feat: external importers + uptime monitors (merge plan M1)

Two tracks from the Beszel/Domain-Locker merge plan in ROADMAP.md:

- Importers: POST /api/import/external sniffs Homepage services.yml,
  Homarr JSON, and Dashy conf.yml into sections/items; SettingsDialog
  import now accepts all four formats.
- Monitors (M1): monitors + heartbeats schema, pure checkers for
  http/tcp/ping/dns/keyword/json-query/push, scheduler on app ctx,
  CRUD + check-now + push ingest API, /monitors + /monitors/:id pages
  (wouter), monitor board widget, ServiceDialog monitor opt-in.

Authored By: TDvorak <[email protected]>

Generated with Devin (https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

apps/backend/cmd/dash/main.go

@@ -42,8 +42,11 @@ func main() {
 	}
 	defer func() { _ = sqlDB.Close() }()
 
+	ctx, stop := signal.NotifyContext(context.Background(), syscall.SIGINT, syscall.SIGTERM)
+	defer stop()
+
 	iconsDir := filepath.Join(dataDir, "icons")
-	router := api.NewRouter(logger, sqlDB, iconsDir)
+	router := api.NewRouter(ctx, logger, sqlDB, iconsDir)
 	if err := web.Register(router); err != nil {
 		logger.Fatal("register embedded UI", zap.Error(err))
 	}
@@ -51,9 +54,6 @@ func main() {
 	addr := ":" + envOr("DASH_PORT", "8080")
 	srv := &http.Server{Addr: addr, Handler: router, ReadHeaderTimeout: 10 * time.Second}
 
-	ctx, stop := signal.NotifyContext(context.Background(), syscall.SIGINT, syscall.SIGTERM)
-	defer stop()
-
 	go func() {
 		logger.Info("listening", zap.String("addr", addr), zap.String("data", dataDir))
 		if err := srv.ListenAndServe(); err != nil && !errors.Is(err, http.ErrServerClosed) {

apps/backend/go.mod

@@ -4,8 +4,10 @@ go 1.27
 
 require (
 	github.com/gin-gonic/gin v1.12.0
+	github.com/goccy/go-yaml v1.19.2
 	github.com/pressly/goose/v3 v3.28.0
 	go.uber.org/zap v1.28.0
+	golang.org/x/net v0.58.0
 	modernc.org/sqlite v1.59.0
 )
 
@@ -21,7 +23,6 @@ require (
 	github.com/go-playground/universal-translator v0.18.1 // indirect
 	github.com/go-playground/validator/v10 v10.30.1 // indirect
 	github.com/goccy/go-json v0.10.5 // indirect
-	github.com/goccy/go-yaml v1.19.2 // indirect
 	github.com/google/uuid v1.6.0 // indirect
 	github.com/json-iterator/go v1.1.12 // indirect
 	github.com/klauspost/cpuid/v2 v2.3.0 // indirect
@@ -42,7 +43,6 @@ require (
 	go.uber.org/multierr v1.11.0 // indirect
 	golang.org/x/arch v0.22.0 // indirect
 	golang.org/x/crypto v0.55.0 // indirect
-	golang.org/x/net v0.58.0 // indirect
 	golang.org/x/sync v0.22.0 // indirect
 	golang.org/x/sys v0.47.0 // indirect
 	golang.org/x/text v0.41.0 // indirect

apps/backend/internal/api/api.go

@@ -2,6 +2,7 @@
 package api
 
 import (
+	"context"
 	"crypto/rand"
 	"database/sql"
 	"encoding/hex"
@@ -12,25 +13,33 @@ import (
 	"time"
 
 	"github.com/gin-gonic/gin"
+	"github.com/tdvorak/dash/internal/widget"
 	"go.uber.org/zap"
 )
 
-// Server holds handler dependencies: DB, icon dir, status + widget caches.
+// Server holds handler dependencies: DB, icon dir, logger, caches.
 type Server struct {
 	db       *sql.DB
 	iconsDir string
+	log      *zap.Logger
 	status   *statusCache
 	widgets  *widgetCache
 }
 
 // NewRouter builds the HTTP handler: zap access log, recovery, /api routes.
-func NewRouter(logger *zap.Logger, db *sql.DB, iconsDir string) *gin.Engine {
+// A non-nil ctx starts the monitor scheduler; nil keeps it off (tests).
+func NewRouter(ctx context.Context, logger *zap.Logger, db *sql.DB, iconsDir string) *gin.Engine {
 	s := &Server{
 		db:       db,
 		iconsDir: iconsDir,
+		log:      logger,
 		status:   newStatusCache(60 * time.Second),
 		widgets:  newWidgetCache(30 * time.Second),
 	}
+	widget.Register(&monitorWidget{db: db})
+	if ctx != nil {
+		go s.runScheduler(ctx.Done())
+	}
 
 	r := gin.New()
 	r.Use(accessLog(logger), gin.Recovery())
@@ -51,6 +60,15 @@ func NewRouter(logger *zap.Logger, db *sql.DB, iconsDir string) *gin.Engine {
 	v1.POST("/items/:id/icon", s.uploadIcon)
 	v1.GET("/icons/:file", s.getIcon)
 
+	v1.GET("/monitors", s.listMonitorsH)
+	v1.POST("/monitors", s.createMonitor)
+	v1.GET("/monitors/:id", s.getMonitor)
+	v1.PATCH("/monitors/:id", s.patchMonitor)
+	v1.DELETE("/monitors/:id", s.deleteMonitor)
+	v1.GET("/monitors/:id/heartbeats", s.monitorHeartbeats)
+	v1.POST("/monitors/:id/check", s.checkNow)
+	v1.Any("/push/:token", s.pushIngest)
+
 	v1.GET("/status", s.getStatus)
 	v1.GET("/widgets/types", s.widgetTypes)
 	v1.GET("/widgets/:id/data", s.widgetData)
@@ -58,6 +76,7 @@ func NewRouter(logger *zap.Logger, db *sql.DB, iconsDir string) *gin.Engine {
 	v1.PUT("/settings", s.putSettings)
 	v1.GET("/export", s.exportBoard)
 	v1.POST("/import", s.importBoard)
+	v1.POST("/import/external", s.importExternal)
 
 	return r
 }

apps/backend/internal/api/api_test.go

@@ -22,7 +22,7 @@ func testServer(t *testing.T) *httptest.Server {
 	}
 	t.Cleanup(func() { d.Close() })
 	gin.SetMode(gin.TestMode)
-	return httptest.NewServer(NewRouter(zap.NewNop(), d, t.TempDir()))
+	return httptest.NewServer(NewRouter(nil, zap.NewNop(), d, t.TempDir()))
 }
 
 func do(t *testing.T, method, url, body string) (*http.Response, map[string]any) {
@@ -178,6 +178,209 @@ func TestWidgetEndpoints(t *testing.T) {
 	}
 }
 
