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

Cargo.toml

@@ -27,6 +27,9 @@ rand = "0.3"
 bitcoin_hashes = "0.3"
 bitcoinconsensus = { version = "0.16", optional = true }
 
+[dev-dependencies]
+tempfile = "3"
+
 [dependencies.serde]
 version = "1"
 optional = true

src/consensus/encode.rs

@@ -204,17 +204,29 @@ pub fn serialize_hex<T: ?Sized>(data: &T) -> String
 pub fn deserialize<'a, T>(data: &'a [u8]) -> Result<T, Error>
      where T: Decodable<Cursor<&'a [u8]>>
 {
-    let mut decoder = Cursor::new(data);
+    let (rv, consumed) = deserialize_partial(data)?;
-    let rv = Decodable::consensus_decode(&mut decoder)?;
 
-    // Fail if data is not consumed entirely.
+    // Fail if data are not consumed entirely.
-    if decoder.position() == data.len() as u64 {
+    if consumed == data.len() {
         Ok(rv)
     } else {
         Err(Error::ParseFailed("data not consumed entirely when explicitly deserializing"))
     }
 }
 
+/// Deserialize an object from a vector, but will not report an error if said deserialization
+/// doesn't consume the entire vector.
+pub fn deserialize_partial<'a, T>(data: &'a [u8]) -> Result<(T, usize), Error>
+    where T: Decodable<Cursor<&'a [u8]>>
+{
+    let mut decoder = Cursor::new(data);
+    let rv = Decodable::consensus_decode(&mut decoder)?;
+    let consumed = decoder.position() as usize;
+
+    Ok((rv, consumed))
+}
+
+
 /// A simple Encoder trait
 pub trait Encoder {
     /// Output a 64-bit uint

src/consensus/mod.rs

@@ -21,5 +21,6 @@
 pub mod encode;
 pub mod params;
 
-pub use self::encode::{Encodable, Decodable, Encoder, Decoder, serialize, deserialize};
+pub use self::encode::{Encodable, Decodable, Encoder, Decoder,
+                       serialize, deserialize, deserialize_partial};
 pub use self::params::Params;

src/network/message.rs

@@ -21,7 +21,6 @@
 
 use std::iter;
 use std::io::Cursor;
-use std::sync::mpsc::Sender;
 
 use blockdata::block;
 use blockdata::transaction;
@@ -32,7 +31,6 @@ use network::message_filter;
 use consensus::encode::{Decodable, Encodable};
 use consensus::encode::CheckedData;
 use consensus::encode::{self, serialize, Encoder, Decoder};
-use util;
 
 /// Serializer for command string
 #[derive(PartialEq, Eq, Clone, Debug)]
@@ -63,6 +61,7 @@ impl<D: Decoder> Decodable<D> for CommandString {
     }
 }
 
+#[derive(Debug)]
 /// A Network message
 pub struct RawNetworkMessage {
     /// Magic bytes to identify the network these messages are meant for
@@ -71,14 +70,6 @@ pub struct RawNetworkMessage {
     pub payload: NetworkMessage
 }
 
-/// A response from the peer-connected socket
-pub enum SocketResponse {
-    /// A message was received
-    MessageReceived(NetworkMessage),
-    /// An error occurred and the socket needs to close
-    ConnectionFailed(util::Error, Sender<()>)
-}
-
 #[derive(Clone, PartialEq, Eq, Debug)]
 /// A Network message payload. Proper documentation is available on at
 /// [Bitcoin Wiki: Protocol Specification](https://en.bitcoin.it/wiki/Protocol_specification)
@@ -237,8 +228,7 @@ impl<D: Decoder> Decodable<D> for RawNetworkMessage {
 #[cfg(test)]
 mod test {
     use super::{RawNetworkMessage, NetworkMessage, CommandString};
-
+    use consensus::encode::{deserialize, deserialize_partial, serialize};
-    use consensus::encode::{deserialize, serialize};
 
     #[test]
     fn serialize_commandstring_test() {
@@ -290,4 +280,89 @@ mod test {
                                   0x00, 0x00, 0x00, 0x00, 0x5d, 0xf6, 0xe0, 0xe2]);
     }
 
