Merge feature/template-placeholders: плейсхолдер {{domain_name}} в шаблонах

Шаблон хранит записи с {{domain_name}}, материализуется под имя зоны при
diff/apply (переиспользуем между доменами); snapshot зоны авто-параметризует
(матчинг по границе DNS-лейбла); подсказка в редакторе.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01BwxdSt4reTm7Dj1oxRvpP3

docs/superpowers/plans/2026-07-05-template-placeholders.md

@@ -0,0 +1,221 @@
+# Шаблоны с плейсхолдером {{domain_name}} Implementation Plan
+
+> **For agentic workers:** REQUIRED SUB-SKILL: superpowers:subagent-driven-development. Steps use `- [ ]`.
+
+**Goal:** Сделать шаблоны переиспользуемыми между доменами через плейсхолдер `{{domain_name}}`: шаблон хранит записи с плейсхолдером, а при diff/apply он материализуется под имя конкретной зоны. Снимок зоны в шаблон авто-параметризуется.
+
+**Architecture:** Плейсхолдер `{{domain_name}}` в именах и значениях записей шаблона. Материализация (подстановка имени зоны без завершающей точки) — централизованно в `service.resolve`, поэтому и diff, и apply работают с уже подставленными значениями. Обратная операция (параметризация) применяется при snapshot зоны в шаблон. Новый пакет `internal/tmpl` изолирует обе операции.
+
+**Tech Stack:** Go (strings), sqlc-модель (правится вручную — sqlc не установлен), React + Vite.
+
+## Global Constraints
+
+- Плейсхолдер: буквально `{{domain_name}}` (константа). Подставляется имя зоны БЕЗ завершающей точки: `strings.TrimSuffix(zoneName, ".")`. Точки в шаблоне — явные (пользователь пишет `_dmarc.{{domain_name}}.`).
+- Материализация применяется в именах записей И во всех значениях (Values).
+- Snapshot (`template-from-zone`) авто-параметризует: заменяет вхождения имени зоны на `{{domain_name}}` в именах и значениях. Записи без вхождений (DKIM-ключ, CNAME на внешний хост) остаются как есть.
+- Материализация — единственная точка истины для diff/apply: НЕ дублировать логику подстановки в провайдере или где-то ещё.
+- sqlc НЕ установлен: `LoadDomainFull` правится вручную и в `internal/store/queries/domains.sql` (источник), и в `internal/store/db/domains.sql.go` (сгенерированный) — держать синхронно.
+- Комментарии в Go — на английском; в web — как в окружающих файлах. TDD. НЕ коммитить реальную сборку `internal/web/dist/*`.
+
+---
+
+### Task 1: Backend — пакет tmpl (материализация/параметризация) + zoneName в resolve + snapshot
+
+**Files:**
+- Create: `internal/tmpl/tmpl.go`, `internal/tmpl/tmpl_test.go`
+- Modify: `internal/service/service.go` (DomainRef.ZoneName + resolve), `internal/store/loader.go` (LoadDomain возвращает ZoneName), `internal/store/queries/domains.sql` + `internal/store/db/domains.sql.go` (LoadDomainFull += zone_name), `internal/api/handlers.go` (handleTemplateFromZone параметризует)
+- Test: `internal/service/service_test.go`, `internal/api/tenant_test.go`
+
+**Interfaces:**
+- Produces: `tmpl.Placeholder = "{{domain_name}}"`; `tmpl.Materialize(doc dto.TemplateDoc, zoneName string) []model.Record`; `tmpl.Parameterize(recs []model.Record, zoneName string) dto.TemplateDoc`; `service.DomainRef.ZoneName`.
+- Consumes: `dto.TemplateDoc`, `dto.RecordDTO`, `model.Record`.
+
+- [ ] **Step 1: Тесты пакета tmpl**
+
+`internal/tmpl/tmpl_test.go`:
+```go
+func TestMaterializeReplacesInNameAndValues(t *testing.T) {
+	doc := dto.TemplateDoc{Records: []dto.RecordDTO{
+		{Type: "TXT", Name: "_dmarc.{{domain_name}}.", TTL: 600, Values: []string{"v=DMARC1; p=quarantine"}},
+		{Type: "MX", Name: "{{domain_name}}.", TTL: 600, Values: []string{"0 pmg2-mail.{{domain_name}}."}},
+		{Type: "TXT", Name: "{{domain_name}}.", TTL: 600, Values: []string{"v=spf1 a:mail.{{domain_name}} ~all"}},
