internal/metrics/prometheus_test.go

@@ -44,6 +44,12 @@ func (m *mockStore) AddSiteReturningID(models.Site) (int, error) { return 0, nil
 func (m *mockStore) AddAlertReturningID(string, string, map[string]string) (int, error) {
 	return 0, nil
 }
+func (m *mockStore) SaveCheckFromNode(int, string, int64, bool) error { return nil }
+func (m *mockStore) RegisterNode(models.ProbeNode) error              { return nil }
+func (m *mockStore) GetNode(string) (models.ProbeNode, error)         { return models.ProbeNode{}, nil }
+func (m *mockStore) GetAllNodes() ([]models.ProbeNode, error)         { return nil, nil }
+func (m *mockStore) UpdateNodeLastSeen(string) error                  { return nil }
+func (m *mockStore) DeleteNode(string) error                          { return nil }
 
 func TestMetricsHandler(t *testing.T) {
 	ms := &mockStore{

internal/models/models.go

@@ -52,11 +52,20 @@ type User struct {
 
 type CheckRecord struct {
 	SiteID    int
+	NodeID    string
 	LatencyNs int64
 	IsUp      bool
 	CheckedAt time.Time
 }
 
+type ProbeNode struct {
+	ID       string
+	Name     string
+	Region   string
+	LastSeen time.Time
+	Version  string
+}
+
 type Backup struct {
 	Sites  []Site        `json:"sites"`
 	Alerts []AlertConfig `json:"alerts"`

internal/server/server.go

@@ -243,10 +243,97 @@ func Start(cfg ServerConfig, s store.Store, eng *monitor.Engine) {
 		w.Write([]byte(fmt.Sprintf("Imported %d monitors, %d alerts from Kuma v%s", len(backup.Sites), len(backup.Alerts), kb.Version)))
 	})
 
-	// 6. Prometheus Metrics
+	// 6. Probe Registration
+	mux.HandleFunc("/api/probe/register", func(w http.ResponseWriter, r *http.Request) {
+		if r.Method != "POST" {
+			http.Error(w, "POST required", 405)
+			return
+		}
+		if cfg.ClusterKey == "" || r.Header.Get("X-Upkeep-Secret") != cfg.ClusterKey {
+			http.Error(w, "Unauthorized", 401)
+			return
+		}
+		var req struct {
+			ID      string `json:"id"`
+			Name    string `json:"name"`
+			Region  string `json:"region"`
+			Version string `json:"version"`
+		}
+		if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+			http.Error(w, "Invalid JSON", 400)
+			return
+		}
+		if req.ID == "" {
+			http.Error(w, "id is required", 400)
+			return
+		}
+		if err := s.RegisterNode(models.ProbeNode{
+			ID: req.ID, Name: req.Name, Region: req.Region, Version: req.Version,
+		}); err != nil {
+			log.Printf("Probe register failed: %v", err)
+			http.Error(w, "Registration failed", 500)
+			return
+		}
+		json.NewEncoder(w).Encode(map[string]bool{"ok": true})
+	})
+
+	// 7. Probe Assignment Fetch
+	mux.HandleFunc("/api/probe/assignments", func(w http.ResponseWriter, r *http.Request) {
+		if cfg.ClusterKey == "" || r.Header.Get("X-Upkeep-Secret") != cfg.ClusterKey {
+			http.Error(w, "Unauthorized", 401)
+			return
+		}
+		sites := eng.GetAllSites()
+		var assigned []models.Site
+		for _, site := range sites {
+			if site.Paused || site.Type == "push" || site.Type == "group" {
+				continue
+			}
+			assigned = append(assigned, site)
+		}
+		w.Header().Set("Content-Type", "application/json")
+		json.NewEncoder(w).Encode(map[string][]models.Site{"sites": assigned})
+	})
+
+	// 8. Probe Result Submission
+	mux.HandleFunc("/api/probe/results", func(w http.ResponseWriter, r *http.Request) {
+		if r.Method != "POST" {
+			http.Error(w, "POST required", 405)
+			return
+		}
+		if cfg.ClusterKey == "" || r.Header.Get("X-Upkeep-Secret") != cfg.ClusterKey {
+			http.Error(w, "Unauthorized", 401)
+			return
+		}
+		var req struct {
+			NodeID  string `json:"node_id"`
+			Results []struct {
+				SiteID    int   `json:"site_id"`
+				LatencyNs int64 `json:"latency_ns"`
+				IsUp      bool  `json:"is_up"`
+			} `json:"results"`
+		}
+		if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+			http.Error(w, "Invalid JSON", 400)
+			return
+		}
+		if req.NodeID == "" {
+			http.Error(w, "node_id is required", 400)
+			return
+		}
+		for _, result := range req.Results {
+			if err := s.SaveCheckFromNode(result.SiteID, req.NodeID, result.LatencyNs, result.IsUp); err != nil {
+				log.Printf("Failed to save probe result: %v", err)
+			}
+		}
+		s.UpdateNodeLastSeen(req.NodeID)
+		json.NewEncoder(w).Encode(map[string]bool{"ok": true})
+	})
+
+	// 9. Prometheus Metrics
 	mux.HandleFunc("/metrics", metrics.Handler(eng))
 
