2019-03-21 00:02:52 +00:00
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use super::methods::*;
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2019-11-27 01:47:46 +00:00
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use crate::rpc::{
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codec::{
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base::{BaseInboundCodec, BaseOutboundCodec},
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ssz::{SSZInboundCodec, SSZOutboundCodec},
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InboundCodec, OutboundCodec,
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},
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methods::ResponseTermination,
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2019-07-15 08:41:05 +00:00
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};
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use futures::{
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future::{self, FutureResult},
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sink, stream, Sink, Stream,
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2019-07-15 07:07:23 +00:00
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};
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2019-08-10 01:44:17 +00:00
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use libp2p::core::{upgrade, InboundUpgrade, OutboundUpgrade, ProtocolName, UpgradeInfo};
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2019-03-14 14:50:59 +00:00
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use std::io;
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2019-07-09 05:44:23 +00:00
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use std::time::Duration;
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2019-07-15 07:07:23 +00:00
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use tokio::codec::Framed;
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2019-03-14 14:50:59 +00:00
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use tokio::io::{AsyncRead, AsyncWrite};
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2019-07-15 07:07:23 +00:00
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use tokio::prelude::*;
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2019-07-15 08:41:05 +00:00
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use tokio::timer::timeout;
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2019-07-09 05:44:23 +00:00
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use tokio::util::FutureExt;
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2019-08-29 11:23:28 +00:00
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use tokio_io_timeout::TimeoutStream;
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2019-03-14 14:50:59 +00:00
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/// The maximum bytes that can be sent across the RPC.
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2019-07-05 08:59:53 +00:00
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const MAX_RPC_SIZE: usize = 4_194_304; // 4M
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/// The protocol prefix the RPC protocol id.
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2019-08-29 11:23:28 +00:00
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const PROTOCOL_PREFIX: &str = "/eth2/beacon_chain/req";
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/// Time allowed for the first byte of a request to arrive before we time out (Time To First Byte).
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const TTFB_TIMEOUT: u64 = 5;
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/// The number of seconds to wait for the first bytes of a request once a protocol has been
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/// established before the stream is terminated.
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const REQUEST_TIMEOUT: u64 = 15;
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2019-03-14 14:50:59 +00:00
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#[derive(Debug, Clone)]
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pub struct RPCProtocol;
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impl UpgradeInfo for RPCProtocol {
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2019-08-10 01:44:17 +00:00
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type Info = ProtocolId;
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2019-07-05 08:59:53 +00:00
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type InfoIter = Vec<Self::Info>;
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2019-03-14 14:50:59 +00:00
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fn protocol_info(&self) -> Self::InfoIter {
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2019-07-05 08:59:53 +00:00
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vec![
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2019-11-27 01:47:46 +00:00
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ProtocolId::new("status", "1", "ssz"),
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2019-08-29 11:23:28 +00:00
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ProtocolId::new("goodbye", "1", "ssz"),
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2019-11-27 01:47:46 +00:00
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ProtocolId::new("blocks_by_range", "1", "ssz"),
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ProtocolId::new("blocks_by_root", "1", "ssz"),
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2019-07-05 08:59:53 +00:00
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]
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2019-03-14 14:50:59 +00:00
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}
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}
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2019-07-05 08:59:53 +00:00
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/// Tracks the types in a protocol id.
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2019-08-10 01:44:17 +00:00
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#[derive(Clone)]
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2019-07-05 08:59:53 +00:00
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pub struct ProtocolId {
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/// The rpc message type/name.
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pub message_name: String,
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2019-07-04 04:05:01 +00:00
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2019-07-05 08:59:53 +00:00
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/// The version of the RPC.
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2019-07-11 05:11:31 +00:00
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pub version: String,
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2019-07-04 04:05:01 +00:00
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2019-07-05 08:59:53 +00:00
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/// The encoding of the RPC.
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pub encoding: String,
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2019-08-10 01:44:17 +00:00
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/// The protocol id that is formed from the above fields.
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protocol_id: String,
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2019-07-05 08:59:53 +00:00
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}
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2019-07-04 04:05:01 +00:00
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2019-07-05 08:59:53 +00:00
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/// An RPC protocol ID.
