Convert cluster test to a testable Go example.

examples/clusters/scripts.go → examples/basic/scripts.go

@@ -1,3 +1,3 @@
 //go:generate protoc --go_out=plugins=grpc:. messages/cluster.proto
 
-package main
+package basic

examples/clusters/main_test.go → examples/basic/setup.go

@@ -1,13 +1,11 @@
-package main
+package basic
 
 import (
-	"flag"
 	"fmt"
-	"testing"
 	"time"
 
 	"github.com/perlin-network/noise/crypto"
-	"github.com/perlin-network/noise/examples/clusters/messages"
+	"github.com/perlin-network/noise/examples/basic/messages"
 	"github.com/perlin-network/noise/grpc_utils"
 	"github.com/perlin-network/noise/network"
 	"github.com/perlin-network/noise/network/builders"
@@ -43,7 +41,8 @@ func (c *ClusterNode) PopMessage() *messages.ClusterTestMessage {
 
 var blockTimeout = 10 * time.Second
 
-func setupCluster(t *testing.T, nodes []*ClusterNode) error {
+// SetupCluster - Sets up a fully connected group of nodes in a cluster
+func SetupCluster(nodes []*ClusterNode) error {
 	peers := []string{}
 
 	for i := 0; i < len(nodes); i++ {
@@ -78,58 +77,9 @@ func setupCluster(t *testing.T, nodes []*ClusterNode) error {
 	for i := 0; i < len(nodes); i++ {
 		nodes[i].Net.Bootstrap(peers...)
 
-		// HACK: seems there's another race condition with Bootstrap
+		// TODO: seems there's another race condition with Bootstrap, use a sleep for now
 		time.Sleep(1 * time.Second)
 	}
 
 	return nil
 }
-
-func TestClusters(t *testing.T) {
-	flag.Parse()
-
-	host := "localhost"
-	cluster1StartPort := 3001
-	cluster1NumPorts := 3
-	nodes := []*ClusterNode{}
-
-	for i := 0; i < cluster1NumPorts; i++ {
-		node := &ClusterNode{}
-		node.Host = host
-		node.Port = cluster1StartPort + i
-
-		nodes = append(nodes, node)
-	}
-
-	if err := setupCluster(t, nodes); err != nil {
-		t.Fatal(err)
-	}
-
-	for i, node := range nodes {
-		if node.Net == nil {
-			t.Fatalf("Expected %d nodes, but node %d is missing a network", len(nodes), i)
-		}
-	}
-
-	// check if you can send a message from node 1 and will it be received only in node 2,3
-	{
-		testMessage := "message from node 0"
-		nodes[0].Net.Broadcast(&messages.ClusterTestMessage{Message: testMessage})
-
-		// HACK: TODO: replace sleep with something else
-		time.Sleep(1 * time.Second)
-
-		if result := nodes[0].PopMessage(); result != nil {
-			t.Errorf("Expected nothing in node 0, got %v", result)
-		}
-		for i := 1; i < len(nodes); i++ {
-			if result := nodes[i].PopMessage(); result == nil {
-				t.Errorf("Expected a message in node %d but it was blank", i)
-			} else {
-				if result.Message != testMessage {
-					t.Errorf("Expected message %s in node %d but got %v", testMessage, i, result)
-				}
-			}
-		}
-	}
-}

examples/basic/setup_test.go

@@ -0,0 +1,65 @@
+package basic
+
+import (
+	"flag"
+	"fmt"
+	"time"
+
+	"github.com/golang/glog"
+	"github.com/perlin-network/noise/examples/basic/messages"
+)
+
+func ExampleSetupClusters() {
+	// parse to flags to silence the glog library
+	flag.Parse()
+
+	host := "localhost"
+	cluster1StartPort := 5000
+	cluster1NumPorts := 3
+	nodes := []*ClusterNode{}
+
+	for i := 0; i < cluster1NumPorts; i++ {
+		node := &ClusterNode{}
+		node.Host = host
+		node.Port = cluster1StartPort + i
+
+		nodes = append(nodes, node)
+	}
+
+	if err := SetupCluster(nodes); err != nil {
+		fmt.Print(err)
+	}
+
+	for i, node := range nodes {
+		if node.Net == nil {
+			fmt.Printf("Expected %d nodes, but node %d is missing a network", len(nodes), i)
+		}
+	}
+
+	// check if you can send a message from node 1 and will it be received only in node 2,3
+	{
+		testMessage := "message from node 0"
+
+		// Broadcast is an asynchronous call to send a message to other nodes
+		nodes[0].Net.Broadcast(&messages.ClusterTestMessage{Message: testMessage})
+
+		// Simplificiation: message broadcasting is asynchronous, so need the messages to settle
+		time.Sleep(1 * time.Second)
+
+		if result := nodes[0].PopMessage(); result != nil {
+			glog.Errorf("Expected nothing in node 0, got %v", result)
+		}
+		for i := 1; i < len(nodes); i++ {
+			if result := nodes[i].PopMessage(); result == nil {
+				fmt.Printf("Expected a message in node %d but it was blank", i)
+			} else {
+				if result.Message != testMessage {
+					fmt.Printf("Expected message %s in node %d but got %v", testMessage, i, result)
+				}
+			}
+		}
+	}
+
+	fmt.Printf("Success")
+	// Output: Success
+}