Merge pull request #1970 from karalabe/customizable-protocol-stacks

Customizable protocol stacks

1 files changed, 496 insertions, 0 deletions

diff --git a/node/node_test.go b/node/node_test.go
new file mode 100644
index 000000000..ef096fc91
--- /dev/null
+++ b/node/node_test.go
@@ -0,0 +1,496 @@
+// 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 node
+
+import (
+	"errors"
+	"io/ioutil"
+	"os"
+	"reflect"
+	"testing"
+
+	"github.com/ethereum/go-ethereum/crypto"
+	"github.com/ethereum/go-ethereum/p2p"
+)
+
+var (
+	testNodeKey, _ = crypto.GenerateKey()
+
+	testNodeConfig = &Config{
+		PrivateKey: testNodeKey,
+		Name:       "test node",
+	}
+)
+
+// Tests that an empty protocol stack can be started, restarted and stopped.
+func TestNodeLifeCycle(t *testing.T) {
+	stack, err := New(testNodeConfig)
+	if err != nil {
+		t.Fatalf("failed to create protocol stack: %v", err)
+	}
+	// Ensure that a stopped node can be stopped again
+	for i := 0; i < 3; i++ {
+		if err := stack.Stop(); err != ErrNodeStopped {
+			t.Fatalf("iter %d: stop failure mismatch: have %v, want %v", i, err, ErrNodeStopped)
+		}
+	}
+	// Ensure that a node can be successfully started, but only once
+	if err := stack.Start(); err != nil {
+		t.Fatalf("failed to start node: %v", err)
+	}
+	if err := stack.Start(); err != ErrNodeRunning {
+		t.Fatalf("start failure mismatch: have %v, want %v ", err, ErrNodeRunning)
+	}
+	// Ensure that a node can be restarted arbitrarily many times
+	for i := 0; i < 3; i++ {
+		if err := stack.Restart(); err != nil {
+			t.Fatalf("iter %d: failed to restart node: %v", i, err)
+		}
+	}
+	// Ensure that a node can be stopped, but only once
+	if err := stack.Stop(); err != nil {
+		t.Fatalf("failed to stop node: %v", err)
+	}
+	if err := stack.Stop(); err != ErrNodeStopped {
+		t.Fatalf("stop failure mismatch: have %v, want %v ", err, ErrNodeStopped)
+	}
+}
+
+// Tests that if the data dir is already in use, an appropriate error is returned.
+func TestNodeUsedDataDir(t *testing.T) {
+	// Create a temporary folder to use as the data directory
+	dir, err := ioutil.TempDir("", "")
+	if err != nil {
+		t.Fatalf("failed to create temporary data directory: %v", err)
+	}
+	defer os.RemoveAll(dir)
+
+	// Create a new node based on the data directory
+	original, err := New(&Config{DataDir: dir})
+	if err != nil {
+		t.Fatalf("failed to create original protocol stack: %v", err)
+	}
+	if err := original.Start(); err != nil {
+		t.Fatalf("failed to start original protocol stack: %v", err)
+	}
+	defer original.Stop()
+
+	// Create a second node based on the same data directory and ensure failure
+	duplicate, err := New(&Config{DataDir: dir})
+	if err != nil {
+		t.Fatalf("failed to create duplicate protocol stack: %v", err)
+	}
+	if err := duplicate.Start(); err != ErrDatadirUsed {
+		t.Fatalf("duplicate datadir failure mismatch: have %v, want %v", err, ErrDatadirUsed)
+	}
+}
+
+// Tests whether services can be registered and duplicates caught.
+func TestServiceRegistry(t *testing.T) {
+	stack, err := New(testNodeConfig)
+	if err != nil {
+		t.Fatalf("failed to create protocol stack: %v", err)
+	}
+	// Register a batch of unique services and ensure they start successfully
+	services := []ServiceConstructor{NewNoopServiceA, NewNoopServiceB, NewNoopServiceC}
+	for i, constructor := range services {
+		if err := stack.Register(constructor); err != nil {
+			t.Fatalf("service #%d: registration failed: %v", i, err)
+		}
+	}
+	if err := stack.Start(); err != nil {
+		t.Fatalf("failed to start original service stack: %v", err)
+	}
+	if err := stack.Stop(); err != nil {
+		t.Fatalf("failed to stop original service stack: %v", err)
+	}
+	// Duplicate one of the services and retry starting the node
+	if err := stack.Register(NewNoopServiceB); err != nil {
+		t.Fatalf("duplicate registration failed: %v", err)
+	}
+	if err := stack.Start(); err == nil {
+		t.Fatalf("duplicate service started")
+	} else {
+		if _, ok := err.(*DuplicateServiceError); !ok {
+			t.Fatalf("duplicate error mismatch: have %v, want %v", err, DuplicateServiceError{})
+		}
+	}
+}
+
+// Tests that registered services get started and stopped correctly.