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impl ProtocolId {
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2019-07-11 05:11:31 +00:00
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pub fn new(message_name: &str, version: &str, encoding: &str) -> Self {
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2019-08-10 01:44:17 +00:00
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let protocol_id = format!(
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"{}/{}/{}/{}",
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PROTOCOL_PREFIX, message_name, version, encoding
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);
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2019-07-05 08:59:53 +00:00
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ProtocolId {
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2019-07-09 05:44:23 +00:00
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message_name: message_name.into(),
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2019-07-11 05:11:31 +00:00
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version: version.into(),
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2019-07-09 05:44:23 +00:00
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encoding: encoding.into(),
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2019-08-10 01:44:17 +00:00
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protocol_id,
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2019-07-05 08:59:53 +00:00
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}
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}
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}
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2019-04-03 05:23:09 +00:00
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2019-08-10 01:44:17 +00:00
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impl ProtocolName for ProtocolId {
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fn protocol_name(&self) -> &[u8] {
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self.protocol_id.as_bytes()
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2019-07-05 08:59:53 +00:00
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}
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}
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2019-03-14 14:50:59 +00:00
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2019-07-09 05:44:23 +00:00
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/* Inbound upgrade */
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// The inbound protocol reads the request, decodes it and returns the stream to the protocol
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// handler to respond to once ready.
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2019-07-16 12:32:37 +00:00
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pub type InboundOutput<TSocket> = (RPCRequest, InboundFramed<TSocket>);
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2019-08-29 11:23:28 +00:00
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pub type InboundFramed<TSocket> = Framed<TimeoutStream<upgrade::Negotiated<TSocket>>, InboundCodec>;
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2019-07-16 12:32:37 +00:00
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type FnAndThen<TSocket> = fn(
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(Option<RPCRequest>, InboundFramed<TSocket>),
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) -> FutureResult<InboundOutput<TSocket>, RPCError>;
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2019-07-15 08:41:05 +00:00
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type FnMapErr<TSocket> = fn(timeout::Error<(RPCError, InboundFramed<TSocket>)>) -> RPCError;
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2019-07-09 05:44:23 +00:00
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impl<TSocket> InboundUpgrade<TSocket> for RPCProtocol
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where
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TSocket: AsyncRead + AsyncWrite,
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{
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2019-07-16 12:32:37 +00:00
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type Output = InboundOutput<TSocket>;
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2019-07-09 05:44:23 +00:00
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type Error = RPCError;
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2019-07-15 07:07:23 +00:00
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2019-07-15 08:41:05 +00:00
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type Future = future::AndThen<
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future::MapErr<
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timeout::Timeout<stream::StreamFuture<InboundFramed<TSocket>>>,
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FnMapErr<TSocket>,
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2019-07-09 05:44:23 +00:00
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>,
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2019-07-16 12:32:37 +00:00
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FutureResult<InboundOutput<TSocket>, RPCError>,
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2019-07-15 08:41:05 +00:00
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FnAndThen<TSocket>,
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2019-07-09 05:44:23 +00:00
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>;
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fn upgrade_inbound(
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self,
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socket: upgrade::Negotiated<TSocket>,
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2019-08-10 01:44:17 +00:00
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protocol: ProtocolId,
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2019-07-09 05:44:23 +00:00
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) -> Self::Future {
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2019-08-10 01:44:17 +00:00
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match protocol.encoding.as_str() {
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2019-07-15 07:07:23 +00:00
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"ssz" | _ => {
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2019-08-10 01:44:17 +00:00
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let ssz_codec = BaseInboundCodec::new(SSZInboundCodec::new(protocol, MAX_RPC_SIZE));
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2019-07-15 08:41:05 +00:00
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let codec = InboundCodec::SSZ(ssz_codec);
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2019-08-29 11:23:28 +00:00
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let mut timed_socket = TimeoutStream::new(socket);
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timed_socket.set_read_timeout(Some(Duration::from_secs(TTFB_TIMEOUT)));
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Framed::new(timed_socket, codec)
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2019-07-15 08:41:05 +00:00
