From 5d65f3bbd4dac7d2c0756ab3c653116e32a3062f Mon Sep 17 00:00:00 2001
From: Erik Brakkee <erik@brakkee.org>
Date: Wed, 21 Aug 2024 23:48:37 +0200
Subject: [PATCH] protocol version test implemented between agent and server
 (and found that it did not work)

---
 pkg/comms/agentserver.go      | 22 +++++++++++----------
 pkg/comms/agentserver_test.go | 36 ++++++++++++++++++++++++++++++++---
 pkg/comms/events.go           |  7 ++++++-
 3 files changed, 51 insertions(+), 14 deletions(-)

diff --git a/pkg/comms/agentserver.go b/pkg/comms/agentserver.go
index 0437e82..076fb4d 100644
--- a/pkg/comms/agentserver.go
+++ b/pkg/comms/agentserver.go
@@ -146,7 +146,9 @@ func ListenForServerEvents(channel CommChannel) {
 func AgentInitialization(conn io.ReadWriter, agentInto EnvironmentInfo) (ServerInfo, error) {
 	channel := NewGOBChannel(conn)
 	err := CheckProtocolVersion(Agent, channel)
-
+	if err != nil {
+		return ServerInfo{}, err
+	}
 	err = SendWithTimeout(channel, agentInto)
 	if err != nil {
 		return ServerInfo{}, nil
@@ -155,16 +157,16 @@ func AgentInitialization(conn io.ReadWriter, agentInto EnvironmentInfo) (ServerI
 	if err != nil {
 		return ServerInfo{}, nil
 	}
-	// TODO remove logging
 	log.Println("Agent configuration received from server")
-
 	return serverInfo, err
 }
 
 func ServerInitialization(conn io.ReadWriter, serverInfo ServerInfo) (EnvironmentInfo, error) {
 	channel := NewGOBChannel(conn)
 	err := CheckProtocolVersion(ConvergeServer, channel)
-
+	if err != nil {
+		return EnvironmentInfo{}, err
+	}
 	agentInfo, err := ReceiveWithTimeout[EnvironmentInfo](channel)
 	if err != nil {
 		return EnvironmentInfo{}, err
@@ -187,7 +189,7 @@ func ServerInitialization(conn io.ReadWriter, serverInfo ServerInfo) (Environmen
 func CheckProtocolVersion(role Role, channel GOBChannel) error {
 	switch role {
 	case Agent:
-		err := SendWithTimeout(channel, ProtocolVersion{Version: PROTOCOL_VERSION})
+		err := SendWithTimeout(channel, ProtocolVersion{Version: agentProtocolVersion})
 		if err != nil {
 			return err
 		}
@@ -195,9 +197,9 @@ func CheckProtocolVersion(role Role, channel GOBChannel) error {
 		if err != nil {
 			return err
 		}
-		if version.Version != PROTOCOL_VERSION {
+		if version.Version != agentProtocolVersion {
 			return fmt.Errorf("Protocol version mismatch: agent %d, converge server %d",
-				PROTOCOL_VERSION, version.Version)
+				agentProtocolVersion, version.Version)
 		}
 		return nil
 	case ConvergeServer:
@@ -205,13 +207,13 @@ func CheckProtocolVersion(role Role, channel GOBChannel) error {
 		if err != nil {
 			return err
 		}
-		err = SendWithTimeout(channel, ProtocolVersion{Version: PROTOCOL_VERSION})
+		err = SendWithTimeout(channel, ProtocolVersion{Version: serverProtocolVersion})
 		if err != nil {
 			return err
 		}
-		if version.Version != PROTOCOL_VERSION {
+		if version.Version != serverProtocolVersion {
 			return fmt.Errorf("Protocol version mismatch: agent %d, converge server %d",
-				PROTOCOL_VERSION, version.Version)
+				serverProtocolVersion, version.Version)
 		}
 		return nil
 	default:
diff --git a/pkg/comms/agentserver_test.go b/pkg/comms/agentserver_test.go
index d37622c..4214f2a 100644
--- a/pkg/comms/agentserver_test.go
+++ b/pkg/comms/agentserver_test.go
@@ -8,6 +8,7 @@ import (
 	"log"
 	"math/rand"
 	"net/http"
+	"strings"
 	"testing"
 	"time"
 )
@@ -48,6 +49,8 @@ func (s *AgentServerTestSuite) SetupTest() {
 }
 
 func (suite *AgentServerTestSuite) TearDownTest() {
+	agentProtocolVersion = PROTOCOL_VERSION
+	serverProtocolVersion = PROTOCOL_VERSION
 }
 
 func TestAgentServerTestSuite(t *testing.T) {
@@ -163,6 +166,32 @@ func (s *AgentServerTestSuite) Test_Initialization() {
 		})
 }
 
+func (s *AgentServerTestSuite) Test_InitializationProtocolVersionMismatch() {
+	serverProtocolVersion++
+	testsupport.RunAndWait(
+		&s.Suite,
+		func() any {
+			serverInfo, err := AgentInitialization(s.agentConnection,
+				NewEnvironmentInfo("myshell"))
+			s.NotNil(err)
+			s.True(strings.Contains(strings.ToLower(err.Error()), "protocol"))
+			s.Equal(ServerInfo{}, serverInfo)
+			return nil
+		},
+		func() any {
+			serverInfo := ServerInfo{TestId: 1000}
+			environmentInfo, err := ServerInitialization(s.serverConnection, serverInfo)
+			s.NotNil(err)
+			s.True(strings.Contains(strings.ToLower(err.Error()), "protocol"))
+			s.Equal(EnvironmentInfo{}, environmentInfo)
+			return nil
+		})
+}
+
+// TODO:
+// Test for protocolversion mismatch: verify error is returned. Use sentinel error
+// Tests when connection is close from agent and from server: verify error is returned
+
 func (s *AgentServerTestSuite) Test_ListenForAgentEvents() {
 
 	agentEvents := []any{
@@ -217,6 +246,7 @@ func (s *AgentServerTestSuite) Test_ListenForAgentEvents() {
 		})
 }
 
-func (s *AgentServerTestSuite) Test_LIstenForServerEvents() {
-
-}
+// This is currently a Noop. No need to test it.
+//func (s *AgentServerTestSuite) Test_LIstenForServerEvents() {
+//
+//}
diff --git a/pkg/comms/events.go b/pkg/comms/events.go
index 41e5beb..0a12365 100644
--- a/pkg/comms/events.go
+++ b/pkg/comms/events.go
@@ -8,7 +8,12 @@ import (
 	"time"
 )
 
-const PROTOCOL_VERSION = 4
+const PROTOCOL_VERSION = 5
+
+// for testing protocol version mismatch we define a separate protocol version
+// for the agent and server
+var agentProtocolVersion = PROTOCOL_VERSION
+var serverProtocolVersion = PROTOCOL_VERSION
 
 func init() {
 	RegisterEventsWithGob()