+func TestImportExternalHomepage(t *testing.T) {
+	srv := testServer(t)
+	defer srv.Close()
+
+	body := `- Media:
+    - Plex:
+        href: http://plex.local:32400
+        icon: plex
+    - NoLink:
+        description: widget-only entry
+- Apps:
+    - Sonarr:
+        href: https://sonarr.example.com
+        icon: https://icons.example.com/sonarr.png
+`
+	res, _ := do(t, "POST", srv.URL+"/api/import/external", body)
+	if res.StatusCode != http.StatusOK {
+		t.Fatalf("homepage import: %d", res.StatusCode)
+	}
+	var secs []Section
+	resp, err := http.Get(srv.URL + "/api/sections")
+	if err != nil {
+		t.Fatalf("get sections: %v", err)
+	}
+	defer resp.Body.Close()
+	if err := json.NewDecoder(resp.Body).Decode(&secs); err != nil {
+		t.Fatalf("decode: %v", err)
+	}
+	if len(secs) != 2 {
+		t.Fatalf("expected 2 sections, got %+v", secs)
+	}
+	media := secs[0]
+	if media.Name != "Media" || len(media.Items) != 1 {
+		t.Fatalf("bad Media section: %+v", media)
+	}
+	if media.Items[0].Name != "Plex" || len(media.Items[0].URLs) != 1 {
+		t.Fatalf("bad Plex item: %+v", media.Items[0])
+	}
+	if media.Items[0].Icon == "" {
+		t.Fatal("expected resolved CDN icon")
+	}
+	apps := secs[1]
+	if apps.Items[0].Icon != "https://icons.example.com/sonarr.png" {
+		t.Fatalf("icon passthrough failed: %+v", apps.Items[0])
+	}
+}
+
+func TestImportExternalDashy(t *testing.T) {
+	srv := testServer(t)
+	defer srv.Close()
+
+	body := `appConfig:
+  title: test
+sections:
+  - name: Media
+    items:
+      - title: Plex
+        url: http://plex.local
+        icon: favicon
+      - title: Broken
+        url: "notaurl"
+`
+	res, _ := do(t, "POST", srv.URL+"/api/import/external", body)
+	if res.StatusCode != http.StatusOK {
+		t.Fatalf("dashy import: %d", res.StatusCode)
+	}
+	var secs []Section
+	resp, err := http.Get(srv.URL + "/api/sections")
+	if err != nil {
+		t.Fatalf("get sections: %v", err)
+	}
+	defer resp.Body.Close()
+	if err := json.NewDecoder(resp.Body).Decode(&secs); err != nil {
+		t.Fatalf("decode: %v", err)
+	}
+	if len(secs) != 1 || len(secs[0].Items) != 1 {
+		t.Fatalf("bad sections: %+v", secs)
+	}
+	if secs[0].Items[0].Icon != "http://plex.local/favicon.ico" {
+		t.Fatalf("favicon resolution failed: %+v", secs[0].Items[0])
+	}
+}
+
+func TestImportExternalHomarr(t *testing.T) {
+	srv := testServer(t)
+	defer srv.Close()
+
+	body := `{"apps":[{"name":"Plex","url":"http://plex.local","icon":"hl-plex","categoryId":"c1"},{"name":"Sonarr","url":"http://sonarr.local","categoryId":"c1"}],"categories":[{"id":"c1","name":"Media"}]}`
+	res, _ := do(t, "POST", srv.URL+"/api/import/external", body)
+	if res.StatusCode != http.StatusOK {
+		t.Fatalf("homarr import: %d", res.StatusCode)
+	}
+	var secs []Section
+	resp, err := http.Get(srv.URL + "/api/sections")
+	if err != nil {
+		t.Fatalf("get sections: %v", err)
+	}
+	defer resp.Body.Close()
+	if err := json.NewDecoder(resp.Body).Decode(&secs); err != nil {
+		t.Fatalf("decode: %v", err)
+	}
+	if len(secs) != 1 || secs[0].Name != "Media" || len(secs[0].Items) != 2 {
+		t.Fatalf("bad sections: %+v", secs)
+	}
+}
+
+func TestImportExternalRejectsGarbage(t *testing.T) {
+	srv := testServer(t)
+	defer srv.Close()
+	res, body := do(t, "POST", srv.URL+"/api/import/external", `{"foo": 1}`)
+	if res.StatusCode != http.StatusBadRequest {
+		t.Fatalf("expected 400, got %d: %v", res.StatusCode, body)
+	}
+}
+
+func TestMonitorLifecycle(t *testing.T) {
+	srv := testServer(t)
+	defer srv.Close()
+
+	// Target that returns 200.
+	up := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusOK)
+	}))
+	defer up.Close()
+
+	res, mv := do(t, "POST", srv.URL+"/api/monitors", `{"name":"Site","type":"http","url":"`+up.URL+`","intervalS":60}`)
+	if res.StatusCode != http.StatusCreated {
+		t.Fatalf("create: %d %v", res.StatusCode, mv)
+	}
+	id := mv["id"].(string)
+
+	// check-now -> up, heartbeat recorded.
+	res, mv = do(t, "POST", srv.URL+"/api/monitors/"+id+"/check", "")
+	if res.StatusCode != http.StatusOK || mv["status"] != "up" {
+		t.Fatalf("check-now: %d %v", res.StatusCode, mv)
+	}
+	resp, err := http.Get(srv.URL + "/api/monitors/" + id + "/heartbeats")
+	if err != nil {
+		t.Fatalf("heartbeats: %v", err)
+	}
+	var hbs []map[string]any
+	_ = json.NewDecoder(resp.Body).Decode(&hbs)
+	resp.Body.Close()
+	if len(hbs) != 1 || hbs[0]["status"] != "up" {
+		t.Fatalf("expected 1 up heartbeat, got %v", hbs)
+	}
+
+	// pause -> paused + inactive
+	res, mv = do(t, "PATCH", srv.URL+"/api/monitors/"+id, `{"active":false}`)
+	if res.StatusCode != http.StatusOK || mv["status"] != "paused" || mv["active"] != false {
+		t.Fatalf("pause: %v", mv)
+	}
+
+	// delete
+	res, _ = do(t, "DELETE", srv.URL+"/api/monitors/"+id, "")
+	if res.StatusCode != http.StatusNoContent {
+		t.Fatalf("delete: %d", res.StatusCode)
+	}
+	res, _ = do(t, "GET", srv.URL+"/api/monitors/"+id, "")
+	if res.StatusCode != http.StatusNotFound {
+		t.Fatalf("expected 404 after delete, got %d", res.StatusCode)
+	}
+}
+
+func TestMonitorCheckDown(t *testing.T) {
+	srv := testServer(t)
+	defer srv.Close()
+	res, mv := do(t, "POST", srv.URL+"/api/monitors", `{"name":"Dead","type":"http","url":"http://127.0.0.1:1","timeoutS":1}`)
+	if res.StatusCode != http.StatusCreated {
+		t.Fatalf("create: %v", mv)
+	}
+	id := mv["id"].(string)
+	res, mv = do(t, "POST", srv.URL+"/api/monitors/"+id+"/check", "")
+	if res.StatusCode != http.StatusOK || mv["status"] != "down" {
+		t.Fatalf("expected down, got %v", mv)
+	}
+}
+
+func TestPushMonitor(t *testing.T) {
+	srv := testServer(t)
+	defer srv.Close()
+	res, mv := do(t, "POST", srv.URL+"/api/monitors", `{"name":"Backup","type":"push","intervalS":60}`)
+	if res.StatusCode != http.StatusCreated {
+		t.Fatalf("create: %v", mv)
+	}
+	token, _ := mv["pushToken"].(string)
+	if token == "" {
+		t.Fatal("no push token issued")
+	}
+	res, _ = do(t, "GET", srv.URL+"/api/push/"+token+"?msg=done", "")
+	if res.StatusCode != http.StatusOK {
+		t.Fatalf("push: %d", res.StatusCode)
+	}
+	res, mv = do(t, "GET", srv.URL+"/api/monitors/"+mv["id"].(string), "")
+	if mv["status"] != "up" {
+		t.Fatalf("expected up after push, got %v", mv["status"])
+	}
+	res, _ = do(t, "GET", srv.URL+"/api/push/bogus", "")
+	if res.StatusCode != http.StatusNotFound {
+		t.Fatalf("bad token: %d", res.StatusCode)
+	}
+}
+
 func TestMidpoint(t *testing.T) {
 	f := func(v float64) *float64 { return &v }
 	if got := midpoint(nil, nil); got != 1024 {