+	}}
+	recs := tmpl.Materialize(doc, "reconops.ru.") // trailing dot stripped
+	if recs[0].Name != "_dmarc.reconops.ru." {
+		t.Fatalf("name: %q", recs[0].Name)
+	}
+	if recs[1].Values[0] != "0 pmg2-mail.reconops.ru." {
+		t.Fatalf("mx value: %q", recs[1].Values[0])
+	}
+	if recs[2].Values[0] != "v=spf1 a:mail.reconops.ru ~all" {
+		t.Fatalf("spf value: %q", recs[2].Values[0])
+	}
+}
+
+func TestParameterizeIsInverseForZoneOccurrences(t *testing.T) {
+	recs := []model.Record{
+		{Type: "TXT", Name: "_dmarc.reconops.ru.", TTL: 600, Values: []string{"v=DMARC1"}},
+		{Type: "TXT", Name: "reconops.ru.", TTL: 600, Values: []string{"v=spf1 a:mail.reconops.ru ~all"}},
+		{Type: "CNAME", Name: "mail.reconops.ru.", TTL: 600, Values: []string{"amail.amega.kz."}}, // external host untouched
+	}
+	doc := tmpl.Parameterize(recs, "reconops.ru.")
+	if doc.Records[0].Name != "_dmarc.{{domain_name}}." {
+		t.Fatalf("name: %q", doc.Records[0].Name)
+	}
+	if doc.Records[1].Values[0] != "v=spf1 a:mail.{{domain_name}} ~all" {
+		t.Fatalf("spf: %q", doc.Records[1].Values[0])
+	}
+	if doc.Records[2].Values[0] != "amail.amega.kz." {
+		t.Fatalf("external cname value must be untouched: %q", doc.Records[2].Values[0])
+	}
+}
+```
+Run: `go test ./internal/tmpl/...` — Ожидание FAIL (пакета нет).
+
+- [ ] **Step 2: Пакет tmpl**
+
+`internal/tmpl/tmpl.go`:
+```go
+// Package tmpl renders reusable DNS templates for a concrete zone.
+//
+// A template stores records containing the {{domain_name}} placeholder; it is
+// materialised (placeholder -> zone name, without the trailing dot) just
+// before diff/apply against a specific domain, and parameterised (zone name
+// -> placeholder) when snapshotting a live zone into a reusable template.
+package tmpl
+
+import (
+	"strings"
+
+	"github.com/vasyakrg/dns-autoresolver/internal/model"
+	"github.com/vasyakrg/dns-autoresolver/internal/store/dto"
+)
+
+const Placeholder = "{{domain_name}}"
+
+func zoneName(z string) string { return strings.TrimSuffix(z, ".") }
+
+// Materialize renders a template's records for the given zone, substituting
+// {{domain_name}} with the zone name (без завершающей точки) in each record's
+// Name and every Value.
+func Materialize(doc dto.TemplateDoc, zone string) []model.Record {
+	z := zoneName(zone)
+	out := make([]model.Record, 0, len(doc.Records))
+	for _, r := range doc.Records {
+		vals := make([]string, len(r.Values))
+		for i, v := range r.Values {
+			vals[i] = strings.ReplaceAll(v, Placeholder, z)
+		}
+		out = append(out, model.Record{
+			Type:   model.RecordType(r.Type),
+			Name:   strings.ReplaceAll(r.Name, Placeholder, z),
+			TTL:    r.TTL,
+			Values: vals,
+		})
+	}
+	return out
+}
+
+// Parameterize replaces occurrences of the zone name with {{domain_name}} in
+// record names and values, so a snapshot of a live zone becomes portable.
+// Records with no zone-name occurrence (DKIM key, external CNAME target) are
+// left unchanged.
+func Parameterize(recs []model.Record, zone string) dto.TemplateDoc {
+	z := zoneName(zone)
+	out := dto.TemplateDoc{Records: make([]dto.RecordDTO, 0, len(recs))}
+	for _, r := range recs {
+		vals := make([]string, len(r.Values))
+		for i, v := range r.Values {
+			vals[i] = strings.ReplaceAll(v, z, Placeholder)
+		}
+		out.Records = append(out.Records, dto.RecordDTO{
+			Type:   string(r.Type),
+			Name:   strings.ReplaceAll(r.Name, z, Placeholder),
+			TTL:    r.TTL,
+			Values: vals,
+		})
+	}
+	return out
+}
+```
+Run: `go test ./internal/tmpl/...` — Ожидание PASS.
+
+- [ ] **Step 3: DomainRef.ZoneName + LoadDomainFull zone_name**
+
+`internal/service/service.go` — `DomainRef` += `ZoneName string`.
+
