rpc.rs 8.95 KB
Newer Older
Roman Zeyde's avatar
Roman Zeyde committed
1 2
use bitcoin::blockdata::block::BlockHeader;
use bitcoin::network::serialize::serialize;
3
use bitcoin::util::hash::Sha256dHash;
4
use itertools;
Roman Zeyde's avatar
WiP  
Roman Zeyde committed
5
use serde_json::{from_str, Number, Value};
Roman Zeyde's avatar
Roman Zeyde committed
6
use std::collections::HashMap;
7
use std::io::{BufRead, BufReader, Write};
Roman Zeyde's avatar
WiP  
Roman Zeyde committed
8 9
use std::net::{SocketAddr, TcpListener, TcpStream};

Roman Zeyde's avatar
Roman Zeyde committed
10 11
use query::{Query, Status};
use index::FullHash;
12
use util;
Roman Zeyde's avatar
Roman Zeyde committed
13 14
use crypto::digest::Digest;
use crypto::sha2::Sha256;
Roman Zeyde's avatar
WiP  
Roman Zeyde committed
15 16 17

error_chain!{}

18
struct Handler<'a> {
19
    query: &'a Query<'a>,
Roman Zeyde's avatar
WiP  
Roman Zeyde committed
20 21
}

Roman Zeyde's avatar
Roman Zeyde committed
22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59
// TODO: Sha256dHash should be a generic hash-container (since script hash is single SHA256)
fn hash_from_params(params: &[Value]) -> Result<Sha256dHash> {
    let script_hash = params.get(0).chain_err(|| "missing hash")?;
    let script_hash = script_hash.as_str().chain_err(|| "non-string hash")?;
    let script_hash = Sha256dHash::from_hex(script_hash).chain_err(|| "non-hex hash")?;
    Ok(script_hash)
}

fn history_from_status(status: &Status) -> Vec<(u32, Sha256dHash)> {
    let mut txns_map = HashMap::<Sha256dHash, u32>::new();
    for f in &status.funding {
        txns_map.insert(f.txn_id, f.height);
    }
    for s in &status.spending {
        txns_map.insert(s.txn_id, s.height);
    }
    let mut txns: Vec<(u32, Sha256dHash)> =
        txns_map.into_iter().map(|item| (item.1, item.0)).collect();
    txns.sort();
    txns
}

fn hash_from_status(status: &Status) -> Option<FullHash> {
    let txns = history_from_status(status);
    if txns.is_empty() {
        return None;
    }

    let mut hash = FullHash::default();
    let mut sha2 = Sha256::new();
    for (height, txn_id) in txns {
        let part = format!("{}:{}:", txn_id.be_hex_string(), height);
        sha2.input(part.as_bytes());
    }
    sha2.result(&mut hash);
    Some(hash)
}

Roman Zeyde's avatar
Roman Zeyde committed
60 61 62 63 64 65 66 67 68 69 70 71
fn format_header(header: &BlockHeader, height: usize) -> Value {
    json!({
        "block_height": height,
        "version": header.version,
        "prev_block_hash": header.prev_blockhash.be_hex_string(),
        "merkle_root": header.merkle_root.be_hex_string(),
        "timestamp": header.time,
        "bits": header.bits,
        "nonce": header.nonce
    })
}

72 73
impl<'a> Handler<'a> {
    fn blockchain_headers_subscribe(&self) -> Result<Value> {
Roman Zeyde's avatar
Roman Zeyde committed
74 75 76
        let entry = self.query
            .get_best_header()
            .chain_err(|| "no headers found")?;
Roman Zeyde's avatar
Roman Zeyde committed
77
        Ok(format_header(entry.header(), entry.height()))
78
    }
Roman Zeyde's avatar
WiP  
Roman Zeyde committed
79

80 81 82
    fn server_version(&self) -> Result<Value> {
        Ok(json!(["LES 0.1.0", "1.2"]))
    }
Roman Zeyde's avatar
WiP  
Roman Zeyde committed
83

84 85 86
    fn server_banner(&self) -> Result<Value> {
        Ok(json!("Welcome to Local Electrum Server!\n"))
    }
Roman Zeyde's avatar
WiP  
Roman Zeyde committed
87

