feat(services): крутить weighted как доли времени на одном IP

Веса задают долю слотов на общем FQDN (1 к 3 = ¼ и ¾ цикла), TTL 60.
В селекте режима показывать текстовое имя, не ID.

Co-authored-by: Cursor <[email protected]>

apps/api/src/app.ts

@@ -38,6 +38,10 @@ import {
   healthEngineFallbacksFromConfig,
   scheduleHealthCheckJob,
 } from "./services/health-check-scheduler.js";
+import {
+  createWeightedDnsTask,
+  scheduleWeightedDnsJob,
+} from "./services/weighted-dns-scheduler.js";
 import { fireEnsureHealthWorker } from "./services/health/health-worker-deploy.js";
 import { AsyncTask, CronJob } from "toad-scheduler";
 
@@ -133,6 +137,7 @@ export async function buildApp(opts: BuildAppOptions = {}) {
     app.decorate("reloadHealthCheckJob", () => {
       scheduleHealthCheckJob(app, config, healthTask);
     });
+    scheduleWeightedDnsJob(app, createWeightedDnsTask(app));
     if (config.cloudflareApiToken) {
       fireEnsureHealthWorker(
         app.db,

apps/api/src/services/routing/index.ts

@@ -2,25 +2,30 @@ import type { LbMode } from "@cfdm/shared";
 import { failoverDesired } from "./failover.js";
 import { roundRobinDesired } from "./round-robin.js";
 import type { LbIpRow, LbTargetConfig } from "./types.js";
+import { weightedDesired } from "./weighted.js";
 
 export type { LbIpRow, LbTargetConfig } from "./types.js";
 export { isHealthy } from "./health.js";
 export { withBindingLock } from "./binding-lock.js";
+export { WEIGHTED_DNS_TTL, WEIGHTED_SLOT_MS, weightedDesired } from "./weighted.js";
 
 export function selectActiveIpsByMode(
   config: LbTargetConfig,
   rows: LbIpRow[],
+  nowMs = Date.now(),
 ): string[] {
   if (rows.length === 0) return [];
   if (config.lb_mode === "failover") {
     return failoverDesired(rows);
   }
-  // weighted = round_robin on DNS (one A per IP)
+  if (config.lb_mode === "weighted") {
+    return weightedDesired(rows, nowMs);
+  }
   return roundRobinDesired(rows);
 }
 
 export function strategyLabel(mode: LbMode): string {
   if (mode === "failover") return "Failover";
-  if (mode === "weighted") return "Round Robin (weighted alias)";
+  if (mode === "weighted") return "Weighted";
   return "Round Robin";
 }

apps/api/src/services/routing/weighted.ts

@@ -0,0 +1,24 @@
+import type { LbIpRow } from "./types.js";
+import { isHealthy } from "./health.js";
+
+/** Slot length for time-sliced weighted DNS (one A at a time). */
+export const WEIGHTED_SLOT_MS = 60_000;
+
+/** Cloudflare DNS-only minimum TTL; Auto (1) is ~300s and would smear ratios. */
+export const WEIGHTED_DNS_TTL = 60;
+
+export function weightedDesired(rows: LbIpRow[], nowMs = Date.now()): string[] {
+  if (rows.length === 0) return [];
+  const healthy = rows.filter((r) => isHealthy(r.health));
+  const pool = healthy.length > 0 ? healthy : rows;
+  if (pool.length === 1) return [pool[0]!.ip];
+
+  const sorted = [...pool].sort((a, b) => a.ip.localeCompare(b.ip));
+  const cycle: string[] = [];
+  for (const row of sorted) {
+    const weight = Math.max(1, Math.round(row.weight));
+    for (let i = 0; i < weight; i++) cycle.push(row.ip);
+  }
+  const slot = Math.floor(nowMs / WEIGHTED_SLOT_MS) % cycle.length;
+  return [cycle[slot]!];
+}

apps/api/src/services/service-config-service.ts

@@ -32,6 +32,7 @@ import {
   isHealthy,
   selectActiveIpsByMode,
   withBindingLock,
+  WEIGHTED_DNS_TTL,
   type LbIpRow,
   type LbTargetConfig,
 } from "./routing/index.js";
@@ -39,6 +40,12 @@ import {
 export type { LbIpRow, LbTargetConfig };
 export { selectActiveIpsByMode };
 