+`internal/store/queries/domains.sql` — LoadDomainFull:
+```sql
+-- name: LoadDomainFull :one
+SELECT d.zone_id, d.zone_name, a.provider, a.secret_enc, t.doc
+FROM domains d
+JOIN provider_accounts a ON a.id = d.provider_account_id
+LEFT JOIN templates t ON t.id = d.template_id
+WHERE d.id = $1 AND d.project_id = $2;
+```
+`internal/store/db/domains.sql.go` (sqlc НЕ установлен — правь вручную, синхронно): в `loadDomainFull` const добавь `d.zone_name` в SELECT; в `LoadDomainFullRow` добавь `ZoneName string json:"zone_name"` (после ZoneID); в `Scan(...)` добавь `&i.ZoneName` в правильном порядке (сразу после `&i.ZoneID`).
+
+`internal/store/loader.go` — `LoadDomain` возвращает `ZoneName: row.ZoneName` в DomainRef. (LoadZone можно оставить как есть — snapshot берёт zoneName из GetDomain.)
+
+- [ ] **Step 4: resolve материализует**
+
+`internal/service/service.go` resolve — заменить:
+```go
+cs := diff.Diff(ref.Template.ToModel(), actual)
+```
+на:
+```go
+cs := diff.Diff(tmpl.Materialize(ref.Template, ref.ZoneName), actual)
+```
+(импортируй `internal/tmpl`.) Обнови фейки Loader в тестах — LoadDomain должен возвращать ZoneName; добавь тест-кейс, что resolve/Check материализует плейсхолдер (шаблон с `{{domain_name}}` → diff считается против actual с подставленным именем зоны фейкового провайдера).
+
+- [ ] **Step 5: snapshot параметризует**
+
+`internal/api/handlers.go` `handleTemplateFromZone` — после фильтра managed-записей заменить:
+```go
+doc := dto.FromModel(managed)
+```
+на:
+```go
+doc := tmpl.Parameterize(managed, dom.ZoneName)
+```
+(импортируй `internal/tmpl`; `dom.ZoneName` уже есть из GetDomain.) Обнови/добавь тест: snapshot зоны reconops.ru → в созданном шаблоне имена/значения содержат `{{domain_name}}` вместо `reconops.ru` (мок ZoneRecords верни записи с именем зоны, проверь что в CreateTemplate ушёл doc с плейсхолдером).
+
+- [ ] **Step 6: Прогон и коммит**
+
+Run: `go build ./... && go test ./internal/...`. Ожидание PASS.
+```bash
+git add internal/
+git commit -m "feat(tmpl): {{domain_name}} placeholder — materialize on diff/apply, parameterize on snapshot"
+```
+
+---
+
+### Task 2: Frontend — подсказка о плейсхолдере в редакторе шаблонов
+
+**Files:**
+- Modify: `web/src/components/RecordEditor.tsx` (или `web/src/pages/TemplatesPage.tsx` — где логичнее подсказка)
+- Test: соответствующий *.test.tsx
+
+**Interfaces:** только UI-подсказка; поведение diff уже материализовано бэком, значения приходят подставленными.
+
+- [ ] **Step 1: Подсказка**
+
+В редакторе шаблона (RecordEditor или TemplatesPage, рядом с полями записей) добавь короткую подсказку (FieldDescription / текст), например: «Используйте `{{domain_name}}` в имени или значении — при проверке домена подставится имя его зоны (без завершающей точки).» Стиль — как существующие подсказки на страницах (напр. FieldDescription в AccountsPage). Не добавляй валидацию/трансформацию — плейсхолдер это обычный текст.
+
+- [ ] **Step 2: Тест + прогон**
+
+Тест: подсказка с текстом про `{{domain_name}}` присутствует в отрендеренном редакторе шаблона. Run: `cd web && npm run test -- --run && npx tsc --noEmit && npm run build`.
+```bash
+cd .. && git checkout internal/web/dist/index.html
+git add web/src/
+git commit -m "feat(web): hint about {{domain_name}} placeholder in template editor"
+```
+
+---
+
+## Итоговая проверка
+
+- `go build ./... && go test ./...` — PASS.
+- `cd web && npm run test -- --run && npm run build` — PASS.
+- Ручная: шаблон с `{{domain_name}}` привязать к домену A и B → дифф каждого показывает подстановку имени соответствующей зоны; snapshot зоны создаёт шаблон с `{{domain_name}}` вместо имени зоны; шаблон переиспользуем между доменами.

