Documentation
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Overview ¶
Package writebehind is a typed non-blocking persistence queue: the producer (simulation loop, tick goroutine, request handler) Pushes operations into a bounded channel and never blocks on the slow downstream; a dedicated draining goroutine batches them and calls the consumer-supplied Flusher.
Backpressure policies: DropOldest / DropNewest / Block / CoalesceByKey. Defaults to DropOldest, the right call for game shard write-behind (the freshest position wins).
Index ¶
Constants ¶
This section is empty.
Variables ¶
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var ( ErrCapacityRequired = errors.New("writebehind: Capacity must be > 0") ErrFlusherRequired = errors.New("writebehind: Flusher is required") ErrCoalesceNeedsKey = errors.New("writebehind: Policy=CoalesceByKey requires KeyFunc") ErrQueueClosed = errors.New("writebehind: queue closed") ErrPushBlockTimeout = errors.New("writebehind: Push timed out waiting for capacity") )
Errors surfaced by the queue.
Functions ¶
This section is empty.
Types ¶
type Config ¶
type Config[T any] struct { Capacity int // required; > 0 BatchSize int // max items per Flush; default 100 FlushInterval time.Duration // periodic flush even when batch < BatchSize; default 1s Policy Policy // default DropOldest KeyFunc func(T) string // required when Policy == CoalesceByKey Flusher Flusher[T] // required RetryBackoff func(attempt int) time.Duration // default 100ms * 2^(attempt-1), capped 5s MaxRetries int // default 3; -1 = infinite OnDrop func(item T, reason string) }
Config configures a Queue.
type FlusherFunc ¶
FlusherFunc adapts a function to Flusher.
type Policy ¶
type Policy uint8
Policy controls behaviour when the queue is full.
const ( // DropOldest replaces the oldest queued item with the new one. DropOldest Policy = iota // DropNewest drops the incoming item without queueing it. DropNewest // Block makes Push wait until queue space is available or ctx // expires. Block // CoalesceByKey overwrites an in-queue item that shares the same // key. Requires KeyFunc. CoalesceByKey )
type Queue ¶
type Queue[T any] struct { // contains filtered or unexported fields }
Queue is a typed write-behind queue. Goroutine-safe.
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