+const AUTO_DNS_TTL = 1;
+
+function ttlForLbMode(mode: LbMode): number {
+  return mode === "weighted" ? WEIGHTED_DNS_TTL : AUTO_DNS_TTL;
+}
+
 export function failoverARecordDiff(
   existingA: readonly string[],
   desiredIps: readonly string[],
@@ -276,6 +283,23 @@ function computeActiveIps(
   return selectActiveIpsByMode(state.config, state.rows);
 }
 
+function desiredAIps(
+  db: Db,
+  scope: HealthCheckScope,
+  refId: number,
+  fallbackIps: string[],
+): string[] {
+  const config =
+    scope === "binding"
+      ? getBindingLbState(db, refId).config
+      : getGroupLbState(db, refId).config;
+  if (config.lb_mode === "weighted" || config.health_check_enabled) {
+    const activeIps = computeActiveIps(db, scope, refId);
+    if (activeIps.length > 0) return activeIps;
+  }
+  return fallbackIps;
+}
+
 async function collectKnownZones(
   db: Db,
   cf: CloudflareClient,
@@ -613,7 +637,16 @@ async function syncBindingDns(
     return;
   }
 
-  await syncBindingADns(db, cf, bindingId, domainId, hostname, desiredIps);
+  const binding = repos.getBinding(db, bindingId);
+  await syncBindingADns(
+    db,
+    cf,
+    bindingId,
+    domainId,
+    hostname,
+    desiredIps,
+    ttlForLbMode(binding.lb_mode),
+  );
 }
 
 async function syncBindingCnameDns(
@@ -700,6 +733,7 @@ async function syncBindingADns(
   domainId: number,
   hostname: string,
   desiredIps: string[],
+  ttl: number,
 ): Promise<void> {
   const domain = repos.getDomain(db, domainId);
   const zoneName = domain.zone_name;
@@ -735,13 +769,15 @@ async function syncBindingADns(
 
   for (const ip of desiredIps) {
     const existing = refreshed.find((r) => r.content === ip);
+    const recordName = dnsNameForBinding(hostname, zoneName);
     let recordId: number;
     if (existing) {
-      if (!dnsRecordNamesMatch(existing.name, hostname, zoneName)) {
+      if (!dnsRecordNamesMatch(existing.name, hostname, zoneName) || existing.ttl !== ttl) {
         await dnsService.update(db, cf, domainId, existing.id, {
           record_type: "A",
-          name: dnsNameForBinding(hostname, zoneName),
+          name: recordName,
           content: ip,
+          ttl,
           proxied: false,
         });
       }
@@ -759,12 +795,24 @@ async function syncBindingADns(
       if (adopted) {
         repos.linkBindingRecord(db, bindingId, adopted.id);
         recordId = adopted.id;
+        if (
+          !dnsRecordNamesMatch(adopted.name, hostname, zoneName) ||
+          adopted.ttl !== ttl
+        ) {
+          await dnsService.update(db, cf, domainId, adopted.id, {
+            record_type: "A",
+            name: recordName,
+            content: ip,
+            ttl,
+            proxied: false,
+          });
+        }
       } else {
         const record = await dnsService.create(db, cf, domainId, {
           record_type: "A",
-          name: dnsNameForBinding(hostname, zoneName),
+          name: recordName,
           content: ip,
-          ttl: 1,
+          ttl,
           proxied: false,
         });
         repos.linkBindingRecord(db, bindingId, record.id);
@@ -1001,12 +1049,7 @@ async function syncServiceBindingsToDns(
     }
     validateTargetIpsInPool(targetIps, ips);
 