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.into_future()
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2019-07-16 12:32:37 +00:00
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.timeout(Duration::from_secs(REQUEST_TIMEOUT))
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2019-07-15 08:41:05 +00:00
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.map_err(RPCError::from as FnMapErr<TSocket>)
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.and_then({
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2019-07-16 12:32:37 +00:00
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|(req, stream)| match req {
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Some(req) => futures::future::ok((req, stream)),
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None => futures::future::err(RPCError::Custom(
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"Stream terminated early".into(),
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)),
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2019-07-15 08:41:05 +00:00
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}
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} as FnAndThen<TSocket>)
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2019-07-15 07:07:23 +00:00
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}
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}
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2019-07-09 05:44:23 +00:00
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}
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}
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/* Outbound request */
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// Combines all the RPC requests into a single enum to implement `UpgradeInfo` and
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// `OutboundUpgrade`
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2019-11-27 01:47:46 +00:00
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#[derive(Debug, Clone, PartialEq)]
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2019-07-05 08:59:53 +00:00
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pub enum RPCRequest {
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2019-11-27 01:47:46 +00:00
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Status(StatusMessage),
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2019-07-16 12:32:37 +00:00
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Goodbye(GoodbyeReason),
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2019-11-27 01:47:46 +00:00
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BlocksByRange(BlocksByRangeRequest),
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BlocksByRoot(BlocksByRootRequest),
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2019-07-05 08:59:53 +00:00
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}
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2019-03-14 14:50:59 +00:00
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2019-07-05 08:59:53 +00:00
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impl UpgradeInfo for RPCRequest {
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2019-08-10 01:44:17 +00:00
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type Info = ProtocolId;
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2019-07-05 08:59:53 +00:00
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type InfoIter = Vec<Self::Info>;
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2019-07-04 04:05:01 +00:00
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2019-07-05 08:59:53 +00:00
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// add further protocols as we support more encodings/versions
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fn protocol_info(&self) -> Self::InfoIter {
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self.supported_protocols()
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}
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}
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2019-07-04 04:05:01 +00:00
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2019-07-05 08:59:53 +00:00
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/// Implements the encoding per supported protocol for RPCRequest.
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impl RPCRequest {
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2019-08-10 01:44:17 +00:00
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pub fn supported_protocols(&self) -> Vec<ProtocolId> {
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2019-07-05 08:59:53 +00:00
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match self {
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// add more protocols when versions/encodings are supported
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2019-11-27 01:47:46 +00:00
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RPCRequest::Status(_) => vec![ProtocolId::new("status", "1", "ssz")],
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2019-08-29 11:23:28 +00:00
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RPCRequest::Goodbye(_) => vec![ProtocolId::new("goodbye", "1", "ssz")],
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2019-11-27 01:47:46 +00:00
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RPCRequest::BlocksByRange(_) => vec![ProtocolId::new("blocks_by_range", "1", "ssz")],
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RPCRequest::BlocksByRoot(_) => vec![ProtocolId::new("blocks_by_root", "1", "ssz")],
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2019-07-05 08:59:53 +00:00
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}
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}
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2019-11-27 01:47:46 +00:00
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/* These functions are used in the handler for stream management */
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2019-07-16 12:32:37 +00:00
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/// This specifies whether a stream should remain open and await a response, given a request.
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/// A GOODBYE request has no response.
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pub fn expect_response(&self) -> bool {
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2019-07-05 08:59:53 +00:00
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match self {
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2019-11-27 01:47:46 +00:00
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RPCRequest::Status(_) => true,
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RPCRequest::Goodbye(_) => false,
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RPCRequest::BlocksByRange(_) => true,
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RPCRequest::BlocksByRoot(_) => true,
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}
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}
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/// Returns which methods expect multiple responses from the stream. If this is false and
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/// the stream terminates, an error is given.
