plugeth/p2p/testing/protocolsession.go
Felix Lange 30cd5c1854
all: new p2p node representation (#17643)
Package p2p/enode provides a generalized representation of p2p nodes
which can contain arbitrary information in key/value pairs. It is also
the new home for the node database. The "v4" identity scheme is also
moved here from p2p/enr to remove the dependency on Ethereum crypto from
that package.

Record signature handling is changed significantly. The identity scheme
registry is removed and acceptable schemes must be passed to any method
that needs identity. This means records must now be validated explicitly
after decoding.

The enode API is designed to make signature handling easy and safe: most
APIs around the codebase work with enode.Node, which is a wrapper around
a valid record. Going from enr.Record to enode.Node requires a valid
signature.

* p2p/discover: port to p2p/enode

This ports the discovery code to the new node representation in
p2p/enode. The wire protocol is unchanged, this can be considered a
refactoring change. The Kademlia table can now deal with nodes using an
arbitrary identity scheme. This requires a few incompatible API changes:

  - Table.Lookup is not available anymore. It used to take a public key
    as argument because v4 protocol requires one. Its replacement is
    LookupRandom.
  - Table.Resolve takes *enode.Node instead of NodeID. This is also for
    v4 protocol compatibility because nodes cannot be looked up by ID
    alone.
  - Types Node and NodeID are gone. Further commits in the series will be
    fixes all over the the codebase to deal with those removals.

* p2p: port to p2p/enode and discovery changes

This adapts package p2p to the changes in p2p/discover. All uses of
discover.Node and discover.NodeID are replaced by their equivalents from
p2p/enode.

New API is added to retrieve the enode.Node instance of a peer. The
behavior of Server.Self with discovery disabled is improved. It now
tries much harder to report a working IP address, falling back to
127.0.0.1 if no suitable address can be determined through other means.
These changes were needed for tests of other packages later in the
series.

* p2p/simulations, p2p/testing: port to p2p/enode

No surprises here, mostly replacements of discover.Node, discover.NodeID
with their new equivalents. The 'interesting' API changes are:

 - testing.ProtocolSession tracks complete nodes, not just their IDs.
 - adapters.NodeConfig has a new method to create a complete node.

These changes were needed to make swarm tests work.

Note that the NodeID change makes the code incompatible with old
simulation snapshots.

* whisper/whisperv5, whisper/whisperv6: port to p2p/enode

This port was easy because whisper uses []byte for node IDs and
URL strings in the API.

* eth: port to p2p/enode

Again, easy to port because eth uses strings for node IDs and doesn't
care about node information in any way.

* les: port to p2p/enode

Apart from replacing discover.NodeID with enode.ID, most changes are in
the server pool code. It now deals with complete nodes instead
of (Pubkey, IP, Port) triples. The database format is unchanged for now,
but we should probably change it to use the node database later.

* node: port to p2p/enode

This change simply replaces discover.Node and discover.NodeID with their
new equivalents.

* swarm/network: port to p2p/enode

Swarm has its own node address representation, BzzAddr, containing both
an overlay address (the hash of a secp256k1 public key) and an underlay
address (enode:// URL).

There are no changes to the BzzAddr format in this commit, but certain
operations such as creating a BzzAddr from a node ID are now impossible
because node IDs aren't public keys anymore.

Most swarm-related changes in the series remove uses of
NewAddrFromNodeID, replacing it with NewAddr which takes a complete node
as argument. ToOverlayAddr is removed because we can just use the node
ID directly.
2018-09-25 00:59:00 +02:00

