fix: don't panic when no template is defined

config.yaml

@@ -163,23 +163,23 @@ disks:
     last_active: 50m
     standby_after: 1h
 
-templates:
-  zabbix:
-    source: "zabbix_template.go.txt"
+# templates:
+#   zabbix:
+#     source: "zabbix_template.go.txt"
 
-tasks:
-  zabbix_sender:
-    command: "zabbix_sender -z 127.0.0.1 -s \"Zabbix server\" -i -"
-    timeout: 5s
-    stdin:
-      template: zabbix
+# tasks:
+#   zabbix_sender:
+#     command: "zabbix_sender -z 127.0.0.1 -s \"Zabbix server\" -i -"
+#     timeout: 5s
+#     stdin:
+#       template: zabbix
 
-schedule:
-  zabbix:
-    task: zabbix_sender
-    when:
-    - startup
-    - every 5m
+# schedule:
+#   zabbix:
+#     task: zabbix_sender
+#     when:
+#     - startup
+#     - every 5m
 
 telemetry:
   prometheus:

lib/global.go

@@ -84,10 +84,12 @@ func NewGlobal(config cfg.Config) (*Global, error) {
 		templates = append(templates, source)
 	}
 
-	// Now load the templates
-	global.templ, err = template.ParseFiles(templates...)
-	if err != nil {
-		return global, err
+	if len(templates) > 0 {
+		// Now load the templates
+		global.templ, err = template.ParseFiles(templates...)
+		if err != nil {
+			return global, err
+		}
 	}
 
 	simulationRand := rand.New(rand.NewPCG(config.Seed1, config.Seed2))
@@ -165,6 +167,10 @@ func (g *Global) GetStartupTasks() []*Task {
 	tasks := make([]*Task, 0, len(g.Schedules))
 	for _, schedule := range g.Schedules {
 		if schedule.OnStartup() {
+			if schedule.Task == nil {
+				clog.Error("startup task not found")
+				continue
+			}
 			tasks = append(tasks, schedule.Task)
 		}
 	}
@@ -176,6 +182,10 @@ func (g *Global) GetTimerTasks() []Timer {
 	for _, schedule := range g.Schedules {
 		duration := schedule.OnTimer()
 		if duration > 0 {
+			if schedule.Task == nil {
+				clog.Error("scheduled task not found")
+				continue
+			}
 			timers = append(timers, Timer{schedule.Task, duration})
 		}
 	}
@@ -191,7 +201,7 @@ func (g *Global) StartTimers() {
 				clog.Debugf("running timer task %s", timer.task.Name)
 				err := timer.task.Execute()
 				if err != nil {
-					clog.Error(err)
+					clog.Errorf("timer task %s failed: %s", timer.task.Name, err)
 				}
 			}
 		}(timer)

lib/task.go

@@ -2,6 +2,7 @@ package lib
 
 import (
 	"bytes"
+	"fmt"
 	"io"
 	"time"
 
@@ -50,6 +51,9 @@ func NewTask(global *Global, name string, config cfg.Task, simulate bool) (*Task
 func (t *Task) Execute() error {
 	var stdin io.Reader
 	if t.InputTemplate != "" {
+		if t.global.templ == nil || t.global.Templates[t.InputTemplate] == nil {
+			return fmt.Errorf("template %s not found", t.InputTemplate)
+		}
 		input := &bytes.Buffer{}
 		err := t.global.templ.ExecuteTemplate(input, t.global.Templates[t.InputTemplate].ID, t.global)
 		if err != nil {

main.go

@@ -82,7 +82,7 @@ func main() {
 		clog.Debugf("running startup task %s", task.Name)
 		err := task.Execute()
 		if err != nil {
-			clog.Error(err)
+			clog.Errorf("startup task %s failed: %s", task.Name, err)
 			continue
 		}
 	}