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pub fn multiple_responses(&self) -> bool {
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match self {
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RPCRequest::Status(_) => false,
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2019-07-16 12:32:37 +00:00
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RPCRequest::Goodbye(_) => false,
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2019-11-27 01:47:46 +00:00
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RPCRequest::BlocksByRange(_) => true,
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RPCRequest::BlocksByRoot(_) => true,
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}
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}
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/// Returns the `ResponseTermination` type associated with the request if a stream gets
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/// terminated.
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pub fn stream_termination(&self) -> ResponseTermination {
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match self {
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// this only gets called after `multiple_responses()` returns true. Therefore, only
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// variants that have `multiple_responses()` can have values.
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RPCRequest::BlocksByRange(_) => ResponseTermination::BlocksByRange,
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RPCRequest::BlocksByRoot(_) => ResponseTermination::BlocksByRoot,
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RPCRequest::Status(_) => unreachable!(),
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RPCRequest::Goodbye(_) => unreachable!(),
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2019-07-05 08:59:53 +00:00
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}
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}
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}
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2019-07-15 07:07:23 +00:00
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/* RPC Response type - used for outbound upgrades */
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2019-07-13 08:35:33 +00:00
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2019-07-09 05:44:23 +00:00
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/* Outbound upgrades */
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2019-07-16 12:32:37 +00:00
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pub type OutboundFramed<TSocket> = Framed<upgrade::Negotiated<TSocket>, OutboundCodec>;
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2019-07-15 08:41:05 +00:00
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2019-07-09 05:44:23 +00:00
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impl<TSocket> OutboundUpgrade<TSocket> for RPCRequest
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where
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TSocket: AsyncRead + AsyncWrite,
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{
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2019-07-15 08:41:05 +00:00
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type Output = OutboundFramed<TSocket>;
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2019-07-09 05:44:23 +00:00
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type Error = RPCError;
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2019-07-15 08:41:05 +00:00
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type Future = sink::Send<OutboundFramed<TSocket>>;
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2019-07-09 05:44:23 +00:00
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fn upgrade_outbound(
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self,
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socket: upgrade::Negotiated<TSocket>,
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protocol: Self::Info,
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) -> Self::Future {
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2019-08-10 01:44:17 +00:00
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match protocol.encoding.as_str() {
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2019-07-15 08:41:05 +00:00
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"ssz" | _ => {
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2019-08-29 11:23:28 +00:00
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let ssz_codec =
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BaseOutboundCodec::new(SSZOutboundCodec::new(protocol, MAX_RPC_SIZE));
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2019-07-15 08:41:05 +00:00
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let codec = OutboundCodec::SSZ(ssz_codec);
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2019-07-15 07:07:23 +00:00
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Framed::new(socket, codec).send(self)
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}
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}
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2019-03-14 14:50:59 +00:00
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}
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}
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2019-07-05 08:59:53 +00:00
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/// Error in RPC Encoding/Decoding.
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2019-03-14 15:48:09 +00:00
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#[derive(Debug)]
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2019-07-05 08:59:53 +00:00
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pub enum RPCError {
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/// Error when reading the packet from the socket.
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2019-03-14 14:50:59 +00:00
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ReadError(upgrade::ReadOneError),
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2019-07-05 08:59:53 +00:00
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/// Error when decoding the raw buffer from ssz.
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2019-03-14 14:50:59 +00:00
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SSZDecodeError(ssz::DecodeError),
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2019-07-09 05:44:23 +00:00
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/// Invalid Protocol ID.
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2019-07-05 08:59:53 +00:00
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InvalidProtocol(&'static str),
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2019-07-09 05:44:23 +00:00
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/// IO Error.
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IoError(io::Error),
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/// Waiting for a request/response timed out, or timer error'd.
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StreamTimeout,
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2019-11-27 01:47:46 +00:00
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/// The peer returned a valid RPCErrorResponse but the response was an error.
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RPCErrorResponse,
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2019-07-05 08:59:53 +00:00
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/// Custom message.
