Feature: Task Scheduler - planned tasks with webhook support

backend/api/handlers.go

@@ -80,6 +80,13 @@ func (h *Handler) SetupRoutes(mux *http.ServeMux, hub *ws.Hub) {
 	mux.HandleFunc("POST /api/v1/installer/upload", h.uploadInstaller)
 	mux.HandleFunc("GET /api/v1/installer/download", h.downloadInstaller)
 
+	// Task-Routes
+	mux.HandleFunc("GET /api/v1/tasks", h.listTasks)
+	mux.HandleFunc("GET /api/v1/tasks/{id}", h.getTask)
+	mux.HandleFunc("POST /api/v1/tasks", h.createTask(hub))
+	mux.HandleFunc("DELETE /api/v1/tasks/{id}", h.deleteTask)
+	mux.HandleFunc("POST /api/v1/tasks/{id}/cancel", h.cancelTask)
+
 	// WebSocket und Tunnel-Routes
 	h.setupTunnelRoutes(mux, hub)
 }

backend/api/scheduler.go

@@ -0,0 +1,244 @@
+package api
+
+import (
+	"bytes"
+	"encoding/base64"
+	"encoding/json"
+	"fmt"
+	"io"
+	"log"
+	"net/http"
+	"time"
+
+	"github.com/cynfo/rmm-backend/db"
+	"github.com/cynfo/rmm-backend/ws"
+)
+
+type TaskScheduler struct {
+	db  *db.Database
+	hub *ws.Hub
+}
+
+func NewTaskScheduler(database *db.Database, hub *ws.Hub) *TaskScheduler {
+	return &TaskScheduler{db: database, hub: hub}
+}
+
+func (s *TaskScheduler) Run() {
+	log.Println("Task-Scheduler gestartet (30s Intervall)")
+	ticker := time.NewTicker(30 * time.Second)
+	defer ticker.Stop()
+
+	// Run once immediately
+	s.processDueTasks()
+
+	for range ticker.C {
+		s.processDueTasks()
+	}
+}
+
+func (s *TaskScheduler) processDueTasks() {
+	tasks, err := s.db.GetDueTasks()
+	if err != nil {
+		log.Printf("Scheduler: Fehler beim Laden faelliger Tasks: %v", err)
+		return
+	}
+
+	for _, task := range tasks {
+		go s.executeTask(task.ID, task.AgentID, task.Action, task.WebhookURL, task.AgentName, task.CustomerName, task.ScheduledAt)
+	}
+}
+
+func (s *TaskScheduler) executeTask(taskID int, agentID, action, webhookURL, agentName, customerName, scheduledAt string) {
+	log.Printf("Scheduler: Starte Task #%d (%s) fuer Agent %s", taskID, action, agentID)
+
+	// Set status to running
+	s.db.UpdateTaskStatus(taskID, "running", nil)
+
+	var result interface{}
+	var taskErr error
+
+	switch action {
+	case "backup":
+		result, taskErr = s.executeBackup(agentID)
+	case "update":
+		result, taskErr = s.executeUpdate(agentID)
+	default:
+		taskErr = fmt.Errorf("unbekannte Aktion: %s", action)
+	}
+
+	// Update status
+	status := "completed"
+	if taskErr != nil {
+		status = "failed"
+		result = map[string]string{"error": taskErr.Error()}
+		log.Printf("Scheduler: Task #%d fehlgeschlagen: %v", taskID, taskErr)
+	} else {
+		log.Printf("Scheduler: Task #%d erfolgreich abgeschlossen", taskID)
+	}
+
+	s.db.UpdateTaskStatus(taskID, status, result)
+
+	// Re-read task for webhook payload
+	task, _ := s.db.GetTask(taskID)
+
+	// Send webhook if configured
+	if webhookURL != "" && task != nil {
+		s.sendWebhook(taskID, webhookURL, task)
+	}
+}
+
+func (s *TaskScheduler) executeBackup(agentID string) (interface{}, error) {
+	if !s.hub.IsAgentConnected(agentID) {
+		return nil, fmt.Errorf("Agent nicht verbunden")
+	}
+
+	cmdID := generateID()
+	cmd := map[string]interface{}{
+		"type":    "command",
+		"id":      cmdID,
+		"command": "backup",
+		"params":  map[string]interface{}{},
+	}
+
+	responseCh := s.hub.RegisterResponseWaiter(cmdID)
+	defer s.hub.UnregisterResponseWaiter(cmdID)
+
+	cmdJSON, _ := json.Marshal(cmd)
+	if err := s.hub.SendToAgent(agentID, cmdJSON); err != nil {
+		return nil, fmt.Errorf("Command senden fehlgeschlagen: %w", err)
+	}
+
+	select {
+	case resp := <-responseCh:
+		respStatus, _ := resp["status"].(string)
+		if respStatus != "ok" {
+			errMsg, _ := resp["error"].(string)
+			return resp, fmt.Errorf("Backup fehlgeschlagen: %s", errMsg)
+		}
+
+		data, ok := resp["data"].(map[string]interface{})
+		if !ok {
+			return resp, fmt.Errorf("ungueltiges Response-Format")