-	// 7. Status Page
+	// 10. Status Page
 	if cfg.EnableStatus {
 		mux.HandleFunc("/status", func(w http.ResponseWriter, r *http.Request) { renderStatusPage(w, cfg.Title, eng) })
 		mux.HandleFunc("/status/json", func(w http.ResponseWriter, r *http.Request) {

internal/store/dialect.go

@@ -10,6 +10,7 @@ type Dialect interface {
 	ResetSequenceOnEmpty(db *sql.DB, table string)
 	ImportWipe(tx *sql.Tx)
 	ImportResetSequences(tx *sql.Tx)
+	UpsertNodeSQL() string
 }
 
 // rewritePlaceholders converts ? markers to $1, $2, etc. for Postgres.

internal/store/postgres.go

@@ -44,6 +44,13 @@ func (d *PostgresDialect) CreateTablesSQL() []string {
 			is_up BOOLEAN, checked_at TIMESTAMP DEFAULT NOW()
 		)`,
 		`CREATE INDEX IF NOT EXISTS idx_check_history_site ON check_history(site_id, checked_at DESC)`,
+		`CREATE TABLE IF NOT EXISTS nodes (
+			id TEXT PRIMARY KEY,
+			name TEXT NOT NULL,
+			region TEXT DEFAULT '',
+			last_seen TIMESTAMP DEFAULT NOW(),
+			version TEXT DEFAULT ''
+		)`,
 	}
 }
 
@@ -60,9 +67,14 @@ func (d *PostgresDialect) MigrationsSQL() []string {
 		"ALTER TABLE sites ADD COLUMN IF NOT EXISTS dns_server TEXT DEFAULT ''",
 		"ALTER TABLE sites ADD COLUMN IF NOT EXISTS ignore_tls BOOLEAN DEFAULT FALSE",
 		"ALTER TABLE sites ADD COLUMN IF NOT EXISTS paused BOOLEAN DEFAULT FALSE",
+		"ALTER TABLE check_history ADD COLUMN IF NOT EXISTS node_id TEXT DEFAULT ''",
 	}
 }
 
+func (d *PostgresDialect) UpsertNodeSQL() string {
+	return "INSERT INTO nodes (id, name, region, last_seen, version) VALUES ($1, $2, $3, NOW(), $4) ON CONFLICT (id) DO UPDATE SET name = EXCLUDED.name, region = EXCLUDED.region, last_seen = NOW(), version = EXCLUDED.version"
+}
+
 func (d *PostgresDialect) ResetSequenceOnEmpty(db *sql.DB, table string) {}
 
 func (d *PostgresDialect) ImportWipe(tx *sql.Tx) {

internal/store/sqlite.go

@@ -44,6 +44,13 @@ func (d *SQLiteDialect) CreateTablesSQL() []string {
 			is_up BOOLEAN, checked_at DATETIME DEFAULT CURRENT_TIMESTAMP
 		)`,
 		`CREATE INDEX IF NOT EXISTS idx_check_history_site ON check_history(site_id, checked_at DESC)`,
+		`CREATE TABLE IF NOT EXISTS nodes (
+			id TEXT PRIMARY KEY,
+			name TEXT NOT NULL,
+			region TEXT DEFAULT '',
+			last_seen DATETIME DEFAULT CURRENT_TIMESTAMP,
+			version TEXT DEFAULT ''
+		)`,
 	}
 }
 