283 lines
7.8 KiB
Go

// Copyright 2017 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 testing
import (
"errors"
"fmt"
"sync"
"time"
"github.com/ethereum/go-ethereum/log"
"github.com/ethereum/go-ethereum/p2p"
"github.com/ethereum/go-ethereum/p2p/enode"
"github.com/ethereum/go-ethereum/p2p/simulations/adapters"
)
var errTimedOut = errors.New("timed out")
// ProtocolSession is a quasi simulation of a pivot node running
// a service and a number of dummy peers that can send (trigger) or
// receive (expect) messages
type ProtocolSession struct {
Server *p2p.Server
Nodes []*enode.Node
adapter *adapters.SimAdapter
events chan *p2p.PeerEvent
}
// Exchange is the basic units of protocol tests
// the triggers and expects in the arrays are run immediately and asynchronously
// thus one cannot have multiple expects for the SAME peer with DIFFERENT message types
// because it's unpredictable which expect will receive which message
// (with expect #1 and #2, messages might be sent #2 and #1, and both expects will complain about wrong message code)
// an exchange is defined on a session
type Exchange struct {
Label string
Triggers []Trigger
Expects []Expect
Timeout time.Duration
}
// Trigger is part of the exchange, incoming message for the pivot node
// sent by a peer
type Trigger struct {
Msg interface{} // type of message to be sent
Code uint64 // code of message is given
Peer enode.ID // the peer to send the message to
Timeout time.Duration // timeout duration for the sending
}
// Expect is part of an exchange, outgoing message from the pivot node
// received by a peer
type Expect struct {
Msg interface{} // type of message to expect
Code uint64 // code of message is now given
Peer enode.ID // the peer that expects the message
Timeout time.Duration // timeout duration for receiving
}
// Disconnect represents a disconnect event, used and checked by TestDisconnected
type Disconnect struct {
Peer enode.ID // discconnected peer
Error error // disconnect reason
}
// trigger sends messages from peers
func (s *ProtocolSession) trigger(trig Trigger) error {
simNode, ok := s.adapter.GetNode(trig.Peer)
if !ok {
return fmt.Errorf("trigger: peer %v does not exist (1- %v)", trig.Peer, len(s.Nodes))
}
mockNode, ok := simNode.Services()[0].(*mockNode)
if !ok {
return fmt.Errorf("trigger: peer %v is not a mock", trig.Peer)
}
errc := make(chan error)
go func() {
log.Trace(fmt.Sprintf("trigger %v (%v)....", trig.Msg, trig.Code))
errc <- mockNode.Trigger(&trig)
log.Trace(fmt.Sprintf("triggered %v (%v)", trig.Msg, trig.Code))
}()
t := trig.Timeout
if t == time.Duration(0) {
t = 1000 * time.Millisecond
}
select {
case err := <-errc:
return err
case <-time.After(t):
return fmt.Errorf("timout expecting %v to send to peer %v", trig.Msg, trig.Peer)
}
}
// expect checks an expectation of a message sent out by the pivot node
func (s *ProtocolSession) expect(exps []Expect) error {
// construct a map of expectations for each node
peerExpects := make(map[enode.ID][]Expect)
for _, exp := range exps {
if exp.Msg == nil {
return errors.New("no message to expect")
}
peerExpects[exp.Peer] = append(peerExpects[exp.Peer], exp)
}
// construct a map of mockNodes for each node
mockNodes := make(map[enode.ID]*mockNode)
for nodeID := range peerExpects {
simNode, ok := s.adapter.GetNode(nodeID)
if !ok {
return fmt.Errorf("trigger: peer %v does not exist (1- %v)", nodeID, len(s.Nodes))
}
mockNode, ok := simNode.Services()[0].(*mockNode)
if !ok {
return fmt.Errorf("trigger: peer %v is not a mock", nodeID)
}
mockNodes[nodeID] = mockNode
}
// done chanell cancels all created goroutines when function returns
done := make(chan struct{})
defer close(done)
// errc catches the first error from
errc := make(chan error)
wg := &sync.WaitGroup{}
wg.Add(len(mockNodes))
for nodeID, mockNode := range mockNodes {
nodeID := nodeID
mockNode := mockNode
go func() {
defer wg.Done()
// Sum all Expect timeouts to give the maximum
// time for all expectations to finish.
// mockNode.Expect checks all received messages against
// a list of expected messages and timeout for each
// of them can not be checked separately.
var t time.Duration
for _, exp := range peerExpects[nodeID] {
if exp.Timeout == time.Duration(0) {
t += 2000 * time.Millisecond
} else {
t += exp.Timeout
}
}
alarm := time.NewTimer(t)
defer alarm.Stop()
// expectErrc is used to check if error returned
// from mockNode.Expect is not nil and to send it to
// errc only in that case.
// done channel will be closed when function
expectErrc := make(chan error)
go func() {
select {
case expectErrc <- mockNode.Expect(peerExpects[nodeID]...):
case <-done:
case <-alarm.C:
}
}()
select {
case err := <-expectErrc:
if err != nil {
select {
case errc <- err:
case <-done:
case <-alarm.C:
errc <- errTimedOut
}
}
case <-done:
case <-alarm.C:
errc <- errTimedOut
}
}()
}
go func() {
wg.Wait()
// close errc when all goroutines finish to return nill err from errc
close(errc)
}()
return <-errc
}
// TestExchanges tests a series of exchanges against the session
func (s *ProtocolSession) TestExchanges(exchanges ...Exchange) error {
for i, e := range exchanges {
if err := s.testExchange(e); err != nil {
return fmt.Errorf("exchange #%d %q: %v", i, e.Label, err)
}
log.Trace(fmt.Sprintf("exchange #%d %q: run successfully", i, e.Label))
}
return nil
}
// testExchange tests a single Exchange.
// Default timeout value is 2 seconds.
func (s *ProtocolSession) testExchange(e Exchange) error {
errc := make(chan error)
done := make(chan struct{})
defer close(done)
go func() {
for _, trig := range e.Triggers {
err := s.trigger(trig)
if err != nil {
errc <- err
return
}
}
select {
case errc <- s.expect(e.Expects):
case <-done:
}
}()
// time out globally or finish when all expectations satisfied
t := e.Timeout
if t == 0 {
t = 2000 * time.Millisecond
}
alarm := time.NewTimer(t)
select {
case err := <-errc:
return err
case <-alarm.C:
return errTimedOut
}
}
// TestDisconnected tests the disconnections given as arguments
// the disconnect structs describe what disconnect error is expected on which peer
func (s *ProtocolSession) TestDisconnected(disconnects ...*Disconnect) error {
expects := make(map[enode.ID]error)
for _, disconnect := range disconnects {
expects[disconnect.Peer] = disconnect.Error
}
timeout := time.After(time.Second)
for len(expects) > 0 {
select {
case event := <-s.events:
if event.Type != p2p.PeerEventTypeDrop {
continue
}
expectErr, ok := expects[event.Peer]
if !ok {
continue
}
if !(expectErr == nil && event.Error == "" || expectErr != nil && expectErr.Error() == event.Error) {
return fmt.Errorf("unexpected error on peer %v. expected '%v', got '%v'", event.Peer, expectErr, event.Error)
}
delete(expects, event.Peer)
case <-timeout:
return fmt.Errorf("timed out waiting for peers to disconnect")
}
}
return nil
}