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createPacedMutations

function createPacedMutations<TVariables, T>(config): (variables) => Transaction<T>;

Defined in: packages/db/src/paced-mutations.ts:99

Creates a paced mutations manager with pluggable timing strategies.

This function provides a way to control when and how optimistic mutations are persisted to the backend, using strategies like debouncing, queuing, or throttling. The optimistic updates are applied immediately via onMutate, and the actual persistence is controlled by the strategy.

The returned function accepts variables of type TVariables and returns a Transaction object that can be awaited to know when persistence completes or to handle errors. The strategy owns commit(); calling it on the returned transaction throws before persistence starts. rollback() remains available. If a synchronous onMutate calls this manager again and then throws, every call merged into that pending transaction rejects together.

Type Parameters

TVariables

TVariables = unknown

T

T extends object = Record<string, unknown>

Parameters

config

PacedMutationsConfig<TVariables, T>

Configuration including onMutate, mutationFn and strategy

Returns

A function that accepts variables and returns a Transaction

(variables): Transaction<T>;

Parameters

variables

TVariables

Returns

Transaction<T>

Examples

// Debounced mutations for auto-save
const updateTodo = createPacedMutations<string>({
  onMutate: (text) => {
    // Apply optimistic update immediately
    collection.update(id, draft => { draft.text = text })
  },
  mutationFn: async ({ transaction }) => {
    await api.save(transaction.mutations)
  },
  strategy: debounceStrategy({ wait: 500 })
})

// Call with variables, returns a transaction
const tx = updateTodo('New text')

// Await persistence or handle errors
await tx.when('settled')
// Queue strategy for sequential processing
const addTodo = createPacedMutations<{ text: string }>({
  onMutate: ({ text }) => {
    collection.insert({ id: uuid(), text, completed: false })
  },
  mutationFn: async ({ transaction }) => {
    await api.save(transaction.mutations)
  },
  strategy: queueStrategy({
    wait: 200,
    addItemsTo: 'back',
    getItemsFrom: 'front'
  })
})