huawei-cloud-functiongraph-trigger-create

Overview

This skill enables the creation and configuration of scheduled triggers (TIMER type) for Huawei Cloud FunctionGraph functions. It supports Quartz Cron expression format for flexible scheduling configurations.

The trigger allows automatic execution of serverless functions at specified time intervals, making it ideal for:

• Periodic data processing tasks
• Scheduled backup operations
• Regular monitoring and health checks
• Time-based notification systems

Prerequisites

Before using this skill, ensure the following requirements are met:

1. Python Environment: Python 3.9+ installed
2. SDK Installation: Install FunctionGraph SDK: pip install huaweicloudsdkfunctiongraph
3. Environment Variables: Configure the following environment variables:
   • HUAWEI_AK: Huawei Cloud Access Key
   • HUAWEI_SK: Huawei Cloud Secret Key
   • HUAWEI_REGION: Target region (e.g., cn-north-4)
   • HUAWEI_PROJECT_ID: Project ID
4. FunctionGraph Function: Target function must already exist in the specified region
5. Network Access: Stable network connection to Huawei Cloud API endpoints

Usage

Basic Command Structure

cd scripts
python create_trigger.py \
    --function-urn "urn:fss:cn-north-4:project_id:function:default:my-function:latest" \
    --name "daily-trigger" \
    --schedule "0 0 2 * * ?" \
    --schedule-type "Cron" \
    --status "ACTIVE"

Examples

Cron Expression Trigger

cd scripts
python create_trigger.py \
    --function-urn "urn:fss:cn-north-4:project_id:function:default:my-function:latest" \
    --name "daily-trigger" \
    --schedule "0 0 8 * * ?" \
    --schedule-type "Cron"

Fixed Rate Trigger

cd scripts
python create_trigger.py \
    --function-urn "urn:fss:cn-north-4:project_id:function:default:my-function:latest" \
    --name "every-5min" \
    --schedule "5m" \
    --schedule-type "Rate"

Cron Expression Format

FunctionGraph uses Quartz Cron format with 6 or 7 fields:

┌───────────── second (0-59)
│ ┌───────────── minute (0-59)
│ │ ┌───────────── hour (0-23)
│ │ │ ┌───────────── day of month (1-31)
│ │ │ │ ┌───────────── month (1-12)
│ │ │ │ │ ┌───────────── day of week (1-7, 1=Sunday)
│ │ │ │ │ │
* * * * * ?

For detailed Cron expression reference including special characters and common examples, see Cron Expression Reference.

Parameters Confirmation

Before creating the trigger, confirm the following parameters:

Parameter	Required	Description	Example
function_urn	Yes	Target function URN	urn:fss:cn-north-4:xxx:function:default:my-func:latest
trigger_name	Yes	Trigger name (1-64 chars)	daily-trigger
schedule	Yes	Cron expression or Rate value	0 0 2 * * ? or 5m
schedule_type	No	Cron (default) or Rate	Cron
enable_status	No	ACTIVE (default) or DISABLED	ACTIVE
user_event	No	Additional user event data	optional info

Confirmation Checklist

• Function URN is correct and function exists
• Cron expression has been validated
• Trigger name follows naming conventions
• IAM permissions are sufficient
• Region matches the function location

Output Format

Success Response

{
    "status": "success",
    "trigger_id": "timer-xxx-xxx-xxx",
    "trigger_name": "daily-trigger",
    "trigger_type": "TIMER",
    "schedule": "0 0 2 * * ?",
    "enable_status": "ACTIVE",
    "message": "Trigger created successfully"
}

Error Response

{
    "status": "failed",
    "error_code": "TriggerAlreadyExists",
    "message": "Trigger with the same name already exists"
}

For complete error codes and troubleshooting information, see Cron Expression Reference.

Verification Method

After creating the trigger, verify the configuration:

1. List Function Triggers

Navigate to FunctionGraph console → Function details → Triggers tab to view all triggers

2. Check Trigger Details

Navigate to FunctionGraph console → Function details → Triggers → View trigger details

3. Monitor Trigger Execution

Navigate to FunctionGraph console → Function details → Triggers → View execution history

Expected indicators:

• Trigger status: Active
• Next execution time: Correctly calculated
• Execution history: No failed invocations

Best Practices

Cron Expression Best Practices

1. Avoid frequent executions: Use intervals ≥ 5 minutes unless necessary
2. Consider timezone: FunctionGraph uses UTC by default
3. Use ? for unused day field: Either day-of-month or day-of-week should use ?
4. Validate before creation: Test expressions using online Cron validators

Naming Conventions

• Use descriptive names: daily-data-sync, hourly-health-check
• Follow pattern: [frequency]-[purpose]
• Maximum 64 characters
• Use lowercase with hyphens

Security Considerations

1. Least privilege: Grant minimal IAM permissions
2. Enable encryption: Use KMS for sensitive function inputs
3. Monitor executions: Set up Cloud Eye alarms for failures
4. Rate limiting: Configure appropriate retry parameters

Operational Recommendations

1. Start with disabled status for testing
2. Document trigger purpose in description field
3. Set appropriate retries for transient failures
4. Monitor first executions after enabling

Reference Documents

For detailed information, refer to:

• SDK Installation Guide
• IAM Policies
• Verification Method
• Acceptance Criteria
• Cron Expression Reference

Important Notes

Compatibility Notes

This skill is designed to work with Huawei Cloud FunctionGraph API. The tags field helps with skill discovery and categorization, while the version field follows semantic versioning for skill updates.

Limitations

1. Maximum triggers: Each function supports up to 10 triggers by default
2. Cron precision: Second-level scheduling may have minor delays
3. Timeout handling: Function timeout should be less than trigger interval
4. Cold start: First executions may have additional latency

Cost Implications

• No additional cost for trigger configuration
• Function execution billed per invocation
• Consider execution frequency for cost optimization

Common Pitfalls

1. Wrong timezone: Remember FunctionGraph uses UTC
2. Overlapping schedules: Multiple triggers may cause concurrent executions
3. Long-running functions: Ensure function completes before next trigger
4. Cron syntax errors: Validate expression format before deployment

For troubleshooting and error codes, refer to Cron Expression Reference.

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Related Skills:

• huawei-cloud-functiongraph-function-create
• huawei-cloud-functiongraph-deploy