internal/api/handlers.go

@@ -13,6 +13,7 @@ import (
 	"github.com/vasyakrg/dns-autoresolver/internal/model"
 	"github.com/vasyakrg/dns-autoresolver/internal/service"
 	"github.com/vasyakrg/dns-autoresolver/internal/store/dto"
+	"github.com/vasyakrg/dns-autoresolver/internal/tmpl"
 )
 
 func writeJSON(w http.ResponseWriter, status int, v any) {
@@ -141,17 +142,17 @@ func (a *API) handleTemplateFromZone(w http.ResponseWriter, r *http.Request) {
 			managed = append(managed, rc)
 		}
 	}
-	doc := dto.FromModel(managed)
+	doc := tmpl.Parameterize(managed, dom.ZoneName)
-	tmpl, err := a.Store.CreateTemplate(r.Context(), pid, dom.ZoneName+" snapshot", doc)
+	tpl, err := a.Store.CreateTemplate(r.Context(), pid, dom.ZoneName+" snapshot", doc)
 	if err != nil {
 		log.Printf("api: template-from-zone: create template failed: %v", err)
 		writeErr(w, http.StatusInternalServerError, "internal error")
 		return
 	}
-	if _, err := a.Store.SetDomainTemplate(r.Context(), did, pid, &tmpl.ID); err != nil {
+	if _, err := a.Store.SetDomainTemplate(r.Context(), did, pid, &tpl.ID); err != nil {
 		log.Printf("api: template-from-zone: attach template failed: %v", err)
 		writeErr(w, http.StatusInternalServerError, "internal error")
 		return
 	}
-	writeJSON(w, http.StatusCreated, toTemplateResponse(tmpl))
+	writeJSON(w, http.StatusCreated, toTemplateResponse(tpl))
 }

internal/api/tenant_test.go

@@ -643,15 +643,17 @@ func TestZoneRecords_ReturnsProviderRecords(t *testing.T) {
 
 // TestTemplateFromZone_SnapshotsManagedRecordsOnlyAndAttaches covers the
 // snapshot-to-template flow: NS/SOA are read-only and must be excluded from
-// the generated template, and the new template must be auto-attached to the
+// the generated template, the new template must be auto-attached to the
-// domain (SetDomainTemplate) so check/apply become immediately available.
+// domain (SetDomainTemplate) so check/apply become immediately available,
+// and the zone name must be parameterized to {{domain_name}} in names/values
+// so the resulting template is reusable across domains (tmpl.Parameterize).
 func TestTemplateFromZone_SnapshotsManagedRecordsOnlyAndAttaches(t *testing.T) {
 	a, ts := newTenantTestAPI()
 	domID := uuid.New()
 	ts.domains = []store.Domain{{ID: domID, ZoneName: "example.com", ZoneID: "z1"}}
 	a.Svc = &mockCheckApplier{zoneRecords: []model.Record{
 		{Type: model.A, Name: "a.example.com.", TTL: 300, Values: []string{"1.1.1.1"}},
-		{Type: model.TXT, Name: "a.example.com.", TTL: 300, Values: []string{"v=spf1 -all"}},
+		{Type: model.TXT, Name: "a.example.com.", TTL: 300, Values: []string{"v=spf1 a:mail.example.com -all"}},
 		{Type: model.NS, Name: "example.com.", TTL: 3600, Values: []string{"ns1.example.com."}},
 		{Type: model.SOA, Name: "example.com.", TTL: 3600, Values: []string{"ns1.example.com. admin.example.com. 1 2 3 4 5"}},
 	}}
@@ -674,6 +676,17 @@ func TestTemplateFromZone_SnapshotsManagedRecordsOnlyAndAttaches(t *testing.T) {
 		if r.Type == "NS" || r.Type == "SOA" {
 			t.Fatalf("read-only record type %s leaked into snapshot template", r.Type)
 		}
+		if strings.Contains(r.Name, "example.com") {
+			t.Fatalf("expected zone name parameterized to {{domain_name}} in record name, got %+v", r)
+		}
+		for _, v := range r.Values {
+			if strings.Contains(v, "example.com") {
+				t.Fatalf("expected zone name parameterized to {{domain_name}} in record value, got %+v", r)
+			}
+		}
+	}
+	if ts.createTemplate.Doc.Records[1].Values[0] != "v=spf1 a:mail.{{domain_name}} -all" {
+		t.Fatalf("expected SPF value parameterized, got %q", ts.createTemplate.Doc.Records[1].Values[0])
 	}
 	// SetDomainTemplate must have been called with the newly created template's id.
 	if ts.domains[0].TemplateID == nil || *ts.domains[0].TemplateID != ts.createTemplate.ID {

internal/service/service.go

@@ -13,6 +13,7 @@ import (
 	"github.com/vasyakrg/dns-autoresolver/internal/provider"
 	"github.com/vasyakrg/dns-autoresolver/internal/provider/registry"
 	"github.com/vasyakrg/dns-autoresolver/internal/store/dto"
+	"github.com/vasyakrg/dns-autoresolver/internal/tmpl"
 )
 
