plugeth/rpc/ipc.go
Felix Lange 245f3146c2
rpc: implement full bi-directional communication (#18471)
New APIs added:

    client.RegisterName(namespace, service) // makes service available to server
    client.Notify(ctx, method, args...)     // sends a notification
    ClientFromContext(ctx)                  // to get a client in handler method

This is essentially a rewrite of the server-side code. JSON-RPC
processing code is now the same on both server and client side. Many
minor issues were fixed in the process and there is a new test suite for
JSON-RPC spec compliance (and non-compliance in some cases).

List of behavior changes:

- Method handlers are now called with a per-request context instead of a
  per-connection context. The context is canceled right after the method
  returns.
- Subscription error channels are always closed when the connection
  ends. There is no need to also wait on the Notifier's Closed channel
  to detect whether the subscription has ended.
- Client now omits "params" instead of sending "params": null when there
  are no arguments to a call. The previous behavior was not compliant
  with the spec. The server still accepts "params": null.
- Floating point numbers are allowed as "id". The spec doesn't allow
  them, but we handle request "id" as json.RawMessage and guarantee that
  the same number will be sent back.
- Logging is improved significantly. There is now a message at DEBUG
  level for each RPC call served.
2019-02-04 13:47:34 +01:00

57 lines
1.9 KiB
Go

// Copyright 2015 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
package rpc
import (
"context"
"net"
"github.com/ethereum/go-ethereum/log"
"github.com/ethereum/go-ethereum/p2p/netutil"
)
// ServeListener accepts connections on l, serving JSON-RPC on them.
func (s *Server) ServeListener(l net.Listener) error {
for {
conn, err := l.Accept()
if netutil.IsTemporaryError(err) {
log.Warn("RPC accept error", "err", err)
continue
} else if err != nil {
return err
}
log.Trace("Accepted RPC connection", "conn", conn.RemoteAddr())
go s.ServeCodec(NewJSONCodec(conn), OptionMethodInvocation|OptionSubscriptions)
}
}
// DialIPC create a new IPC client that connects to the given endpoint. On Unix it assumes
// the endpoint is the full path to a unix socket, and Windows the endpoint is an
// identifier for a named pipe.
//
// The context is used for the initial connection establishment. It does not
// affect subsequent interactions with the client.
func DialIPC(ctx context.Context, endpoint string) (*Client, error) {
return newClient(ctx, func(ctx context.Context) (ServerCodec, error) {
conn, err := newIPCConnection(ctx, endpoint)
if err != nil {
return nil, err
}
return NewJSONCodec(conn), err
})
}