snapshot_bootstrapper

Snapshot Bootstrapper Module

The snapshot bootstrapper module downloads and processes a Cardano ledger snapshot to initialize system state before processing the live chain.

Overview

This module:

1. Waits for genesis bootstrap completion
2. Downloads a compressed snapshot file from a configured URL
3. Streams and publishes snapshot data (UTXOs, pools, accounts, DReps, proposals)
4. Signals completion to allow chain synchronization to begin

Messages

The snapshot bootstrapper:

• Subscribes to cardano.sequence.bootstrapped - Waits for genesis completion
• Publishes to cardano.snapshot - Streams snapshot data during processing
• Publishes to cardano.sync.command - Signals completion with point to begin sync from

Default Configuration

[global.startup]
network-name = "mainnet"

[module.snapshot-bootstrapper]

# Target epoch to download and process.
epoch = 500

# Data directory
data-dir = "./data"

# Message topics
snapshot-topic = "cardano.snapshot"
bootstrapped-subscribe-topic = "cardano.sequence.bootstrapped"
sync-command-topic = "cardano.sync.command"

# Download settings
[download]
timeout-secs = 300
connect-timeout-secs = 30
progress-log-interval = 200

Directory Structure

The module expects the following files in {data-dir}/{network}/:

• snapshots.json - Snapshot metadata including download URLs

The snapshot file is downloaded to {data-dir}/{network}/{point}.cbor.

Example config.json

{
  "snapshot": 500,
  "points": [
    {
      "epoch": 500,
      "id": "abc123...",
      "slot": 12345678
    }
  ]
}