+func TestServiceLifeCycle(t *testing.T) {
+	stack, err := New(testNodeConfig)
+	if err != nil {
+		t.Fatalf("failed to create protocol stack: %v", err)
+	}
+	// Register a batch of life-cycle instrumented services
+	services := map[string]InstrumentingWrapper{
+		"A": InstrumentedServiceMakerA,
+		"B": InstrumentedServiceMakerB,
+		"C": InstrumentedServiceMakerC,
+	}
+	started := make(map[string]bool)
+	stopped := make(map[string]bool)
+
+	for id, maker := range services {
+		id := id // Closure for the constructor
+		constructor := func(*ServiceContext) (Service, error) {
+			return &InstrumentedService{
+				startHook: func(*p2p.Server) { started[id] = true },
+				stopHook:  func() { stopped[id] = true },
+			}, nil
+		}
+		if err := stack.Register(maker(constructor)); err != nil {
+			t.Fatalf("service %s: registration failed: %v", id, err)
+		}
+	}
+	// Start the node and check that all services are running
+	if err := stack.Start(); err != nil {
+		t.Fatalf("failed to start protocol stack: %v", err)
+	}
+	for id, _ := range services {
+		if !started[id] {
+			t.Fatalf("service %s: freshly started service not running", id)
+		}
+		if stopped[id] {
+			t.Fatalf("service %s: freshly started service already stopped", id)
+		}
+	}
+	// Stop the node and check that all services have been stopped
+	if err := stack.Stop(); err != nil {
+		t.Fatalf("failed to stop protocol stack: %v", err)
+	}
+	for id, _ := range services {
+		if !stopped[id] {
+			t.Fatalf("service %s: freshly terminated service still running", id)
+		}
+	}
+}
+
+// Tests that services are restarted cleanly as new instances.
+func TestServiceRestarts(t *testing.T) {
+	stack, err := New(testNodeConfig)
+	if err != nil {
+		t.Fatalf("failed to create protocol stack: %v", err)
+	}
+	// Define a service that does not support restarts
+	var (
+		running bool
+		started int
+	)
+	constructor := func(*ServiceContext) (Service, error) {
+		running = false
+
+		return &InstrumentedService{
+			startHook: func(*p2p.Server) {
+				if running {
+					panic("already running")
+				}
+				running = true
+				started++
+			},
+		}, nil
+	}
+	// Register the service and start the protocol stack
+	if err := stack.Register(constructor); err != nil {
+		t.Fatalf("failed to register the service: %v", err)
+	}
+	if err := stack.Start(); err != nil {
+		t.Fatalf("failed to start protocol stack: %v", err)
+	}
+	defer stack.Stop()
+
+	if running != true || started != 1 {
+		t.Fatalf("running/started mismatch: have %v/%d, want true/1", running, started)
+	}
+	// Restart the stack a few times and check successful service restarts
+	for i := 0; i < 3; i++ {
+		if err := stack.Restart(); err != nil {
+			t.Fatalf("iter %d: failed to restart stack: %v", i, err)
+		}
+	}
+	if running != true || started != 4 {
+		t.Fatalf("running/started mismatch: have %v/%d, want true/4", running, started)
+	}
+}
+
+// Tests that if a service fails to initialize itself, none of the other services
+// will be allowed to even start.
+func TestServiceConstructionAbortion(t *testing.T) {
+	stack, err := New(testNodeConfig)
+	if err != nil {
+		t.Fatalf("failed to create protocol stack: %v", err)
+	}
+	// Define a batch of good services
+	services := map[string]InstrumentingWrapper{
+		"A": InstrumentedServiceMakerA,
+		"B": InstrumentedServiceMakerB,
+		"C": InstrumentedServiceMakerC,
+	}
+	started := make(map[string]bool)
+	for id, maker := range services {
+		id := id // Closure for the constructor
+		constructor := func(*ServiceContext) (Service, error) {
+			return &InstrumentedService{
+				startHook: func(*p2p.Server) { started[id] = true },
+			}, nil
+		}
+		if err := stack.Register(maker(constructor)); err != nil {
+			t.Fatalf("service %s: registration failed: %v", id, err)
+		}
+	}
+	// Register a service that fails to construct itself
+	failure := errors.New("fail")
+	failer := func(*ServiceContext) (Service, error) {
+		return nil, failure
+	}
+	if err := stack.Register(failer); err != nil {
+		t.Fatalf("failer registration failed: %v", err)
+	}
+	// Start the protocol stack and ensure none of the services get started
+	for i := 0; i < 100; i++ {
+		if err := stack.Start(); err != failure {
+			t.Fatalf("iter %d: stack startup failure mismatch: have %v, want %v", i, err, failure)
+		}
+		for id, _ := range services {
+			if started[id] {
+				t.Fatalf("service %s: started should not have", id)
+			}
+			delete(started, id)
+		}
+	}
+}
+
+// Tests that if a service fails to start, all others started before it will be
+// shut down.
