Validator

The Validator is a continuous service that tests relay candidates with a live WebSocket handshake and promotes successful ones to the relay table.

Purpose

Not every URL discovered by the Seeder or Finder is an active Nostr relay. URLs may be stale, point to non-Nostr services, or be unreachable. The Validator filters candidates by attempting a real WebSocket connection and verifying that the endpoint speaks the Nostr protocol.

How It Works

1. Fetches a batch of unvalidated candidate URLs from the database.
2. For each candidate, grouped by network type (clearnet, Tor, I2P, Lokinet):
   • Opens a WebSocket connection (with appropriate proxy for overlay networks).
   • Sends a Nostr protocol handshake.
   • Verifies the response indicates a valid Nostr relay.
3. Promotes successful candidates to the relay table.
4. Marks failed candidates for retry with exponential backoff.
5. Sleeps, then repeats.

Configuration

config/services/validator.yaml

interval: 120  # seconds between cycles

processing:
  chunk_size: 100    # candidates per cycle

networks:
  clearnet:
    timeout: 15
    max_tasks: 50
  tor:
    enabled: true
    timeout: 45
    max_tasks: 10
    proxy_url: socks5://tor:9050
  i2p:
    enabled: true
    timeout: 60
    max_tasks: 5
    proxy_url: socks5://i2p:4447
  loki:
    enabled: true
    timeout: 45
    max_tasks: 5
    proxy_url: socks5://lokinet:1080

cleanup:
  enabled: false
  max_failures: 100

Usage

# Run continuously
python -m bigbrotr validator

# Run a single validation cycle
python -m bigbrotr validator --once

Metrics

The Validator exposes Prometheus metrics on port 8002:

• service_counter{name="validated"} — total relays successfully validated
• service_counter{name="failed"} — total validation failures
• service_gauge{name="candidates_pending"} — current unvalidated candidates
• cycle_duration_seconds — time per validation cycle