+		}
+
+		// Save backup to DB (same logic as triggerBackup handler)
+		configB64, _ := data["config"].(string)
+		hash, _ := data["hash"].(string)
+		sizeFloat, _ := data["size"].(float64)
+		size := int(sizeFloat)
+
+		configXML, err := base64.StdEncoding.DecodeString(configB64)
+		if err != nil {
+			return nil, fmt.Errorf("Base64-Dekodierung fehlgeschlagen")
+		}
+
+		backupID, isNew, err := s.db.SaveConfigBackup(agentID, hash, size, string(configXML))
+		if err != nil {
+			return nil, fmt.Errorf("Backup speichern fehlgeschlagen: %w", err)
+		}
+
+		msg := "Backup gespeichert"
+		if !isNew {
+			msg = "Config unveraendert (Hash identisch)"
+		}
+
+		return map[string]interface{}{
+			"message":   msg,
+			"backup_id": backupID,
+			"sha256":    hash,
+			"size":      size,
+			"new":       isNew,
+		}, nil
+
+	case <-time.After(60 * time.Second):
+		return nil, fmt.Errorf("Timeout: Agent hat nicht rechtzeitig geantwortet")
+	}
+}
+
+func (s *TaskScheduler) executeUpdate(agentID string) (interface{}, error) {
+	if !s.hub.IsAgentConnected(agentID) {
+		return nil, fmt.Errorf("Agent nicht verbunden")
+	}
+
+	// First: update_check
+	checkCmdID := generateID()
+	checkCmd := map[string]interface{}{
+		"type":    "command",
+		"id":      checkCmdID,
+		"command": "update_check",
+	}
+
+	checkCh := s.hub.RegisterResponseWaiter(checkCmdID)
+	defer s.hub.UnregisterResponseWaiter(checkCmdID)
+
+	checkJSON, _ := json.Marshal(checkCmd)
+	if err := s.hub.SendToAgent(agentID, checkJSON); err != nil {
+		return nil, fmt.Errorf("Update-Check senden fehlgeschlagen: %w", err)
+	}
+
+	var checkResult map[string]interface{}
+	select {
+	case resp := <-checkCh:
+		checkResult = resp
+	case <-time.After(120 * time.Second):
+		return nil, fmt.Errorf("Timeout beim Update-Check")
+	}
+
+	// Then: update
+	updateCmdID := generateID()
+	updateCmd := map[string]interface{}{
+		"type":    "command",
+		"id":      updateCmdID,
+		"command": "update",
+		"params":  map[string]interface{}{"reboot": false},
+	}
+
+	updateCh := s.hub.RegisterResponseWaiter(updateCmdID)
+	defer s.hub.UnregisterResponseWaiter(updateCmdID)
+
+	updateJSON, _ := json.Marshal(updateCmd)
+	if err := s.hub.SendToAgent(agentID, updateJSON); err != nil {
+		return nil, fmt.Errorf("Update-Command senden fehlgeschlagen: %w", err)
+	}
+
+	select {
+	case resp := <-updateCh:
+		respStatus, _ := resp["status"].(string)
+		if respStatus != "ok" {
+			errMsg, _ := resp["error"].(string)
+			return resp, fmt.Errorf("Update fehlgeschlagen: %s", errMsg)
+		}
+		return map[string]interface{}{
+			"message":      "Update ausgefuehrt",
+			"check_result": checkResult,
+			"update_result": resp,
+		}, nil
+	case <-time.After(900 * time.Second):
+		return nil, fmt.Errorf("Timeout beim Update")
+	}
+}
+
+func (s *TaskScheduler) sendWebhook(taskID int, url string, task interface{}) {
+	payload, err := json.Marshal(task)
+	if err != nil {
+		log.Printf("Scheduler: Webhook-Payload fuer Task #%d serialisieren fehlgeschlagen: %v", taskID, err)
+		s.db.SetTaskWebhookResult(taskID, false, fmt.Sprintf("JSON-Fehler: %v", err))
+		return
+	}
+
+	client := &http.Client{Timeout: 10 * time.Second}
+	resp, err := client.Post(url, "application/json", bytes.NewReader(payload))
+	if err != nil {
+		log.Printf("Scheduler: Webhook fuer Task #%d fehlgeschlagen: %v", taskID, err)
+		s.db.SetTaskWebhookResult(taskID, false, fmt.Sprintf("Fehler: %v", err))
+		return
+	}
+	defer resp.Body.Close()
+
+	body, _ := io.ReadAll(io.LimitReader(resp.Body, 512))
+	response := fmt.Sprintf("HTTP %d: %s", resp.StatusCode, string(body))
+
+	sent := resp.StatusCode >= 200 && resp.StatusCode < 300
+	s.db.SetTaskWebhookResult(taskID, sent, response)
+	log.Printf("Scheduler: Webhook fuer Task #%d gesendet (Status: %d)", taskID, resp.StatusCode)
+}