 // ErrProviderUnavailable marks failures that happened while talking to the
@@ -25,6 +26,7 @@ var ErrProviderUnavailable = errors.New("service: provider unavailable")
 // DomainRef is the minimal data the service needs about a domain.
 type DomainRef struct {
 	ZoneID    string
+	ZoneName  string
 	Provider  string
 	SecretEnc string
 	Template  dto.TemplateDoc
@@ -84,7 +86,7 @@ func (s *DomainService) resolve(ctx context.Context, projectID, domainID uuid.UU
 	if err != nil {
 		return nil, provider.Credentials{}, ref, diff.Changeset{}, err
 	}
-	cs := diff.Diff(ref.Template.ToModel(), actual)
+	cs := diff.Diff(tmpl.Materialize(ref.Template, ref.ZoneName), actual)
 	return p, creds, ref, cs, nil
 }
 

internal/service/service_test.go

@@ -66,7 +66,7 @@ func setup(t *testing.T, actual []model.Record, tmpl dto.TemplateDoc) (*DomainSe
 	reg.Register(fp)
 	cipher := testCipher(t)
 	enc, _ := cipher.Encrypt([]byte("secret"))
-	loader := fakeLoader{ref: DomainRef{ZoneID: "z1", Provider: "selectel", SecretEnc: enc, Template: tmpl}}
+	loader := fakeLoader{ref: DomainRef{ZoneID: "z1", ZoneName: "example.com.", Provider: "selectel", SecretEnc: enc, Template: tmpl}}
 	return New(loader, nopRecorder{}, reg, cipher), fp
 }
 
@@ -85,6 +85,28 @@ func TestCheckProducesDiff(t *testing.T) {
 	}
 }
 
+// TestCheckMaterializesDomainNamePlaceholder covers the tmpl.Materialize
+// wiring in resolve: a template record using {{domain_name}} in its name and
+// values must be diffed against the zone using the actual zone name (without
+// trailing dot) substituted in, so a template reused across domains reports
+// in-sync rather than spurious add/delete pairs.
+func TestCheckMaterializesDomainNamePlaceholder(t *testing.T) {
+	actual := []model.Record{
+		{Type: model.TXT, Name: "_dmarc.example.com.", TTL: 600, Values: []string{"v=DMARC1; p=quarantine"}},
+	}
+	tmpl := dto.TemplateDoc{Records: []dto.RecordDTO{
+		{Type: "TXT", Name: "_dmarc.{{domain_name}}.", TTL: 600, Values: []string{"v=DMARC1; p=quarantine"}},
+	}}
+	svc, _ := setup(t, actual, tmpl)
+	cs, err := svc.Check(context.Background(), uuid.New(), uuid.New())
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(cs.Updates()) != 0 || len(cs.Prunes()) != 0 {
+		t.Fatalf("expected placeholder materialized against zone name to be in sync, got updates=%+v prunes=%+v", cs.Updates(), cs.Prunes())
+	}
+}
+
 // TestZoneRecordsReadsProviderDirectly covers the no-template zone-viewing
 // path: ZoneRecords must return the provider's live records with no diff
 // and no template involved (loader's Template field is left zero-valued).

internal/store/db/domains.sql.go

@@ -184,7 +184,7 @@ func (q *Queries) ListDomains(ctx context.Context, projectID uuid.UUID) ([]Domai
 }
 
 const loadDomainFull = `-- name: LoadDomainFull :one
-SELECT d.zone_id, a.provider, a.secret_enc, t.doc
+SELECT d.zone_id, d.zone_name, a.provider, a.secret_enc, t.doc
 FROM domains d
 JOIN provider_accounts a ON a.id = d.provider_account_id
 LEFT JOIN templates t ON t.id = d.template_id
@@ -198,6 +198,7 @@ type LoadDomainFullParams struct {
 
