Initial commit: IT Nexus Web-App

nexus-scanner/cmd/nexus-scanner/main.go

@@ -0,0 +1,156 @@
+package main
+
+import (
+	"context"
+	"log/slog"
+	"os"
+	"os/signal"
+	"syscall"
+	"time"
+
+	"github.com/cereda-systems/nexus-scanner/internal/config"
+	"github.com/cereda-systems/nexus-scanner/internal/db"
+	"github.com/cereda-systems/nexus-scanner/internal/module"
+	arpmod      "github.com/cereda-systems/nexus-scanner/internal/modules/arp"
+	admod       "github.com/cereda-systems/nexus-scanner/internal/modules/adsync"
+	dnsmod      "github.com/cereda-systems/nexus-scanner/internal/modules/dnsreverse"
+	vendormod   "github.com/cereda-systems/nexus-scanner/internal/modules/macvendor"
+	reportermod "github.com/cereda-systems/nexus-scanner/internal/modules/nexusreporter"
+	portscanmod "github.com/cereda-systems/nexus-scanner/internal/modules/portscan"
+	sitemon     "github.com/cereda-systems/nexus-scanner/internal/modules/sitemon"
+	snmpmod     "github.com/cereda-systems/nexus-scanner/internal/modules/snmpmod"
+	sysarpmod   "github.com/cereda-systems/nexus-scanner/internal/modules/sysarp"
+	"github.com/cereda-systems/nexus-scanner/internal/scheduler"
+	"github.com/cereda-systems/nexus-scanner/internal/web"
+)
+
+var version = "dev"
+
+func main() {
+	cfgPath := "/etc/nexus-scanner/config.yaml"
+	if len(os.Args) > 1 {
+		cfgPath = os.Args[1]
+	}
+
+	cfg, err := config.Load(cfgPath)
+	if err != nil {
+		slog.Error("failed to load config", "path", cfgPath, "err", err)
+		os.Exit(1)
+	}
+
+	// Log buffer captures entries for the /logs web page.
+	logBuf := web.NewLogBuffer(500)
+
+	level := slog.LevelInfo
+	if cfg.LogLevel == "debug" {
+		level = slog.LevelDebug
+	}
+	inner := slog.NewJSONHandler(os.Stdout, &slog.HandlerOptions{Level: level})
+	handler := web.NewSlogHandler(inner, logBuf)
+	slog.SetDefault(slog.New(handler))
+
+	slog.Info("nexus-scanner starting", "version", version, "site", cfg.Site)
+
+	store, err := db.Open(cfg.DB.Path)
+	if err != nil {
+		slog.Error("failed to open database", "path", cfg.DB.Path, "err", err)
+		os.Exit(1)
+	}
+	defer store.Close()
+
+	registry := module.NewRegistry()
+
+	// sys_arp: reads the OS ARP cache — works on Windows, Linux and macOS
+	// without raw-socket privileges. Always enabled.
+	registry.Register(sysarpmod.New(cfg.Site, store))
+	slog.Info("module registered", "module", "sys_arp")
+
+	// dns_reverse: enriches known hosts with reverse-DNS hostnames.
+	registry.Register(dnsmod.New(cfg.Site, store))
+	slog.Info("module registered", "module", "dns_reverse")
+
+	// mac_vendor: assigns OUI-based vendor names to known hosts (runs once at startup).
+	registry.Register(vendormod.New(cfg.Site, store))
+	slog.Info("module registered", "module", "mac_vendor")
+
+	// ad_sync: queries Active Directory for all computer objects.
+	if cfg.Modules.ADSync.Enabled {
+		registry.Register(admod.New(cfg.Site, cfg.Modules.ADSync, store))
+		slog.Info("module registered", "module", "ad_sync",
+			"server", cfg.Modules.ADSync.Server,
+			"search_base", cfg.Modules.ADSync.SearchBase,
+		)
+	}
+
+	// site_monitoring: availability checks (ping, http, tcp) — always enabled,
+	// checks are managed via the web UI.
+	cfg.Modules.SiteMonitoring.Enabled = true
+	registry.Register(sitemon.New(cfg.Site, cfg.Modules.SiteMonitoring, cfg.Alert, *cfg, store))
+	slog.Info("module registered", "module", "site_monitoring",
+		"interval", cfg.Modules.SiteMonitoring.Interval)
+
+	// port_scan: TCP port scanner for all online hosts.
+	cfg.Modules.PortScan.Enabled = true
+	registry.Register(portscanmod.New(cfg.Site, cfg.Modules.PortScan, store))
+	slog.Info("module registered", "module", "port_scan",
+		"interval", cfg.Modules.PortScan.Interval)
+
+	// snmp: polls SNMP targets for device info (managed via web UI).
+	cfg.Modules.SNMP.Enabled = true
+	registry.Register(snmpmod.New(cfg.Site, cfg.Modules.SNMP, store))
+	slog.Info("module registered", "module", "snmp",
+		"interval", cfg.Modules.SNMP.Interval)
+
+	// nexus_reporter: pushes changed assets to IT Nexus API.
+	if cfg.Nexus.URL != "" && cfg.Nexus.APIKey != "" {
+		cfg.Modules.NexusReporter.Enabled = true
+		registry.Register(reportermod.New(cfg.Site, cfg.Modules.NexusReporter, *cfg, store))
+		slog.Info("module registered", "module", "nexus_reporter")
+	}
+
+	// arp_discovery: full ARP sweep via raw sockets (Linux only).
+	if cfg.Modules.ARPDiscovery.Enabled {
+		registry.Register(arpmod.New(cfg.Site, cfg.Modules.ARPDiscovery, store))
+		slog.Info("module registered", "module", "arp_discovery",
+			"interval", cfg.Modules.ARPDiscovery.Interval,
+			"subnets", cfg.Modules.ARPDiscovery.Subnets,
+		)
+	}
+
+	ctx, stop := signal.NotifyContext(context.Background(), syscall.SIGINT, syscall.SIGTERM)
+	defer stop()
+
+	// Offline-Sweeper: marks hosts as offline when not seen for OfflineAfter duration.
+	go func() {
+		ticker := time.NewTicker(5 * time.Minute)
+		defer ticker.Stop()
+		for {
+			select {
+			case <-ctx.Done():
+				return
+			case <-ticker.C:
+				n, err := store.MarkStaleHostsOffline(cfg.OfflineAfter)
+				if err != nil {
+					slog.Error("offline sweep", "err", err)
+				} else if n > 0 {
+					slog.Info("hosts marked offline", "count", n, "threshold", cfg.OfflineAfter)
+				}
+			}
+		}
+	}()
+
+	sched := scheduler.New(registry)
+	go sched.Run(ctx)
+
+	srv := web.NewServer(cfgPath, cfg, store, registry, logBuf)
+	go func() {
+		if err := srv.ListenAndServe(ctx); err != nil {
+			slog.Error("web server stopped", "err", err)
+			stop()
+		}
+	}()
+
+	slog.Info("nexus-scanner ready", "addr", cfg.Web.Addr)
+	<-ctx.Done()
+	slog.Info("nexus-scanner shutting down")
+}