Triggers in Serverless Containers. Overview

Triggers are criteria that automatically launch a Serverless Containers container when met. Triggers allow you to automate your work with other Yandex Cloud services, such as Yandex Object Storage, Yandex Message Queue, and Yandex Container Registry.

The following types of triggers are available in Serverless Containers:

• Timer
• Trigger for Message Queue
• Trigger for Object Storage
• Trigger for Container Registry
• Trigger for Cloud Logging
• Trigger for Yandex IoT Core
• Trigger for budgets
• Trigger for Data Streams
• Email trigger

Each trigger type has its own conditions. For example, a trigger for Object Storage may fire when an object is created or updated. You can set some conditions in the service object settings, e.g., notification thresholds in the budget settings would act as trigger conditions for budgets.

Specifics of container invocations by triggersSpecifics of container invocations by triggers

Triggers invoke a container based on preset quotas and limits.

When invoking a container with a trigger, the following considerations apply:

• You need to configure the container to return the 2xx state code if invoked successfully. Other state codes will be interpreted as an invocation error followed by a retry attempt to invoke the container.
• Before delivering messages to the container, the trigger changes their format. Each trigger type uses a message format of its own. Read more about this in the relevant trigger description.
• The service account which will invoke the container must have the serverless-containers.containerInvoker role. Other roles required for the trigger to operate correctly depend on trigger type. Read more about this in the relevant trigger description.
• If the trigger is suspended and then restarted by the user, it will not process any events that occurred during its idle time.

Message batchingMessage batching

You can configure the following triggers to batch messages before invoking a container:

• Trigger for Message Queue
• Trigger for Cloud Logging
• Trigger for Object Storage
• Trigger for Container Registry
• Trigger for Yandex IoT Core
• Trigger for Data Streams
• Email trigger

This way you can invoke a container for a whole batch of messages rather than each message separately. Specify the following in the trigger parameters:

• Waiting time, s: Message batching time. The number of messages cannot exceed the specified batch size.
• Batch size: Number of messages for batching.

For more information about message batching, see the guides for creating the relevant trigger.

Container invocation retriesContainer invocation retries

You can configure invoking a container again if the current attempt fails. Specify the following in the trigger parameters:

• Interval: Invocation retry interval.
• Number of attempts: Number of container invocation retries before the trigger moves a message to the dead letter queue.

This setting is available for all trigger types except the trigger for Message Queue.

For more information about invocation retries, see the guide for creating the relevant trigger.

See alsoSee also

• Triggers that run a Cloud Functions function
• Triggers to send messages to WebSocket connections