apps/backend/internal/api/importers.go

@@ -0,0 +1,322 @@
+package api
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"strings"
+
+	"github.com/gin-gonic/gin"
+	"github.com/goccy/go-yaml"
+)
+
+// diBase mirrors the frontend's dashboard-icons CDN root (ServiceDialog).
+const diBase = "https://cdn.jsdelivr.net/gh/homarr-labs/dashboard-icons/png"
+
+// importExternal ingests a foreign dashboard config — Homepage services.yml,
+// Homarr JSON export, or Dashy conf.yml — and replaces the board with it.
+// Format is sniffed from the body; settings are left untouched.
+func (s *Server) importExternal(c *gin.Context) {
+	body, err := io.ReadAll(io.LimitReader(c.Request.Body, 8<<20))
+	if err != nil || len(body) == 0 {
+		fail(c, http.StatusBadRequest, "empty or unreadable body")
+		return
+	}
+	sections, err := parseExternal(body)
+	if err != nil {
+		fail(c, http.StatusBadRequest, err.Error())
+		return
+	}
+	if err := s.replaceBoard(sections, nil); err != nil {
+		failImport(c, err)
+		return
+	}
+	board, err := s.board()
+	if err != nil {
+		fail(c, http.StatusInternalServerError, err.Error())
+		return
+	}
+	c.JSON(http.StatusOK, board)
+}
+
+// parseExternal sniffs the config format: JSON decodes as Homarr; a YAML
+// sequence is Homepage's grouped services list; a YAML mapping carrying
+// `sections` is a Dashy conf.yml.
+func parseExternal(body []byte) ([]Section, error) {
+	var j any
+	if json.Unmarshal(body, &j) == nil {
+		return parseHomarr(j)
+	}
+	var y any
+	if err := yaml.Unmarshal(body, &y); err != nil {
+		return nil, errors.New("unreadable file — expected JSON or YAML")
+	}
+	switch root := y.(type) {
+	case []any:
+		return parseHomepage(root)
+	case map[string]any:
+		if _, ok := root["sections"]; ok {
+			return parseDashy(body)
+		}
+	}
+	return nil, errors.New("unrecognized config — expected a Homepage services.yml, Homarr JSON export, or Dashy conf.yml")
+}
+
+// ---------- Homepage ----------
+
+// parseHomepage walks a services.yml: a sequence of single-key maps
+// (group name -> sequence of single-key service maps). Bare single-key
+// entries at the top level land in an "Imported" section.
+func parseHomepage(groups []any) ([]Section, error) {
+	var secs []Section
+	loose := Section{Name: "Imported"}
+	for _, g := range groups {
+		gm, ok := g.(map[string]any)
+		if !ok {
+			continue
+		}
+		for name, v := range gm {
+			switch val := v.(type) {
+			case []any:
+				sec := Section{Name: name, Items: homepageItems(val)}
+				if len(sec.Items) > 0 {
+					secs = append(secs, sec)
+				}
+			case map[string]any:
+				if it, ok := homepageService(name, val); ok {
+					loose.Items = append(loose.Items, it)
+				}
+			}
+		}
+	}
+	if len(loose.Items) > 0 {
+		secs = append([]Section{loose}, secs...)
+	}
+	if len(secs) == 0 {
+		return nil, errors.New("homepage: no importable services found")
+	}
+	return assignIDs(secs), nil
+}
+
+func homepageItems(list []any) []Item {
+	var items []Item
+	for _, raw := range list {
+		m, ok := raw.(map[string]any)
+		if !ok {
+			continue
+		}
+		for name, fields := range m {
+			fm, _ := fields.(map[string]any)
+			if it, ok := homepageService(name, fm); ok {
+				items = append(items, it)
+			}
+		}
+	}
+	return items
+}
+
+// homepageService maps one service entry. Entries without a reachable URL
+// (pure widget config, bare ping targets) are skipped rather than failing
+// the whole import.
+func homepageService(name string, fields map[string]any) (Item, bool) {
+	u := strOf(fields, "href", "siteMonitor", "ping")
+	if strings.TrimSpace(name) == "" || !validURL(u) {
+		return Item{}, false
+	}
+	return importedItem(name, resolveIcon(strOf(fields, "icon"), u), u), true
+}
+
+// ---------- Homarr ----------
+
+// parseHomarr tolerates Homarr's shifting export shapes: `categories[].apps`,
+// a flat `apps` array grouped by category id, or board `sections[].items`.
+func parseHomarr(root any) ([]Section, error) {
+	m, ok := root.(map[string]any)
+	if !ok {
+		return nil, errors.New("homarr: expected a JSON object")
+	}
+	var secs []Section
+	seen := map[string]bool{}
+	catNames := map[string]string{}
+
+	for _, c := range arrOf(m["categories"]) {
+		cm, _ := c.(map[string]any)
+		if name := strOf(cm, "name"); name != "" {
+			catNames[strOf(cm, "id")] = name
+			if s := sectionFromApps(name, arrOf(cm["apps"]), seen); len(s.Items) > 0 {
+				secs = append(secs, s)
+			}
+		}
+	}
+
+	if apps := arrOf(m["apps"]); len(apps) > 0 {
+		var order []string
+		byCat := map[string][]any{}
+		for _, a := range apps {
+			am, _ := a.(map[string]any)
+			cat := strOf(am, "categoryId", "category")
+			if _, ok := byCat[cat]; !ok {
+				order = append(order, cat)
+			}
+			byCat[cat] = append(byCat[cat], a)
+		}
+		for _, cat := range order {
+			name := catNames[cat]
+			if name == "" {
+				name = "Imported"
+			}
+			if s := sectionFromApps(name, byCat[cat], seen); len(s.Items) > 0 {
+				secs = append(secs, s)
+			}
+		}
+	}
+
+	for _, raw := range arrOf(m["sections"]) {
+		sm, _ := raw.(map[string]any)
+		if s := sectionFromApps(strOf(sm, "name"), arrOf(sm["items"]), seen); len(s.Items) > 0 {
+			secs = append(secs, s)
+		}
+	}
+
+	if len(secs) == 0 {
+		return nil, errors.New("homarr: no apps found")
+	}
+	return assignIDs(secs), nil
+}
+
+func sectionFromApps(name string, apps []any, seen map[string]bool) Section {
+	sec := Section{Name: orDefault(name, "Imported")}
+	for _, a := range apps {
+		am, _ := a.(map[string]any)
+		it, ok := homarrItem(am)
+		if !ok || seen[it.Name+"|"+it.URLs[0].URL] {
+			continue
+		}
+		seen[it.Name+"|"+it.URLs[0].URL] = true
+		sec.Items = append(sec.Items, it)
+	}
+	return sec
+}
+
+func homarrItem(m map[string]any) (Item, bool) {
+	name := strOf(m, "name", "title", "label")
+	u := strOf(m, "url", "href", "appUrl", "externalUrl", "internalUrl")
+	if name == "" || !validURL(u) {
+		return Item{}, false
+	}
+	return importedItem(name, resolveIcon(strOf(m, "icon", "iconUrl"), u), u), true
+}
+
+// ---------- Dashy ----------
+
+type dashyConf struct {
+	Sections []struct {
+		Name  string `yaml:"name"`
+		Items []struct {
+			Title string `yaml:"title"`
+			URL   string `yaml:"url"`
+			Icon  string `yaml:"icon"`
+		} `yaml:"items"`
+	} `yaml:"sections"`
+}
+
+func parseDashy(body []byte) ([]Section, error) {
+	var conf dashyConf
+	if err := yaml.Unmarshal(body, &conf); err != nil {
+		return nil, fmt.Errorf("dashy: malformed conf.yml")
+	}
+	var secs []Section
+	for _, ds := range conf.Sections {
+		sec := Section{Name: orDefault(ds.Name, "Imported")}
+		for _, di := range ds.Items {
+			if di.Title == "" || !validURL(di.URL) {
+				continue
+			}
+			sec.Items = append(sec.Items, importedItem(di.Title, resolveIcon(di.Icon, di.URL), di.URL))
+		}
+		secs = append(secs, sec)
+	}
+	if len(secs) == 0 {
+		return nil, errors.New("dashy: no sections found")
+	}
+	return assignIDs(secs), nil
+}
+
+// ---------- shared ----------
+
+// assignIDs stamps fresh ids and 1024-spaced positions on an imported tree.
+func assignIDs(secs []Section) []Section {
+	for si := range secs {
+		secs[si].ID = newID("s")
+		secs[si].Position = float64(si+1) * 1024
+		for ii := range secs[si].Items {
+			it := &secs[si].Items[ii]
+			it.ID = newID("i")
+			it.SectionID = secs[si].ID
+			it.Kind = orDefault(it.Kind, "service")
+			it.Position = float64(ii+1) * 1024
+			for ui := range it.URLs {
+				it.URLs[ui].ID = newID("u")
+				it.URLs[ui].Position = float64(ui+1) * 1024
+			}
+		}
+	}
+	return secs
+}
+
+func importedItem(name, icon, u string) Item {
+	return Item{Kind: "service", Name: name, Icon: icon, URLs: []URL{{URL: u}}}
+}
+
+// resolveIcon maps a foreign icon reference to a usable URL: passthrough for
+// absolute URLs, favicon derivation for Dashy's `favicon`, the dashboard-icons
+// CDN for prefixed or bare slugs, and "" (letter tile) for local file paths
+// that only existed on the old dashboard.
+func resolveIcon(icon, itemURL string) string {
+	icon = strings.TrimSpace(icon)
+	switch {
+	case icon == "":
+		return ""
+	case strings.HasPrefix(icon, "http://"), strings.HasPrefix(icon, "https://"):
+		return icon
+	case icon == "favicon", icon == "generalfavicon":
+		return faviconOf(itemURL)
+	case strings.ContainsAny(icon, "/.\\"):
+		return ""
+	}
+	lower := strings.ToLower(icon)
+	for _, p := range []string{"si-", "sh-", "hl-", "di-", "mdi-"} {
+		if rest, ok := strings.CutPrefix(lower, p); ok {
+			if rest == "" {
+				return ""
+			}
+			return diBase + "/" + rest + ".png"
+		}
+	}
+	return diBase + "/" + lower + ".png"
+}
+
+func faviconOf(raw string) string {
+	u, err := url.Parse(raw)
+	if err != nil || u.Host == "" {
+		return ""
+	}
+	return u.Scheme + "://" + u.Host + "/favicon.ico"
+}
+
+func arrOf(v any) []any {
+	a, _ := v.([]any)
+	return a
+}
+
+func strOf(m map[string]any, keys ...string) string {
+	for _, k := range keys {
+		if s, ok := m[k].(string); ok && s != "" {
+			return s
+		}
+	}
+	return ""
+}

