Honor coordinator lease retry timing

Author: chubes4

packages/runtime-cloudflare/src/lease-retry.ts

@@ -0,0 +1,8 @@
+const DEFAULT_RETRY_DELAY_MS = 1_000
+
+export function leaseRetryDelayMs(retryAfterSeconds: number | undefined, remainingMs: number): number {
+  const requestedMs = retryAfterSeconds !== undefined && Number.isFinite(retryAfterSeconds) && retryAfterSeconds > 0
+    ? retryAfterSeconds * 1_000
+    : DEFAULT_RETRY_DELAY_MS
+  return Math.max(0, Math.min(remainingMs, requestedMs))
+}

packages/runtime-cloudflare/src/worker.ts

@@ -6,6 +6,7 @@ import { bootWordPressAndRequestHandler, type WordPressInstallMode } from "@wp-p
 import { dependenciesTotalSize, init } from "../../../node_modules/@php-wasm/web-8-5/asyncify/php_8_5.js"
 import phpWasmModule from "../../../node_modules/@php-wasm/web-8-5/asyncify/8_5_8/php_8_5.wasm"
 import { CLOUDFLARE_RUNTIME_HEALTH_MARKER, CLOUDFLARE_RUNTIME_HEALTH_SCHEMA, cloudflareRuntimeHealthResponse } from "./health-envelope.js"
+import { leaseRetryDelayMs } from "./lease-retry.js"
 import { routeWorkerRequest } from "./request-routing.js"
 import { toFetchResponse, toPHPRequest } from "./request-translation.js"
 import { deriveWordPressAuthConstants, type WordPressAuthConstant } from "./wordpress-auth.js"
@@ -228,13 +229,15 @@ async function coordinatorCall<T>(coordinator: DurableObjectStub, requestUrl: st
 async function acquireLease(coordinator: DurableObjectStub, requestUrl: string): Promise<Lease> {
   const deadline = Date.now() + LEASE_ACQUISITION_TIMEOUT_MS
   let lastError: CoordinatorRequestError | undefined
-  while (Date.now() < deadline) {
+  while (true) {
+    const remainingMs = deadline - Date.now()
+    if (remainingMs <= 0) break
     try {
       return await coordinatorCall<Lease>(coordinator, requestUrl, "begin", {})
     } catch (error) {
       if (!(error instanceof CoordinatorRequestError) || error.status !== 409) throw error
       lastError = error
-      await new Promise((resolve) => setTimeout(resolve, Math.min(250, Math.max(25, (error.retryAfter ?? 1) * 100))))
+      await new Promise((resolve) => setTimeout(resolve, leaseRetryDelayMs(error.retryAfter, deadline - Date.now())))
     }
   }
   throw new Error(`Timed out waiting for the canonical WordPress lease${lastError ? `: ${lastError.message}` : "."}`)

tests/cloudflare-runtime.test.ts

@@ -7,6 +7,7 @@ import test from "node:test"
 import { decodeZip, encodeZip } from "@php-wasm/stream-compression"
 import { RUNTIME_COMMAND_RESULT_SCHEMA } from "../packages/runtime-core/src/runtime-contracts.js"
 import { CLOUDFLARE_RUNTIME_HEALTH_MARKER, CLOUDFLARE_RUNTIME_HEALTH_SCHEMA, cloudflareRuntimeHealthResponse } from "../packages/runtime-cloudflare/src/health-envelope.js"
+import { leaseRetryDelayMs } from "../packages/runtime-cloudflare/src/lease-retry.js"
 import { routeWorkerRequest } from "../packages/runtime-cloudflare/src/request-routing.js"
 import { toFetchResponse, toPHPRequest } from "../packages/runtime-cloudflare/src/request-translation.js"
 import { WordPressStateCoordinator } from "../packages/runtime-cloudflare/src/state-coordinator.js"
@@ -106,6 +107,13 @@ test("Cloudflare runtime declares the paid-plan WordPress boot CPU budget", asyn
   assert.equal(config.limits?.cpu_ms, 300_000)
 })
 
+test("Cloudflare lease contention honors Retry-After without exceeding the acquisition deadline", () => {
+  assert.equal(leaseRetryDelayMs(90, 100_000), 90_000)
+  assert.equal(leaseRetryDelayMs(90, 12_345), 12_345)
+  assert.equal(leaseRetryDelayMs(undefined, 100_000), 1_000)
+  assert.equal(leaseRetryDelayMs(Number.NaN, 500), 500)
+})
+
 test("Cloudflare runtime packages a provenanced canonical MDI seed", async () => {
   const config = JSON.parse((await readFile(new URL("../packages/runtime-cloudflare/wrangler.jsonc", import.meta.url), "utf8")).replace(/^\s*\/\/.*\n/, "")) as {
     rules?: Array<{ type?: string; globs?: string[] }>