demo-coins: Hello world Bitcoin Payment API

References

1. Bitcoin Developer Guide at https://developer.bitcoin.org/.

Software and Tools

1. Bitcoin Core 0.21.0. Download from https://bitcoin.org/en/download.
2. Bitcoin RPC Client, https://github.com/Polve/bitcoin-rpc-client.
3. JDK 11. The language level is set to Java 8 features.
4. IntelliJ IDEA.

Local Development

Bitcoin Core

Bitcoin node must run in regtest mode.

Copy the bitcoin.conf file available under repository's bitcoin-files folder to the local .bitcoin folder. Backup the existing conf file if Bitcoin Core is already installed on development machine.

Start the bitcoin daemon.

bitcoind -regtest -daemon

Create wallets for test-funds, receiver and sender.

bitcoin-cli -regtest createwallet "test-funds"
bitcoin-cli -regtest createwallet "receiver"
bitcoin-cli -regtest createwallet "sender"

View the loaded wallets.

bitcoin-cli -regtest listwallets

The wallets have to be created the first time or after deleting the .bitcoin/regtest folder. Other times they can be loaded as shown below, if not loaded already.

bitcoin-cli -regtest loadwallet "test-funds"
bitcoin-cli -regtest loadwallet "receiver"
bitcoin-cli -regtest loadwallet "sender"

Generate bitcoins to the test-funds wallet.

NEW_ADDRESS=$(bitcoin-cli -regtest -rpcwallet=test-funds getnewaddress)
bitcoin-cli -regtest generatetoaddress 1001 $NEW_ADDRESS
unset NEW_ADDRESS

Transfer bitcoins from test-funds to receiver wallet.

NEW_ADDRESS=$(bitcoin-cli -regtest -rpcwallet=receiver getnewaddress)
bitcoin-cli -regtest -rpcwallet=test-funds sendtoaddress $NEW_ADDRESS 3000.00
bitcoin-cli -regtest generatetoaddress 1 $NEW_ADDRESS
unset NEW_ADDRESS

Similarly, transfer bitcoins from test-funds to sender wallet.

NEW_ADDRESS=$(bitcoin-cli -regtest -rpcwallet=sender getnewaddress)
bitcoin-cli -regtest -rpcwallet=test-funds sendtoaddress $NEW_ADDRESS 3000.00
bitcoin-cli -regtest generatetoaddress 1 $NEW_ADDRESS
unset NEW_ADDRESS

Spring Boot Application

To build artifact for local development.

./mvnw clean package

Deploy as,

java -jar target/demo-coins-0.0.1-SNAPSHOT.jar

The application APIs will be available at http://localhost:8080/coins/swagger-ui/index.html.

The H2 database console will be available at http://localhost:8080/coins/h2-console. The connection settings can be taken from application.properties.