apps/backend/internal/api/monitors.go

@@ -0,0 +1,549 @@
+package api
+
+import (
+	"context"
+	"database/sql"
+	"encoding/json"
+	"errors"
+	"net/http"
+	"strconv"
+	"time"
+
+	"github.com/gin-gonic/gin"
+	"github.com/tdvorak/dash/internal/monitor"
+	"github.com/tdvorak/dash/internal/widget"
+	"go.uber.org/zap"
+)
+
+// ---------- model ----------
+
+const monitorCols = `id, name, type, url, hostname, port, method, headers, body,
+	keyword, keyword_invert, json_query, expected, dns_type, interval_s, timeout_s,
+	retries, active, status, push_token, tags, notes, position, last_check, created_at`
+
+func scanMonitor(row interface{ Scan(...any) error }) (*monitor.Monitor, error) {
+	var m monitor.Monitor
+	var tags string
+	var invert, active int
+	err := row.Scan(&m.ID, &m.Name, &m.Type, &m.URL, &m.Hostname, &m.Port, &m.Method,
+		&m.Headers, &m.Body, &m.Keyword, &invert, &m.JSONQuery, &m.Expected, &m.DNSType,
+		&m.IntervalS, &m.TimeoutS, &m.Retries, &active, &m.Status, &m.PushToken,
+		&tags, &m.Notes, &m.Position, &m.LastCheck, &m.CreatedAt)
+	if err != nil {
+		return nil, err
+	}
+	m.KeywordInvert = invert != 0
+	m.Active = active != 0
+	_ = json.Unmarshal([]byte(tags), &m.Tags)
+	if m.Tags == nil {
+		m.Tags = []string{}
+	}
+	return &m, nil
+}
+
+func (s *Server) loadMonitor(id string) (*monitor.Monitor, error) {
+	row := s.db.QueryRow(`SELECT `+monitorCols+` FROM monitors WHERE id = ?`, id)
+	return scanMonitor(row)
+}
+
+func (s *Server) loadMonitorByToken(token string) (*monitor.Monitor, error) {
+	row := s.db.QueryRow(`SELECT `+monitorCols+` FROM monitors WHERE push_token = ? AND push_token != ''`, token)
+	return scanMonitor(row)
+}
+
+func (s *Server) listMonitors() ([]monitor.Monitor, error) {
+	rows, err := s.db.Query(`SELECT ` + monitorCols + ` FROM monitors ORDER BY position, name`)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	var out []monitor.Monitor
+	for rows.Next() {
+		m, err := scanMonitor(rows)
+		if err != nil {
+			return nil, err
+		}
+		out = append(out, *m)
+	}
+	return out, rows.Err()
+}
+
+// ---------- uptime stats ----------
+
+type uptimeStats struct {
+	Up         int     `json:"up"`
+	Down       int     `json:"down"`
+	Uptime24h  float64 `json:"uptime24h"`
+	Uptime30d  float64 `json:"uptime30d"`
+	AvgPing24h int     `json:"avgPing24h"`
+}
+
+func (s *Server) monitorStats(id string) uptimeStats {
+	var st uptimeStats
+	pct := func(hours int) float64 {
+		var up, down int
+		_ = s.db.QueryRow(`SELECT COALESCE(SUM(status='up'),0), COALESCE(SUM(status='down'),0)
+			FROM heartbeats WHERE monitor_id = ? AND checked_at >= datetime('now', ?)`,
+			id, "-"+strconv.Itoa(hours)+" hours").Scan(&up, &down)
+		if up+down == 0 {
+			return 100
+		}
+		return float64(up) / float64(up+down) * 100
+	}
+	st.Uptime24h = pct(24)
+	st.Uptime30d = pct(720)
+	_ = s.db.QueryRow(`SELECT COALESCE(AVG(NULLIF(ping_ms,0)),0) FROM heartbeats
+		WHERE monitor_id = ? AND checked_at >= datetime('now','-24 hours')`, id).Scan(&st.AvgPing24h)
+	_ = s.db.QueryRow(`SELECT COALESCE(SUM(status='up'),0), COALESCE(SUM(status='down'),0)
+		FROM heartbeats WHERE monitor_id = ?`, id).Scan(&st.Up, &st.Down)
+	return st
+}
+
+// monitorView is the API shape: the row plus live uptime stats.
+type monitorView struct {
+	*monitor.Monitor
+	Stats uptimeStats `json:"stats"`
+}
+
+// ---------- handlers ----------
+
+func (s *Server) listMonitorsH(c *gin.Context) {
+	ms, err := s.listMonitors()
+	if err != nil {
+		fail(c, http.StatusInternalServerError, err.Error())
+		return
+	}
+	out := make([]monitorView, 0, len(ms))
+	for i := range ms {
+		out = append(out, monitorView{Monitor: &ms[i], Stats: s.monitorStats(ms[i].ID)})
+	}
+	c.JSON(http.StatusOK, out)
+}
+
+// monitorInput is the create/update payload — all fields optional on PATCH.
+type monitorInput struct {
+	Name          *string  `json:"name"`
+	Type          *string  `json:"type"`
+	URL           *string  `json:"url"`
+	Hostname      *string  `json:"hostname"`
+	Port          *int     `json:"port"`
+	Method        *string  `json:"method"`
+	Headers       *string  `json:"headers"`
+	Body          *string  `json:"body"`
+	Keyword       *string  `json:"keyword"`
+	KeywordInvert *bool    `json:"keywordInvert"`
+	JSONQuery     *string  `json:"jsonQuery"`
+	Expected      *string  `json:"expected"`
+	DNSType       *string  `json:"dnsType"`
+	IntervalS     *int     `json:"intervalS"`
+	TimeoutS      *int     `json:"timeoutS"`
+	Retries       *int     `json:"retries"`
+	Active        *bool    `json:"active"`
+	Tags          []string `json:"tags"`
+	Notes         *string  `json:"notes"`
+}
+
+func validMonitorType(t string) bool {
+	for _, v := range monitor.Types() {
+		if v == t {
+			return true
+		}
+	}
+	return false
+}
+
+func strOr(p *string) string {
+	if p == nil {
+		return ""
+	}
+	return *p
+}
+
+func strOr2(p *string, def string) string {
+	if p == nil || *p == "" {
+		return def
+	}
+	return *p
+}
+
+func intOr(p *int) int {
+	if p == nil {
+		return 0
+	}
+	return *p
+}
+
+func intOr2(p *int, def int) int {
+	if p == nil || *p <= 0 {
+		return def
+	}
+	return *p
+}
+
+func boolOr(p *bool) bool { return p != nil && *p }
+
+func boolOr2(p *bool, def bool) bool {
+	if p == nil {
+		return def
+	}
+	return *p
+}
+
+func (s *Server) createMonitor(c *gin.Context) {
+	var in monitorInput
+	if err := c.ShouldBindJSON(&in); err != nil || in.Name == nil || in.Type == nil {
+		fail(c, http.StatusBadRequest, "name and type required")
+		return
+	}
+	if !validMonitorType(*in.Type) {
+		fail(c, http.StatusBadRequest, "invalid type")
+		return
+	}
+	id := newID("m")
+	token := ""
+	if *in.Type == "push" {
+		token = newID("push")
+	}
+	tags, _ := json.Marshal(in.Tags)
+	if in.Tags == nil {
+		tags = []byte("[]")
+	}
+	_, err := s.db.Exec(`INSERT INTO monitors
+		(id, name, type, url, hostname, port, method, headers, body, keyword,
+		 keyword_invert, json_query, expected, dns_type, interval_s, timeout_s,
+		 retries, active, push_token, tags, notes, position)
+		VALUES (?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?)`,
+		id, *in.Name, *in.Type, strOr(in.URL), strOr(in.Hostname), intOr(in.Port),
+		strOr2(in.Method, "GET"), strOr2(in.Headers, "{}"), strOr(in.Body),
+		strOr(in.Keyword), boolOr(in.KeywordInvert), strOr(in.JSONQuery),
+		strOr(in.Expected), strOr2(in.DNSType, "A"), intOr2(in.IntervalS, 60),
+		intOr2(in.TimeoutS, 10), intOr(in.Retries), boolOr2(in.Active, true),
+		token, string(tags), strOr(in.Notes), float64(time.Now().UnixNano())/1e9)
+	if err != nil {
+		fail(c, http.StatusInternalServerError, err.Error())
+		return
+	}
+	m, err := s.loadMonitor(id)
+	if err != nil {
+		fail(c, http.StatusInternalServerError, err.Error())
+		return
+	}
+	c.JSON(http.StatusCreated, monitorView{Monitor: m, Stats: s.monitorStats(id)})
+}
+
+func (s *Server) getMonitor(c *gin.Context) {
+	m, err := s.loadMonitor(c.Param("id"))
+	if notFound(err) {
+		fail(c, http.StatusNotFound, "monitor not found")
+		return
+	}
+	if err != nil {
+		fail(c, http.StatusInternalServerError, err.Error())
+		return
+	}
+	c.JSON(http.StatusOK, monitorView{Monitor: m, Stats: s.monitorStats(m.ID)})
+}
+
+// patchMonitor applies a sparse update; `active` flips pause/resume.
+func (s *Server) patchMonitor(c *gin.Context) {
+	id := c.Param("id")
+	if _, err := s.loadMonitor(id); notFound(err) {
+		fail(c, http.StatusNotFound, "monitor not found")
+		return
+	}
+	var in monitorInput
+	if err := c.ShouldBindJSON(&in); err != nil {
+		fail(c, http.StatusBadRequest, "invalid body")
+		return
+	}
+	if in.Type != nil && !validMonitorType(*in.Type) {
+		fail(c, http.StatusBadRequest, "invalid type")
+		return
+	}
+	setStr := func(col string, p *string) {
+		if p != nil {
+			_, _ = s.db.Exec(`UPDATE monitors SET `+col+` = ? WHERE id = ?`, *p, id)
+		}
+	}
+	setStr("name", in.Name)
+	setStr("type", in.Type)
+	setStr("url", in.URL)
+	setStr("hostname", in.Hostname)
+	setStr("method", in.Method)
+	setStr("headers", in.Headers)
+	setStr("body", in.Body)
+	setStr("keyword", in.Keyword)
+	setStr("json_query", in.JSONQuery)
+	setStr("expected", in.Expected)
+	setStr("dns_type", in.DNSType)
+	setStr("notes", in.Notes)
+	setInt := func(col string, p *int) {
+		if p != nil {
+			_, _ = s.db.Exec(`UPDATE monitors SET `+col+` = ? WHERE id = ?`, *p, id)
