| 1 | import assert from "node:assert/strict"; |
| 2 | import { test } from "node:test"; |
| 3 | |
| 4 | import { RETRY_WAITS_MS, forward } from "./forward.ts"; |
| 5 | |
| 6 | /** A fetch that throws `failures` times, then answers 200; it counts its calls. */ |
| 7 | function flaky(failures: number) { |
| 8 | const calls: Request[] = []; |
| 9 | const send = async (request: Request) => { |
| 10 | calls.push(request); |
| 11 | if (calls.length <= failures) throw new Error("Network connection lost."); |
| 12 | return new Response("ok"); |
| 13 | }; |
| 14 | return { calls, send }; |
| 15 | } |
| 16 | |
| 17 | const waits: number[] = []; |
| 18 | const sleep = async (ms: number) => { |
| 19 | waits.push(ms); |
| 20 | }; |
| 21 | |
| 22 | test("a GET that fails is tried again, and its answer comes back", async () => { |
| 23 | waits.length = 0; |
| 24 | const { calls, send } = flaky(2); |
| 25 | const response = await forward(new Request("https://registry.npmjs.org/react"), send, sleep); |
| 26 | assert.equal(response.status, 200); |
| 27 | assert.equal(await response.text(), "ok"); |
| 28 | assert.equal(calls.length, 3); |
| 29 | assert.deepEqual(waits, [...RETRY_WAITS_MS]); |
| 30 | }); |
| 31 | |
| 32 | test("one that keeps failing gets a 502 naming the host and why, never a throw", async () => { |
| 33 | const { calls, send } = flaky(10); |
| 34 | const response = await forward(new Request("https://Registry.npmjs.org:443/react"), send, sleep); |
| 35 | assert.equal(calls.length, 3); |
| 36 | assert.equal(response.status, 502); |
| 37 | assert.equal(response.headers.get("x-g1t-egress"), "upstream-failed"); |
| 38 | assert.match(response.headers.get("content-type") ?? "", /^text\/plain/); |
| 39 | const body = await response.text(); |
| 40 | assert.match(body, /registry\.npmjs\.org could not be reached/); |
| 41 | assert.match(body, /Network connection lost\./); |
| 42 | }); |
| 43 | |
| 44 | test("a POST is never sent twice", async () => { |
| 45 | const { calls, send } = flaky(1); |
| 46 | const response = await forward(new Request("https://api.example.com/upload", { method: "POST", body: "data" }), send, sleep); |
| 47 | assert.equal(calls.length, 1); |
| 48 | assert.equal(response.status, 502); |
| 49 | }); |
| 50 | |
| 51 | test("an answer, even an error, is passed on as it is", async () => { |
| 52 | const response = await forward(new Request("https://example.com/"), async () => new Response("no", { status: 503 }), sleep); |
| 53 | assert.equal(response.status, 503); |
| 54 | }); |