go-pulse/contracts/release/release.go
Felix Lange c213fd1fd8 all: import "context" instead of "golang.org/x/net/context"
There is no need to depend on the old context package now that the
minimum Go version is 1.7. The move to "context" eliminates our weird
vendoring setup. Some vendored code still uses golang.org/x/net/context
and it is now vendored in the normal way.

This change triggered new vet checks around context.WithTimeout which
didn't fire with golang.org/x/net/context.
2017-03-22 20:49:15 +01:00

165 lines
5.8 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 release contains the node service that tracks client releases.
package release
//go:generate abigen --sol ./contract.sol --pkg release --out ./contract.go
import (
"context"
"fmt"
"strings"
"time"
"github.com/ethereum/go-ethereum/accounts/abi/bind"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/eth"
"github.com/ethereum/go-ethereum/internal/ethapi"
"github.com/ethereum/go-ethereum/les"
"github.com/ethereum/go-ethereum/log"
"github.com/ethereum/go-ethereum/node"
"github.com/ethereum/go-ethereum/p2p"
"github.com/ethereum/go-ethereum/rpc"
)
// Interval to check for new releases
const releaseRecheckInterval = time.Hour
// Config contains the configurations of the release service.
type Config struct {
Oracle common.Address // Ethereum address of the release oracle
Major uint32 // Major version component of the release
Minor uint32 // Minor version component of the release
Patch uint32 // Patch version component of the release
Commit [20]byte // Git SHA1 commit hash of the release
}
// ReleaseService is a node service that periodically checks the blockchain for
// newly released versions of the client being run and issues a warning to the
// user about it.
type ReleaseService struct {
config Config // Current version to check releases against
oracle *ReleaseOracle // Native binding to the release oracle contract
quit chan chan error // Quit channel to terminate the version checker
}
// NewReleaseService creates a new service to periodically check for new client
// releases and notify the user of such.
func NewReleaseService(ctx *node.ServiceContext, config Config) (node.Service, error) {
// Retrieve the Ethereum service dependency to access the blockchain
var apiBackend ethapi.Backend
var ethereum *eth.Ethereum
if err := ctx.Service(&ethereum); err == nil {
apiBackend = ethereum.ApiBackend
} else {
var ethereum *les.LightEthereum
if err := ctx.Service(&ethereum); err == nil {
apiBackend = ethereum.ApiBackend
} else {
return nil, err
}
}
// Construct the release service
contract, err := NewReleaseOracle(config.Oracle, eth.NewContractBackend(apiBackend))
if err != nil {
return nil, err
}
return &ReleaseService{
config: config,
oracle: contract,
quit: make(chan chan error),
}, nil
}
// Protocols returns an empty list of P2P protocols as the release service does
// not have a networking component.
func (r *ReleaseService) Protocols() []p2p.Protocol { return nil }
// APIs returns an empty list of RPC descriptors as the release service does not
// expose any functioanlity to the outside world.
func (r *ReleaseService) APIs() []rpc.API { return nil }
// Start spawns the periodic version checker goroutine
func (r *ReleaseService) Start(server *p2p.Server) error {
go r.checker()
return nil
}
// Stop terminates all goroutines belonging to the service, blocking until they
// are all terminated.
func (r *ReleaseService) Stop() error {
errc := make(chan error)
r.quit <- errc
return <-errc
}
// checker runs indefinitely in the background, periodically checking for new
// client releases.
func (r *ReleaseService) checker() {
// Set up the timers to periodically check for releases
timer := time.NewTimer(0) // Immediately fire a version check
defer timer.Stop()
for {
select {
case <-timer.C:
// Rechedule the timer before continuing
timer.Reset(releaseRecheckInterval)
r.checkVersion()
case errc := <-r.quit:
errc <- nil
return
}
}
}
func (r *ReleaseService) checkVersion() {
// Retrieve the current version, and handle missing contracts gracefully
ctx, cancel := context.WithTimeout(context.Background(), time.Second*5)
opts := &bind.CallOpts{Context: ctx}
defer cancel()
version, err := r.oracle.CurrentVersion(opts)
if err != nil {
if err == bind.ErrNoCode {
log.Debug("Release oracle not found", "contract", r.config.Oracle)
} else {
log.Error("Failed to retrieve current release", "err", err)
}
return
}
// Version was successfully retrieved, notify if newer than ours
if version.Major > r.config.Major ||
(version.Major == r.config.Major && version.Minor > r.config.Minor) ||
(version.Major == r.config.Major && version.Minor == r.config.Minor && version.Patch > r.config.Patch) {
warning := fmt.Sprintf("Client v%d.%d.%d-%x seems older than the latest upstream release v%d.%d.%d-%x",
r.config.Major, r.config.Minor, r.config.Patch, r.config.Commit[:4], version.Major, version.Minor, version.Patch, version.Commit[:4])
howtofix := fmt.Sprintf("Please check https://github.com/ethereum/go-ethereum/releases for new releases")
separator := strings.Repeat("-", len(warning))
log.Warn(separator)
log.Warn(warning)
log.Warn(howtofix)
log.Warn(separator)
} else {
log.Debug("Client seems up to date with upstream",
"local", fmt.Sprintf("v%d.%d.%d-%x", r.config.Major, r.config.Minor, r.config.Patch, r.config.Commit[:4]),
"upstream", fmt.Sprintf("v%d.%d.%d-%x", version.Major, version.Minor, version.Patch, version.Commit[:4]))
}
}