+		}
+	}
+	setInt("port", in.Port)
+	setInt("interval_s", in.IntervalS)
+	setInt("timeout_s", in.TimeoutS)
+	setInt("retries", in.Retries)
+	if in.KeywordInvert != nil {
+		_, _ = s.db.Exec(`UPDATE monitors SET keyword_invert = ? WHERE id = ?`, *in.KeywordInvert, id)
+	}
+	if in.Tags != nil {
+		tags, _ := json.Marshal(in.Tags)
+		_, _ = s.db.Exec(`UPDATE monitors SET tags = ? WHERE id = ?`, string(tags), id)
+	}
+	if in.Active != nil {
+		// pause/resume flips the stored status back to pending for a fresh probe
+		status := "pending"
+		if !*in.Active {
+			status = "paused"
+		}
+		_, _ = s.db.Exec(`UPDATE monitors SET active = ?, status = ? WHERE id = ?`, *in.Active, status, id)
+	}
+	m, err := s.loadMonitor(id)
+	if err != nil {
+		fail(c, http.StatusInternalServerError, err.Error())
+		return
+	}
+	c.JSON(http.StatusOK, monitorView{Monitor: m, Stats: s.monitorStats(id)})
+}
+
+func (s *Server) deleteMonitor(c *gin.Context) {
+	res, err := s.db.Exec(`DELETE FROM monitors WHERE id = ?`, c.Param("id"))
+	if err != nil {
+		fail(c, http.StatusInternalServerError, err.Error())
+		return
+	}
+	if n, _ := res.RowsAffected(); n == 0 {
+		fail(c, http.StatusNotFound, "monitor not found")
+		return
+	}
+	c.Status(http.StatusNoContent)
+}
+
+// heartbeats returns the recent check history for charts/logs.
+func (s *Server) monitorHeartbeats(c *gin.Context) {
+	hours, _ := strconv.Atoi(c.DefaultQuery("hours", "24"))
+	if hours <= 0 || hours > 24*30 {
+		hours = 24
+	}
+	rows, err := s.db.Query(`SELECT id, status, ping_ms, msg, cert_expiry, checked_at
+		FROM heartbeats WHERE monitor_id = ? AND checked_at >= datetime('now', ?)
+		ORDER BY checked_at`, c.Param("id"), "-"+strconv.Itoa(hours)+" hours")
+	if err != nil {
+		fail(c, http.StatusInternalServerError, err.Error())
+		return
+	}
+	defer rows.Close()
+	type hb struct {
+		ID         int    `json:"id"`
+		Status     string `json:"status"`
+		PingMs     int    `json:"pingMs"`
+		Msg        string `json:"msg"`
+		CertExpiry int    `json:"certExpiry"`
+		CheckedAt  string `json:"checkedAt"`
+	}
+	out := []hb{}
+	for rows.Next() {
+		var h hb
+		if err := rows.Scan(&h.ID, &h.Status, &h.PingMs, &h.Msg, &h.CertExpiry, &h.CheckedAt); err != nil {
+			fail(c, http.StatusInternalServerError, err.Error())
+			return
+		}
+		out = append(out, h)
+	}
+	c.JSON(http.StatusOK, out)
+}
+
+// checkNow runs one check synchronously and returns the refreshed view.
+func (s *Server) checkNow(c *gin.Context) {
+	m, err := s.loadMonitor(c.Param("id"))
+	if notFound(err) {
+		fail(c, http.StatusNotFound, "monitor not found")
+		return
+	}
+	if err != nil {
+		fail(c, http.StatusInternalServerError, err.Error())
+		return
+	}
+	s.runCheck(m)
+	m, err = s.loadMonitor(m.ID)
+	if err != nil {
+		fail(c, http.StatusInternalServerError, err.Error())
+		return
+	}
+	c.JSON(http.StatusOK, monitorView{Monitor: m, Stats: s.monitorStats(m.ID)})
+}
+
+// pushIngest is the push-monitor endpoint: any hit records an up heartbeat.
+// ?msg= and ?ping= are optional annotations.
+func (s *Server) pushIngest(c *gin.Context) {
+	m, err := s.loadMonitorByToken(c.Param("token"))
+	if err != nil {
+		fail(c, http.StatusNotFound, "unknown push token")
+		return
+	}
+	msg := c.Query("msg")
+	ping, _ := strconv.Atoi(c.Query("ping"))
+	s.writeHeartbeat(m, &monitor.Result{Up: true, PingMs: ping, Msg: msg, CertExpiry: -1})
+	_, _ = s.db.Exec(`UPDATE monitors SET status = 'up', last_check = strftime('%Y-%m-%dT%H:%M:%fZ','now') WHERE id = ?`, m.ID)
+	c.JSON(http.StatusOK, gin.H{"status": "ok"})
+}
+
+// ---------- scheduler ----------
+
+// runScheduler sweeps for due monitors every tick; each check runs in a
+// bounded worker. Push monitors go stale -> down when silent too long.
+func (s *Server) runScheduler(done <-chan struct{}) {
+	tick := time.NewTicker(10 * time.Second)
+	prune := time.NewTicker(time.Hour)
+	defer tick.Stop()
+	defer prune.Stop()
+	for {
+		select {
+		case <-done:
+			return
+		case <-tick.C:
+			s.sweep()
+		case <-prune.C:
+			if _, err := s.db.Exec(`DELETE FROM heartbeats WHERE checked_at < datetime('now','-30 days')`); err != nil {
+				s.log.Error("heartbeat prune", zap.Error(err))
+			}
+		}
+	}
+}
+
+var checkSem = make(chan struct{}, 8)
+
+func (s *Server) sweep() {
+	rows, err := s.db.Query(`SELECT ` + monitorCols + ` FROM monitors
+		WHERE active = 1 AND type != 'push'
+		AND (last_check IS NULL OR datetime(last_check, '+' || interval_s || ' seconds') <= datetime('now'))`)
+	if err != nil {
+		s.log.Error("monitor sweep", zap.Error(err))
+		return
+	}
+	var due []monitor.Monitor
+	for rows.Next() {
+		if m, err := scanMonitor(rows); err == nil {
+			due = append(due, *m)
+		}
+	}
+	rows.Close()
+
+	for i := range due {
+		m := &due[i]
+		checkSem <- struct{}{}
+		go func() {
+			defer func() { <-checkSem }()
+			s.runCheck(m)
+		}()
+	}
+
+	// Push monitors: mark down when no push arrived within 2x interval.
+	if _, err := s.db.Exec(`UPDATE monitors SET status = 'down',
+		last_check = strftime('%Y-%m-%dT%H:%M:%fZ','now')
+		WHERE type = 'push' AND active = 1
+		AND last_check IS NOT NULL
+		AND datetime(last_check, '+' || (2 * interval_s) || ' seconds') <= datetime('now')
+		AND status != 'down'`); err != nil {
+		s.log.Error("push stale sweep", zap.Error(err))
+	}
+}
+
+// runCheck executes one monitor check (with retries) and persists the result.
+func (s *Server) runCheck(m *monitor.Monitor) *monitor.Result {
+	var res *monitor.Result
+	for attempt := 0; attempt <= m.Retries; attempt++ {
+		res = monitor.Check(context.Background(), m)
+		if res.Up || attempt == m.Retries {
+			break
+		}
+		time.Sleep(2 * time.Second)
+	}
+	s.writeHeartbeat(m, res)
+	prev := m.Status
+	next := "down"
+	if res.Up {
+		next = "up"
+	}
+	if _, err := s.db.Exec(`UPDATE monitors SET status = ?, last_check = strftime('%Y-%m-%dT%H:%M:%fZ','now') WHERE id = ?`,
+		next, m.ID); err != nil {
+		s.log.Error("monitor update", zap.Error(err))
+	}
+	if prev != next && prev != "pending" {
+		s.onMonitorTransition(m, prev, next)
+	}
+	return res
+}
+
+func (s *Server) writeHeartbeat(m *monitor.Monitor, res *monitor.Result) {
+	status := "down"
+	if res.Up {
+		status = "up"
+	}
+	if _, err := s.db.Exec(`INSERT INTO heartbeats (monitor_id, status, ping_ms, msg, cert_expiry)
+		VALUES (?,?,?,?,?)`, m.ID, status, res.PingMs, truncate(res.Msg, 300), res.CertExpiry); err != nil {
+		s.log.Error("heartbeat write", zap.Error(err))
+	}
+}
+
+// onMonitorTransition is the alert seam — M2 wires notifications here.
+func (s *Server) onMonitorTransition(m *monitor.Monitor, prev, next string) {
+	s.log.Info("monitor transition",
+		zap.String("monitor", m.Name), zap.String("from", prev), zap.String("to", next))
+}
+
+func truncate(s string, n int) string {
+	if len(s) > n {
+		return s[:n]
+	}
+	return s
+}
+
+// ---------- widget fetcher ----------
+
+// monitorWidget serves board tiles bound to a monitor via config.monitorId.
+type monitorWidget struct{ db *sql.DB }
+
+func (w *monitorWidget) Meta() widget.Type {
+	return widget.Type{
+		Type: "monitor", Name: "Monitor",
+		Description: "Live status of an uptime monitor",
+		Fields: []widget.Field{
+			{Key: "monitorId", Label: "Monitor", Required: true},
+		},
+	}
+}
+
+func (w *monitorWidget) Fetch(_ context.Context, cfg json.RawMessage) (any, error) {
+	var c struct {
+		MonitorID string `json:"monitorId"`
+	}
+	if err := json.Unmarshal(cfg, &c); err != nil || c.MonitorID == "" {
+		return nil, errors.New("config.monitorId required")
+	}
+	row := w.db.QueryRow(`SELECT `+monitorCols+` FROM monitors WHERE id = ?`, c.MonitorID)
+	m, err := scanMonitor(row)
+	if err != nil {
+		return nil, errors.New("monitor not found")
+	}
+	var up, down int
+	var avgPing float64
+	_ = w.db.QueryRow(`SELECT COALESCE(SUM(status='up'),0), COALESCE(SUM(status='down'),0),
+		COALESCE(AVG(NULLIF(ping_ms,0)),0)
+		FROM heartbeats WHERE monitor_id = ? AND checked_at >= datetime('now','-24 hours')`,
+		m.ID).Scan(&up, &down, &avgPing)
+	uptime := 100.0
+	if up+down > 0 {
+		uptime = float64(up) / float64(up+down) * 100
+	}
+	return map[string]any{
+		"name":     m.Name,
+		"status":   m.Status,
+		"uptime24": uptime,
+		"ping":     int(avgPing),
+		"type":     m.Type,
+	}, nil
+}