 type LoadDomainFullRow struct {
 	ZoneID    string           `json:"zone_id"`
+	ZoneName  string           `json:"zone_name"`
 	Provider  string           `json:"provider"`
 	SecretEnc string           `json:"secret_enc"`
 	Doc       *dto.TemplateDoc `json:"doc"`
@@ -208,6 +209,7 @@ func (q *Queries) LoadDomainFull(ctx context.Context, arg LoadDomainFullParams)
 	var i LoadDomainFullRow
 	err := row.Scan(
 		&i.ZoneID,
+		&i.ZoneName,
 		&i.Provider,
 		&i.SecretEnc,
 		&i.Doc,

internal/store/loader.go

@@ -27,6 +27,7 @@ func (s *Store) LoadDomain(ctx context.Context, projectID, domainID uuid.UUID) (
 	}
 	return service.DomainRef{
 		ZoneID:    row.ZoneID,
+		ZoneName:  row.ZoneName,
 		Provider:  row.Provider,
 		SecretEnc: row.SecretEnc,
 		Template:  *row.Doc,

internal/store/queries/domains.sql

@@ -23,7 +23,7 @@ SELECT * FROM domains WHERE project_id = $1 ORDER BY created_at;
 DELETE FROM domains WHERE id = $1 AND project_id = $2;
 
 -- name: LoadDomainFull :one
-SELECT d.zone_id, a.provider, a.secret_enc, t.doc
+SELECT d.zone_id, d.zone_name, a.provider, a.secret_enc, t.doc
 FROM domains d
 JOIN provider_accounts a ON a.id = d.provider_account_id
 LEFT JOIN templates t ON t.id = d.template_id

internal/tmpl/tmpl.go

@@ -0,0 +1,96 @@
+// Package tmpl renders reusable DNS templates for a concrete zone.
+//
+// A template stores records containing the {{domain_name}} placeholder; it is
+// materialised (placeholder -> zone name, without the trailing dot) just
+// before diff/apply against a specific domain, and parameterised (zone name
+// -> placeholder) when snapshotting a live zone into a reusable template.
+package tmpl
+
+import (
+	"regexp"
+	"strings"
+
+	"github.com/vasyakrg/dns-autoresolver/internal/model"
+	"github.com/vasyakrg/dns-autoresolver/internal/store/dto"
+)
+
+const Placeholder = "{{domain_name}}"
+
+func zoneName(z string) string { return strings.TrimSuffix(z, ".") }
+
+// replaceZoneBoundary replaces occurrences of the zone name matched by re
+// with Placeholder, but only where the match sits on a DNS-label boundary:
+// the zone name must not be a suffix of a longer label. re must be built
+// from zoneBoundaryPattern for a specific zone name. A boundary is the
+// start/end of the string, or any character that cannot appear inside a DNS
+// label (i.e. not a letter, digit, or hyphen — a dot qualifies). This
+// prevents an external host that merely ends with the zone name as a
+// substring (e.g. "notreconops.ru." against zone "reconops.ru") from being
+// falsely parameterized.
+//
+// Replacement runs to a fixed point: a single regexp pass is non-overlapping,
+// so two adjacent zone occurrences separated by a single boundary character
+// (e.g. "reconops.ru.reconops.ru.") would only have the first one matched,
+// since that shared separator is consumed as the first match's right
+// boundary and is unavailable as the second match's left boundary. Placeholder
+// ends in "}", itself a valid boundary character, so re-running the pass
+// against the previous pass's output resolves this without double-counting.
+func replaceZoneBoundary(s string, re *regexp.Regexp) string {
+	for {
+		next := re.ReplaceAllString(s, "${1}"+Placeholder+"${2}")
+		if next == s {
+			return s
+		}
+		s = next
+	}
+}
+
+// zoneBoundaryPattern builds the regexp source used to find z on a
+// DNS-label boundary within a record's Name or Value.
+func zoneBoundaryPattern(z string) string {
+	return `(^|[^a-zA-Z0-9-])` + regexp.QuoteMeta(z) + `([^a-zA-Z0-9-]|$)`
+}
+
+// Materialize renders a template's records for the given zone, substituting
+// {{domain_name}} with the zone name (without the trailing dot) in each
+// record's Name and every Value.
+func Materialize(doc dto.TemplateDoc, zone string) []model.Record {
+	z := zoneName(zone)
+	out := make([]model.Record, 0, len(doc.Records))
+	for _, r := range doc.Records {
+		vals := make([]string, len(r.Values))
+		for i, v := range r.Values {
+			vals[i] = strings.ReplaceAll(v, Placeholder, z)
+		}
+		out = append(out, model.Record{
+			Type:   model.RecordType(r.Type),
+			Name:   strings.ReplaceAll(r.Name, Placeholder, z),
+			TTL:    r.TTL,
+			Values: vals,
+		})
+	}
+	return out
+}
+
+// Parameterize replaces occurrences of the zone name with {{domain_name}} in
+// record names and values, so a snapshot of a live zone becomes portable.
+// Records with no zone-name occurrence (DKIM key, external CNAME target) are
+// left unchanged.
+func Parameterize(recs []model.Record, zone string) dto.TemplateDoc {
+	z := zoneName(zone)
+	re := regexp.MustCompile(zoneBoundaryPattern(z))
+	out := dto.TemplateDoc{Records: make([]dto.RecordDTO, 0, len(recs))}
+	for _, r := range recs {
+		vals := make([]string, len(r.Values))
+		for i, v := range r.Values {
+			vals[i] = replaceZoneBoundary(v, re)
+		}
+		out.Records = append(out.Records, dto.RecordDTO{
+			Type:   string(r.Type),
+			Name:   replaceZoneBoundary(r.Name, re),
+			TTL:    r.TTL,
+			Values: vals,
+		})
+	}
+	return out
+}

