Make Python compatability a flag

alert.go

@@ -51,16 +51,20 @@ func (alert *Alert) BuildTemplates() error {
 	if alert.commandTemplate == nil && alert.Command.Command != nil {
 		alert.commandTemplate = []*template.Template{}
 		for i, cmdPart := range alert.Command.Command {
-			cmdPart = legacy.Replace(cmdPart)
+			if PyCompat {
+				cmdPart = legacy.Replace(cmdPart)
+			}
 			alert.commandTemplate = append(alert.commandTemplate, template.Must(
 				template.New(alert.Name+string(i)).Parse(cmdPart),
 			))
 		}
 	} else if alert.commandShellTemplate == nil && alert.Command.ShellCommand != "" {
+		shellCmd := alert.Command.ShellCommand
+		if PyCompat {
+			shellCmd = legacy.Replace(shellCmd)
+		}
 		alert.commandShellTemplate = template.Must(
-			template.New(alert.Name).Parse(
-				legacy.Replace(alert.Command.ShellCommand),
-			),
+			template.New(alert.Name).Parse(shellCmd),
 		)
 	} else {
 		return fmt.Errorf("No template provided for alert %s", alert.Name)

alert_test.go

@@ -34,6 +34,7 @@ func TestAlertSend(t *testing.T) {
 		expectedOutput string
 		expectErr      bool
 		name           string
+		pyCompat       bool
 	}{
 		{
 			Alert{Command: CommandOrShell{Command: []string{"echo", "{{.MonitorName}}"}}},
@@ -41,6 +42,7 @@ func TestAlertSend(t *testing.T) {
 			"test\n",
 			false,
 			"Command with template",
+			false,
 		},
 		{
 			Alert{Command: CommandOrShell{ShellCommand: "echo {{.MonitorName}}"}},
@@ -48,6 +50,7 @@ func TestAlertSend(t *testing.T) {
 			"test\n",
 			false,
 			"Command shell with template",
+			false,
 		},
 		{
 			Alert{Command: CommandOrShell{Command: []string{"echo", "{{.Bad}}"}}},
@@ -55,6 +58,7 @@ func TestAlertSend(t *testing.T) {
 			"",
 			true,
 			"Command with bad template",
+			false,
 		},
 		{
 			Alert{Command: CommandOrShell{ShellCommand: "echo {{.Bad}}"}},
@@ -62,6 +66,7 @@ func TestAlertSend(t *testing.T) {
 			"",
 			true,
 			"Command shell with bad template",
+			false,
 		},
 		{
 			Alert{Command: CommandOrShell{ShellCommand: "echo {alert_message}"}},
@@ -69,11 +74,14 @@ func TestAlertSend(t *testing.T) {
 			"test check has failed 1 times\n",
 			false,
 			"Command shell with legacy template",
+			true,
 		},
 	}
 
 	for _, c := range cases {
 		log.Printf("Testing case %s", c.name)
+		// Set PyCompat to value of compat flag
+		PyCompat = c.pyCompat
 		c.alert.BuildTemplates()
 		output, err := c.alert.Send(c.notice)
 		hasErr := (err != nil)
@@ -85,6 +93,8 @@ func TestAlertSend(t *testing.T) {
 			t.Errorf("Send(%v err), expected=%v actual=%v", c.name, "Err", err)
 			log.Printf("Case failed: %s", c.name)
 		}
+		// Set PyCompat back to default value
+		PyCompat = false
 		log.Println("-----")
 	}
 }

config.go

@@ -118,14 +118,15 @@ func LoadConfig(filePath string) (config Config, err error) {
 		log.Printf("DEBUG: Config values:\n%v\n", config)
 	}
 
-	// Intialize alerts list if not present
-	if config.Alerts == nil {
-		config.Alerts = map[string]*Alert{}
-	}
-
 	// Add log alert if not present
-	if _, ok := config.Alerts["log"]; !ok {
-		config.Alerts["log"] = NewLogAlert()
+	if PyCompat {
+		// Intialize alerts list if not present
+		if config.Alerts == nil {
+			config.Alerts = map[string]*Alert{}
+		}
+		if _, ok := config.Alerts["log"]; !ok {
+			config.Alerts["log"] = NewLogAlert()
+		}
 	}
 
 	if !config.IsValid() {

config_test.go

@@ -10,23 +10,29 @@ func TestLoadConfig(t *testing.T) {
 		configPath string
 		expectErr  bool
 		name       string
+		pyCompat   bool
 	}{
-		{"./test/valid-config.yml", false, "Valid config file"},
-		{"./test/valid-default-log-alert.yml", false, "Valid config file with default log alert"},
-		{"./test/does-not-exist", true, "Invalid config path"},
-		{"./test/invalid-config-type.yml", true, "Invalid config type for key"},
-		{"./test/invalid-config-missing-alerts.yml", true, "Invalid config missing alerts"},
-		{"./test/invalid-config-unknown-alert.yml", true, "Invalid config unknown alert"},
+		{"./test/valid-config.yml", false, "Valid config file", false},
+		{"./test/valid-default-log-alert.yml", false, "Valid config file with default log alert PyCompat", true},
+		{"./test/valid-default-log-alert.yml", true, "Invalid config file no log alert", false},
+		{"./test/does-not-exist", true, "Invalid config path", false},
+		{"./test/invalid-config-type.yml", true, "Invalid config type for key", false},
+		{"./test/invalid-config-missing-alerts.yml", true, "Invalid config missing alerts", false},
+		{"./test/invalid-config-unknown-alert.yml", true, "Invalid config unknown alert", false},
 	}
 
 	for _, c := range cases {
 		log.Printf("Testing case %s", c.name)
+		// Set PyCompat based on compatibility mode
+		PyCompat = c.pyCompat
 		_, err := LoadConfig(c.configPath)
 		hasErr := (err != nil)
 		if hasErr != c.expectErr {
 			t.Errorf("LoadConfig(%v), expected_error=%v actual=%v", c.name, c.expectErr, err)
 			log.Printf("Case failed: %s", c.name)
 		}
+		// Set PyCompat to default value
+		PyCompat = false
 		log.Println("-----")
 	}
 }

main.go

@@ -18,6 +18,9 @@ var (
 	// Metrics contains all active metrics
 	Metrics = NewMetrics()
 
+	// PyCompat enables support for legacy Python templates
+	PyCompat = false
+
 	// version of minitor being run
 	version = "dev"
 )
@@ -83,6 +86,7 @@ func main() {
 	// Get debug flag
 	flag.BoolVar(&LogDebug, "debug", false, "Enables debug logs (default: false)")
 	flag.BoolVar(&ExportMetrics, "metrics", false, "Enables prometheus metrics exporting (default: false)")
+	flag.BoolVar(&PyCompat, "py-compat", false, "Enables support for legacy Python Minitor config. Will eventually be removed. (default: false)")
 	var showVersion = flag.Bool("version", false, "Display the version of minitor and exit")
 	var configPath = flag.String("config", "config.yml", "Alternate configuration path (default: config.yml)")
 	flag.Parse()