apps/backend/internal/api/transfer.go

@@ -2,11 +2,26 @@ package api
 
 import (
 	"encoding/json"
+	"errors"
+	"fmt"
 	"net/http"
 
 	"github.com/gin-gonic/gin"
 )
 
+// errBadInput marks payload validation failures so import handlers can map
+// them to 400 while genuine DB failures stay 500.
+var errBadInput = errors.New("invalid import payload")
+
+// failImport maps replaceBoard errors: bad input -> 400, the rest -> 500.
+func failImport(c *gin.Context, err error) {
+	if errors.Is(err, errBadInput) {
+		fail(c, http.StatusBadRequest, err.Error())
+		return
+	}
+	fail(c, http.StatusInternalServerError, err.Error())
+}
+
 // Export is the portable backup shape: version + settings + board tree.
 type Export struct {
 	Version  int                        `json:"version"`
@@ -36,75 +51,10 @@ func (s *Server) importBoard(c *gin.Context) {
 		fail(c, http.StatusBadRequest, "invalid export payload")
 		return
 	}
-
-	tx, err := s.db.Begin()
-	if err != nil {
-		fail(c, http.StatusInternalServerError, err.Error())
+	if err := s.replaceBoard(in.Sections, in.Settings); err != nil {
+		failImport(c, err)
 		return
 	}
-	defer func() { _ = tx.Rollback() }()
-
-	for _, q := range []string{`DELETE FROM urls`, `DELETE FROM items`, `DELETE FROM sections`} {
-		if _, err := tx.Exec(q); err != nil {
-			fail(c, http.StatusInternalServerError, err.Error())
-			return
-		}
-	}
-	for _, sec := range in.Sections {
-		if sec.ID == "" || sec.Name == "" {
-			fail(c, http.StatusBadRequest, "section missing id or name")
-			return
-		}
-		if _, err := tx.Exec(`INSERT INTO sections (id, name, position, collapsed) VALUES (?, ?, ?, ?)`,
-			sec.ID, sec.Name, sec.Position, sec.Collapsed); err != nil {
-			fail(c, http.StatusInternalServerError, err.Error())
-			return
-		}
-		for _, it := range sec.Items {
-			if it.ID == "" || it.Name == "" {
-				fail(c, http.StatusBadRequest, "item missing id or name")
-				return
-			}
-			var cfg any
-			if it.Config != nil {
-				cfg = string(*it.Config)
-			}
-			if _, err := tx.Exec(
-				`INSERT INTO items (id, section_id, kind, name, icon, position, config) VALUES (?, ?, ?, ?, ?, ?, ?)`,
-				it.ID, sec.ID, orDefault(it.Kind, "service"), it.Name, it.Icon, it.Position, cfg); err != nil {
-				fail(c, http.StatusInternalServerError, err.Error())
-				return
-			}
-			for _, u := range it.URLs {
-				if !validURL(u.URL) {
-					fail(c, http.StatusBadRequest, "invalid url: "+u.URL)
-					return
-				}
-				uid := u.ID
-				if uid == "" {
-					uid = newID("u")
-				}
-				if _, err := tx.Exec(`INSERT INTO urls (id, item_id, url, label, position) VALUES (?, ?, ?, ?, ?)`,
-					uid, it.ID, u.URL, u.Label, u.Position); err != nil {
-					fail(c, http.StatusInternalServerError, err.Error())
-					return
-				}
-			}
-		}
-	}
-	for k, v := range in.Settings {
-		if _, err := tx.Exec(
-			`INSERT INTO settings (key, value) VALUES (?, ?)
-			 ON CONFLICT(key) DO UPDATE SET value = excluded.value`, k, string(v)); err != nil {
-			fail(c, http.StatusInternalServerError, err.Error())
-			return
-		}
-	}
-	if err := tx.Commit(); err != nil {
-		fail(c, http.StatusInternalServerError, err.Error())
-		return
-	}
-
 	sections, err := s.board()
 	if err != nil {
 		fail(c, http.StatusInternalServerError, err.Error())
@@ -113,6 +63,66 @@ func (s *Server) importBoard(c *gin.Context) {
 	c.JSON(http.StatusOK, sections)
 }
 
