Better RawNewtorkMessage deserealization from IO stream (#231)
Follow-up to https://github.com/rust-bitcoin/rust-bitcoin/pull/229
While working with remote peers over the network it is required to deserealize RawNetworkMessage from `TCPStream` to read the incoming messages. These messages can be partial – or one TCP packet can contain few of them. To make the library usable for such use cases, I have implemented the required functionality and covered it with unit tests.
Sample usage:
```rust
fn run() -> Result<(), Error> {
// Opening stream to the remote bitcoind peer
let mut stream = TcpStream::connect(SocketAddr::from(([37, 187, 0, 47], 8333));
let start = SystemTime::now();
// Constructing and sending `version` message to get some messages back from the remote peer
let since_the_epoch = start.duration_since(UNIX_EPOCH)
.expect("Time went backwards");
let version_msg = message::RawNetworkMessage {
magic: constants::Network::Bitcoin.magic(),
payload: message::NetworkMessage::Version(message_network::VersionMessage::new(
0,
since_the_epoch.as_secs() as i64,
address::Address::new(receiver, 0),
address::Address::new(receiver, 0),
0,
String::from("macx0r"),
0
))
};
stream.write(encode::serialize(&version_msg).as_slice())?;
// Receiving incoming messages
let mut buffer = vec![];
loop {
let result = StreamReader::new(&mut stream, None).read_messages();
if let Err(err) = result {
stream.shutdown(Shutdown::Both)?;
return Err(Error::DataError(err))
}
for msg in result.unwrap() {
println!("Received message: {:?}", msg.payload);
}
}
}
```
Sample output is the following:
```
Received message: Version(VersionMessage { version: 70015, services: 1037, timestamp: 1548637162, receiver: Address {services: 0, address: [0, 0, 0, 0, 0, 65535, 23536, 35968], port: 33716}, sender: Address {services: 1037, address: [0, 0, 0, 0, 0, 0, 0, 0], port: 0}, nonce: 1370726880972892633, user_agent: "/Satoshi:0.17.99/", start_height: 560412, relay: true })
Received message: Verack
Received message: Alert([1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 255, 255, 255, 127, 0, 0, 0, 0, 255, 255, 255, 127, 254, 255, 255, 127, 1, 255, 255, 255, 127, 0, 0, 0, 0, 255, 255, 255, 127, 0, 255, 255, 255, 127, 0, 47, 85, 82, 71, 69, 78, 84, 58, 32, 65, 108, 101, 114, 116, 32, 107, 101, 121, 32, 99, 111, 109, 112, 114, 111, 109, 105, 115, 101, 100, 44, 32, 117, 112, 103, 114, 97, 100, 101, 32, 114, 101, 113, 117, 105, 114, 101, 100, 0])
```
Working sample code can be found here: https://github.com/dr-orlovsky/bitcoinbigdata-netlistener