@@ -60,9 +67,14 @@ func (d *SQLiteDialect) MigrationsSQL() []string {
 		"ALTER TABLE sites ADD COLUMN dns_server TEXT DEFAULT ''",
 		"ALTER TABLE sites ADD COLUMN ignore_tls BOOLEAN DEFAULT 0",
 		"ALTER TABLE sites ADD COLUMN paused BOOLEAN DEFAULT 0",
+		"ALTER TABLE check_history ADD COLUMN node_id TEXT DEFAULT ''",
 	}
 }
 
+func (d *SQLiteDialect) UpsertNodeSQL() string {
+	return "INSERT OR REPLACE INTO nodes (id, name, region, last_seen, version) VALUES (?, ?, ?, CURRENT_TIMESTAMP, ?)"
+}
+
 func (d *SQLiteDialect) ResetSequenceOnEmpty(db *sql.DB, table string) {
 	var count int
 	db.QueryRow("SELECT COUNT(*) FROM " + table).Scan(&count)

internal/store/sqlstore.go

@@ -247,7 +247,11 @@ func (s *SQLStore) DeleteUser(id int) error {
 }
 
 func (s *SQLStore) SaveCheck(siteID int, latencyNs int64, isUp bool) error {
-	_, err := s.db.Exec(s.q("INSERT INTO check_history (site_id, latency_ns, is_up) VALUES (?, ?, ?)"), siteID, latencyNs, isUp)
+	return s.SaveCheckFromNode(siteID, "", latencyNs, isUp)
+}
+
+func (s *SQLStore) SaveCheckFromNode(siteID int, nodeID string, latencyNs int64, isUp bool) error {
+	_, err := s.db.Exec(s.q("INSERT INTO check_history (site_id, node_id, latency_ns, is_up) VALUES (?, ?, ?, ?)"), siteID, nodeID, latencyNs, isUp)
 	if err != nil {
 		return err
 	}
@@ -257,6 +261,45 @@ func (s *SQLStore) SaveCheck(siteID int, latencyNs int64, isUp bool) error {
 	return err
 }
 
+func (s *SQLStore) RegisterNode(node models.ProbeNode) error {
+	_, err := s.db.Exec(s.dialect.UpsertNodeSQL(), node.ID, node.Name, node.Region, node.Version)
+	return err
+}
+
+func (s *SQLStore) GetNode(id string) (models.ProbeNode, error) {
+	var n models.ProbeNode
+	err := s.db.QueryRow(s.q("SELECT id, name, region, last_seen, version FROM nodes WHERE id = ?"), id).
+		Scan(&n.ID, &n.Name, &n.Region, &n.LastSeen, &n.Version)
+	return n, err
+}
+
+func (s *SQLStore) GetAllNodes() ([]models.ProbeNode, error) {
+	rows, err := s.db.Query("SELECT id, name, region, last_seen, version FROM nodes ORDER BY region, name")
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	var nodes []models.ProbeNode
+	for rows.Next() {
+		var n models.ProbeNode
+		if err := rows.Scan(&n.ID, &n.Name, &n.Region, &n.LastSeen, &n.Version); err != nil {
+			return nodes, err
+		}
+		nodes = append(nodes, n)
+	}
+	return nodes, rows.Err()
+}
+
+func (s *SQLStore) UpdateNodeLastSeen(id string) error {
+	_, err := s.db.Exec(s.q("UPDATE nodes SET last_seen = CURRENT_TIMESTAMP WHERE id = ?"), id)
+	return err
+}
+
+func (s *SQLStore) DeleteNode(id string) error {
+	_, err := s.db.Exec(s.q("DELETE FROM nodes WHERE id = ?"), id)
+	return err
+}
+
 func (s *SQLStore) LoadAllHistory(limit int) (map[int][]models.CheckRecord, error) {
 	result := make(map[int][]models.CheckRecord)
 	rows, err := s.db.Query(s.q(`

internal/store/store.go

@@ -35,8 +35,16 @@ type Store interface {
 
 	// History
 	SaveCheck(siteID int, latencyNs int64, isUp bool) error
+	SaveCheckFromNode(siteID int, nodeID string, latencyNs int64, isUp bool) error
 	LoadAllHistory(limit int) (map[int][]models.CheckRecord, error)
 
+	// Nodes
+	RegisterNode(node models.ProbeNode) error
+	GetNode(id string) (models.ProbeNode, error)
+	GetAllNodes() ([]models.ProbeNode, error)
+	UpdateNodeLastSeen(id string) error
+	DeleteNode(id string) error
+
 	// Backup & Restore
 	ExportData() (models.Backup, error)
 	ImportData(data models.Backup) error