+    #[test]
+    fn deserialize_getaddr_test() {
+        let msg = deserialize(
+            &[0xf9, 0xbe, 0xb4, 0xd9, 0x67, 0x65, 0x74, 0x61,
+                0x64, 0x64, 0x72, 0x00, 0x00, 0x00, 0x00, 0x00,
+                0x00, 0x00, 0x00, 0x00, 0x5d, 0xf6, 0xe0, 0xe2]);
+        let preimage = RawNetworkMessage { magic: 0xd9b4bef9, payload: NetworkMessage::GetAddr };
+        assert!(msg.is_ok());
+        let msg : RawNetworkMessage = msg.unwrap();
+        assert_eq!(preimage.magic, msg.magic);
+        assert_eq!(preimage.payload, msg.payload);
+    }
+
+    #[test]
+    fn deserialize_version_test() {
+        let msg = deserialize::<RawNetworkMessage>(
+            &[  0xf9, 0xbe, 0xb4, 0xd9, 0x76, 0x65, 0x72, 0x73,
+                0x69, 0x6f, 0x6e, 0x00, 0x00, 0x00, 0x00, 0x00,
+                0x66, 0x00, 0x00, 0x00, 0xbe, 0x61, 0xb8, 0x27,
+                0x7f, 0x11, 0x01, 0x00, 0x0d, 0x04, 0x00, 0x00,
+                0x00, 0x00, 0x00, 0x00, 0xf0, 0x0f, 0x4d, 0x5c,
+                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff,
+                0x5b, 0xf0, 0x8c, 0x80, 0xb4, 0xbd, 0x0d, 0x04,
+                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+                0xfa, 0xa9, 0x95, 0x59, 0xcc, 0x68, 0xa1, 0xc1,
+                0x10, 0x2f, 0x53, 0x61, 0x74, 0x6f, 0x73, 0x68,
+                0x69, 0x3a, 0x30, 0x2e, 0x31, 0x37, 0x2e, 0x31,
+                0x2f, 0x93, 0x8c, 0x08, 0x00, 0x01 ]);
+
+        assert!(msg.is_ok());
+        let msg = msg.unwrap();
+        assert_eq!(msg.magic, 0xd9b4bef9);
+        if let NetworkMessage::Version(version_msg) = msg.payload {
+            assert_eq!(version_msg.version, 70015);
+            assert_eq!(version_msg.services, 1037);
+            assert_eq!(version_msg.timestamp, 1548554224);
+            assert_eq!(version_msg.nonce, 13952548347456104954);
+            assert_eq!(version_msg.user_agent, "/Satoshi:0.17.1/");
+            assert_eq!(version_msg.start_height, 560275);
+            assert_eq!(version_msg.relay, true);
+        } else {
+            panic!("Wrong message type");
+        }
+    }
+
+    #[test]
+    fn deserialize_partial_message_test() {
+        let data = [  0xf9, 0xbe, 0xb4, 0xd9, 0x76, 0x65, 0x72, 0x73,
+            0x69, 0x6f, 0x6e, 0x00, 0x00, 0x00, 0x00, 0x00,
+            0x66, 0x00, 0x00, 0x00, 0xbe, 0x61, 0xb8, 0x27,
+            0x7f, 0x11, 0x01, 0x00, 0x0d, 0x04, 0x00, 0x00,
+            0x00, 0x00, 0x00, 0x00, 0xf0, 0x0f, 0x4d, 0x5c,
+            0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+            0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+            0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff,
+            0x5b, 0xf0, 0x8c, 0x80, 0xb4, 0xbd, 0x0d, 0x04,
+            0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+            0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+            0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+            0xfa, 0xa9, 0x95, 0x59, 0xcc, 0x68, 0xa1, 0xc1,
+            0x10, 0x2f, 0x53, 0x61, 0x74, 0x6f, 0x73, 0x68,
+            0x69, 0x3a, 0x30, 0x2e, 0x31, 0x37, 0x2e, 0x31,
+            0x2f, 0x93, 0x8c, 0x08, 0x00, 0x01, 0, 0 ];
+        let msg = deserialize_partial::<RawNetworkMessage>(&data);
+        assert!(msg.is_ok());
+
+        let (msg, consumed) = msg.unwrap();
+        assert_eq!(consumed, data.to_vec().len() - 2);
+        assert_eq!(msg.magic, 0xd9b4bef9);
+        if let NetworkMessage::Version(version_msg) = msg.payload {
+            assert_eq!(version_msg.version, 70015);
+            assert_eq!(version_msg.services, 1037);
+            assert_eq!(version_msg.timestamp, 1548554224);
+            assert_eq!(version_msg.nonce, 13952548347456104954);
+            assert_eq!(version_msg.user_agent, "/Satoshi:0.17.1/");
+            assert_eq!(version_msg.start_height, 560275);
+            assert_eq!(version_msg.relay, true);
+        } else {
+            panic!("Wrong message type");
+        }
+    }
 }

