queueStrategy

function queueStrategy(options?): QueueStrategy;

Defined in: packages/db/src/strategies/queueStrategy.ts:57

Creates a queue strategy that processes admitted mutations in order with proper serialization.

Unlike other strategies that may drop executions, queue ensures every admitted mutation is attempted sequentially. Each transaction commit completes before the next one starts. Useful when data consistency is critical and every admitted operation must be attempted in order. When a bounded queue is full, the returned transaction fails and its optimistic mutation rolls back. Cleanup stops new admission. The existing timer drains admitted waiting work at its configured pace behind earlier writes. Cleanup does not wait for settlement.

Error handling behavior:

• If a mutation fails, it is NOT automatically retried - the transaction transitions to "failed" state
• Failed mutations surface their error via transaction.when('settled') (which will reject)
• Subsequent mutations continue processing - a single failure does not block the queue
• Each mutation is independent; there is no all-or-nothing transaction semantics

Parameters

options?

QueueStrategyOptions

Configuration for queue behavior (FIFO/LIFO, timing, size limits)

Returns

QueueStrategy

A queue strategy instance

Examples

// FIFO queue - process in order received
const mutate = usePacedMutations({
  mutationFn: async ({ transaction }) => {
    await api.save(transaction.mutations)
  },
  strategy: queueStrategy({
    wait: 200,
    addItemsTo: 'back',
    getItemsFrom: 'front'
  })
})

// LIFO queue - process most recent first
const mutate = usePacedMutations({
  mutationFn: async ({ transaction }) => {
    await api.save(transaction.mutations)
  },
  strategy: queueStrategy({
    wait: 200,
    addItemsTo: 'back',
    getItemsFrom: 'back'
  })
})