88 89 90
    fn server_donation_address(&self) -> Result<Value> {
        Ok(json!("No, thanks :)\n"))
    }
Roman Zeyde's avatar
WiP  
Roman Zeyde committed
91

92 93 94
    fn server_peers_subscribe(&self) -> Result<Value> {
        Ok(json!([]))
    }
Roman Zeyde's avatar
WiP  
Roman Zeyde committed
95

96 97 98
    fn mempool_get_fee_histogram(&self) -> Result<Value> {
        Ok(json!([])) // TODO: consult with actual mempool
    }
Roman Zeyde's avatar
WiP  
Roman Zeyde committed
99

100 101 102 103 104 105
    fn blockchain_block_get_chunk(&self, params: &[Value]) -> Result<Value> {
        const CHUNK_SIZE: usize = 2016;
        let index = params.get(0).chain_err(|| "missing index")?;
        let index = index.as_u64().chain_err(|| "non-number index")? as usize;
        let heights: Vec<usize> = (0..CHUNK_SIZE).map(|h| index * CHUNK_SIZE + h).collect();
        let headers = self.query.get_headers(&heights);
Roman Zeyde's avatar
Roman Zeyde committed
106 107 108 109 110 111
        let result = itertools::join(
            headers
                .into_iter()
                .map(|x| util::hexlify(&serialize(&x).unwrap())),
            "",
        );
112 113 114
        Ok(json!(result))
    }

Roman Zeyde's avatar
Roman Zeyde committed
115 116 117 118 119 120 121
    fn blockchain_block_get_header(&self, params: &[Value]) -> Result<Value> {
        let height = params.get(0).chain_err(|| "missing height")?;
        let height = height.as_u64().chain_err(|| "non-number height")? as usize;
        let headers = self.query.get_headers(&vec![height]);
        Ok(json!(format_header(&headers[0], height)))
    }

122
    fn blockchain_estimatefee(&self, _params: &[Value]) -> Result<Value> {
123 124
        Ok(json!(1e-5)) // TODO: consult with actual mempool
    }
Roman Zeyde's avatar
WiP  
Roman Zeyde committed
125

Roman Zeyde's avatar
Roman Zeyde committed
126 127 128 129 130 131 132 133 134 135 136 137
    fn blockchain_relayfee(&self) -> Result<Value> {
        Ok(json!(1e-5)) // TODO: consult with actual node
    }

    fn blockchain_scripthash_subscribe(&self, params: &[Value]) -> Result<Value> {
        let script_hash = hash_from_params(&params).chain_err(|| "bad script_hash")?;
        let status = self.query.status(&script_hash[..]);

        Ok(match hash_from_status(&status) {
            Some(hash) => Value::String(util::hexlify(&hash)),
            None => Value::Null,
        })
138
    }
Roman Zeyde's avatar
WiP  
Roman Zeyde committed
139

140
    fn blockchain_scripthash_get_balance(&self, params: &[Value]) -> Result<Value> {
Roman Zeyde's avatar
Roman Zeyde committed
141 142 143
        let script_hash = hash_from_params(&params).chain_err(|| "bad script_hash")?;
        let status = self.query.status(&script_hash[..]);
        Ok(json!({ "confirmed": status.balance })) // TODO: "unconfirmed"
144
    }
Roman Zeyde's avatar
WiP  
Roman Zeyde committed
145

Roman Zeyde's avatar
Roman Zeyde committed
146 147 148 149 150 151 152 153 154
    fn blockchain_scripthash_get_history(&self, params: &[Value]) -> Result<Value> {
        let script_hash = hash_from_params(&params).chain_err(|| "bad script_hash")?;
        let status = self.query.status(&script_hash[..]);
        Ok(json!(Value::Array(
            history_from_status(&status)
                .into_iter()
                .map(|item| json!({"height": item.0, "tx_hash": item.1.be_hex_string()}))
                .collect()
        )))
155
    }
Roman Zeyde's avatar
WiP  
Roman Zeyde committed
156

157
    fn blockchain_transaction_get(&self, params: &[Value]) -> Result<Value> {
Roman Zeyde's avatar
Roman Zeyde committed
158
        // TODO: handle 'verbose' param
Roman Zeyde's avatar
Roman Zeyde committed
159
        let tx_hash = hash_from_params(params).chain_err(|| "bad tx_hash")?;
160
        let tx_hex = util::hexlify(&self.query.get_tx(&tx_hash));
161
        Ok(json!(tx_hex))
Roman Zeyde's avatar
WiP  
Roman Zeyde committed
162 163
    }

