Backbone Queues

FIFO message queues. Push from anywhere; process messages with a queue-triggered function:

drift.Backbone.Queue("orders").Push(map[string]any{"item": "widget", "qty": 3})

A message body must be a JSON object. A bare string, number or array is rejected with 400 queue and body required. Queue names take alphanumerics plus ., _ and -, first character alphanumeric, up to 255 bytes. A push past the queue's depth answers 429; depths are set in the slice's shape.

drift backbone queue push orders '{"item":"widget","qty":3}'
drift backbone queue peek orders     # look without removing
drift backbone queue pop  orders     # take the next message
drift backbone queue len  orders
drift backbone queue drop orders     # delete the queue and every message in it

Queue-triggered functions

Naming a function queue:orders in the Driftfile binds it to that queue; see Atomic triggers. A background poller pops the queue every 500 ms and invokes the function once per message.

The function receives the message's inner body object, not the {id, body, timestamp} envelope that queue peek and queue pop return. Read your own fields straight off the payload.

Retries and the dead-letter queue

An invocation that fails puts the message back with a _drift_retries counter. After three attempts the message moves to a queue named <queue>-dlq, created on the first dead letter. It is an ordinary queue, so inspect and drain it like any other:

drift backbone queue len  orders-dlq
drift backbone queue peek orders-dlq
drift backbone queue pop  orders-dlq