internal/tmpl/tmpl_test.go

@@ -0,0 +1,103 @@
+package tmpl_test
+
+import (
+	"testing"
+
+	"github.com/vasyakrg/dns-autoresolver/internal/model"
+	"github.com/vasyakrg/dns-autoresolver/internal/store/dto"
+	"github.com/vasyakrg/dns-autoresolver/internal/tmpl"
+)
+
+func TestMaterializeReplacesInNameAndValues(t *testing.T) {
+	doc := dto.TemplateDoc{Records: []dto.RecordDTO{
+		{Type: "TXT", Name: "_dmarc.{{domain_name}}.", TTL: 600, Values: []string{"v=DMARC1; p=quarantine"}},
+		{Type: "MX", Name: "{{domain_name}}.", TTL: 600, Values: []string{"0 pmg2-mail.{{domain_name}}."}},
+		{Type: "TXT", Name: "{{domain_name}}.", TTL: 600, Values: []string{"v=spf1 a:mail.{{domain_name}} ~all"}},
+	}}
+	recs := tmpl.Materialize(doc, "reconops.ru.") // trailing dot stripped
+	if recs[0].Name != "_dmarc.reconops.ru." {
+		t.Fatalf("name: %q", recs[0].Name)
+	}
+	if recs[1].Values[0] != "0 pmg2-mail.reconops.ru." {
+		t.Fatalf("mx value: %q", recs[1].Values[0])
+	}
+	if recs[2].Values[0] != "v=spf1 a:mail.reconops.ru ~all" {
+		t.Fatalf("spf value: %q", recs[2].Values[0])
+	}
+}
+
+func TestParameterizeIsInverseForZoneOccurrences(t *testing.T) {
+	recs := []model.Record{
+		{Type: "TXT", Name: "_dmarc.reconops.ru.", TTL: 600, Values: []string{"v=DMARC1"}},
+		{Type: "TXT", Name: "reconops.ru.", TTL: 600, Values: []string{"v=spf1 a:mail.reconops.ru ~all"}},
+		{Type: "CNAME", Name: "mail.reconops.ru.", TTL: 600, Values: []string{"amail.amega.kz."}}, // external host untouched
+	}
+	doc := tmpl.Parameterize(recs, "reconops.ru.")
+	if doc.Records[0].Name != "_dmarc.{{domain_name}}." {
+		t.Fatalf("name: %q", doc.Records[0].Name)
+	}
+	if doc.Records[1].Values[0] != "v=spf1 a:mail.{{domain_name}} ~all" {
+		t.Fatalf("spf: %q", doc.Records[1].Values[0])
+	}
+	if doc.Records[2].Values[0] != "amail.amega.kz." {
+		t.Fatalf("external cname value must be untouched: %q", doc.Records[2].Values[0])
+	}
+}
+
+func TestParameterizeDoesNotMatchZoneNameAsSuffixOfLongerLabel(t *testing.T) {
+	recs := []model.Record{
+		{Type: "CNAME", Name: "www.reconops.ru.", TTL: 600, Values: []string{"notreconops.ru."}},
+	}
+	doc := tmpl.Parameterize(recs, "reconops.ru.")
+	if doc.Records[0].Values[0] != "notreconops.ru." {
+		t.Fatalf("external host that merely ends with the zone name must be left untouched: %q", doc.Records[0].Values[0])
+	}
+	if doc.Records[0].Name != "www.{{domain_name}}." {
+		t.Fatalf("name: %q", doc.Records[0].Name)
+	}
+}
+
+func TestParameterizeApexAndSubdomainBoundaries(t *testing.T) {
+	recs := []model.Record{
+		{Type: "A", Name: "reconops.ru.", TTL: 600, Values: []string{"1.2.3.4"}},
+		{Type: "TXT", Name: "_dmarc.reconops.ru.", TTL: 600, Values: []string{"v=DMARC1; p=quarantine"}},
+		{Type: "MX", Name: "reconops.ru.", TTL: 600, Values: []string{"0 pmg2-mail.reconops.ru."}},
+	}
+	doc := tmpl.Parameterize(recs, "reconops.ru.")
+	if doc.Records[0].Name != "{{domain_name}}." {
+		t.Fatalf("apex name: %q", doc.Records[0].Name)
+	}
+	if doc.Records[1].Name != "_dmarc.{{domain_name}}." {
+		t.Fatalf("sub name: %q", doc.Records[1].Name)
+	}
+	if doc.Records[2].Values[0] != "0 pmg2-mail.{{domain_name}}." {
+		t.Fatalf("mx value: %q", doc.Records[2].Values[0])
+	}
+}
+
+func TestParameterizeReplacesAllOccurrencesInSPFRecord(t *testing.T) {
+	recs := []model.Record{
+		{Type: "TXT", Name: "reconops.ru.", TTL: 600, Values: []string{"v=spf1 a:mail.reconops.ru a:pmg2-mail.reconops.ru ~all"}},
+	}
+	doc := tmpl.Parameterize(recs, "reconops.ru.")
+	want := "v=spf1 a:mail.{{domain_name}} a:pmg2-mail.{{domain_name}} ~all"
+	if doc.Records[0].Values[0] != want {
+		t.Fatalf("spf: got %q, want %q", doc.Records[0].Values[0], want)
+	}
+}
+
+func TestParameterizeReplacesAdjacentZoneOccurrencesSharingASingleBoundary(t *testing.T) {
+	// Two zone-name occurrences separated by exactly one boundary character
+	// (the dot). A single non-overlapping regexp pass would only catch the
+	// first occurrence, since the shared "." is consumed as its right
+	// boundary and is then unavailable as the second occurrence's left
+	// boundary. replaceZoneBoundary must still resolve both.
+	recs := []model.Record{
+		{Type: "TXT", Name: "reconops.ru.", TTL: 600, Values: []string{"reconops.ru.reconops.ru."}},
+	}
+	doc := tmpl.Parameterize(recs, "reconops.ru.")
+	want := "{{domain_name}}.{{domain_name}}."
+	if doc.Records[0].Values[0] != want {
+		t.Fatalf("adjacent occurrences: got %q, want %q", doc.Records[0].Values[0], want)
+	}
+}