src/network/mod.rs

@@ -29,6 +29,7 @@ pub mod message;
 pub mod message_blockdata;
 pub mod message_network;
 pub mod message_filter;
+pub mod stream_reader;
 
 /// Network error
 #[derive(Debug)]
@@ -50,14 +51,14 @@ impl fmt::Display for Error {
     }
 }
 
-impl error::Error for Error {
+#[doc(hidden)]
-    fn cause(&self) -> Option<&error::Error> {
+impl From<io::Error> for Error {
-        match *self {
+    fn from(err: io::Error) -> Self {
-            Error::Io(ref e) => Some(e),
+        Error::Io(err)
-            Error::SocketMutexPoisoned | Error::SocketNotConnectedToPeer => None,
     }
 }
 
+impl error::Error for Error {
     fn description(&self) -> &str {
         match *self {
             Error::Io(ref e) => e.description(),
@@ -65,4 +66,11 @@ impl error::Error for Error {
             Error::SocketNotConnectedToPeer => "not connected to peer",
         }
     }
+
+    fn cause(&self) -> Option<&error::Error> {
+        match *self {
+            Error::Io(ref e) => Some(e),
+            Error::SocketMutexPoisoned | Error::SocketNotConnectedToPeer => None,
+        }
+    }
 }

src/network/stream_reader.rs

@@ -0,0 +1,327 @@
+// Rust Bitcoin Library
+// Written in 2014 by
+//     Andrew Poelstra <apoelstra@wpsoftware.net>
+//
+// To the extent possible under law, the author(s) have dedicated all
+// copyright and related and neighboring rights to this software to
+// the public domain worldwide. This software is distributed without
+// any warranty.
+//
+// You should have received a copy of the CC0 Public Domain Dedication
+// along with this software.
+// If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.
+//
+
+//! Stream reader
+//!
+//! This module defines `StreamReader` struct and its implementation which is used
+//! for parsing incoming stream into separate `RawNetworkMessage`s, handling assembling
+//! messages from multiple packets or dealing with partial or multiple messages in the stream
+//! (like can happen with reading from TCP socket)
+//!
+
+use std::fmt;
+use std::io;
+use std::io::Read;
+
+use network::message::RawNetworkMessage;
+use consensus::encode;
+
+/// Struct used to configure stream reader function
+pub struct StreamReader<'a> {
+    /// Stream to read from
+    pub stream: &'a mut Read,
+    /// I/O buffer
+    data: Vec<u8>,
+    /// Buffer containing unparsed message part
+    unparsed: Vec<u8>
+}
+
+impl<'a> fmt::Debug for StreamReader<'a> {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "StreamReader with buffer_size={} and unparsed content {:?}",
+               self.data.capacity(), self.unparsed)
+    }
+}
+
+impl<'a> StreamReader<'a> {
+    /// Constructs new stream reader for a given input stream `stream` with
+    /// optional parameter `buffer_size` determining reading buffer size
+    pub fn new(stream: &mut Read, buffer_size: Option<usize>) -> StreamReader {
+        StreamReader {
+            stream,
+            data: vec![0u8; buffer_size.unwrap_or(64 * 1024)],
+            unparsed: vec![]
+        }
+    }
+
+    /// Reads stream and parses next message from its current input,
+    /// also taking into account previously unparsed partial message (if there was such).
+    ///
+    pub fn next_message(&mut self) -> Result<RawNetworkMessage, encode::Error> {
+        loop {
+            match encode::deserialize_partial::<RawNetworkMessage>(&self.unparsed) {
+                // In this case we just have an incomplete data, so we need to read more
+                Err(encode::Error::Io(ref err)) if err.kind () == io::ErrorKind::UnexpectedEof => {
