p2p/simulations, swarm/network: Custom services in snapshot (#17991)

* p2p/simulations: Add custom services to simnodes + remove sim down conn objs

* p2p/simulation, swarm/network: Add selective services to discovery sim

* p2p/simulations, swarm/network: Remove useless comments

* p2p/simulations, swarm/network: Clean up mess from rebase

* p2p/simulation: Add sleep to prevent connect flakiness in http test

* p2p/simulations: added concurrent goroutines to prevent sleeps on simulation connect/disconnect

* p2p/simulations, swarm/network/simulations: address pr comments

* reinstated dummy service

* fixed http snapshot test

p2p/simulations/http_test.go

@@ -18,6 +18,7 @@ package simulations
 
 import (
 	"context"
+	"flag"
 	"fmt"
 	"math/rand"
 	"net/http/httptest"
@@ -28,13 +29,26 @@ import (
 	"time"
 
 	"github.com/ethereum/go-ethereum/event"
+	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/node"
 	"github.com/ethereum/go-ethereum/p2p"
 	"github.com/ethereum/go-ethereum/p2p/enode"
 	"github.com/ethereum/go-ethereum/p2p/simulations/adapters"
 	"github.com/ethereum/go-ethereum/rpc"
+	colorable "github.com/mattn/go-colorable"
 )
 
+var (
+	loglevel = flag.Int("loglevel", 2, "verbosity of logs")
+)
+
+func init() {
+	flag.Parse()
+
+	log.PrintOrigins(true)
+	log.Root().SetHandler(log.LvlFilterHandler(log.Lvl(*loglevel), log.StreamHandler(colorable.NewColorableStderr(), log.TerminalFormat(true))))
+}
+
 // testService implements the node.Service interface and provides protocols
 // and APIs which are useful for testing nodes in a simulation network
 type testService struct {
@@ -584,9 +598,26 @@ func TestHTTPNodeRPC(t *testing.T) {
 // TestHTTPSnapshot tests creating and loading network snapshots
 func TestHTTPSnapshot(t *testing.T) {
 	// start the server
-	_, s := testHTTPServer(t)
+	network, s := testHTTPServer(t)
 	defer s.Close()
 
+	var eventsDone = make(chan struct{})
+	count := 1
+	eventsDoneChan := make(chan *Event)
+	eventSub := network.Events().Subscribe(eventsDoneChan)
+	go func() {
+		defer eventSub.Unsubscribe()
+		for event := range eventsDoneChan {
+			if event.Type == EventTypeConn && !event.Control {
+				count--
+				if count == 0 {
+					eventsDone <- struct{}{}
+					return
+				}
+			}
+		}
+	}()
+
 	// create a two-node network
 	client := NewClient(s.URL)
 	nodeCount := 2
@@ -620,7 +651,7 @@ func TestHTTPSnapshot(t *testing.T) {
 		}
 		states[i] = state
 	}
-
+	<-eventsDone
 	// create a snapshot
 	snap, err := client.CreateSnapshot()
 	if err != nil {
@@ -634,9 +665,23 @@ func TestHTTPSnapshot(t *testing.T) {
 	}
 
 	// create another network
-	_, s = testHTTPServer(t)
+	network2, s := testHTTPServer(t)
 	defer s.Close()
 	client = NewClient(s.URL)
+	count = 1
+	eventSub = network2.Events().Subscribe(eventsDoneChan)
+	go func() {
+		defer eventSub.Unsubscribe()
+		for event := range eventsDoneChan {
+			if event.Type == EventTypeConn && !event.Control {
+				count--
+				if count == 0 {
+					eventsDone <- struct{}{}
+					return
+				}
+			}
+		}
+	}()
 
 	// subscribe to events so we can check them later
 	events := make(chan *Event, 100)
@@ -651,6 +696,7 @@ func TestHTTPSnapshot(t *testing.T) {
 	if err := client.LoadSnapshot(snap); err != nil {
 		t.Fatalf("error loading snapshot: %s", err)
 	}
+	<-eventsDone
 
 	// check the nodes and connection exists
 	net, err := client.GetNetwork()
@@ -676,6 +722,9 @@ func TestHTTPSnapshot(t *testing.T) {
 	if conn.Other.String() != nodes[1].ID {
 		t.Fatalf("expected connection to have other=%q, got other=%q", nodes[1].ID, conn.Other)
 	}
+	if !conn.Up {
+		t.Fatal("should be up")
+	}
 
 	// check the node states were restored
 	for i, node := range nodes {