backend/api/tasks.go

@@ -0,0 +1,162 @@
+package api
+
+import (
+	"encoding/json"
+	"log"
+	"net/http"
+	"strconv"
+	"time"
+
+	"github.com/cynfo/rmm-backend/ws"
+)
+
+// GET /api/v1/tasks
+func (h *Handler) listTasks(w http.ResponseWriter, r *http.Request) {
+	limit := 50
+	offset := 0
+	agentID := r.URL.Query().Get("agent_id")
+	status := r.URL.Query().Get("status")
+	action := r.URL.Query().Get("action")
+
+	if l := r.URL.Query().Get("limit"); l != "" {
+		if n, err := strconv.Atoi(l); err == nil && n > 0 {
+			limit = n
+		}
+	}
+	if o := r.URL.Query().Get("offset"); o != "" {
+		if n, err := strconv.Atoi(o); err == nil && n >= 0 {
+			offset = n
+		}
+	}
+
+	tasks, total, err := h.db.GetTasks(limit, offset, agentID, status, action)
+	if err != nil {
+		log.Printf("Tasks laden fehlgeschlagen: %v", err)
+		writeError(w, http.StatusInternalServerError, "Fehler beim Laden")
+		return
+	}
+
+	writeJSON(w, http.StatusOK, map[string]interface{}{
+		"data":  tasks,
+		"total": total,
+	})
+}
+
+// GET /api/v1/tasks/{id}
+func (h *Handler) getTask(w http.ResponseWriter, r *http.Request) {
+	idStr := r.PathValue("id")
+	id, err := strconv.Atoi(idStr)
+	if err != nil {
+		writeError(w, http.StatusBadRequest, "Ungueltige Task-ID")
+		return
+	}
+
+	task, err := h.db.GetTask(id)
+	if err != nil {
+		writeError(w, http.StatusInternalServerError, "Fehler beim Laden")
+		return
+	}
+	if task == nil {
+		writeError(w, http.StatusNotFound, "Task nicht gefunden")
+		return
+	}
+
+	writeJSON(w, http.StatusOK, task)
+}
+
+// POST /api/v1/tasks
+func (h *Handler) createTask(hub *ws.Hub) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		var req struct {
+			AgentID     string `json:"agent_id"`
+			Action      string `json:"action"`
+			ScheduledAt string `json:"scheduled_at"`
+			WebhookURL  string `json:"webhook_url"`
+		}
+		if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+			writeError(w, http.StatusBadRequest, "Ungueltige Anfrage")
+			return
+		}
+
+		if req.AgentID == "" || req.Action == "" {
+			writeError(w, http.StatusBadRequest, "agent_id und action sind erforderlich")
+			return
+		}
+
+		// Validate action
+		if req.Action != "backup" && req.Action != "update" {
+			writeError(w, http.StatusBadRequest, "Ungueltige Aktion (backup, update)")
+			return
+		}
+
+		// Check agent exists
+		agent, _, err := h.db.GetAgent(req.AgentID)
+		if err != nil || agent == nil {
+			writeError(w, http.StatusNotFound, "Agent nicht gefunden")
+			return
+		}
+
+		// Get user from context
+		createdBy := "api-key"
+		if claims, ok := r.Context().Value(UserContextKey).(*JWTClaims); ok {
+			createdBy = claims.Username
+		}
+
+		task, err := h.db.CreateTask(req.AgentID, req.Action, req.ScheduledAt, req.WebhookURL, createdBy)
+		if err != nil {
+			log.Printf("Task erstellen fehlgeschlagen: %v", err)
+			writeError(w, http.StatusInternalServerError, "Task erstellen fehlgeschlagen: "+err.Error())
+			return
+		}
+
+		h.auditLog(r, "task.create", "task", strconv.Itoa(task.ID), agent.Name, req.Action)
+
+		// If scheduled_at is in the past or now, trigger immediate execution
+		if req.ScheduledAt == "" {
+			// Already scheduled for now, scheduler will pick it up within 30s
+		} else {
+			schedTime, err := time.Parse(time.RFC3339, req.ScheduledAt)
+			if err == nil && !schedTime.After(time.Now()) {
+				// In the past — scheduler picks it up
+			}
+		}
+
+		writeJSON(w, http.StatusCreated, task)
+	}
+}
+
+// POST /api/v1/tasks/{id}/cancel
+func (h *Handler) cancelTask(w http.ResponseWriter, r *http.Request) {
+	idStr := r.PathValue("id")
+	id, err := strconv.Atoi(idStr)
+	if err != nil {
+		writeError(w, http.StatusBadRequest, "Ungueltige Task-ID")
+		return
+	}
+
+	if err := h.db.CancelTask(id); err != nil {
+		writeError(w, http.StatusBadRequest, err.Error())
+		return
+	}
+
+	h.auditLog(r, "task.cancel", "task", idStr, "", "")
+	writeJSON(w, http.StatusOK, map[string]string{"message": "Task abgebrochen"})
+}
+
+// DELETE /api/v1/tasks/{id}
+func (h *Handler) deleteTask(w http.ResponseWriter, r *http.Request) {
+	idStr := r.PathValue("id")
+	id, err := strconv.Atoi(idStr)
+	if err != nil {
+		writeError(w, http.StatusBadRequest, "Ungueltige Task-ID")
+		return
+	}
+
+	if err := h.db.DeleteTask(id); err != nil {
+		writeError(w, http.StatusBadRequest, err.Error())
+		return
+	}
+
+	h.auditLog(r, "task.delete", "task", idStr, "", "")
+	writeJSON(w, http.StatusOK, map[string]string{"message": "Task geloescht"})
+}

backend/db/postgres.go

@@ -227,6 +227,24 @@ func (d *Database) migrate() error {
 		d.db.Exec(`INSERT INTO system_settings (key, value) VALUES ($1, '') ON CONFLICT DO NOTHING`, k)
 	}
 
+	// Tasks Tabelle
+	d.db.Exec(`CREATE TABLE IF NOT EXISTS tasks (
+		id SERIAL PRIMARY KEY,
+		agent_id TEXT NOT NULL REFERENCES agents(id) ON DELETE CASCADE,
+		action TEXT NOT NULL,
+		status TEXT NOT NULL DEFAULT 'scheduled',
+		scheduled_at TIMESTAMPTZ NOT NULL,
+		started_at TIMESTAMPTZ,
+		finished_at TIMESTAMPTZ,
+		result JSONB,
+		webhook_url TEXT,
+		webhook_sent BOOLEAN DEFAULT FALSE,
+		webhook_response TEXT,
+		created_by TEXT,
+		created_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
+	)`)
+	d.db.Exec(`CREATE INDEX IF NOT EXISTS idx_tasks_status_scheduled ON tasks(status, scheduled_at)`)
+
 	// Retention Policy (90 Tage)
 	d.setupRetention()
 