+// replaceBoard swaps all board rows inside one transaction — shared by the
+// Dash export import and the external-config importers.
+func (s *Server) replaceBoard(sections []Section, settings map[string]json.RawMessage) error {
+	tx, err := s.db.Begin()
+	if err != nil {
+		return err
+	}
+	defer func() { _ = tx.Rollback() }()
+
+	for _, q := range []string{`DELETE FROM urls`, `DELETE FROM items`, `DELETE FROM sections`} {
+		if _, err := tx.Exec(q); err != nil {
+			return err
+		}
+	}
+	for _, sec := range sections {
+		if sec.ID == "" || sec.Name == "" {
+			return fmt.Errorf("%w: section missing id or name", errBadInput)
+		}
+		if _, err := tx.Exec(`INSERT INTO sections (id, name, position, collapsed) VALUES (?, ?, ?, ?)`,
+			sec.ID, sec.Name, sec.Position, sec.Collapsed); err != nil {
+			return err
+		}
+		for _, it := range sec.Items {
+			if it.ID == "" || it.Name == "" {
+				return fmt.Errorf("%w: item missing id or name", errBadInput)
+			}
+			var cfg any
+			if it.Config != nil {
+				cfg = string(*it.Config)
+			}
+			if _, err := tx.Exec(
+				`INSERT INTO items (id, section_id, kind, name, icon, position, config) VALUES (?, ?, ?, ?, ?, ?, ?)`,
+				it.ID, sec.ID, orDefault(it.Kind, "service"), it.Name, it.Icon, it.Position, cfg); err != nil {
+				return err
+			}
+			for _, u := range it.URLs {
+				if !validURL(u.URL) {
+					return fmt.Errorf("%w: invalid url: %s", errBadInput, u.URL)
+				}
+				uid := u.ID
+				if uid == "" {
+					uid = newID("u")
+				}
+				if _, err := tx.Exec(`INSERT INTO urls (id, item_id, url, label, position) VALUES (?, ?, ?, ?, ?)`,
+					uid, it.ID, u.URL, u.Label, u.Position); err != nil {
+					return err
+				}
+			}
+		}
+	}
+	for k, v := range settings {
+		if _, err := tx.Exec(
+			`INSERT INTO settings (key, value) VALUES (?, ?)
+			 ON CONFLICT(key) DO UPDATE SET value = excluded.value`, k, string(v)); err != nil {
+			return err
+		}
+	}
+	return tx.Commit()
+}
+
 func orDefault(v, def string) string {
 	if v == "" {
 		return def

apps/backend/internal/db/migrations/0003_monitors.sql

@@ -0,0 +1,45 @@
+-- +goose Up
+-- Uptime monitors and their check history (merge phase M1).
+CREATE TABLE monitors (
+    id             TEXT PRIMARY KEY,
+    name           TEXT NOT NULL,
+    type           TEXT NOT NULL CHECK (type IN ('http','tcp','ping','dns','keyword','json','push')),
+    url            TEXT NOT NULL DEFAULT '',
+    hostname       TEXT NOT NULL DEFAULT '',
+    port           INTEGER NOT NULL DEFAULT 0,
+    method         TEXT NOT NULL DEFAULT 'GET',
+    headers        JSON NOT NULL DEFAULT '{}',
+    body           TEXT NOT NULL DEFAULT '',
+    keyword        TEXT NOT NULL DEFAULT '',
+    keyword_invert INTEGER NOT NULL DEFAULT 0,
+    json_query     TEXT NOT NULL DEFAULT '',
+    expected       TEXT NOT NULL DEFAULT '',
+    dns_type       TEXT NOT NULL DEFAULT 'A',
+    interval_s     INTEGER NOT NULL DEFAULT 60,
+    timeout_s      INTEGER NOT NULL DEFAULT 10,
+    retries        INTEGER NOT NULL DEFAULT 0,
+    active         INTEGER NOT NULL DEFAULT 1,
+    status         TEXT NOT NULL DEFAULT 'pending' CHECK (status IN ('up','down','pending','paused','maintenance')),
+    push_token     TEXT NOT NULL DEFAULT '',
+    tags           JSON NOT NULL DEFAULT '[]',
+    notes          TEXT NOT NULL DEFAULT '',
+    position       REAL NOT NULL DEFAULT 0,
+    last_check     TEXT,
+    created_at     TEXT NOT NULL DEFAULT (strftime('%Y-%m-%dT%H:%M:%fZ', 'now'))
+);
+CREATE INDEX monitors_due ON monitors(active, last_check);
+
+CREATE TABLE heartbeats (
+    id          INTEGER PRIMARY KEY AUTOINCREMENT,
+    monitor_id  TEXT NOT NULL REFERENCES monitors(id) ON DELETE CASCADE,
+    status      TEXT NOT NULL CHECK (status IN ('up','down')),
+    ping_ms     INTEGER NOT NULL DEFAULT 0,
+    msg         TEXT NOT NULL DEFAULT '',
+    cert_expiry INTEGER NOT NULL DEFAULT -1,
+    checked_at  TEXT NOT NULL DEFAULT (strftime('%Y-%m-%dT%H:%M:%fZ', 'now'))
+);
+CREATE INDEX heartbeats_monitor_time ON heartbeats(monitor_id, checked_at);
+
+-- +goose Down
+DROP TABLE heartbeats;
+DROP TABLE monitors;

