Mempool Integration with Bitcoin Node

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Intro §

Mempool is a real-time web interface for visualizing Bitcoin’s mempool, where unconfirmed transactions are stored. It provides detailed insights into transaction fees, mempool congestion, and network activity. Users can view transaction history, fee estimates, and the current state of the Bitcoin network.

Self-hosting a mempool site alongside a Bitcoin node enhances your privacy by keeping transaction data within your control and not relying on third-party servers.

Additionally, operating your own instance eliminates dependency on external services, ensuring continuous access and reliability even if external servers experience issues or downtime.

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Prerequisite §

Before we start, ensure you have the following prerequisites:

• A server or machine with Docker installed.
• Basic understanding of Docker concepts such as containers, images, and volumes.
• Docker Compose.
• A Bitcoin node with an Electrum server, see 15-zero-to-bitcoin-node to see how to install both.
• A Caddy server, see 01-caddy-in-docker or 09-caddy-wildcard-certificates

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Configuration §

Networking §

Assuming you have followed the previous guide 15-zero-to-bitcoin-node and want to use a Caddy reverse proxy (see 01-caddy-in-docker or 09-caddy-wildcard-certificates) to access the Mempool web server, the network configuration should be as follows:

The mempool-api service is on the bitcoin network to access both Elects and Bitcoin node and in the internal network to access the mempool-db service.

The mempool-web is on the caddy network to allow Caddy to reverse proxy to the server, and on the internal network to access the mempool-api backend.

The mempool-db only needs access to the mempool-api and mempool-web, so it is configured to use only the internal network.

Docker compose file §

Create a folder mempool:

mkdir mempool && cd mempool

Create a docker-compose.yml file with the content:

services:
  web:
    environment:
      FRONTEND_HTTP_PORT: "8080"
      BACKEND_MAINNET_HTTP_HOST: "api"
    image: mempool/frontend:latest
    user: "1000:1000"
    restart: unless-stopped
    stop_grace_period: 1m
    command: "./wait-for db:3306 --timeout=720 -- nginx -g 'daemon off;'"
    networks:
      - internal
      - caddy
 
  api:
    environment:
      MEMPOOL_BACKEND: "electrum"
      ELECTRUM_HOST: "192.168.10.3"
      ELECTRUM_PORT: "50001"
      ELECTRUM_TLS_ENABLED: "false"
      CORE_RPC_HOST: "192.168.10.2"
      CORE_RPC_PORT: "8332"
      CORE_RPC_USERNAME: "bitcoin_rpc_user"
      CORE_RPC_PASSWORD: "bitcoin_rpc_password"
      DATABASE_ENABLED: "true"
      DATABASE_HOST: "db"
      DATABASE_DATABASE: "mempool"
      DATABASE_USERNAME: "mempool"
      DATABASE_PASSWORD: "mempool"
      STATISTICS_ENABLED: "true"
    image: mempool/backend:latest
    user: "1000:1000"
    restart: on-failure
    stop_grace_period: 1m
    command: "./wait-for-it.sh db:3306 --timeout=720 --strict -- ./start.sh"
    networks:
      internal:
      bitcoin-network:
        ipv4_address: 192.168.10.4
    volumes:
      - ./data:/backend/cache
 
  db:
    environment:
      MYSQL_DATABASE: "mempool"
      MYSQL_USER: "mempool"
      MYSQL_PASSWORD: "mempool"
      MYSQL_ROOT_PASSWORD: "admin"
    image: mariadb:10.5.21
    user: "1000:1000"
    restart: unless-stopped
    stop_grace_period: 1m
    networks:
      - internal
    volumes:
      - ./mysql/data:/var/lib/mysql
 
networks:
  caddy:
    name: caddy
    external: true
  bitcoin-network:
    name: bitcoin-network
    external: true
  internal: {}

Note

Be sure to replace bitcoin_rpc_user and bitcoin_rpc_password with your actual credentials.

Start the service using the command:

docker compose up -d

Caddy reverse proxy §

Add the Caddy configuration:

mempool.domain.name {
    reverse_proxy http://mempool-web-1:8080
}

or if you are using wildcard certificates as described in the 09-caddy-wildcard-certificates guide:

@mempool host mempool.domain.name
handle @mempool {
    reverse_proxy http://mempool-web-1:8080
}

Restart Caddy and visit the URL mempool.domain.name. You should see your Mempool site initializing and loading.

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Conclusion §

With Caddy handling the reverse proxy, and the appropriate access set up for mempool-api, mempool-web, and mempool-db, your Mempool instance should initialize smoothly, allowing you to securely and privately access all the blockchain informations through your local node, without relying on other services.

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Resources §

• Mempool Github: https://github.com/mempool/mempool