Configure Queues

Cloudflare Queues can be configured using Wrangler, the command-line interface for Cloudflare's Developer Platform, which includes Workers, R2, and other developer products.

Each Worker has a wrangler.toml / wrangler.json file that specifies environment variables, triggers, and resources, such as a Queue. To enable Worker-to-resource communication, you must set up a binding in your Worker project's Wrangler file.

Use the options below to configure your queue.

Note

Below are options for Queues, refer to the Wrangler documentation for a full reference of the wrangler.toml / wrangler.json file.

Producer

A producer is a Cloudflare Worker that writes to one or more queues. A producer can accept messages over HTTP, asynchronously write messages when handling requests, and/or write to a queue from within a Durable Object. Any Worker can write to a queue.

To produce to a queue, set up a binding in your Wrangler file. These options should be used when a Worker wants to send messages to a queue.

wrangler.json

{
  "queues": {
    "producers": [
      {
        "queue": "my-queue",
        "binding": "MY_QUEUE"
      }
    ]
  }
}

wrangler.toml

[[queues.producers]]
  queue = "my-queue"
  binding = "MY_QUEUE"

• queue string

  • The name of the Queue.

• binding string

  • The name of the binding, which is a JavaScript variable.

Consumer

Workers

To consume messages from one or more queues, set up a binding in your Wrangler file. These options should be used when a Worker wants to receive messages from a queue.

wrangler.json

{
  "queues": {
    "consumers": [
      {
        "queue": "my-queue",
        "max_batch_size": 10,
        "max_batch_timeout": 30,
        "max_retries": 10,
        "dead_letter_queue": "my-queue-dlq"
      }
    ]
  }
}

wrangler.toml

[[queues.consumers]]
  queue = "my-queue"
  max_batch_size = 10
  max_batch_timeout = 30
  max_retries = 10
  dead_letter_queue = "my-queue-dlq"

Refer to Limits to review the maximum values for each of these options.

• queue string

  • The name of the Queue.

• max_batch_size number optional

  • The maximum number of messages allowed in each batch.
  • Defaults to 10 messages.

• max_batch_timeout number optional

  • The maximum number of seconds to wait until a batch is full.
  • Defaults to 5 seconds.

• max_retries number optional

  • The maximum number of retries for a message, if it fails or retryAll() is invoked.
  • Defaults to 3 retries.

• dead_letter_queue string optional

  • The name of another Queue to send a message if it fails processing at least max_retries times.
  • If a dead_letter_queue is not defined, messages that repeatedly fail processing will eventually be discarded.
  • If there is no Queue with the specified name, it will be created automatically.

• max_concurrency number optional

  • The maximum number of concurrent consumers allowed to run at once. Leaving this unset will mean that the number of invocations will scale to the currently supported maximum.
  • Refer to Consumer concurrency for more information on how consumers autoscale, particularly when messages are retried.

Pull-based

A queue can have a HTTP-based consumer that pulls from the queue. This consumer can be any HTTP-speaking service that can communicate over the Internet. Review Pull consumers to learn how to configure a pull-based consumer.