+                    let count = self.stream.read(&mut self.data)?;
+                    if count > 0 {
+                        self.unparsed.extend(self.data[0..count].iter());
+                    }
+                    else {
+                        return Err(encode::Error::Io(io::Error::from(io::ErrorKind::UnexpectedEof)));
+                    }
+                },
+                Err(err) => return Err(err),
+                // We have successfully read from the buffer
+                Ok((message, index)) => {
+                    self.unparsed.drain(..index);
+                    return Ok(message)
+                },
+            }
+        }
+    }
+}
+
+#[cfg(test)]
+mod test {
+    extern crate tempfile;
+
+    use std::thread;
+    use std::fs::File;
+    use std::time::Duration;
+    use std::io::{Write, Seek, SeekFrom};
+    use std::net::{TcpListener, TcpStream, Shutdown};
+    use std::thread::JoinHandle;
+
+    use super::StreamReader;
+    use network::message::{NetworkMessage, RawNetworkMessage};
+
+    // First, let's define some byte arrays for sample messages - dumps are taken from live
+    // Bitcoin Core node v0.17.1 with Wireshark
+    const MSG_VERSION: [u8; 126] = [
+        0xf9, 0xbe, 0xb4, 0xd9, 0x76, 0x65, 0x72, 0x73,
+        0x69, 0x6f, 0x6e, 0x00, 0x00, 0x00, 0x00, 0x00,
+        0x66, 0x00, 0x00, 0x00, 0xbe, 0x61, 0xb8, 0x27,
+        0x7f, 0x11, 0x01, 0x00, 0x0d, 0x04, 0x00, 0x00,
+        0x00, 0x00, 0x00, 0x00, 0xf0, 0x0f, 0x4d, 0x5c,
+        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff,
+        0x5b, 0xf0, 0x8c, 0x80, 0xb4, 0xbd, 0x0d, 0x04,
+        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+        0xfa, 0xa9, 0x95, 0x59, 0xcc, 0x68, 0xa1, 0xc1,
+        0x10, 0x2f, 0x53, 0x61, 0x74, 0x6f, 0x73, 0x68,
+        0x69, 0x3a, 0x30, 0x2e, 0x31, 0x37, 0x2e, 0x31,
+        0x2f, 0x93, 0x8c, 0x08, 0x00, 0x01
+    ];
+
+    const MSG_VERACK: [u8; 24] = [
+        0xf9, 0xbe, 0xb4, 0xd9, 0x76, 0x65, 0x72, 0x61,
+        0x63, 0x6b, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+        0x00, 0x00, 0x00, 0x00, 0x5d, 0xf6, 0xe0, 0xe2
+    ];
+
+    const MSG_PING: [u8; 32] = [
+        0xf9, 0xbe, 0xb4, 0xd9, 0x70, 0x69, 0x6e, 0x67,
+        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+        0x08, 0x00, 0x00, 0x00, 0x24, 0x67, 0xf1, 0x1d,
+        0x64, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    ];
+
+    const MSG_ALERT: [u8; 192] = [
+        0xf9, 0xbe, 0xb4, 0xd9, 0x61, 0x6c, 0x65, 0x72,
+        0x74, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+        0xa8, 0x00, 0x00, 0x00, 0x1b, 0xf9, 0xaa, 0xea,
+        0x60, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+        0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0xff,
+        0x7f, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0xff,
+        0x7f, 0xfe, 0xff, 0xff, 0x7f, 0x01, 0xff, 0xff,
+        0xff, 0x7f, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff,
+        0xff, 0x7f, 0x00, 0xff, 0xff, 0xff, 0x7f, 0x00,
+        0x2f, 0x55, 0x52, 0x47, 0x45, 0x4e, 0x54, 0x3a,
+        0x20, 0x41, 0x6c, 0x65, 0x72, 0x74, 0x20, 0x6b,
+        0x65, 0x79, 0x20, 0x63, 0x6f, 0x6d, 0x70, 0x72,
+        0x6f, 0x6d, 0x69, 0x73, 0x65, 0x64, 0x2c, 0x20,
+        0x75, 0x70, 0x67, 0x72, 0x61, 0x64, 0x65, 0x20,
+        0x72, 0x65, 0x71, 0x75, 0x69, 0x72, 0x65, 0x64,
+        0x00, 0x46, 0x30, 0x44, 0x02, 0x20, 0x65, 0x3f,
+        0xeb, 0xd6, 0x41, 0x0f, 0x47, 0x0f, 0x6b, 0xae,
+        0x11, 0xca, 0xd1, 0x9c, 0x48, 0x41, 0x3b, 0xec,
