Backend indexer for exploring the Penumbra blockchain built with Rust

1. Set up Rust (1.83.0 or later)
2. Install dependencies with cargo build
3. Run the application with:

   cargo run -- \
     -s "postgresql://user:password@source-host:5432/source-db?sslmode=require" \
     -d "postgresql://user:password@dest-host:5432/dest-db" \
     --genesis-json genesis.json \
     -g "https://penumbra-1.radiantcommons.com"

You can also run the application using Docker:

docker-compose up -d

View logs:

docker-compose logs -f app

The GraphQL API is accessible at:

• GraphQL API: /graphql
• GraphQL Playground: /graphql/playground
• Public playground for testing: https://api.explorer.penumbra.zone/

The Penumbra Explorer Backend supports real-time updates via WebSocket GraphQL subscriptions. This enables live streaming of new blocks, transactions, and transaction count changes directly to subscribed clients.

Example subscriptions:

subscription {
  latestBlocks(limit: 10) {
    height
    createdAt
    transactionsCount
  }
}

subscription {
  latestTransactions(limit: 10) {
    id
    hash
    raw
  }
}

subscription {
  transactionCount {
    count
  }
}

You can try the following sample GraphQL queries in the public playground:

query {
  transaction(hash: "84A8AD3E364E1F98A7C73A5D411737F634A7802265C71A528EA9720BD2ED8095") {
    hash
    block {
      height
      createdAt
    }
    body {
      memo
      parameters {
        chainId
        fee {
          amount
        }
      }
    }
    raw
    rawJson
  }
}

query {
  block(height: 123456) {
    height
    createdAt
    transactions {
      hash
      body {
        memo
      }
    }
  }
}

• -s, --source-db-url: Source database URL (required)
• -d, --dest-db-url: Destination database URL (required)
• --genesis-json: Path to Genesis JSON file (required)
• -g, --grpc-url: gRPC endpoint URL for IBC client status checks (default: https://penumbra-1.radiantcommons.com)
• --from-height: Starting block height (optional)
• --to-height: Ending block height (optional)
• --batch-size: Batch size for processing blocks (default: 100)
• --polling-interval-ms: Polling interval in milliseconds (default: 1000)

Tests are organized by module and can be run using cargo test. Critical components have unit tests covering core functionality.

Key components with test coverage:

• Transaction queue management
• Parsing utilities
• Block and transaction processing

The project uses:

• rustfmt for formatting: cargo fmt
• Clippy for linting with strict rules: cargo clippy --all-targets --all-features --workspace -- -W clippy::pedantic -D warnings

The codebase follows Rust's naming conventions:

• snake_case for variables/functions
• CamelCase for types/traits