From d235e2c6a5788ec4a6cff15a16f56b38a3876a0d Mon Sep 17 00:00:00 2001 From: Determinant Date: Sun, 28 Jun 2020 14:47:41 -0400 Subject: ... --- rpc/server.go | 147 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 147 insertions(+) create mode 100644 rpc/server.go (limited to 'rpc/server.go') diff --git a/rpc/server.go b/rpc/server.go new file mode 100644 index 0000000..bf5d93e --- /dev/null +++ b/rpc/server.go @@ -0,0 +1,147 @@ +// 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 . + +package rpc + +import ( + "context" + "io" + "sync/atomic" + + mapset "github.com/deckarep/golang-set" + "github.com/ava-labs/go-ethereum/log" +) + +const MetadataApi = "rpc" + +// CodecOption specifies which type of messages a codec supports. +// +// Deprecated: this option is no longer honored by Server. +type CodecOption int + +const ( + // OptionMethodInvocation is an indication that the codec supports RPC method calls + OptionMethodInvocation CodecOption = 1 << iota + + // OptionSubscriptions is an indication that the codec suports RPC notifications + OptionSubscriptions = 1 << iota // support pub sub +) + +// Server is an RPC server. +type Server struct { + services serviceRegistry + idgen func() ID + run int32 + codecs mapset.Set +} + +// NewServer creates a new server instance with no registered handlers. +func NewServer() *Server { + server := &Server{idgen: randomIDGenerator(), codecs: mapset.NewSet(), run: 1} + // Register the default service providing meta information about the RPC service such + // as the services and methods it offers. + rpcService := &RPCService{server} + server.RegisterName(MetadataApi, rpcService) + return server +} + +// RegisterName creates a service for the given receiver type under the given name. When no +// methods on the given receiver match the criteria to be either a RPC method or a +// subscription an error is returned. Otherwise a new service is created and added to the +// service collection this server provides to clients. +func (s *Server) RegisterName(name string, receiver interface{}) error { + return s.services.registerName(name, receiver) +} + +// ServeCodec reads incoming requests from codec, calls the appropriate callback and writes +// the response back using the given codec. It will block until the codec is closed or the +// server is stopped. In either case the codec is closed. +// +// Note that codec options are no longer supported. +func (s *Server) ServeCodec(codec ServerCodec, options CodecOption) { + defer codec.Close() + + // Don't serve if server is stopped. + if atomic.LoadInt32(&s.run) == 0 { + return + } + + // Add the codec to the set so it can be closed by Stop. + s.codecs.Add(codec) + defer s.codecs.Remove(codec) + + c := initClient(codec, s.idgen, &s.services) + <-codec.Closed() + c.Close() +} + +// serveSingleRequest reads and processes a single RPC request from the given codec. This +// is used to serve HTTP connections. Subscriptions and reverse calls are not allowed in +// this mode. +func (s *Server) serveSingleRequest(ctx context.Context, codec ServerCodec) { + // Don't serve if server is stopped. + if atomic.LoadInt32(&s.run) == 0 { + return + } + + h := newHandler(ctx, codec, s.idgen, &s.services) + h.allowSubscribe = false + defer h.close(io.EOF, nil) + + reqs, batch, err := codec.Read() + if err != nil { + if err != io.EOF { + codec.Write(ctx, errorMessage(&invalidMessageError{"parse error"})) + } + return + } + if batch { + h.handleBatch(reqs) + } else { + h.handleMsg(reqs[0]) + } +} + +// Stop stops reading new requests, waits for stopPendingRequestTimeout to allow pending +// requests to finish, then closes all codecs which will cancel pending requests and +// subscriptions. +func (s *Server) Stop() { + if atomic.CompareAndSwapInt32(&s.run, 1, 0) { + log.Debug("RPC server shutting down") + s.codecs.Each(func(c interface{}) bool { + c.(ServerCodec).Close() + return true + }) + } +} + +// RPCService gives meta information about the server. +// e.g. gives information about the loaded modules. +type RPCService struct { + server *Server +} + +// Modules returns the list of RPC services with their version number +func (s *RPCService) Modules() map[string]string { + s.server.services.mu.Lock() + defer s.server.services.mu.Unlock() + + modules := make(map[string]string) + for name := range s.server.services.services { + modules[name] = "1.0" + } + return modules +} -- cgit v1.2.3