backend/db/tasks.go

@@ -0,0 +1,325 @@
+package db
+
+import (
+	"database/sql"
+	"encoding/json"
+	"fmt"
+	"strings"
+	"time"
+
+	"github.com/cynfo/rmm-backend/models"
+)
+
+func (d *Database) CreateTask(agentID, action, scheduledAt, webhookURL, createdBy string) (*models.Task, error) {
+	// Validate action
+	validActions := map[string]bool{"backup": true, "update": true}
+	if !validActions[action] {
+		return nil, fmt.Errorf("ungueltige Aktion: %s", action)
+	}
+
+	var schedTime time.Time
+	var err error
+	if scheduledAt == "" {
+		schedTime = time.Now()
+	} else {
+		schedTime, err = time.Parse(time.RFC3339, scheduledAt)
+		if err != nil {
+			return nil, fmt.Errorf("ungueltiges Datum: %w", err)
+		}
+	}
+
+	var task models.Task
+	err = d.db.QueryRow(`
+		INSERT INTO tasks (agent_id, action, scheduled_at, webhook_url, created_by)
+		VALUES ($1, $2, $3, $4, $5)
+		RETURNING id, agent_id, action, status, scheduled_at, webhook_url, COALESCE(created_by, ''), created_at
+	`, agentID, action, schedTime, webhookURL, createdBy).Scan(
+		&task.ID, &task.AgentID, &task.Action, &task.Status,
+		&schedTime, &task.WebhookURL, &task.CreatedBy, &schedTime,
+	)
+	if err != nil {
+		return nil, fmt.Errorf("Task erstellen: %w", err)
+	}
+
+	// Re-read cleanly
+	return d.GetTask(task.ID)
+}
+
+func (d *Database) GetTask(id int) (*models.Task, error) {
+	var t models.Task
+	var scheduledAt, createdAt time.Time
+	var startedAt, finishedAt sql.NullTime
+	var resultJSON sql.NullString
+	var webhookURL, webhookResponse, createdBy sql.NullString
+	var agentName, customerName sql.NullString
+
+	err := d.db.QueryRow(`
+		SELECT t.id, t.agent_id, COALESCE(a.name, ''), COALESCE(c.name, ''),
+			t.action, t.status, t.scheduled_at, t.started_at, t.finished_at,
+			t.result, t.webhook_url, t.webhook_sent, t.webhook_response,
+			t.created_by, t.created_at
+		FROM tasks t
+		LEFT JOIN agents a ON a.id = t.agent_id
+		LEFT JOIN customers c ON c.id = a.customer_id
+		WHERE t.id = $1
+	`, id).Scan(
+		&t.ID, &t.AgentID, &agentName, &customerName,
+		&t.Action, &t.Status, &scheduledAt, &startedAt, &finishedAt,
+		&resultJSON, &webhookURL, &t.WebhookSent, &webhookResponse,
+		&createdBy, &createdAt,
+	)
+	if err == sql.ErrNoRows {
+		return nil, nil
+	}
+	if err != nil {
+		return nil, err
+	}
+
+	t.AgentName = agentName.String
+	t.CustomerName = customerName.String
+	t.ScheduledAt = scheduledAt.Format(time.RFC3339)
+	t.CreatedAt = createdAt.Format(time.RFC3339)
+	if startedAt.Valid {
+		s := startedAt.Time.Format(time.RFC3339)
+		t.StartedAt = &s
+	}
+	if finishedAt.Valid {
+		s := finishedAt.Time.Format(time.RFC3339)
+		t.FinishedAt = &s
+	}
+	if resultJSON.Valid {
+		var r interface{}
+		json.Unmarshal([]byte(resultJSON.String), &r)
+		t.Result = r
+	}
+	if webhookURL.Valid {
+		t.WebhookURL = webhookURL.String
+	}
+	if webhookResponse.Valid {
+		t.WebhookResponse = webhookResponse.String
+	}