164
    fn blockchain_transaction_get_merkle(&self, _params: &[Value]) -> Result<Value> {
165 166
        Ok(json!({"block_height": 123, "merkle": ["A", "B", "C"], "pos": 45}))
    }
Roman Zeyde's avatar
WiP  
Roman Zeyde committed
167

168
    fn handle_command(&self, method: &str, params: &[Value], id: &Number) -> Result<Value> {
169 170 171 172 173 174 175
        let result = match method {
            "blockchain.headers.subscribe" => self.blockchain_headers_subscribe(),
            "server.version" => self.server_version(),
            "server.banner" => self.server_banner(),
            "server.donation_address" => self.server_donation_address(),
            "server.peers.subscribe" => self.server_peers_subscribe(),
            "mempool.get_fee_histogram" => self.mempool_get_fee_histogram(),
176
            "blockchain.block.get_chunk" => self.blockchain_block_get_chunk(&params),
Roman Zeyde's avatar
Roman Zeyde committed
177
            "blockchain.block.get_header" => self.blockchain_block_get_header(&params),
178
            "blockchain.estimatefee" => self.blockchain_estimatefee(&params),
Roman Zeyde's avatar
Roman Zeyde committed
179
            "blockchain.relayfee" => self.blockchain_relayfee(),
180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217
            "blockchain.scripthash.subscribe" => self.blockchain_scripthash_subscribe(&params),
            "blockchain.scripthash.get_balance" => self.blockchain_scripthash_get_balance(&params),
            "blockchain.scripthash.get_history" => self.blockchain_scripthash_get_history(&params),
            "blockchain.transaction.get" => self.blockchain_transaction_get(&params),
            "blockchain.transaction.get_merkle" => self.blockchain_transaction_get_merkle(&params),
            &_ => bail!("unknown method {} {:?}", method, params),
        }?;
        let reply = json!({"jsonrpc": "2.0", "id": id, "result": result});
        Ok(reply)
    }

    pub fn run(self, mut stream: TcpStream, addr: SocketAddr) -> Result<()> {
        let mut reader = BufReader::new(stream
            .try_clone()
            .chain_err(|| "failed to clone TcpStream")?);
        let mut line = String::new();

        loop {
            line.clear();
            reader
                .read_line(&mut line)
                .chain_err(|| "failed to read a request")?;
            if line.is_empty() {
                break;
            }
            let line = line.trim_right();
            let cmd: Value = from_str(line).chain_err(|| "invalid JSON format")?;

            let reply = match (cmd.get("method"), cmd.get("params"), cmd.get("id")) {
                (
                    Some(&Value::String(ref method)),
                    Some(&Value::Array(ref params)),
                    Some(&Value::Number(ref id)),
                ) => self.handle_command(method, params, id)?,
                _ => bail!("invalid command: {}", cmd),
            };

            debug!("[{}] {} -> {}", addr, cmd, reply);
Roman Zeyde's avatar
Roman Zeyde committed
218
            let line = reply.to_string() + "\n";
219 220 221
            stream
                .write_all(line.as_bytes())
                .chain_err(|| "failed to send response")?;
Roman Zeyde's avatar
WiP  
Roman Zeyde committed
222
        }
223
        Ok(())
Roman Zeyde's avatar
WiP  
Roman Zeyde committed
224 225 226
    }
}

227
pub fn serve(addr: &str, query: &Query) {
228 229
    let listener = TcpListener::bind(addr).unwrap();
    info!("RPC server running on {}", addr);
Roman Zeyde's avatar
WiP  
Roman Zeyde committed
230 231 232
    loop {
        let (stream, addr) = listener.accept().unwrap();
        info!("[{}] connected peer", addr);
233 234
        let handler = Handler { query };
        match handler.run(stream, addr) {
Roman Zeyde's avatar
WiP  
Roman Zeyde committed
235 236 237 238 239 240 241 242 243 244
            Ok(()) => info!("[{}] disconnected peer", addr),
            Err(ref e) => {
                error!("[{}] {}", addr, e);
                for e in e.iter().skip(1) {
                    error!("caused by: {}", e);
                }
            }
        }
    }
}