BITCOIN

Bitcoin RPC Explorer (Go)

A lightweight Bitcoin blockchain explorer built in Go using Bitcoin Core JSON-RPC. This project was developed in a step-by-step bootcamp style, progressively building from basic RPC calls to a full blockchain inspection tool.

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Overview

This project connects to a Bitcoin Core regtest node and allows you to:

• Query wallet balances
• List wallet transactions
• Decode raw transactions
• Inspect blocks
• Fetch blockchain metadata
• Interact with multiple wallets (alice, bob, etc.)

It acts as a minimal blockchain explorer backend.

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Features

1. Wallet Balance

Fetch balances for specific wallets:

• getbalance

2. Transaction Listing

View wallet transaction history:

• listtransactions

Includes:

• Category (receive/send/mining)
• Amount
• Transaction ID
• Confirmations

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3. Transaction Decoder

Decode raw transactions:

• getrawtransaction

Shows:

• VIN (inputs)
• VOUT (outputs)
• CoinBase detection (mining rewards)
• Address extraction

Handles both:

• addresses[]
• fallback address

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4. Blockchain Info

Fetch network status:

• getblockchaininfo

Displays:

• Chain type (regtest/testnet/mainnet)
• Block height
• Difficulty

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5. Block Explorer

Inspect blocks using:

• getblockhash
• getblock

Features:

• Auto-fetch best block if no hash provided
• Block height
• Timestamp
• Transaction count
• Transaction list

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Architecture

Go Application
   ↓
RPC Client (HTTP + JSON)
   ↓
Bitcoin Core (regtest)
   ↓
Blockchain Data

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RPC Helper Function

All blockchain interactions go through a reusable RPC wrapper:

• Handles authentication (rpcuser / rpcpassword)
• Supports wallet-specific routing
• Decodes JSON responses into Go structs

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Example Workflow

1. Start Bitcoin Core in regtest:

bitcoind -regtest -daemon

2. Create/load wallets:

bitcoin-cli -regtest createwallet "alice"
bitcoin-cli -regtest createwallet "bob"

3. Run the Go app:

go run .

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Sample Output

=== Wallet: alice ===
Balance: 89.9999859 BTC

=== Transactions for alice ===
IN  +50.00000000 BTC | 9 confs
        TXID: dbe6ff95...
OUT -10.00000000 BTC | 1 confs
        TXID: a4171cb8...

=== BLOCK INFO ===
Height: 102
Hash: 000000...
Time: 1710000000
Tx count: 1

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Key Concepts Learned

Bitcoin RPC

• JSON-RPC communication with Bitcoin Core
• Methods like getblock, getbalance, listtransactions

Wallet Management

• Loading wallets into memory
• Using /wallet/<name> RPC routing

Blockchain Data Structures

• VIN / VOUT model (UTXO system)
• ScriptPubKey decoding
• Coinbase transactions

Go Concepts

• Struct mapping to JSON
• Error handling patterns
• Reusable RPC client design

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Common Issues Solved

• Wallet not loaded errors → solved via loadwallet
• Multiple wallet selection → solved via /wallet/<name>
• JSON mismatches (address vs addresses[])
• Regtest configuration issues
• RPC authentication setup

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Requirements

• Go 1.18+
• Bitcoin Core (regtest mode enabled)
• RPC enabled in bitcoin.conf

Example config:

server=1
regtest=1
rpcuser=place_username_here
rpcpassword=place_password_here

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Future Improvements

• REST API wrapper
• Mempool explorer
• UTXO tracker
• Frontend dashboard
• Real-time block updates (WebSockets)
• Transaction graph visualization

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Author

Built as part of a Bitcoin RPC bootcamp project — evolving from basic RPC calls to a full blockchain inspection tool in Go.