-    if (binding.health_check_enabled) {
-      const activeIps = computeActiveIps(db, "binding", binding.id);
-      if (activeIps.length > 0) {
-        targetIps = activeIps;
-      }
-    }
+    const desiredIps = desiredAIps(db, "binding", binding.id, targetIps);
 
     await syncBindingDns(
       db,
@@ -1014,7 +1057,7 @@ async function syncServiceBindingsToDns(
       binding.id,
       binding.domain_id,
       binding.hostname,
-      targetIps,
+      desiredIps,
       null,
     );
   }
@@ -1046,6 +1089,7 @@ async function syncGroupDomainDnsRecords(
   domainId: number,
   hostname: string,
   desiredIps: string[],
+  ttl: number = AUTO_DNS_TTL,
 ): Promise<void> {
   const domain = repos.getDomain(db, domainId);
   const zoneName = domain.zone_name;
@@ -1061,14 +1105,16 @@ async function syncGroupDomainDnsRecords(
   if (desiredIps.length === 0) return;
 
   const refreshed = repos.listGroupDnsRecords(db, groupId);
+  const recordName = dnsNameForBinding(hostname, zoneName);
   for (const ip of desiredIps) {
     const existing = refreshed.find((r) => r.content === ip);
     if (existing) {
-      if (!dnsRecordNamesMatch(existing.name, hostname, zoneName)) {
+      if (!dnsRecordNamesMatch(existing.name, hostname, zoneName) || existing.ttl !== ttl) {
         await dnsService.update(db, cf, domainId, existing.id, {
           record_type: "A",
-          name: dnsNameForBinding(hostname, zoneName),
+          name: recordName,
           content: ip,
+          ttl,
           proxied: false,
         });
       }
@@ -1084,13 +1130,25 @@ async function syncGroupDomainDnsRecords(
     );
     if (adopted) {
       repos.linkGroupDnsRecord(db, groupId, adopted.id);
+      if (
+        !dnsRecordNamesMatch(adopted.name, hostname, zoneName) ||
+        adopted.ttl !== ttl
+      ) {
+        await dnsService.update(db, cf, domainId, adopted.id, {
+          record_type: "A",
+          name: recordName,
+          content: ip,
+          ttl,
+          proxied: false,
+        });
+      }
       continue;
     }
     const record = await dnsService.create(db, cf, domainId, {
       record_type: "A",
-      name: dnsNameForBinding(hostname, zoneName),
+      name: recordName,
       content: ip,
-      ttl: 1,
+      ttl,
       proxied: false,
     });
     repos.linkGroupDnsRecord(db, groupId, record.id);
@@ -1141,9 +1199,8 @@ async function syncGroupDomainDns(
   const knownZones = await collectKnownZones(db, cf);
   const { zoneName, hostname } = parseFqdn(domainValue, knownZones);
   const domainId = await resolveDomainId(db, cf, zoneName);
-  const desiredIps = group.health_check_enabled
-    ? computeActiveIps(db, "group", groupId)
-    : await collectGroupDnsIps(db, groupId);
+  const fallbackIps = await collectGroupDnsIps(db, groupId);
+  const desiredIps = desiredAIps(db, "group", groupId, fallbackIps);
   await syncGroupDomainDnsRecords(
     db,
     cf,
@@ -1151,6 +1208,7 @@ async function syncGroupDomainDns(
     domainId,
     hostname,
     desiredIps,
+    ttlForLbMode(group.lb_mode),
   );
 }
 
@@ -1331,14 +1389,7 @@ export async function updateConfig(
       }
 
       if (pushDns) {
-        let effectiveIps = targetIps;
-        const refreshedBinding = repos.getBinding(db, binding.id);
-        if (refreshedBinding.health_check_enabled) {
-          const activeIps = computeActiveIps(db, "binding", binding.id);
-          if (activeIps.length > 0) {
-            effectiveIps = activeIps;
-          }
-        }
+        const effectiveIps = desiredAIps(db, "binding", binding.id, targetIps);
         await syncBindingDns(
           db,
           cf,
@@ -1644,7 +1695,7 @@ export async function reconcileDnsForTarget(
   if (scope === "binding") {
     await withBindingLock(refId, async () => {
       const binding = repos.getBinding(db, refId);
-      if (!binding.health_check_enabled) return;
+      if (!binding.health_check_enabled && binding.lb_mode !== "weighted") return;
       const service = repos.getService(db, binding.service_id);
       if (!shouldPushDns(db, service)) return;
       const cnameTarget = binding.cname_target?.trim() || null;
@@ -1652,8 +1703,7 @@ export async function reconcileDnsForTarget(
       const ips = repos.listServiceIps(db, service.id);
       const targetIps = repos.listBindingIps(db, binding.id);
       validateTargetIpsInPool(targetIps, ips);
-      const activeIps = computeActiveIps(db, "binding", refId);
-      const desiredIps = activeIps.length > 0 ? activeIps : targetIps;
+      const desiredIps = desiredAIps(db, "binding", refId, targetIps);
       await syncBindingDns(
         db,
         cf,
@@ -1668,8 +1718,59 @@ export async function reconcileDnsForTarget(
   }
 
