Structure

BlockchainSync

Drives a ChainstateManager from a BlockSource toward the source’s tip, emitting typed progress updates as blocks are validated.

struct BlockchainSync

Mentioned In

Overview

Shape follows Apple’s CLLocationUpdate.liveUpdates(_:) pattern — a value-type configuration exposing a typed AsyncSequence of progress snapshots. Cancel by breaking the for await loop or cancelling the enclosing Task; the iterator’s cleanup calls interrupt().

let sync = BlockchainSync(manager: manager, source: source, context: context)
for await update in sync.updates() {
    print("\(update.tip.height)/\(update.remoteTip.height) — \(update.state)")
}

Error delivery

Failures arrive as Update(state: .failed(reason), ...) final elements; the sequence is non-throwing. Cancellation ends the sequence silently (no final Update — cancel is a clean lifecycle event, not a failure).

Concurrency

The sync loop runs on a background Task owned by the sequence iterator. Block processing (ChainstateManager.processBlock) runs inline — fast for regtest/signet, slow-but-acceptable for mainnet IBD. UI consumers observe progress either through this sequence or progress (a Foundation.Progress bound to the same state for SwiftUI.ProgressView and BGContinuedProcessingTask.progress integration).

Topics

Structures

struct Update
A single snapshot of sync progress — the element type emitted by BlockchainSync.Updates.
struct Updates
A single-consumer AsyncSequence of BlockchainSync.Update values emitted as the sync engine drives the chainstate forward.

Initializers

init(manager: ChainstateManager, source: any BlockSource, context: Context)
Create a new sync engine.

Instance Properties

var progress: Progress
Foundation.Progress tracking completedUnitCount = local tip height and totalUnitCount = remote tip height.

Instance Methods

func updates() -> BlockchainSync.Updates
Starts the sync and returns a typed async sequence of progress snapshots.