web/src/components/RecordEditor.test.tsx

@@ -126,6 +126,12 @@ test("удаление записи вызывает onChange без удалё
   ])
 })
 
+test("подсказка про плейсхолдер {{domain_name}} отображается в редакторе", () => {
+  render(<Harness initial={[]} onChange={vi.fn()} />)
+
+  expect(screen.getByText(/\{\{domain_name\}\}/)).toBeInTheDocument()
+})
+
 test("mono-шрифт применён к полям name и values", () => {
   render(
     <Harness

web/src/components/RecordEditor.tsx

@@ -1,7 +1,8 @@
-import { Plus, Trash2 } from "lucide-react"
+import { Info, Plus, Trash2 } from "lucide-react"
 import { Button } from "@/components/ui/button"
 import { Input } from "@/components/ui/input"
 import { Textarea } from "@/components/ui/textarea"
+import { FieldDescription } from "@/components/ui/field"
 import {
   Select,
   SelectContent,
@@ -42,6 +43,15 @@ export function RecordEditor({
 
   return (
     <div className="flex flex-col gap-2">
+      <FieldDescription className="flex items-start gap-2 rounded-lg border border-border/60 bg-background/40 px-3 py-2.5">
+        <Info className="mt-0.5 size-3.5 shrink-0 text-muted-foreground" strokeWidth={1.75} />
+        <span>
+          Используйте <code className="font-dns text-foreground">{"{{domain_name}}"}</code> в имени
+          или значении записи — при проверке домена подставится имя его зоны (без завершающей
+          точки).
+        </span>
+      </FieldDescription>
+
       {value.map((record, index) => (
         <div
           key={index}