swarm: network simulation for swarm tests (#769)

* cmd/swarm: minor cli flag text adjustments

* cmd/swarm, swarm/storage, swarm: fix  mingw on windows test issues

* cmd/swarm: support for smoke tests on the production swarm cluster

* cmd/swarm/swarm-smoke: simplify cluster logic as per suggestion

* changed colour of landing page

* landing page reacts to enter keypress

* swarm/api/http: sticky footer for swarm landing page using flex

* swarm/api/http: sticky footer for error pages and fix for multiple choices

* swarm: propagate ctx to internal apis (#754)

* swarm/simnet: add basic node/service functions

* swarm/netsim: add buckets for global state and kademlia health check

* swarm/netsim: Use sync.Map as bucket and provide cleanup function for...

* swarm, swarm/netsim: adjust SwarmNetworkTest

* swarm/netsim: fix tests

* swarm: added visualization option to sim net redesign

* swarm/netsim: support multiple services per node

* swarm/netsim: remove redundant return statement

* swarm/netsim: add comments

* swarm: shutdown HTTP in Simulation.Close

* swarm: sim HTTP server timeout

* swarm/netsim: add more simulation methods and peer events examples

* swarm/netsim: add WaitKademlia example

* swarm/netsim: fix comments

* swarm/netsim: terminate peer events goroutines on simulation done

* swarm, swarm/netsim: naming updates

* swarm/netsim: return not healthy kademlias on WaitTillHealthy

* swarm: fix WaitTillHealthy call in testSwarmNetwork

* swarm/netsim: allow bucket to have any type for a key

* swarm: Added snapshots to new netsim

* swarm/netsim: add more tests for bucket

* swarm/netsim: move http related things into separate files

* swarm/netsim: add AddNodeWithService option

* swarm/netsim: add more tests and Start* methods

* swarm/netsim: add peer events and kademlia tests

* swarm/netsim: fix some tests flakiness

* swarm/netsim: improve random nodes selection, fix TestStartStop* tests

* swarm/netsim: remove time measurement from TestClose to avoid flakiness

* swarm/netsim: builder pattern for netsim HTTP server (#773)

