chore: refactoring and tests (#12629)

packages/app/src/utils/server-health.test.ts

@@ -1,6 +1,12 @@
 import { describe, expect, test } from "bun:test"
 import { checkServerHealth } from "./server-health"
 
+function abortFromInput(input: RequestInfo | URL, init?: RequestInit) {
+  if (init?.signal) return init.signal
+  if (input instanceof Request) return input.signal
+  return undefined
+}
+
 describe("checkServerHealth", () => {
   test("returns healthy response with version", async () => {
     const fetch = (async () =>
@@ -24,10 +30,40 @@ describe("checkServerHealth", () => {
     expect(result).toEqual({ healthy: false })
   })
 
+  test("uses timeout fallback when AbortSignal.timeout is unavailable", async () => {
+    const timeout = Object.getOwnPropertyDescriptor(AbortSignal, "timeout")
+    Object.defineProperty(AbortSignal, "timeout", {
+      configurable: true,
+      value: undefined,
+    })
+
+    let aborted = false
+    const fetch = ((input: RequestInfo | URL, init?: RequestInit) =>
+      new Promise<Response>((_resolve, reject) => {
+        const signal = abortFromInput(input, init)
+        signal?.addEventListener(
+          "abort",
+          () => {
+            aborted = true
+            reject(new DOMException("Aborted", "AbortError"))
+          },
+          { once: true },
+        )
+      })) as unknown as typeof globalThis.fetch
+
+    const result = await checkServerHealth("http://localhost:4096", fetch, { timeoutMs: 10 }).finally(() => {
+      if (timeout) Object.defineProperty(AbortSignal, "timeout", timeout)
+      if (!timeout) Reflect.deleteProperty(AbortSignal, "timeout")
+    })
+
+    expect(aborted).toBe(true)
+    expect(result).toEqual({ healthy: false })
+  })
+
   test("uses provided abort signal", async () => {
     let signal: AbortSignal | undefined
     const fetch = (async (input: RequestInfo | URL, init?: RequestInit) => {
-      signal = init?.signal ?? (input instanceof Request ? input.signal : undefined)
+      signal = abortFromInput(input, init)
       return new Response(JSON.stringify({ healthy: true, version: "1.2.3" }), {
         status: 200,
         headers: { "content-type": "application/json" },
@@ -39,4 +75,40 @@ describe("checkServerHealth", () => {
 
     expect(signal).toBe(abort.signal)
   })
+
+  test("retries transient failures and eventually succeeds", async () => {
+    let count = 0
+    const fetch = (async () => {
+      count += 1
+      if (count < 3) throw new TypeError("network")
+      return new Response(JSON.stringify({ healthy: true, version: "1.2.3" }), {
+        status: 200,
+        headers: { "content-type": "application/json" },
+      })
+    }) as unknown as typeof globalThis.fetch
+
+    const result = await checkServerHealth("http://localhost:4096", fetch, {
+      retryCount: 2,
+      retryDelayMs: 1,
+    })
+
+    expect(count).toBe(3)
+    expect(result).toEqual({ healthy: true, version: "1.2.3" })
+  })
+
+  test("returns unhealthy when retries are exhausted", async () => {
+    let count = 0
+    const fetch = (async () => {
+      count += 1
+      throw new TypeError("network")
+    }) as unknown as typeof globalThis.fetch
+
+    const result = await checkServerHealth("http://localhost:4096", fetch, {
+      retryCount: 2,
+      retryDelayMs: 1,
+    })
+
+    expect(count).toBe(3)
+    expect(result).toEqual({ healthy: false })
+  })
 })