+	if createdBy.Valid {
+		t.CreatedBy = createdBy.String
+	}
+
+	return &t, nil
+}
+
+func (d *Database) GetTasks(limit, offset int, agentID, status, action string) ([]models.Task, int, error) {
+	if limit <= 0 {
+		limit = 50
+	}
+
+	where := []string{}
+	args := []interface{}{}
+	argIdx := 1
+
+	if agentID != "" {
+		where = append(where, fmt.Sprintf("t.agent_id = $%d", argIdx))
+		args = append(args, agentID)
+		argIdx++
+	}
+	if status != "" {
+		where = append(where, fmt.Sprintf("t.status = $%d", argIdx))
+		args = append(args, status)
+		argIdx++
+	}
+	if action != "" {
+		where = append(where, fmt.Sprintf("t.action = $%d", argIdx))
+		args = append(args, action)
+		argIdx++
+	}
+
+	whereClause := ""
+	if len(where) > 0 {
+		whereClause = "WHERE " + strings.Join(where, " AND ")
+	}
+
+	// Count
+	var total int
+	countQuery := "SELECT COUNT(*) FROM tasks t " + whereClause
+	if err := d.db.QueryRow(countQuery, args...).Scan(&total); err != nil {
+		return nil, 0, err
+	}
+
+	// Data
+	query := fmt.Sprintf(`
+		SELECT t.id, t.agent_id, COALESCE(a.name, ''), COALESCE(c.name, ''),
+			t.action, t.status, t.scheduled_at, t.started_at, t.finished_at,
+			t.result, t.webhook_url, t.webhook_sent, t.webhook_response,
+			t.created_by, t.created_at
+		FROM tasks t
+		LEFT JOIN agents a ON a.id = t.agent_id
+		LEFT JOIN customers c ON c.id = a.customer_id
+		%s ORDER BY t.created_at DESC LIMIT $%d OFFSET $%d
+	`, whereClause, argIdx, argIdx+1)
+	args = append(args, limit, offset)
+
+	rows, err := d.db.Query(query, args...)
+	if err != nil {
+		return nil, 0, err
+	}
+	defer rows.Close()
+
+	var tasks []models.Task
+	for rows.Next() {
+		var t models.Task
+		var scheduledAt, createdAt time.Time
+		var startedAt, finishedAt sql.NullTime
+		var resultJSON sql.NullString
+		var webhookURL, webhookResponse, createdBy sql.NullString
+		var agentName, customerName sql.NullString
+
+		if err := rows.Scan(
+			&t.ID, &t.AgentID, &agentName, &customerName,
+			&t.Action, &t.Status, &scheduledAt, &startedAt, &finishedAt,
+			&resultJSON, &webhookURL, &t.WebhookSent, &webhookResponse,
+			&createdBy, &createdAt,
+		); err != nil {
+			return nil, 0, err
+		}
+
+		t.AgentName = agentName.String
+		t.CustomerName = customerName.String
+		t.ScheduledAt = scheduledAt.Format(time.RFC3339)
+		t.CreatedAt = createdAt.Format(time.RFC3339)
+		if startedAt.Valid {
+			s := startedAt.Time.Format(time.RFC3339)
+			t.StartedAt = &s
+		}
+		if finishedAt.Valid {
+			s := finishedAt.Time.Format(time.RFC3339)
+			t.FinishedAt = &s
+		}
+		if resultJSON.Valid {
+			var r interface{}
+			json.Unmarshal([]byte(resultJSON.String), &r)
+			t.Result = r
+		}
+		if webhookURL.Valid {
+			t.WebhookURL = webhookURL.String
+		}
+		if webhookResponse.Valid {
+			t.WebhookResponse = webhookResponse.String
+		}
+		if createdBy.Valid {
+			t.CreatedBy = createdBy.String
+		}
+
+		tasks = append(tasks, t)
+	}