* swarm/netsim: add connect related tests

* swarm/netsim: add comment for TestPeerEvents

* swarm: rename netsim package to network/simulation

1 files changed, 462 insertions, 0 deletions

diff --git a/swarm/network/simulation/node_test.go b/swarm/network/simulation/node_test.go
new file mode 100644
index 000000000..94f0b4fac
--- /dev/null
+++ b/swarm/network/simulation/node_test.go
@@ -0,0 +1,462 @@
+// 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 simulation
+
+import (
+	"context"
+	"fmt"
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/ethereum/go-ethereum/log"
+	"github.com/ethereum/go-ethereum/node"
+	"github.com/ethereum/go-ethereum/p2p/discover"
+	"github.com/ethereum/go-ethereum/p2p/simulations/adapters"
+	"github.com/ethereum/go-ethereum/swarm/network"
+)
+
+func TestUpDownNodeIDs(t *testing.T) {
+	sim := New(noopServiceFuncMap)
+	defer sim.Close()
+
+	ids, err := sim.AddNodes(10)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	gotIDs := sim.NodeIDs()
+
+	if !equalNodeIDs(ids, gotIDs) {
+		t.Error("returned nodes are not equal to added ones")
+	}
+
+	stoppedIDs, err := sim.StopRandomNodes(3)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	gotIDs = sim.UpNodeIDs()
+
+	for _, id := range gotIDs {
+		if !sim.Net.GetNode(id).Up {
+			t.Errorf("node %s should not be down", id)
+		}
+	}
+
+	if !equalNodeIDs(ids, append(gotIDs, stoppedIDs...)) {
+		t.Error("returned nodes are not equal to added ones")
+	}
+
+	gotIDs = sim.DownNodeIDs()
+
+	for _, id := range gotIDs {
+		if sim.Net.GetNode(id).Up {
+			t.Errorf("node %s should not be up", id)
+		}
+	}
+
+	if !equalNodeIDs(stoppedIDs, gotIDs) {
+		t.Error("returned nodes are not equal to the stopped ones")
+	}
+}
+
+func equalNodeIDs(one, other []discover.NodeID) bool {
+	if len(one) != len(other) {
+		return false
+	}
+	var count int
+	for _, a := range one {
+		var found bool
+		for _, b := range other {
+			if a == b {
+				found = true
+				break
+			}
+		}
+		if found {
+			count++
+		} else {
+			return false
+		}
+	}
+	return count == len(one)
+}
+
+func TestAddNode(t *testing.T) {
+	sim := New(noopServiceFuncMap)
+	defer sim.Close()
+
+	id, err := sim.AddNode()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	n := sim.Net.GetNode(id)
+	if n == nil {
+		t.Fatal("node not found")
+	}
+
+	if !n.Up {
+		t.Error("node not started")
+	}
+}
+
+func TestAddNodeWithMsgEvents(t *testing.T) {
+	sim := New(noopServiceFuncMap)
+	defer sim.Close()
+
+	id, err := sim.AddNode(AddNodeWithMsgEvents(true))
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if !sim.Net.GetNode(id).Config.EnableMsgEvents {
+		t.Error("EnableMsgEvents is false")
+	}
+
+	id, err = sim.AddNode(AddNodeWithMsgEvents(false))
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if sim.Net.GetNode(id).Config.EnableMsgEvents {
+		t.Error("EnableMsgEvents is true")
+	}
+}
+
+func TestAddNodeWithService(t *testing.T) {
+	sim := New(map[string]ServiceFunc{
+		"noop1": noopServiceFunc,
+		"noop2": noopServiceFunc,
+	})
+	defer sim.Close()
+
+	id, err := sim.AddNode(AddNodeWithService("noop1"))
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	n := sim.Net.GetNode(id).Node.(*adapters.SimNode)
+	if n.Service("noop1") == nil {
+		t.Error("service noop1 not found on node")
+	}
+	if n.Service("noop2") != nil {
+		t.Error("service noop2 should not be found on node")
+	}
+}
+
+func TestAddNodes(t *testing.T) {
+	sim := New(noopServiceFuncMap)
+	defer sim.Close()
+
+	nodesCount := 12
+
+	ids, err := sim.AddNodes(nodesCount)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	count := len(ids)
+	if count != nodesCount {
+		t.Errorf("expected %v nodes, got %v", nodesCount, count)
+	}
+
+	count = len(sim.Net.GetNodes())
+	if count != nodesCount {
+		t.Errorf("expected %v nodes, got %v", nodesCount, count)
+	}
+}
+
+func TestAddNodesAndConnectFull(t *testing.T) {
+	sim := New(noopServiceFuncMap)
+	defer sim.Close()
+
+	n := 12
+
+	ids, err := sim.AddNodesAndConnectFull(n)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	testFull(t, sim, ids)
+}
+
+func TestAddNodesAndConnectChain(t *testing.T) {
+	sim := New(noopServiceFuncMap)
+	defer sim.Close()
+
+	_, err := sim.AddNodesAndConnectChain(12)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// add another set of nodes to test
+	// if two chains are connected
+	_, err = sim.AddNodesAndConnectChain(7)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	testChain(t, sim, sim.UpNodeIDs())
+}
+
+func TestAddNodesAndConnectRing(t *testing.T) {
+	sim := New(noopServiceFuncMap)
+	defer sim.Close()
+
+	ids, err := sim.AddNodesAndConnectRing(12)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	testRing(t, sim, ids)
+}
+
+func TestAddNodesAndConnectStar(t *testing.T) {
+	sim := New(noopServiceFuncMap)
+	defer sim.Close()
+
+	ids, err := sim.AddNodesAndConnectStar(12)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	testStar(t, sim, ids, 0)
+}
+
+//To test that uploading a snapshot works
+func TestUploadSnapshot(t *testing.T) {
+	log.Debug("Creating simulation")
+	s := New(map[string]ServiceFunc{
+		"bzz": func(ctx *adapters.ServiceContext, b *sync.Map) (node.Service, func(), error) {
