Cloud Scheduler

Google Cloud Scheduler is a fully managed cron job service. It allows you to schedule virtually any job — including batch tasks, big data jobs, and cloud infrastructure operations — using a standard cron syntax or a human-readable schedule. Cloud Scheduler integrates with Pub/Sub, HTTP endpoints, and App Engine, making it a central component of time-based automation on Google Cloud.

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What Is Cloud Scheduler?

Cloud Scheduler replaces the need to manage a cron daemon on a server. Instead of maintaining a VM or container just to run scheduled jobs, you define schedules declaratively and Cloud Scheduler handles execution, retries, and monitoring.

Key Characteristics

Characteristic	Description
Fully managed	No servers to provision or maintain
Standard cron	Uses Unix cron syntax for schedule definitions
Multiple targets	Pub/Sub, HTTP/S, and App Engine targets
Retry support	Configurable retry policies for failed invocations
Time zones	Schedule in any IANA time zone
Monitoring	Integrated with Cloud Logging and Cloud Monitoring
Regional	Jobs run in a specific region

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Targets

Cloud Scheduler supports three target types:

HTTP Target

Send an HTTP request to any publicly reachable endpoint:

gcloud scheduler jobs create http daily-report-job \
  --location=europe-west1 \
  --schedule="0 8 * * *" \
  --time-zone="Europe/London" \
  --uri="https://my-service.run.app/generate-report" \
  --http-method=POST \
  --headers="Content-Type=application/json" \
  --message-body='{"report": "daily-sales"}' \
  --oidc-service-account-email=scheduler-invoker@my-project.iam.gserviceaccount.com

Pub/Sub Target

Publish a message to a Pub/Sub topic on a schedule:

gcloud scheduler jobs create pubsub nightly-cleanup-job \
  --location=europe-west1 \
  --schedule="0 2 * * *" \
  --time-zone="Europe/London" \
  --topic=cleanup-topic \
  --message-body='{"action": "cleanup", "target": "temp-files"}'

App Engine Target

Send a request to an App Engine service:

gcloud scheduler jobs create app-engine cache-warmup-job \
  --location=europe-west1 \
  --schedule="*/15 * * * *" \
  --service=cache-service \
  --relative-url=/warmup \
  --http-method=GET

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Cron Syntax

Cloud Scheduler uses standard Unix cron syntax with five fields:

┌───────── minute (0-59)
│ ┌─────── hour (0-23)
│ │ ┌───── day of month (1-31)
│ │ │ ┌─── month (1-12)
│ │ │ │ ┌─ day of week (0-6, Sunday=0)
│ │ │ │ │
* * * * *

Common Schedules

Schedule	Cron Expression	Description
Every minute	* * * * *	Runs every minute
Every hour	0 * * * *	Runs at the top of every hour
Daily at 8am	0 8 * * *	Runs once a day at 08:00
Weekdays at 9am	0 9 * * 1-5	Runs Monday-Friday at 09:00
First of month	0 0 1 * *	Runs at midnight on the 1st
Every 15 minutes	*/15 * * * *	Runs every 15 minutes
Every 6 hours	0 */6 * * *	Runs at 00:00, 06:00, 12:00, 18:00

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Retry Configuration

Cloud Scheduler retries failed jobs automatically:

gcloud scheduler jobs create http retry-demo-job \
  --location=europe-west1 \
  --schedule="0 */6 * * *" \
  --uri="https://my-service.run.app/process" \
  --http-method=POST \
  --max-retry-attempts=5 \
  --min-backoff=10s \
  --max-backoff=300s \
  --max-retry-duration=1800s

Setting	Description	Default
max-retry-attempts	Maximum number of retries	0 (no retries)
min-backoff	Minimum wait before first retry	5s
max-backoff	Maximum wait between retries	3600s
max-retry-duration	Maximum total time for retries	0 (unlimited)

What Counts as a Failure?