agent: scada client and HTTP server are tracked separately

command/agent/command.go

@@ -48,6 +48,7 @@ type Command struct {
 	httpServers       []*HTTPServer
 	dnsServer         *DNSServer
 	scadaProvider     *scada.Provider
+	scadaHttp         *HTTPServer
 }
 
 // readConfig is responsible for setup of our configuration using
@@ -357,8 +358,8 @@ func (c *Command) setupAgent(config *Config, logOutput io.Writer, logWriter *log
 		scadaList = list
 	}
 
-	if config.Ports.HTTP > 0 || config.Ports.HTTPS > 0 || scadaList != nil {
-		servers, err := NewHTTPServers(agent, config, scadaList, logOutput)
+	if config.Ports.HTTP > 0 || config.Ports.HTTPS > 0 {
+		servers, err := NewHTTPServers(agent, config, logOutput)
 		if err != nil {
 			agent.Shutdown()
 			c.Ui.Error(fmt.Sprintf("Error starting http servers: %s", err))
@@ -367,6 +368,10 @@ func (c *Command) setupAgent(config *Config, logOutput io.Writer, logWriter *log
 		c.httpServers = servers
 	}
 
+	if scadaList != nil {
+		c.scadaHttp = newScadaHttp(agent, scadaList)
+	}
+
 	if config.Ports.DNS > 0 {
 		dnsAddr, err := config.ClientListener(config.Addresses.DNS, config.Ports.DNS)
 		if err != nil {
@@ -684,9 +689,16 @@ AFTER_MIGRATE:
 	for _, server := range c.httpServers {
 		defer server.Shutdown()
 	}
-	if c.scadaProvider != nil {
-		defer c.scadaProvider.Shutdown()
-	}
+
+	// Check and shut down the SCADA listeners at the end
+	defer func() {
+		if c.scadaHttp != nil {
+			c.scadaHttp.Shutdown()
+		}
+		if c.scadaProvider != nil {
+			c.scadaProvider.Shutdown()
+		}
+	}()
 
 	// Join startup nodes if specified
 	if err := c.startupJoin(config); err != nil {
@@ -904,6 +916,24 @@ func (c *Command) handleReload(config *Config) *Config {
 		}(wp)
 	}
 
+	// Reload the SCADA client
+	if c.scadaProvider != nil {
+		// Shut down the existing SCADA listeners
+		c.scadaProvider.Shutdown()
+		if c.scadaHttp != nil {
+			c.scadaHttp.Shutdown()
+		}
+
+		// Create the new provider and listener
+		provider, list, err := NewProvider(newConf, c.logOutput)
+		if err != nil {
+			c.Ui.Error(fmt.Sprintf("Failed reloading SCADA client: %s", err))
+			return nil
+		}
+		c.scadaProvider = provider
+		c.scadaHttp = newScadaHttp(c.agent, list)
+	}
+
 	return newConf
 }
 

command/agent/http.go

@@ -41,7 +41,7 @@ type HTTPServer struct {
 
 // NewHTTPServers starts new HTTP servers to provide an interface to
 // the agent.
-func NewHTTPServers(agent *Agent, config *Config, scada net.Listener, logOutput io.Writer) ([]*HTTPServer, error) {
+func NewHTTPServers(agent *Agent, config *Config, logOutput io.Writer) ([]*HTTPServer, error) {
 	var servers []*HTTPServer
 
 	if config.Ports.HTTPS > 0 {
@@ -142,29 +142,28 @@ func NewHTTPServers(agent *Agent, config *Config, scada net.Listener, logOutput
 		servers = append(servers, srv)
 	}
 
-	if scada != nil {
-		// Create the mux
-		mux := http.NewServeMux()
-
-		// Create the server
-		srv := &HTTPServer{
-			agent:    agent,
-			mux:      mux,
-			listener: scada,
-			logger:   log.New(logOutput, "", log.LstdFlags),
-			uiDir:    config.UiDir,
-			addr:     scadaHTTPAddr,
-		}
-		srv.registerHandlers(false) // Never allow debug for SCADA
-
-		// Start the server
-		go http.Serve(scada, mux)
-		servers = append(servers, srv)
-	}
-
 	return servers, nil
 }
 
+func newScadaHttp(agent *Agent, list net.Listener) *HTTPServer {
+	// Create the mux
+	mux := http.NewServeMux()
+
+	// Create the server
+	srv := &HTTPServer{
+		agent:    agent,
+		mux:      mux,
+		listener: list,
+		logger:   agent.logger,
+		addr:     scadaHTTPAddr,
+	}
+	srv.registerHandlers(false) // Never allow debug for SCADA
+
+	// Start the server
+	go http.Serve(list, mux)
+	return srv
+}
+
 // tcpKeepAliveListener sets TCP keep-alive timeouts on accepted
 // connections. It's used by NewHttpServer so
 // dead TCP connections eventually go away.

command/agent/http_test.go

@@ -38,7 +38,7 @@ func makeHTTPServerWithConfig(t *testing.T, cb func(c *Config)) (string, *HTTPSe
 		t.Fatalf("err: %v", err)
 	}
 	conf.UiDir = uiDir
-	servers, err := NewHTTPServers(agent, conf, nil, agent.logOutput)
+	servers, err := NewHTTPServers(agent, conf, agent.logOutput)
 	if err != nil {
 		t.Fatalf("err: %v", err)
 	}
@@ -148,7 +148,7 @@ func TestHTTPServer_UnixSocket_FileExists(t *testing.T) {
 	defer os.RemoveAll(dir)
 
 	// Try to start the server with the same path anyways.
-	if _, err := NewHTTPServers(agent, conf, nil, agent.logOutput); err != nil {
+	if _, err := NewHTTPServers(agent, conf, agent.logOutput); err != nil {
 		t.Fatalf("err: %s", err)
 	}
 

command/util_test.go

@@ -70,7 +70,7 @@ func testAgentWithConfig(t *testing.T, cb func(c *agent.Config)) *agentWrapper {
 
 	conf.Addresses.HTTP = "127.0.0.1"
 	httpAddr := fmt.Sprintf("127.0.0.1:%d", conf.Ports.HTTP)
-	http, err := agent.NewHTTPServers(a, conf, nil, os.Stderr)
+	http, err := agent.NewHTTPServers(a, conf, os.Stderr)
 	if err != nil {
 		os.RemoveAll(dir)
 		t.Fatalf(fmt.Sprintf("err: %v", err))