LookUp — Bitcoin Message Scanner

LookUp is a free and open-source .NET server that connects to your local Bitcoin Knots node via RPC, scans blockchain transactions for embedded messages (stored in OP_RETURN scripts), and saves them into a PostgreSQL database.

Check out the official website of the project here!

Build From Source Code

Requirements

• Git
• .NET 8 SDK
• PostgreSQL 15+
• Bitcoin Knots

Setup

1. Clone the repository:

   git clone https://github.com/NotesOnBlockchain/LookUp.Core.git
   cd LookUp
   dotnet build && dotnet run (to generate Config.json)

2. Install EF Core

	dotnet tool install --global dotnet-ef --version 9.*

3. Configure your environment: Update {appdata}/LookUp/Backend/Config.json:

{
  "Network": "Main",
  "BitcoinRpcConnectionString": "CONNECTION:STRING",
  "MainNetBitcoinCoreRpcEndPoint": "http://localhost:8332",
  "TestNetBitcoinCoreRpcEndPoint": "http://localhost:48332",
  "RegTestBitcoinCoreRpcEndPoint": "http://localhost:18443",
  "SQLConnectionString": "Server=[serverName];Host=localhost;Port=5432;Database=[DatabaseName];User ID=[PostgreSQL_Username];Password=[PostgreSQL_Password]"
}

4. Create your Database then apply database migrations:

dotnet ef database update

5. Launch Bitcoin Knots then start the server:

dotnet run

Example OP_RETURN

If a transaction contains:

OP_RETURN 48656c6c6f20576f726c64

The decoded message will be:

"Hello World"