• rene's avatar
    node: refactor package node (#21105) · c0c01612
    rene authored
    This PR significantly changes the APIs for instantiating Ethereum nodes in
    a Go program. The new APIs are not backwards-compatible, but we feel that
    this is made up for by the much simpler way of registering services on
    node.Node. You can find more information and rationale in the design
    document: https://gist.github.com/renaynay/5bec2de19fde66f4d04c535fd24f0775.
    
    There is also a new feature in Node's Go API: it is now possible to
    register arbitrary handlers on the user-facing HTTP server. In geth, this
    facility is used to enable GraphQL.
    
    There is a single minor change relevant for geth users in this PR: The
    GraphQL API is no longer available separately from the JSON-RPC HTTP
    server. If you want GraphQL, you need to enable it using the
    ./geth --http --graphql flag combination.
    
    The --graphql.port and --graphql.addr flags are no longer available.
    c0c01612
endpoints.go 3.11 KB
// Copyright 2018 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 node

import (
	"net"
	"net/http"
	"time"

	"github.com/ethereum/go-ethereum/log"
	"github.com/ethereum/go-ethereum/rpc"
)

// StartHTTPEndpoint starts the HTTP RPC endpoint.
func StartHTTPEndpoint(endpoint string, timeouts rpc.HTTPTimeouts, handler http.Handler) (*http.Server, net.Addr, error) {
	// start the HTTP listener
	var (
		listener net.Listener
		err      error
	)
	if listener, err = net.Listen("tcp", endpoint); err != nil {
		return nil, nil, err
	}
	// make sure timeout values are meaningful
	CheckTimeouts(&timeouts)
	// Bundle and start the HTTP server
	httpSrv := &http.Server{
		Handler:      handler,
		ReadTimeout:  timeouts.ReadTimeout,
		WriteTimeout: timeouts.WriteTimeout,
		IdleTimeout:  timeouts.IdleTimeout,
	}
	go httpSrv.Serve(listener)
	return httpSrv, listener.Addr(), err
}

// checkModuleAvailability checks that all names given in modules are actually
// available API services. It assumes that the MetadataApi module ("rpc") is always available;
// the registration of this "rpc" module happens in NewServer() and is thus common to all endpoints.
func checkModuleAvailability(modules []string, apis []rpc.API) (bad, available []string) {
	availableSet := make(map[string]struct{})
	for _, api := range apis {
		if _, ok := availableSet[api.Namespace]; !ok {
			availableSet[api.Namespace] = struct{}{}
			available = append(available, api.Namespace)
		}
	}
	for _, name := range modules {
		if _, ok := availableSet[name]; !ok && name != rpc.MetadataApi {
			bad = append(bad, name)
		}
	}
	return bad, available
}

// CheckTimeouts ensures that timeout values are meaningful
func CheckTimeouts(timeouts *rpc.HTTPTimeouts) {
	if timeouts.ReadTimeout < time.Second {
		log.Warn("Sanitizing invalid HTTP read timeout", "provided", timeouts.ReadTimeout, "updated", rpc.DefaultHTTPTimeouts.ReadTimeout)
		timeouts.ReadTimeout = rpc.DefaultHTTPTimeouts.ReadTimeout
	}
	if timeouts.WriteTimeout < time.Second {
		log.Warn("Sanitizing invalid HTTP write timeout", "provided", timeouts.WriteTimeout, "updated", rpc.DefaultHTTPTimeouts.WriteTimeout)
		timeouts.WriteTimeout = rpc.DefaultHTTPTimeouts.WriteTimeout
	}
	if timeouts.IdleTimeout < time.Second {
		log.Warn("Sanitizing invalid HTTP idle timeout", "provided", timeouts.IdleTimeout, "updated", rpc.DefaultHTTPTimeouts.IdleTimeout)
		timeouts.IdleTimeout = rpc.DefaultHTTPTimeouts.IdleTimeout
	}
}