Encrypted DNS health, comparing a zone's views, --local everywhere

jarld checks the DoT and DoH listeners every 10 minutes as a client would (page, dashboard, jarl encrypted-dns health, jarl_encrypted_dns_up). The Compare views tab and jarl zone diff show what differs between a zone's views, with Use this version. --local works on unlinked zones. A changed certificates.dir is followed by encrypted DNS's tls statements. Sharing an already shared version replaces other views' overrides.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

internal/server/h_compare.go

@@ -0,0 +1,89 @@
+package server
+
+import (
+	"net/http"
+	"strings"
+
+	"jarl/internal/auth"
+	"jarl/internal/engine"
+	"jarl/internal/model"
+)
+
+// zoneCompare: GET /zones/{zone}/compare lines up a zone's records across
+// the views that have it (docs/views.md#linked-zones). ?views=a,b picks the
+// views (default: every view with a primary zone of that name), ?all=1
+// includes the names and types that are the same everywhere.
+func (s *Server) zoneCompare(w http.ResponseWriter, r *http.Request, p *auth.Principal) error {
+	st, err := s.state(r)
+	if err != nil {
+		return err
+	}
+	z, err := s.zoneByPath(r, st, p)
+	if err != nil {
+		// A name in several views is what there is to compare.
+		ref := r.PathValue("zone")
+		if ref == "root" {
+			ref = "."
+		}
+		name, perr := engine.ParseZoneName(ref)
+		if zs := st.ZonesNamed(name); perr != nil || len(zs) < 2 {
+			return err
+		} else {
+			z = zs[0]
+		}
+	}
+	var want []string
+	for _, v := range strings.Split(r.URL.Query().Get("views"), ",") {
+		if v = strings.TrimSpace(v); v != "" {
+			want = append(want, v)
+		}
+	}
+	var zones []*model.Zone
+	for _, o := range st.ZonesNamed(z.Name) {
+		vn := st.ViewName(o)
+		if o.Type != model.ZonePrimary || !p.CanSeeZone(o.Name, vn) || !p.Can(auth.Action{Resource: auth.ResRecords, Zone: o.Name, View: vn}) {
+			continue
+		}
+		if len(want) > 0 && !containsFold(want, vn) {
+			continue
+		}
+		zones = append(zones, o)
+	}
+	st.SortByView(zones)
+	if len(zones) < 2 {
+		return badRequest("zone %s is in only one view (that you may read): there is nothing to compare", engine.Display(z.Name))
+	}
+	rows := engine.CompareZones(st, zones)
+	all := queryBool(r, "all")
+	out := struct {
+		Zone   string              `json:"zone"`
+		Views  []string            `json:"views"`
+		Linked bool                `json:"linked"` // all of them in one link
+		Same   int                 `json:"same"`   // names and types the same everywhere
+		Rows   []engine.CompareRow `json:"rows"`
+	}{Zone: engine.Display(z.Name), Rows: []engine.CompareRow{}, Linked: true}
+	for _, o := range zones {
+		out.Views = append(out.Views, st.ViewName(o))
+		out.Linked = out.Linked && o.LinkGroup != 0 && o.LinkGroup == zones[0].LinkGroup
+	}
+	for _, row := range rows {
+		if row.Same {
+			out.Same++
+			if !all {
+				continue
+			}
+		}
+		out.Rows = append(out.Rows, row)
+	}
+	writeJSON(w, http.StatusOK, out)
+	return nil
+}
+
+func containsFold(list []string, s string) bool {
+	for _, x := range list {
+		if strings.EqualFold(x, s) {
+			return true
+		}
+	}
+	return false
+}