+	if tasks == nil {
+		tasks = []models.Task{}
+	}
+	return tasks, total, rows.Err()
+}
+
+func (d *Database) UpdateTaskStatus(id int, status string, result interface{}) error {
+	var resultJSON *string
+	if result != nil {
+		b, err := json.Marshal(result)
+		if err == nil {
+			s := string(b)
+			resultJSON = &s
+		}
+	}
+
+	now := time.Now().UTC()
+
+	switch status {
+	case "running":
+		_, err := d.db.Exec(
+			"UPDATE tasks SET status = $1, started_at = $2 WHERE id = $3",
+			status, now, id,
+		)
+		return err
+	case "completed", "failed":
+		_, err := d.db.Exec(
+			"UPDATE tasks SET status = $1, finished_at = $2, result = $3 WHERE id = $4",
+			status, now, resultJSON, id,
+		)
+		return err
+	default:
+		_, err := d.db.Exec("UPDATE tasks SET status = $1 WHERE id = $2", status, id)
+		return err
+	}
+}
+
+func (d *Database) SetTaskWebhookResult(id int, sent bool, response string) error {
+	// Truncate response to 500 chars
+	if len(response) > 500 {
+		response = response[:500]
+	}
+	_, err := d.db.Exec(
+		"UPDATE tasks SET webhook_sent = $1, webhook_response = $2 WHERE id = $3",
+		sent, response, id,
+	)
+	return err
+}
+
+func (d *Database) GetDueTasks() ([]models.Task, error) {
+	rows, err := d.db.Query(`
+		SELECT t.id, t.agent_id, COALESCE(a.name, ''), COALESCE(c.name, ''),
+			t.action, t.status, t.scheduled_at, t.webhook_url, t.created_at
+		FROM tasks t
+		LEFT JOIN agents a ON a.id = t.agent_id
+		LEFT JOIN customers c ON c.id = a.customer_id
+		WHERE t.status = 'scheduled' AND t.scheduled_at <= NOW()
+		ORDER BY t.scheduled_at ASC
+	`)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	var tasks []models.Task
+	for rows.Next() {
+		var t models.Task
+		var scheduledAt, createdAt time.Time
+		var webhookURL sql.NullString
+		var agentName, customerName sql.NullString
+
+		if err := rows.Scan(
+			&t.ID, &t.AgentID, &agentName, &customerName,
+			&t.Action, &t.Status, &scheduledAt, &webhookURL, &createdAt,
+		); err != nil {
+			return nil, err
+		}
+		t.AgentName = agentName.String
+		t.CustomerName = customerName.String
+		t.ScheduledAt = scheduledAt.Format(time.RFC3339)
+		t.CreatedAt = createdAt.Format(time.RFC3339)
+		if webhookURL.Valid {
+			t.WebhookURL = webhookURL.String
+		}
+		tasks = append(tasks, t)
+	}
+	return tasks, rows.Err()
+}
+
+func (d *Database) CancelTask(id int) error {
+	res, err := d.db.Exec(
+		"UPDATE tasks SET status = 'cancelled' WHERE id = $1 AND status = 'scheduled'",
+		id,
+	)
+	if err != nil {
+		return err
+	}
+	rows, _ := res.RowsAffected()
+	if rows == 0 {
+		return fmt.Errorf("Task nicht gefunden oder nicht mehr im Status 'scheduled'")
+	}
+	return nil
+}
+
+func (d *Database) DeleteTask(id int) error {
+	res, err := d.db.Exec("DELETE FROM tasks WHERE id = $1", id)
+	if err != nil {
+		return err
+	}
+	rows, _ := res.RowsAffected()
+	if rows == 0 {
+		return fmt.Errorf("Task nicht gefunden")
+	}
+	return nil
+}