+func TestServiceStartupAbortion(t *testing.T) {
+	stack, err := New(testNodeConfig)
+	if err != nil {
+		t.Fatalf("failed to create protocol stack: %v", err)
+	}
+	// Register a batch of good services
+	services := map[string]InstrumentingWrapper{
+		"A": InstrumentedServiceMakerA,
+		"B": InstrumentedServiceMakerB,
+		"C": InstrumentedServiceMakerC,
+	}
+	started := make(map[string]bool)
+	stopped := make(map[string]bool)
+
+	for id, maker := range services {
+		id := id // Closure for the constructor
+		constructor := func(*ServiceContext) (Service, error) {
+			return &InstrumentedService{
+				startHook: func(*p2p.Server) { started[id] = true },
+				stopHook:  func() { stopped[id] = true },
+			}, nil
+		}
+		if err := stack.Register(maker(constructor)); err != nil {
+			t.Fatalf("service %s: registration failed: %v", id, err)
+		}
+	}
+	// Register a service that fails to start
+	failure := errors.New("fail")
+	failer := func(*ServiceContext) (Service, error) {
+		return &InstrumentedService{
+			start: failure,
+		}, nil
+	}
+	if err := stack.Register(failer); err != nil {
+		t.Fatalf("failer registration failed: %v", err)
+	}
+	// Start the protocol stack and ensure all started services stop
+	for i := 0; i < 100; i++ {
+		if err := stack.Start(); err != failure {
+			t.Fatalf("iter %d: stack startup failure mismatch: have %v, want %v", i, err, failure)
+		}
+		for id, _ := range services {
+			if started[id] && !stopped[id] {
+				t.Fatalf("service %s: started but not stopped", id)
+			}
+			delete(started, id)
+			delete(stopped, id)
+		}
+	}
+}
+
+// Tests that even if a registered service fails to shut down cleanly, it does
+// not influece the rest of the shutdown invocations.
+func TestServiceTerminationGuarantee(t *testing.T) {
+	stack, err := New(testNodeConfig)
+	if err != nil {
+		t.Fatalf("failed to create protocol stack: %v", err)
+	}
+	// Register a batch of good services
+	services := map[string]InstrumentingWrapper{
+		"A": InstrumentedServiceMakerA,
+		"B": InstrumentedServiceMakerB,
+		"C": InstrumentedServiceMakerC,
+	}
+	started := make(map[string]bool)
+	stopped := make(map[string]bool)
+
+	for id, maker := range services {
+		id := id // Closure for the constructor
+		constructor := func(*ServiceContext) (Service, error) {
+			return &InstrumentedService{
+				startHook: func(*p2p.Server) { started[id] = true },
+				stopHook:  func() { stopped[id] = true },
+			}, nil
+		}
+		if err := stack.Register(maker(constructor)); err != nil {
+			t.Fatalf("service %s: registration failed: %v", id, err)
+		}
+	}
+	// Register a service that fails to shot down cleanly
+	failure := errors.New("fail")
+	failer := func(*ServiceContext) (Service, error) {
+		return &InstrumentedService{
+			stop: failure,
+		}, nil
+	}
+	if err := stack.Register(failer); err != nil {
+		t.Fatalf("failer registration failed: %v", err)
+	}
+	// Start the protocol stack, and ensure that a failing shut down terminates all
+	for i := 0; i < 100; i++ {
+		// Start the stack and make sure all is online
+		if err := stack.Start(); err != nil {
+			t.Fatalf("iter %d: failed to start protocol stack: %v", i, err)
+		}
+		for id, _ := range services {
+			if !started[id] {
+				t.Fatalf("iter %d, service %s: service not running", i, id)
+			}
+			if stopped[id] {
+				t.Fatalf("iter %d, service %s: service already stopped", i, id)
+			}
+		}
+		// Stop the stack, verify failure and check all terminations
+		err := stack.Stop()
+		if err, ok := err.(*StopError); !ok {
+			t.Fatalf("iter %d: termination failure mismatch: have %v, want StopError", i, err)
+		} else {
+			failer := reflect.TypeOf(&InstrumentedService{})
+			if err.Services[failer] != failure {
+				t.Fatalf("iter %d: failer termination failure mismatch: have %v, want %v", i, err.Services[failer], failure)
+			}
+			if len(err.Services) != 1 {
+				t.Fatalf("iter %d: failure count mismatch: have %d, want %d", i, len(err.Services), 1)
+			}
+		}
+		for id, _ := range services {
+			if !stopped[id] {
+				t.Fatalf("iter %d, service %s: service not terminated", i, id)
+			}
+			delete(started, id)
+			delete(stopped, id)
+		}
+	}
+}
+
+// TestServiceRetrieval tests that individual services can be retrieved.