+        0xb1, 0xac, 0x2c, 0x17, 0xf9, 0x08, 0xfd, 0x0f,
+        0xd5, 0x3b, 0xdc, 0x3a, 0xbd, 0x52, 0x02, 0x20,
+        0x6d, 0x0e, 0x9c, 0x96, 0xfe, 0x88, 0xd4, 0xa0,
+        0xf0, 0x1e, 0xd9, 0xde, 0xda, 0xe2, 0xb6, 0xf9,
+        0xe0, 0x0d, 0xa9, 0x4c, 0xad, 0x0f, 0xec, 0xaa,
+        0xe6, 0x6e, 0xcf, 0x68, 0x9b, 0xf7, 0x1b, 0x50
+    ];
+
+    // Helper functions that checks parsed versions of the messages from the byte arrays above
+    fn check_version_msg(msg: &RawNetworkMessage) {
+        assert_eq!(msg.magic, 0xd9b4bef9);
+        if let NetworkMessage::Version(ref version_msg) = msg.payload {
+            assert_eq!(version_msg.version, 70015);
+            assert_eq!(version_msg.services, 1037);
+            assert_eq!(version_msg.timestamp, 1548554224);
+            assert_eq!(version_msg.nonce, 13952548347456104954);
+            assert_eq!(version_msg.user_agent, "/Satoshi:0.17.1/");
+            assert_eq!(version_msg.start_height, 560275);
+            assert_eq!(version_msg.relay, true);
+        } else {
+            panic!("Wrong message type: expected VersionMessage");
+        }
+    }
+
+    fn check_alert_msg(msg: &RawNetworkMessage) {
+        assert_eq!(msg.magic, 0xd9b4bef9);
+        if let NetworkMessage::Alert(ref alert) = msg.payload {
+            assert_eq!(alert.clone(), [
+                0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+                0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0xff,
+                0x7f, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0xff,
+                0x7f, 0xfe, 0xff, 0xff, 0x7f, 0x01, 0xff, 0xff,
+                0xff, 0x7f, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff,
+                0xff, 0x7f, 0x00, 0xff, 0xff, 0xff, 0x7f, 0x00,
+                0x2f, 0x55, 0x52, 0x47, 0x45, 0x4e, 0x54, 0x3a,
+                0x20, 0x41, 0x6c, 0x65, 0x72, 0x74, 0x20, 0x6b,
+                0x65, 0x79, 0x20, 0x63, 0x6f, 0x6d, 0x70, 0x72,
+                0x6f, 0x6d, 0x69, 0x73, 0x65, 0x64, 0x2c, 0x20,
+                0x75, 0x70, 0x67, 0x72, 0x61, 0x64, 0x65, 0x20,
+                0x72, 0x65, 0x71, 0x75, 0x69, 0x72, 0x65, 0x64,
+                0x00,
+            ].to_vec());
+        } else {
+            panic!("Wrong message type: expected AlertMessage");
+        }
+    }
+
+    #[test]
+    fn parse_multipartmsg_test() {
+        let mut tmpfile: File = tempfile::tempfile().unwrap();
+        let mut reader = StreamReader::new(&mut tmpfile, None);
+        reader.unparsed = MSG_ALERT[..24].to_vec();
+        assert!(reader.next_message().is_err());
+        assert_eq!(reader.unparsed.len(), 24);
+
+        reader.unparsed = MSG_ALERT.to_vec();
+        let message = reader.next_message().unwrap();
+        assert_eq!(reader.unparsed.len(), 0);
+
+        check_alert_msg(&message);
+    }
+
+    fn init_stream(buf: &[u8]) -> File {
+        let mut tmpfile: File = tempfile::tempfile().unwrap();
+        write_file(&mut tmpfile, &buf);
+        tmpfile
+    }
+
+    fn write_file(tmpfile: &mut File, buf: &[u8]) {
+        tmpfile.seek(SeekFrom::End(0)).unwrap();
+        tmpfile.write(&buf).unwrap();
+        tmpfile.flush().unwrap();
+        tmpfile.seek(SeekFrom::Start(0)).unwrap();
+    }
+
+    #[test]
+    fn read_singlemsg_test() {
+        let mut stream = init_stream(&MSG_VERSION);
+        let message = StreamReader::new(&mut stream, None).next_message().unwrap();
+
+        check_version_msg(&message);
+    }
+
+    #[test]
+    fn read_doublemsgs_test() {
