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/engine/compare.go

@@ -0,0 +1,104 @@
+package engine
+
+import (
+	"fmt"
+	"slices"
+	"strings"
+
+	"jarl/internal/model"
+)
+
+// ViewSet is what one view has for a name and type.
+type ViewSet struct {
+	View    string   `json:"view"`
+	ZoneID  int64    `json:"zone_id"`
+	Records []string `json:"records"`          // data (with TTL and "(disabled)" when set), sorted
+	IDs     []int64  `json:"ids"`              // the records, in the same order
+	Linked  string   `json:"linked,omitempty"` // shared or local, in a linked zone
+}
+
+// CompareRow is one name and type across views.
+type CompareRow struct {
+	Name  string    `json:"name"` // relative to the zone
+	FQDN  string    `json:"fqdn"`
+	Type  string    `json:"type"`
+	Same  bool      `json:"same"`
+	Views []ViewSet `json:"views"` // in the order of the zones given
+}
+
+// CompareZones lines up the records of zones of the same name in
+// different views (docs/views.md#linked-zones), one row per name and type,
+// sorted like a zone file.
+func CompareZones(st *model.State, zones []*model.Zone) []CompareRow {
+	type key struct{ name, typ string }
+	sets := make([]map[key][]*model.Record, len(zones))
+	var keys []key
+	seen := map[key]bool{}
+	var all []*model.Record
+	for i, z := range zones {
+		sets[i] = map[key][]*model.Record{}
+		for _, r := range st.ZoneRecords(z.ID) {
+			k := key{r.Name, r.Type}
+			sets[i][k] = append(sets[i][k], r)
+			if !seen[k] {
+				seen[k] = true
+				keys = append(keys, k)
+				all = append(all, r)
+			}
+		}
+	}
+	if len(zones) > 0 {
+		// Zone file order: the apex first, then by name and type.
+		model.SortRecords(all, zones[0])
+		keys = keys[:0]
+		for _, r := range all {
+			keys = append(keys, key{r.Name, r.Type})
+		}
+	}
+	var out []CompareRow
+	for _, k := range keys {
+		row := CompareRow{FQDN: k.name, Type: k.typ, Same: true}
+		if len(zones) > 0 {
+			row.Name = relName(k.name, zones[0].Name)
+		}
+		var first string
+		for i, z := range zones {
+			vs := ViewSet{View: st.ViewName(z), ZoneID: z.ID, Records: []string{}, IDs: []int64{}}
+			rs := slices.Clone(sets[i][k])
+			slices.SortFunc(rs, func(a, b *model.Record) int { return strings.Compare(strings.ToLower(a.Data), strings.ToLower(b.Data)) })
+			for _, r := range rs {
+				d := r.Data
+				if r.TTL != nil {
+					d = fmt.Sprintf("%s (TTL %d)", d, *r.TTL)
+				}
+				if r.Disabled {
+					d += " (disabled)"
+				}
+				vs.Records = append(vs.Records, d)
+				vs.IDs = append(vs.IDs, r.ID)
+			}
+			if z.LinkGroup != 0 && len(rs) > 0 {
+				vs.Linked = "shared"
+				if rs[0].SharedID == 0 {
+					vs.Linked = "local"
+				}
+			}
+			sig := strings.Join(vs.Records, "\n")
+			if i == 0 {
+				first = sig
+			} else if sig != first {
+				row.Same = false
+			}
+			row.Views = append(row.Views, vs)
+		}
+		out = append(out, row)
+	}
+	return out
+}
+
+func relName(name, zone string) string {
+	if name == zone {
+		return "@"
+	}
+	return strings.TrimSuffix(name, "."+zone)
+}