backend/main.go

@@ -57,6 +57,10 @@ func main() {
 	mon := monitor.New(database)
 	go mon.Run()
 
+	// Task-Scheduler starten
+	scheduler := api.NewTaskScheduler(database, hub)
+	go scheduler.Run()
+
 	// Config API-Keys in DB migrieren (einmalig)
 	database.MigrateConfigAPIKeys(cfg.APIKeys)
 

backend/models/task.go

@@ -0,0 +1,19 @@
+package models
+
+type Task struct {
+	ID              int         `json:"id"`
+	AgentID         string      `json:"agent_id"`
+	AgentName       string      `json:"agent_name,omitempty"`
+	CustomerName    string      `json:"customer_name,omitempty"`
+	Action          string      `json:"action"`
+	Status          string      `json:"status"`
+	ScheduledAt     string      `json:"scheduled_at"`
+	StartedAt       *string     `json:"started_at,omitempty"`
+	FinishedAt      *string     `json:"finished_at,omitempty"`
+	Result          interface{} `json:"result,omitempty"`
+	WebhookURL      string      `json:"webhook_url,omitempty"`
+	WebhookSent     bool        `json:"webhook_sent"`
+	WebhookResponse string      `json:"webhook_response,omitempty"`
+	CreatedBy       string      `json:"created_by,omitempty"`
+	CreatedAt       string      `json:"created_at"`
+}