fix(preview): bound startup readiness

packages/runtime-playground/src/external-http-load.ts

@@ -33,6 +33,37 @@ export interface RuntimeExternalHttpLoadSample {
   errorCode?: "fetch-failed" | "response-read-failed"
 }
 
+const RUNTIME_PREVIEW_READINESS_TIMEOUT_MS = 10_000
+const RUNTIME_PREVIEW_READINESS_MAX_REDIRECTS = 3
+
+export async function waitForRuntimePreviewReady(runtimeBaseUrl: string): Promise<void> {
+  const origin = new URL(runtimeBaseUrl)
+  let readinessUrl = new URL("/", origin)
+  const signal = AbortSignal.timeout(RUNTIME_PREVIEW_READINESS_TIMEOUT_MS)
+
+  for (let redirectCount = 0; redirectCount <= RUNTIME_PREVIEW_READINESS_MAX_REDIRECTS; redirectCount++) {
+    const response = await fetch(readinessUrl, { redirect: "manual", signal })
+    await response.arrayBuffer()
+    if (response.status < 300 || response.status >= 400) {
+      if (!response.ok) {
+        throw new Error(`runtime preview readiness returned HTTP ${response.status}`)
+      }
+      return
+    }
+
+    const location = response.headers.get("location")
+    if (!location) {
+      throw new Error("runtime preview readiness redirect is missing Location")
+    }
+    readinessUrl = new URL(location, readinessUrl)
+    if (readinessUrl.origin !== origin.origin) {
+      throw new Error("runtime preview readiness redirect leaves the preview origin")
+    }
+  }
+
+  throw new Error(`runtime preview readiness exceeded ${RUNTIME_PREVIEW_READINESS_MAX_REDIRECTS} same-origin redirects`)
+}
+
 export async function runRuntimeExternalHttpLoad(action: Record<string, unknown>, runtimeBaseUrl?: string): Promise<RuntimeExternalHttpLoadResult> {
   if (!runtimeBaseUrl) {
     throw new Error("external_http_load requires an active runtime preview origin")

packages/runtime-playground/src/wordpress-command-runners.ts

@@ -56,7 +56,7 @@ import type { PlaygroundCliServer } from "./preview-server.js"
 import { persistCorePhpunitResult, persistPluginPhpunitCompletedResult, persistPluginPhpunitResult, persistVfsDiagnosticFileToHost, readCorePhpunitDiagnostic, readPluginPhpunitCompletedResult, readPluginPhpunitDiagnostic, readPluginPhpunitDiscoveryResult } from "./runtime-diagnostics.js"
 import { phpunitExecutionSemantics, requiresManagedMysqlMultisitePreinstall } from "./phpunit-command-semantics.js"
 import { parsePhpunitOutput } from "./phpunit-test-results.js"
-import { runRuntimeExternalHttpLoad, type RuntimeExternalHttpLoadResult } from "./external-http-load.js"
+import { runRuntimeExternalHttpLoad, waitForRuntimePreviewReady, type RuntimeExternalHttpLoadResult } from "./external-http-load.js"
 import type { RuntimeWpCliBridge } from "./runtime-wp-cli-bridge.js"
 import { COMMAND_DIAGNOSTICS_ARTIFACT_SCHEMA, PERFORMANCE_OBSERVATION_SCHEMA, commandDiagnosticsCaptureArgs, commandDiagnosticsCaptureSpecFromArgs, createRuntimeCommandResultEnvelope, redactJsonValue, type ExecutionSpec, type MountSpec, type PerformanceObservation, type RuntimeCommandResultEnvelope, type RuntimeCreateSpec, type RuntimeEpisodeTraceRef } from "@automattic/wp-codebox-core"
 import { wordpressUserSessionFromCommandArgs } from "./wordpress-user-sessions.js"
@@ -1176,6 +1176,9 @@ async function benchMergeExternalHttpLoadResults(
     return text
   }
 
+  // Playground's one-time auto-login redirect belongs to startup, not a measured sample.
+  await waitForRuntimePreviewReady(options.baseUrl)
+
   const results = JSON.parse(text) as { schema?: string; scenarios?: Array<Record<string, any>>; provenance?: Record<string, any> }
   if (results.schema !== "wp-codebox/bench-results/v1" || !Array.isArray(results.scenarios)) {
     throw new Error("external-http-load could not merge into an invalid wordpress.bench result")

tests/external-http-load.test.ts

@@ -1,6 +1,6 @@
 import assert from "node:assert/strict"
 import { createServer } from "node:http"
-import { runRuntimeExternalHttpLoad } from "../packages/runtime-playground/src/external-http-load.ts"
+import { runRuntimeExternalHttpLoad, waitForRuntimePreviewReady } from "../packages/runtime-playground/src/external-http-load.ts"
 
 let activeRequests = 0
 let maxActiveRequests = 0
@@ -9,6 +9,7 @@ let receivedMethod = ""
 let receivedBody = ""
 let receivedSecret = ""
 let redirectTargetRequests = 0
+let readinessRequests = 0
 
 const redirectTarget = createServer((_request, response) => {
   redirectTargetRequests++
@@ -18,7 +19,23 @@ await listen(redirectTarget)
 const redirectTargetAddress = redirectTarget.address()
 assert.ok(redirectTargetAddress && typeof redirectTargetAddress === "object")
 
+const readinessRedirector = createServer((_request, response) => {
+  response.writeHead(302, { location: `http://127.0.0.1:${redirectTargetAddress.port}/outside` }).end()
+})
+await listen(readinessRedirector)
+const readinessRedirectorAddress = readinessRedirector.address()
+assert.ok(readinessRedirectorAddress && typeof readinessRedirectorAddress === "object")
+
 const runtime = createServer(async (request, response) => {
+  if (request.url === "/") {
+    readinessRequests++
+    if (readinessRequests === 1) {
+      response.writeHead(302, { location: "/" }).end()
+      return
+    }
+    response.writeHead(204).end()
+    return
+  }
   if (request.url === "/broken") {
     response.destroy()
     return
@@ -51,6 +68,11 @@ assert.ok(runtimeAddress && typeof runtimeAddress === "object")
 const runtimeUrl = `http://127.0.0.1:${runtimeAddress.port}`
 
 try {
+  await waitForRuntimePreviewReady(runtimeUrl)
+  assert.equal(readinessRequests, 2)
+  await assert.rejects(waitForRuntimePreviewReady(`http://127.0.0.1:${readinessRedirectorAddress.port}`), /leaves the preview origin/)
+  assert.equal(redirectTargetRequests, 0)
+
   const matched = await runRuntimeExternalHttpLoad({
     url: "/matched",
     method: "POST",
@@ -124,6 +146,7 @@ try {
   assert.equal(redirectTargetRequests, 0)
 } finally {
   await close(runtime)
+  await close(readinessRedirector)
   await close(redirectTarget)
 }