+			addr := network.NewAddrFromNodeID(ctx.Config.ID)
+			hp := network.NewHiveParams()
+			hp.Discovery = false
+			config := &network.BzzConfig{
+				OverlayAddr:  addr.Over(),
+				UnderlayAddr: addr.Under(),
+				HiveParams:   hp,
+			}
+			kad := network.NewKademlia(addr.Over(), network.NewKadParams())
+			return network.NewBzz(config, kad, nil, nil, nil), nil, nil
+		},
+	})
+	defer s.Close()
+
+	nodeCount := 16
+	log.Debug("Uploading snapshot")
+	err := s.UploadSnapshot(fmt.Sprintf("../stream/testing/snapshot_%d.json", nodeCount))
+	if err != nil {
+		t.Fatalf("Error uploading snapshot to simulation network: %v", err)
+	}
+
+	ctx := context.Background()
+	log.Debug("Starting simulation...")
+	s.Run(ctx, func(ctx context.Context, sim *Simulation) error {
+		log.Debug("Checking")
+		nodes := sim.UpNodeIDs()
+		if len(nodes) != nodeCount {
+			t.Fatal("Simulation network node number doesn't match snapshot node number")
+		}
+		return nil
+	})
+	log.Debug("Done.")
+}
+
+func TestPivotNode(t *testing.T) {
+	sim := New(noopServiceFuncMap)
+	defer sim.Close()
+
+	id, err := sim.AddNode()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	id2, err := sim.AddNode()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if sim.PivotNodeID() != nil {
+		t.Error("expected no pivot node")
+	}
+
+	sim.SetPivotNode(id)
+
+	pid := sim.PivotNodeID()
+
+	if pid == nil {
+		t.Error("pivot node not set")
+	} else if *pid != id {
+		t.Errorf("expected pivot node %s, got %s", id, *pid)
+	}
+
+	sim.SetPivotNode(id2)
+
+	pid = sim.PivotNodeID()
+
+	if pid == nil {
+		t.Error("pivot node not set")
+	} else if *pid != id2 {
+		t.Errorf("expected pivot node %s, got %s", id2, *pid)
+	}
+}
+
+func TestStartStopNode(t *testing.T) {
+	sim := New(noopServiceFuncMap)
+	defer sim.Close()
+
+	id, err := sim.AddNode()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	n := sim.Net.GetNode(id)
+	if n == nil {
+		t.Fatal("node not found")
+	}
+	if !n.Up {
+		t.Error("node not started")
+	}
+
+	err = sim.StopNode(id)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if n.Up {
+		t.Error("node not stopped")
+	}
+
+	// Sleep here to ensure that Network.watchPeerEvents defer function
+	// has set the `node.Up = false` before we start the node again.
+	// p2p/simulations/network.go:215
+	//
+	// The same node is stopped and started again, and upon start
+	// watchPeerEvents is started in a goroutine. If the node is stopped
+	// and then very quickly started, that goroutine may be scheduled later
+	// then start and force `node.Up = false` in its defer function.
+	// This will make this test unreliable.
+	time.Sleep(time.Second)
+
+	err = sim.StartNode(id)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !n.Up {
+		t.Error("node not started")
+	}
+}
+
+func TestStartStopRandomNode(t *testing.T) {
+	sim := New(noopServiceFuncMap)
+	defer sim.Close()
+
+	_, err := sim.AddNodes(3)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	id, err := sim.StopRandomNode()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	n := sim.Net.GetNode(id)
+	if n == nil {
+		t.Fatal("node not found")
+	}
+	if n.Up {
+		t.Error("node not stopped")
+	}
+
+	id2, err := sim.StopRandomNode()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// Sleep here to ensure that Network.watchPeerEvents defer function
+	// has set the `node.Up = false` before we start the node again.
+	// p2p/simulations/network.go:215
+	//
+	// The same node is stopped and started again, and upon start
+	// watchPeerEvents is started in a goroutine. If the node is stopped
+	// and then very quickly started, that goroutine may be scheduled later
+	// then start and force `node.Up = false` in its defer function.
+	// This will make this test unreliable.
+	time.Sleep(time.Second)
+
+	idStarted, err := sim.StartRandomNode()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if idStarted != id && idStarted != id2 {
+		t.Error("unexpected started node ID")
+	}
+}
+
+func TestStartStopRandomNodes(t *testing.T) {
+	sim := New(noopServiceFuncMap)
+	defer sim.Close()
+
+	_, err := sim.AddNodes(10)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	ids, err := sim.StopRandomNodes(3)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	for _, id := range ids {
+		n := sim.Net.GetNode(id)
+		if n == nil {
+			t.Fatal("node not found")
+		}
+		if n.Up {
+			t.Error("node not stopped")
+		}
+	}
+
+	// Sleep here to ensure that Network.watchPeerEvents defer function
+	// has set the `node.Up = false` before we start the node again.
+	// p2p/simulations/network.go:215
+	//
+	// The same node is stopped and started again, and upon start
+	// watchPeerEvents is started in a goroutine. If the node is stopped
+	// and then very quickly started, that goroutine may be scheduled later
+	// then start and force `node.Up = false` in its defer function.
+	// This will make this test unreliable.
+	time.Sleep(time.Second)
+
+	ids, err = sim.StartRandomNodes(2)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	for _, id := range ids {
+		n := sim.Net.GetNode(id)
+		if n == nil {
+			t.Fatal("node not found")
+		}
+		if !n.Up {
+			t.Error("node not started")
+		}
+	}
+}