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Custom(String),
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2019-03-14 14:50:59 +00:00
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}
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2019-07-05 08:59:53 +00:00
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impl From<upgrade::ReadOneError> for RPCError {
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2019-03-14 14:50:59 +00:00
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#[inline]
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fn from(err: upgrade::ReadOneError) -> Self {
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2019-07-05 08:59:53 +00:00
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RPCError::ReadError(err)
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2019-03-14 14:50:59 +00:00
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}
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}
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2019-07-05 08:59:53 +00:00
|
|
|
impl From<ssz::DecodeError> for RPCError {
|
2019-03-14 14:50:59 +00:00
|
|
|
#[inline]
|
|
|
|
fn from(err: ssz::DecodeError) -> Self {
|
2019-07-05 08:59:53 +00:00
|
|
|
RPCError::SSZDecodeError(err)
|
2019-03-14 14:50:59 +00:00
|
|
|
}
|
|
|
|
}
|
2019-07-09 05:44:23 +00:00
|
|
|
impl<T> From<tokio::timer::timeout::Error<T>> for RPCError {
|
|
|
|
fn from(err: tokio::timer::timeout::Error<T>) -> Self {
|
|
|
|
if err.is_elapsed() {
|
|
|
|
RPCError::StreamTimeout
|
|
|
|
} else {
|
|
|
|
RPCError::Custom("Stream timer failed".into())
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2019-11-27 01:47:46 +00:00
|
|
|
impl From<()> for RPCError {
|
|
|
|
fn from(_err: ()) -> Self {
|
|
|
|
RPCError::Custom("".into())
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2019-07-09 05:44:23 +00:00
|
|
|
impl From<io::Error> for RPCError {
|
|
|
|
fn from(err: io::Error) -> Self {
|
|
|
|
RPCError::IoError(err)
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
// Error trait is required for `ProtocolsHandler`
|
|
|
|
impl std::fmt::Display for RPCError {
|
|
|
|
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
|
|
|
|
match *self {
|
|
|
|
RPCError::ReadError(ref err) => write!(f, "Error while reading from socket: {}", err),
|
|
|
|
RPCError::SSZDecodeError(ref err) => write!(f, "Error while decoding ssz: {:?}", err),
|
|
|
|
RPCError::InvalidProtocol(ref err) => write!(f, "Invalid Protocol: {}", err),
|
|
|
|
RPCError::IoError(ref err) => write!(f, "IO Error: {}", err),
|
2019-11-27 01:47:46 +00:00
|
|
|
RPCError::RPCErrorResponse => write!(f, "RPC Response Error"),
|
2019-07-09 05:44:23 +00:00
|
|
|
RPCError::StreamTimeout => write!(f, "Stream Timeout"),
|
|
|
|
RPCError::Custom(ref err) => write!(f, "{}", err),
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
impl std::error::Error for RPCError {
|
|
|
|
fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
|
|
|
|
match *self {
|
|
|
|
RPCError::ReadError(ref err) => Some(err),
|
2019-07-16 12:32:37 +00:00
|
|
|
RPCError::SSZDecodeError(_) => None,
|
|
|
|
RPCError::InvalidProtocol(_) => None,
|
2019-07-09 05:44:23 +00:00
|
|
|
RPCError::IoError(ref err) => Some(err),
|
|
|
|
RPCError::StreamTimeout => None,
|
2019-11-27 01:47:46 +00:00
|
|
|
RPCError::RPCErrorResponse => None,
|
2019-07-16 12:32:37 +00:00
|
|
|
RPCError::Custom(_) => None,
|
2019-07-09 05:44:23 +00:00
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
2019-09-02 21:50:44 +00:00
|
|
|
|
|
|
|
impl std::fmt::Display for RPCRequest {
|
|
|
|
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
|
|
|
|
match self {
|
2019-11-27 01:47:46 +00:00
|
|
|
RPCRequest::Status(status) => write!(f, "Status Message: {}", status),
|
2019-09-02 21:50:44 +00:00
|
|
|
RPCRequest::Goodbye(reason) => write!(f, "Goodbye: {}", reason),
|
2019-11-27 01:47:46 +00:00
|
|
|
RPCRequest::BlocksByRange(req) => write!(f, "Blocks by range: {}", req),
|
|
|
|
RPCRequest::BlocksByRoot(req) => write!(f, "Blocks by root: {:?}", req),
|
2019-09-02 21:50:44 +00:00
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|