+        let mut stream = init_stream(&MSG_VERSION);
+        write_file(&mut stream, &MSG_PING);
+
+        let mut reader = StreamReader::new(&mut stream, None);
+        let message = reader.next_message().unwrap();
+        check_version_msg(&message);
+
+        let msg = reader.next_message().unwrap();
+        assert_eq!(msg.magic, 0xd9b4bef9);
+        if let NetworkMessage::Ping(nonce) = msg.payload {
+            assert_eq!(nonce, 100);
+        } else {
+            panic!("Wrong message type, expected PingMessage");
+        }
+    }
+
+    // Helper function that set ups emulation of client-server TCP connection for
+    // testing message transfer via TCP packets
+    fn serve_tcp(pieces: Vec<Vec<u8>>) -> (JoinHandle<()>, TcpStream) {
+        // 1. Creating server part (emulating Bitcoin Core node)
+        let listener = TcpListener::bind(format!("127.0.0.1:{}", 0)).unwrap();
+        let port = listener.local_addr().unwrap().port();
+        // 2. Spawning thread that will be writing our messages to the TCP Stream at the server side
+        // in async mode
+        let handle = thread::spawn(move || {
+            for ostream in listener.incoming() {
+                let mut ostream = ostream.unwrap();
+
+                for piece in pieces {
+                    ostream.write(&piece[..]).unwrap();
+                    ostream.flush().unwrap();
+                    thread::sleep(Duration::from_secs(1));
+                }
+
+                ostream.shutdown(Shutdown::Both).unwrap();
+                break;
+            }
+        });
+
+        // 3. Creating client side of the TCP socket connection
+        thread::sleep(Duration::from_secs(1));
+        let istream = TcpStream::connect(format!("127.0.0.1:{}", port)).unwrap();
+
+        return (handle, istream)
+    }
+
+    #[test]
+    fn read_multipartmsg_test() {
+        // Setting up TCP connection emulation
+        let (handle, mut istream) = serve_tcp(vec![
+            // single message split in two parts to emulate real network conditions
+            MSG_VERSION[..24].to_vec(), MSG_VERSION[24..].to_vec()
+        ]);
+        let mut reader = StreamReader::new(&mut istream, None);
+
+        // Reading and checking the whole message back
+        let message = reader.next_message().unwrap();
+        check_version_msg(&message);
+
+        // Waiting TCP server thread to terminate
+        handle.join().unwrap();
+    }
+
+    #[test]
+    fn read_sequencemsg_test() {
+        // Setting up TCP connection emulation
+        let (handle, mut istream) = serve_tcp(vec![
+            // Real-world Bitcoin core communication case for /Satoshi:0.17.1/
+            MSG_VERSION[..23].to_vec(), MSG_VERSION[23..].to_vec(),
+            MSG_VERACK.to_vec(),
+            MSG_ALERT[..24].to_vec(), MSG_ALERT[24..].to_vec()
+        ]);
+        let mut reader = StreamReader::new(&mut istream, None);
+
+        // Reading and checking the first message (Version)
+        let message = reader.next_message().unwrap();
+        check_version_msg(&message);
+
+        // Reading and checking the second message (Verack)
+        let msg = reader.next_message().unwrap();
+        assert_eq!(msg.magic, 0xd9b4bef9);
+        assert_eq!(msg.payload, NetworkMessage::Verack, "Wrong message type, expected VerackMessage");
+
+        // Reading and checking the third message (Alert)
+        let msg = reader.next_message().unwrap();
+        check_alert_msg(&msg);
+
+        // Waiting TCP server thread to terminate
+        handle.join().unwrap();
+    }
+}