apps/backend/internal/monitor/monitor.go

@@ -0,0 +1,315 @@
+// Package monitor holds the uptime-check domain: the Monitor model mirroring
+// the monitors table, plus the check implementations the scheduler invokes.
+// No DB access, no HTTP handlers — pure check logic.
+package monitor
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net"
+	"net/http"
+	"strconv"
+	"strings"
+	"time"
+
+	"golang.org/x/net/icmp"
+	"golang.org/x/net/ipv4"
+)
+
+// Monitor mirrors one row of the monitors table.
+type Monitor struct {
+	ID            string    `json:"id"`
+	Name          string    `json:"name"`
+	Type          string    `json:"type"`
+	URL           string    `json:"url"`
+	Hostname      string    `json:"hostname"`
+	Port          int       `json:"port"`
+	Method        string    `json:"method"`
+	Headers       string    `json:"headers"` // JSON object
+	Body          string    `json:"body"`
+	Keyword       string    `json:"keyword"`
+	KeywordInvert bool      `json:"keywordInvert"`
+	JSONQuery     string    `json:"jsonQuery"`
+	Expected      string    `json:"expected"`
+	DNSType       string    `json:"dnsType"`
+	IntervalS     int       `json:"intervalS"`
+	TimeoutS      int       `json:"timeoutS"`
+	Retries       int       `json:"retries"`
+	Active        bool      `json:"active"`
+	Status        string    `json:"status"`
+	PushToken     string    `json:"pushToken,omitempty"`
+	Tags          []string  `json:"tags"`
+	Notes         string    `json:"notes"`
+	Position      float64   `json:"position"`
+	LastCheck     *string   `json:"lastCheck"`
+	CreatedAt     string    `json:"createdAt"`
+}
+
+// Result is the outcome of one check.
+type Result struct {
+	Up         bool
+	PingMs     int
+	Msg        string
+	CertExpiry int // days until TLS cert expiry; -1 when not applicable
+}
+
+// Types lists the check kinds the add-monitor dialog offers.
+func Types() []string {
+	return []string{"http", "tcp", "ping", "dns", "keyword", "json", "push"}
+}
+
+// Check dispatches to the checker for m.Type. Retries happen in the caller.
+func Check(ctx context.Context, m *Monitor) *Result {
+	timeout := time.Duration(m.TimeoutS) * time.Second
+	if timeout <= 0 {
+		timeout = 10 * time.Second
+	}
+	ctx, cancel := context.WithTimeout(ctx, timeout)
+	defer cancel()
+
+	switch m.Type {
+	case "http", "keyword", "json":
+		return checkHTTP(ctx, m)
+	case "tcp":
+		return checkTCP(ctx, m)
+	case "ping":
+		return checkPing(ctx, m)
+	case "dns":
+		return checkDNS(ctx, m)
+	default:
+		return &Result{Msg: "unknown monitor type: " + m.Type}
+	}
+}
+
+func hostOf(m *Monitor) string {
+	if m.Hostname != "" {
+		return m.Hostname
+	}
+	return m.URL
+}
+
+func checkHTTP(ctx context.Context, m *Monitor) *Result {
+	method := m.Method
+	if method == "" {
+		method = http.MethodGet
+	}
+	var body io.Reader
+	if m.Body != "" {
+		body = strings.NewReader(m.Body)
+	}
+	req, err := http.NewRequestWithContext(ctx, method, m.URL, body)
+	if err != nil {
+		return &Result{Msg: "bad url: " + m.URL}
+	}
+	var hdrs map[string]string
+	if json.Unmarshal([]byte(m.Headers), &hdrs) == nil {
+		for k, v := range hdrs {
+			req.Header.Set(k, v)
+		}
+	}
+	if m.Body != "" && req.Header.Get("Content-Type") == "" {
+		req.Header.Set("Content-Type", "application/json")
+	}
+
+	start := time.Now()
+	resp, err := http.DefaultClient.Do(req)
+	ping := int(time.Since(start).Milliseconds())
+	if err != nil {
+		return &Result{Msg: err.Error()}
+	}
+	defer resp.Body.Close()
+
+	res := &Result{PingMs: ping}
+	if resp.TLS != nil && len(resp.TLS.PeerCertificates) > 0 {
+		res.CertExpiry = int(time.Until(resp.TLS.PeerCertificates[0].NotAfter).Hours() / 24)
+	} else {
+		res.CertExpiry = -1
+	}
+
+	switch m.Type {
+	case "keyword", "json":
+		raw, err := io.ReadAll(io.LimitReader(resp.Body, 4<<20))
+		if err != nil {
+			res.Msg = "read body: " + err.Error()
+			return res
+		}
+		if m.Type == "keyword" {
+			found := strings.Contains(string(raw), m.Keyword)
+			if m.KeywordInvert {
+				found = !found
+			}
+			res.Up = found
+			res.Msg = fmt.Sprintf("keyword %q %s", m.Keyword, map[bool]string{true: "found", false: "absent"}[found])
+			return res
+		}
+		return checkJSONBody(res, raw, m)
+	default:
+		res.Up = resp.StatusCode < 400
+		res.Msg = fmt.Sprintf("HTTP %d", resp.StatusCode)
+		return res
+	}
+}
+
+// checkJSONBody walks a dot path ("a.b.0.c") into decoded JSON and compares
+// the leaf to m.Expected.
+func checkJSONBody(res *Result, raw []byte, m *Monitor) *Result {
+	var v any
+	if err := json.Unmarshal(raw, &v); err != nil {
+		res.Msg = "invalid JSON: " + err.Error()
+		return res
+	}
+	for _, key := range strings.Split(m.JSONQuery, ".") {
+		switch n := v.(type) {
+		case map[string]any:
+			v = n[key]
+		case []any:
+			i, err := strconv.Atoi(key)
+			if err != nil || i < 0 || i >= len(n) {
+				res.Msg = "json path missing: " + m.JSONQuery
+				return res
+			}
+			v = n[i]
+		default:
+			res.Msg = "json path missing: " + m.JSONQuery
+			return res
+		}
+	}
+	got := fmt.Sprint(v)
+	res.Up = got == m.Expected
+	res.Msg = fmt.Sprintf("%s = %q (want %q)", m.JSONQuery, got, m.Expected)
+	return res
+}
+
+func checkTCP(ctx context.Context, m *Monitor) *Result {
+	host := hostOf(m)
+	if host == "" {
+		return &Result{Msg: "hostname or url required"}
+	}
+	addr := net.JoinHostPort(host, strconv.Itoa(m.Port))
+	start := time.Now()
+	conn, err := (&net.Dialer{}).DialContext(ctx, "tcp", addr)
+	if err != nil {
+		return &Result{Msg: err.Error()}
+	}
+	_ = conn.Close()
+	return &Result{Up: true, PingMs: int(time.Since(start).Milliseconds()), Msg: "port open"}
+}
+
+// checkPing sends one ICMP echo. Raw sockets need CAP_NET_RAW; the udp4
+// datagram path works unprivileged on Linux via ping_group_range.
+func checkPing(ctx context.Context, m *Monitor) *Result {
+	host := hostOf(m)
+	if host == "" {
+		return &Result{Msg: "hostname required"}
+	}
+	dst, err := net.ResolveIPAddr("ip4", host)
+	if err != nil {
+		if dst, err = net.ResolveIPAddr("ip6", host); err != nil {
+			return &Result{Msg: "resolve: " + err.Error()}
+		}
+	}
+
+	conn, err := icmp.ListenPacket("ip4:icmp", "0.0.0.0")
+	if err != nil {
+		conn, err = icmp.ListenPacket("udp4", "0.0.0.0")
+	}
+	if err != nil {
+		return &Result{Msg: "icmp unavailable (needs cap_net_raw or ping_group_range): " + err.Error()}
+	}
+	defer conn.Close()
+	_ = conn.SetDeadline(time.Now().Add(4 * time.Second))
+
+	wm := icmp.Message{Type: ipv4.ICMPTypeEcho, Code: 0, Body: &icmp.Echo{
+		ID:   1,
+		Seq:  1,
+		Data: []byte("dash"),
+	}}
+	wb, err := wm.Marshal(nil)
+	if err != nil {
+		return &Result{Msg: err.Error()}
+	}
+	start := time.Now()
+	var dstAddr net.Addr = dst
+	if _, err := conn.WriteTo(wb, dstAddr); err != nil {
+		return &Result{Msg: err.Error()}
+	}
+	rb := make([]byte, 1500)
+	for {
+		n, _, err := conn.ReadFrom(rb)
+		if err != nil {
+			return &Result{Msg: "no reply: " + err.Error()}
+		}
+		rm, err := icmp.ParseMessage(ipv4.ICMPTypeEchoReply.Protocol(), rb[:n])
+		if err != nil {
+			continue
+		}
+		if rm.Type == ipv4.ICMPTypeEchoReply {
+			return &Result{Up: true, PingMs: int(time.Since(start).Milliseconds()), Msg: "echo reply"}
+		}
+	}
+}
+
+func checkDNS(ctx context.Context, m *Monitor) *Result {
+	host := hostOf(m)
+	if host == "" {
+		return &Result{Msg: "hostname required"}
+	}
+	r := net.DefaultResolver
+	start := time.Now()
+	var answers []string
+	var err error
+	switch strings.ToUpper(m.DNSType) {
+	case "AAAA":
+		var ips []net.IP
+		ips, err = r.LookupIP(ctx, "ip6", host)
+		for _, ip := range ips {
+			answers = append(answers, ip.String())
+		}
+	case "MX":
+		var mxs []*net.MX
+		mxs, err = r.LookupMX(ctx, host)
+		for _, mx := range mxs {
+			answers = append(answers, mx.Host)
+		}
+	case "NS":
+		var nss []*net.NS
+		nss, err = r.LookupNS(ctx, host)
+		for _, ns := range nss {
+			answers = append(answers, ns.Host)
+		}
+	case "TXT":
+		answers, err = r.LookupTXT(ctx, host)
+	case "CNAME":
+		var c string
+		c, err = r.LookupCNAME(ctx, host)
+		if c != "" {
+			answers = []string{c}
+		}
+	default: // A
+		var ips []net.IP
+		ips, err = r.LookupIP(ctx, "ip4", host)
+		for _, ip := range ips {
+			answers = append(answers, ip.String())
+		}
+	}
+	ping := int(time.Since(start).Milliseconds())
+	if err != nil {
+		return &Result{Msg: err.Error()}
+	}
+	if len(answers) == 0 {
+		return &Result{Msg: "no records"}
+	}
+	res := &Result{Up: true, PingMs: ping, Msg: strings.Join(answers, ", ")}
+	if m.Expected != "" {
+		for _, a := range answers {
+			if strings.Contains(a, m.Expected) {
+				return res
+			}
+		}
+		res.Up = false
+		res.Msg = fmt.Sprintf("no record contains %q (got %s)", m.Expected, res.Msg)
+	}
+	return res
+}

apps/backend/internal/widget/adguard.go

@@ -11,7 +11,7 @@ import (
 // AdGuard Home REST API: GET /control/stats with HTTP basic auth.
 type adguard struct{}
 
-func init() { register(adguard{}) }
+func init() { Register(adguard{}) }
 
 func (adguard) Meta() Type {
 	return Type{

apps/backend/internal/widget/clock.go

@@ -10,7 +10,7 @@ import (
 // it and the add-widget dialog can offer it like any other type.
 type clock struct{}
 
-func init() { register(clock{}) }
+func init() { Register(clock{}) }
 
 func (clock) Meta() Type {
 	return Type{

apps/backend/internal/widget/immich.go

@@ -10,7 +10,7 @@ import (
 // Immich REST API: GET /api/statistics with an x-api-key header.
 type immich struct{}
 
-func init() { register(immich{}) }
+func init() { Register(immich{}) }
 
 func (immich) Meta() Type {
 	return Type{

apps/backend/internal/widget/pihole.go

@@ -11,7 +11,7 @@ import (
 // jarvis: v5 only for now — v6 (/api/...) lands when someone runs it.
 type pihole struct{}
 
-func init() { register(pihole{}) }
+func init() { Register(pihole{}) }
 
 func (pihole) Meta() Type {
 	return Type{

apps/backend/internal/widget/widget.go

@@ -40,7 +40,9 @@ type Fetcher interface {
 
 var registry = map[string]Fetcher{}
 
-func register(f Fetcher) { registry[f.Meta().Type] = f }
+// Register adds a fetcher — used by the api package for DB-backed widgets
+// (monitor/domain/system) that can't live in this leaf package.
+func Register(f Fetcher) { registry[f.Meta().Type] = f }
 
 // Get resolves a config.type to its fetcher.
 func Get(t string) (Fetcher, bool) {