   const group = repos.getServiceGroup(db, refId);
-  if (!group.enabled || !group.domain?.trim() || !group.health_check_enabled) {
+  if (!group.enabled || !group.domain?.trim()) {
+    return;
+  }
+  if (!group.health_check_enabled && group.lb_mode !== "weighted") {
     return;
   }
   await syncGroupDomainDns(db, cf, refId);
 }
+
+export async function reconcileWeightedDns(
+  db: Db,
+  cf: CloudflareClient,
+): Promise<number> {
+  let n = 0;
+  for (const binding of repos.listAllBindings(db)) {
+    if (binding.lb_mode !== "weighted") continue;
+    if (binding.cname_target?.trim()) continue;
+    try {
+      await withBindingLock(binding.id, async () => {
+        const latest = repos.getBinding(db, binding.id);
+        if (latest.lb_mode !== "weighted") return;
+        if (latest.cname_target?.trim()) return;
+        const service = repos.getService(db, latest.service_id);
+        if (!shouldPushDns(db, service)) return;
+        const targetIps = repos.listBindingIps(db, latest.id);
+        if (targetIps.length === 0) return;
+        const ips = repos.listServiceIps(db, service.id);
+        validateTargetIpsInPool(targetIps, ips);
+        const desiredIps = desiredAIps(db, "binding", latest.id, targetIps);
+        await syncBindingDns(
+          db,
+          cf,
+          latest.id,
+          latest.domain_id,
+          latest.hostname,
+          desiredIps,
+          null,
+        );
+        n += 1;
+      });
+    } catch {
+      continue;
+    }
+  }
+  for (const group of repos.listServiceGroups(db)) {
+    if (group.lb_mode !== "weighted") continue;
+    if (!group.enabled || !group.domain?.trim()) continue;
+    try {
+      await syncGroupDomainDns(db, cf, group.id);
+      n += 1;
+    } catch {
+      continue;
+    }
+  }
+  return n;
+}

apps/api/src/services/weighted-dns-scheduler.ts

@@ -0,0 +1,39 @@
+import type { FastifyInstance } from "fastify";
+import { AsyncTask, SimpleIntervalJob } from "toad-scheduler";
+import * as serviceConfigService from "./service-config-service.js";
+import { WEIGHTED_SLOT_MS } from "./routing/weighted.js";
+
+export const WEIGHTED_DNS_JOB_ID = "weighted-dns";
+
+export function createWeightedDnsTask(app: FastifyInstance): AsyncTask {
+  return new AsyncTask(
+    WEIGHTED_DNS_JOB_ID,
+    async () => {
+      const n = await serviceConfigService.reconcileWeightedDns(app.db, app.cf);
+      if (n > 0) {
+        app.log.info({ reconciled: n }, "weighted dns rotated");
+      }
+    },
+    (err) => {
+      app.log.warn({ err }, "weighted dns rotate failed");
+    },
+  );
+}
+
+export function scheduleWeightedDnsJob(
+  app: FastifyInstance,
+  task: AsyncTask,
+): void {
+  const scheduler = app.scheduler;
+  if (!scheduler) return;
+  if (scheduler.existsById(WEIGHTED_DNS_JOB_ID)) {
+    scheduler.removeById(WEIGHTED_DNS_JOB_ID);
+  }
+  scheduler.addSimpleIntervalJob(
+    new SimpleIntervalJob(
+      { seconds: WEIGHTED_SLOT_MS / 1000, runImmediately: true },
+      task,
+      { id: WEIGHTED_DNS_JOB_ID, preventOverrun: true },
+    ),
+  );
+}