+func TestServiceRetrieval(t *testing.T) {
+	// Create a simple stack and register two service types
+	stack, err := New(testNodeConfig)
+	if err != nil {
+		t.Fatalf("failed to create protocol stack: %v", err)
+	}
+	if err := stack.Register(NewNoopService); err != nil {
+		t.Fatalf("noop service registration failed: %v", err)
+	}
+	if err := stack.Register(NewInstrumentedService); err != nil {
+		t.Fatalf("instrumented service registration failed: %v", err)
+	}
+	// Make sure none of the services can be retrieved until started
+	var noopServ *NoopService
+	if err := stack.Service(&noopServ); err != ErrNodeStopped {
+		t.Fatalf("noop service retrieval mismatch: have %v, want %v", err, ErrNodeStopped)
+	}
+	var instServ *InstrumentedService
+	if err := stack.Service(&instServ); err != ErrNodeStopped {
+		t.Fatalf("instrumented service retrieval mismatch: have %v, want %v", err, ErrNodeStopped)
+	}
+	// Start the stack and ensure everything is retrievable now
+	if err := stack.Start(); err != nil {
+		t.Fatalf("failed to start stack: %v", err)
+	}
+	defer stack.Stop()
+
+	if err := stack.Service(&noopServ); err != nil {
+		t.Fatalf("noop service retrieval mismatch: have %v, want %v", err, nil)
+	}
+	if err := stack.Service(&instServ); err != nil {
+		t.Fatalf("instrumented service retrieval mismatch: have %v, want %v", err, nil)
+	}
+}
+
+// Tests that all protocols defined by individual services get launched.
+func TestProtocolGather(t *testing.T) {
+	stack, err := New(testNodeConfig)
+	if err != nil {
+		t.Fatalf("failed to create protocol stack: %v", err)
+	}
+	// Register a batch of services with some configured number of protocols
+	services := map[string]struct {
+		Count int
+		Maker InstrumentingWrapper
+	}{
+		"Zero Protocols":  {0, InstrumentedServiceMakerA},
+		"Single Protocol": {1, InstrumentedServiceMakerB},
+		"Many Protocols":  {25, InstrumentedServiceMakerC},
+	}
+	for id, config := range services {
+		protocols := make([]p2p.Protocol, config.Count)
+		for i := 0; i < len(protocols); i++ {
+			protocols[i].Name = id
+			protocols[i].Version = uint(i)
+		}
+		constructor := func(*ServiceContext) (Service, error) {
+			return &InstrumentedService{
+				protocols: protocols,
+			}, nil
+		}
+		if err := stack.Register(config.Maker(constructor)); err != nil {
+			t.Fatalf("service %s: registration failed: %v", id, err)
+		}
+	}
+	// Start the services and ensure all protocols start successfully
+	if err := stack.Start(); err != nil {
+		t.Fatalf("failed to start protocol stack: %v", err)
+	}
+	defer stack.Stop()
+
+	protocols := stack.Server().Protocols
+	if len(protocols) != 26 {
+		t.Fatalf("mismatching number of protocols launched: have %d, want %d", len(protocols), 26)
+	}
+	for id, config := range services {
+		for ver := 0; ver < config.Count; ver++ {
+			launched := false
+			for i := 0; i < len(protocols); i++ {
+				if protocols[i].Name == id && protocols[i].Version == uint(ver) {
+					launched = true
+					break
+				}
+			}
+			if !launched {
+				t.Errorf("configured protocol not launched: %s v%d", id, ver)
+			}
+		}
+	}
+}