Storage triggers are implemented asparticular types of Eventarc triggers.

Cloud Logging can route logs to a Pub/Sub topic, where they can thenbe consumed by Cloud Run functions. SeeConfigure and manage sinks in theCloud Logging documentation for more information.

Cloud Scheduler

You can schedule an HTTP function by creating a Cloud Scheduler jobthat triggers an action using HTTP.

You can also schedule an event-driven function when your function should be triggereddirectly in response to events within your Google Cloud project; for example, when amessage is published to a Pub/Sub topic.

Cloud Tasks

Cloud Tasks HTTP Target tasks enable you to run task handlers at anyHTTP endpoint, so an HTTP function with an HTTP trigger can be used as a taskhandler. You can also use tasks to throttle or rate-limit function invocations.SeeCreate HTTP Target tasks in theCloud Tasks documentation for more information.

Gmail

Using the GmailPush Notification API,you can send Gmail events to a Pub/Sub topic and consume themwith Cloud Run.