Creating a trigger for Message Queue that sends messages to a Serverless Containers container

If you do not have the Yandex Cloud CLI yet, install and initialize it.

The folder specified when creating the CLI profile is used by default. To change the default folder, use the yc config set folder-id <folder_ID> command. You can specify a different folder using the --folder-name or --folder-id parameter.

To create a trigger that invokes a container, run this command:

yc serverless trigger create message-queue \
  --name <trigger_name> \
  --queue <queue_ID> \
  --queue-service-account-id <service_account_ID> \
  --invoke-container-id <container_ID> \
  --invoke-container-service-account-id <service_account_ID> \
  --batch-size <message_group_size> \
  --batch-cutoff <maximum_timeout>

Where:

• --name: Trigger name.

• --queue: Queue ID.

  To find out the queue ID:

  1. In the management console, select the folder containing the queue.
  2. Select Message Queue.
  3. Select the desired queue.
  4. You can see the queue ID under General information in the ARN field.

• --invoke-container-id: Container ID.

• --queue-service-account-id: ID of the service account with permissions to read messages from the queue.

• --invoke-container-service-account-id: ID of the service account with permissions to invoke the container.

• --batch-size: Message batch size. This is an optional parameter. The values may range from 1 to 1,000. The default value is 1.

• --batch-cutoff: Maximum wait time. This is an optional parameter. The values may range from 0 to 20 seconds. The default value is 10 seconds. The trigger groups messages for a period not exceeding batch-cutoff and sends them to a container. The number of messages cannot exceed batch-size.

Result:

id: a1s5msktijh2********
folder_id: b1gmit33hgh2********
created_at: "2022-10-24T15:19:15.353909857Z"
name: ymq-trigger
rule:
  message_queue:
    queue_id: yrn:yc:ymq:ru-central1:b1gmit33ngh2********:my-mq
    service_account_id: bfbqqeo6jkh2********
    batch_settings:
      size: "1"
      cutoff: 10s
    invoke_container:
      container_id: bba5jb38o8h2********
      service_account_id: bfbqqeo6jkh2********
status: ACTIVE

With Terraform, you can quickly create a cloud infrastructure in Yandex Cloud and manage it using configuration files. These files store the infrastructure description written in HashiCorp Configuration Language (HCL). If you change the configuration files, Terraform automatically detects which part of your configuration is already deployed, and what should be added or removed.

Terraform is distributed under the Business Source License. The Yandex Cloud provider for Terraform is distributed under the MPL-2.0 license.

For more information about the provider resources, see the documentation on the Terraform website or mirror website.

If you do not have Terraform yet, install it and configure its Yandex Cloud provider.

To create a trigger for Message Queue:

1. In the configuration file, describe the trigger parameters:

   resource "yandex_function_trigger" "my_trigger" {
     name = "<trigger_name>"
     container {
       id                 = "<container_ID>"
       service_account_id = "<service_account_ID>"
     }
     message_queue {
       queue_id           = "<queue_ID>"
       service_account_id = "<service_account_ID>"
       batch_cutoff       = "<maximum_timeout>"
       batch_size         = "<message_group_size>"
     }
   }
   

   Where:

   • name: Trigger name. The name format is as follows:

     • It must be from 2 to 63 characters long.
     • It may contain lowercase Latin letters, numbers, and hyphens.
     • It must start with a letter and cannot end with a hyphen.

   • container: Container parameters:

     • id: Container ID.
     • service_account_id: ID of the service account with rights to invoke the container.

   • message_queue: Trigger parameters:

     • queue_id: Queue ID

       To find out the queue ID:

       1. In the management console, select the folder containing the queue.
       2. Select Message Queue.
       3. Select the desired queue.
       4. You can see the queue ID under General information in the ARN field.

     • service_account_id: ID of the service account with permissions to read messages from the queue.

     • batch_cutoff: Maximum wait time. This is an optional parameter. The values may range from 0 to 20 seconds. The default value is 10 seconds. The trigger groups messages for a period not exceeding batch-cutoff and sends them to a container. The number of messages cannot exceed batch-size.

     • batch_size: Message batch size. This is an optional parameter. The values may range from 1 to 1,000. The default value is 1.

   For more information about the yandex_function_trigger resource parameters, see the provider documentation.

2. Create resources:

   1. In the terminal, change to the folder where you edited the configuration file.

   2. Make sure the configuration file is correct using the command:

      terraform validate
      

      If the configuration is correct, the following message is returned:

      Success! The configuration is valid.
      

   3. Run the command:

      terraform plan
      

      The terminal will display a list of resources with parameters. No changes are made at this step. If the configuration contains errors, Terraform will point them out.

   4. Apply the configuration changes:

      terraform apply
      

   5. Confirm the changes: type yes in the terminal and press Enter.

   Terraform will create all the required resources. You can check the new resources using the management console or this CLI command:

   yc serverless trigger list
   

To create a trigger for Message Queue, use the create REST API method for the Trigger resource or the TriggerService/Create gRPC API call.

Check that the number of enqueued messages is decreasing. To do this, view the queue statistics:

1. In the management console, open Message Queue.
2. Select the queue that you created the trigger for.
3. Go to Monitoring. Check the Messages in the queue chart.