Initial commit: IT Nexus Web-App

nexus-scanner/internal/modules/nexusreporter/reporter.go

@@ -0,0 +1,130 @@
+// Package nexusreporter pushes newly discovered or changed assets to IT Nexus.
+package nexusreporter
+
+import (
+	"bytes"
+	"context"
+	"crypto/sha256"
+	"encoding/json"
+	"fmt"
+	"log/slog"
+	"net/http"
+	"time"
+
+	"github.com/cereda-systems/nexus-scanner/internal/config"
+	"github.com/cereda-systems/nexus-scanner/internal/db"
+)
+
+const modName = "nexus_reporter"
+
+type Module struct {
+	site   string
+	cfg    config.ReporterConfig
+	nexus  config.Config // full config for URL + APIKey
+	store  *db.Store
+	client *http.Client
+	// last hash per IP to detect changes
+	lastHash map[string][32]byte
+}
+
+// New creates a new IT Nexus reporter module.
+func New(site string, cfg config.ReporterConfig, nexusCfg config.Config, store *db.Store) *Module {
+	return &Module{
+		site:     site,
+		cfg:      cfg,
+		nexus:    nexusCfg,
+		store:    store,
+		client:   &http.Client{Timeout: 15 * time.Second},
+		lastHash: make(map[string][32]byte),
+	}
+}
+
+func (m *Module) Name() string            { return modName }
+func (m *Module) Interval() time.Duration { return m.cfg.Interval }
+
+type assetPayload struct {
+	Site      string    `json:"site"`
+	Version   string    `json:"scanner_version"`
+	ReportedAt time.Time `json:"reported_at"`
+	Assets    []assetItem `json:"assets"`
+}
+
+type assetItem struct {
+	IP        string    `json:"ip"`
+	MAC       string    `json:"mac"`
+	Hostname  string    `json:"hostname"`
+	Vendor    string    `json:"vendor"`
+	Status    string    `json:"status"`
+	FirstSeen time.Time `json:"first_seen"`
+	LastSeen  time.Time `json:"last_seen"`
+}
+
+// Run reports changed/new hosts to IT Nexus.
+func (m *Module) Run(ctx context.Context) error {
+	if m.nexus.Nexus.URL == "" || m.nexus.Nexus.APIKey == "" {
+		slog.Debug("nexus reporter skipped — URL or APIKey not configured")
+		return nil
+	}
+
+	hosts, err := m.store.ListHosts("")
+	if err != nil {
+		return fmt.Errorf("list hosts: %w", err)
+	}
+
+	var changed []assetItem
+	for _, h := range hosts {
+		hash := hostHash(h)
+		if prev, seen := m.lastHash[h.IP]; seen && prev == hash {
+			continue // unchanged
+		}
+		m.lastHash[h.IP] = hash
+		changed = append(changed, assetItem{
+			IP:        h.IP,
+			MAC:       h.MAC,
+			Hostname:  h.Hostname,
+			Vendor:    h.Vendor,
+			Status:    h.Status,
+			FirstSeen: h.FirstSeen,
+			LastSeen:  h.LastSeen,
+		})
+	}
+
+	if len(changed) == 0 {
+		slog.Debug("nexus reporter: no changes")
+		return nil
+	}
+
+	payload := assetPayload{
+		Site:       m.site,
+		Version:    "1.0",
+		ReportedAt: time.Now(),
+		Assets:     changed,
+	}
+
+	body, _ := json.Marshal(payload)
+	url := m.nexus.Nexus.URL + "/api/scanner/assets"
+	req, err := http.NewRequestWithContext(ctx, http.MethodPost, url, bytes.NewReader(body))
+	if err != nil {
+		return fmt.Errorf("build request: %w", err)
+	}
+	req.Header.Set("Content-Type", "application/json")
+	req.Header.Set("X-Scanner-Key", m.nexus.Nexus.APIKey)
+
+	resp, err := m.client.Do(req)
+	if err != nil {
+		return fmt.Errorf("post to nexus: %w", err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode >= 400 {
+		return fmt.Errorf("nexus returned HTTP %d", resp.StatusCode)
+	}
+
+	slog.Info("nexus reporter: assets reported", "count", len(changed), "url", url)
+	return nil
+}
+
+func hostHash(h db.Host) [32]byte {
+	s := h.IP + "|" + h.MAC + "|" + h.Hostname + "|" + h.Vendor + "|" + h.Status
+	return sha256.Sum256([]byte(s))
+}