// ─── ✏️ YOUR TURN ─────────────────────────── // Lesson 17: a test harness for the API. // ── given: matchers ── const show = (value) => { const text = JSON.stringify(value); return text === undefined ? "undefined" : text.length > 70 ? text.slice(0, 67) + "..." : text; }; class Matcher { constructor(description, test) { this.description = description; this.test = test; } } const is = { string: () => new Matcher("a string", (v) => typeof v === "string"), number: () => new Matcher("a number", (v) => typeof v === "number"), oneOf: (...values) => new Matcher(`one of ${values.map(show).join(", ")}`, (v) => values.includes(v)), matching: (regex) => new Matcher(`text matching ${regex}`, (v) => typeof v === "string" && regex.test(v)), absent: () => new Matcher("absent", (v) => v === undefined), arrayOf: (count) => new Matcher(`an array of ${count} items`, (v) => Array.isArray(v) && v.length === count), }; // Compare 'actual' with the pattern 'expected' and return a list of problems (empty = match). // Matcher -> expected.test(actual); problem ": expected , got " // array -> actual must be an array of the same length; compare element by element, paths like "items[2]" // plain object -> actual must be an object; every key of expected must match (EXTRA keys in actual are fine), paths like "body.page.total" // anything else -> strict equality; problem ": expected , got " // an empty path is shown as "value"; type problems read ": expected an array, got ..." / "expected an object, got ..." function matches(actual, expected, path = "") { // TODO } // A case: { name, as?: riderId, request: { method, url, headers?, body? }, expect: { status, headers?, body? } } const SUITE_PINS = { "u-ana": "4821", "u-ben": "7390", "u-mia": "1156", "u-root": "9034" }; // Run every case in order and return { total, passed, results: [{ name, ok, failures: [string] }] }. // For case number i (from 0): // - call options.reset() first (default: () => db.reset()) // - the client address is "10.200.0." + (i + 1) for the login AND the request // - when the case has 'as', log in first: send POST /auth/token { riderId, pin: SUITE_PINS[riderId] } through options.send and add // the header authorization: "Bearer "; a failed login is the failure "login as failed with status " (skip the request) // - send the request with options.send (default: handle) as { method, url, headers, body, ip } // - compare: status (strict), expect.headers (matches against the response headers) and expect.body (matches against the response body), // prefixing header problems with "headers." and body problems with "body" (so "body.page.total") // - an exception while sending is the failure "request crashed: " async function runCases(cases, options = {}) { // TODO } // ── the suite ── // Three cases are given. Write at least eight more (see the list below) so the suite covers // the status codes 200, 201, 304, 400, 401, 403, 404, 409 and 412. const suite = [ { name: "lists all eight stations", request: { method: "GET", url: "/stations" }, expect: { status: 200, body: { items: is.arrayOf(8), page: { total: 8 } } } }, { name: "reads one station", request: { method: "GET", url: "/stations/st-03" }, expect: { status: 200, body: { id: "st-03", name: "Tram Depot", capacity: 14 } } }, { name: "an unknown station is a problem document", request: { method: "GET", url: "/stations/st-99" }, expect: { status: 404, headers: { "content-type": "application/problem+json" }, body: { type: is.matching(/\/not-found$/), status: 404, requestId: is.matching(/^req-/) } }, }, // TODO more cases, for example: // - an admin posting { name: "x", zone: "moon" } to /stations gets 400 and an errors array of 3 // - a rider (u-ana) creating a valid station gets 403 // - GET /rentals with no login gets 401 and a www-authenticate header starting with Bearer // - u-ana renting bk-109 WITHOUT an idempotency-key gets 400 (type ending idempotency-key-required) // - u-ana renting bk-109 WITH the header idempotency-key: "suite-rent-0001" gets 201 with riderId u-ana, returnedAt null and a location header /rentals/rt-... // - u-ben reading rental rt-1001 (Ana's) gets 404 // - GET /stations/st-01 with if-none-match: "*" gets 304 and a null body // - u-mia PATCHing st-01 { capacity: 13 } with if-match: "\"stale\"" gets 412 // - u-root deleting st-03 (bikes docked) gets 409 // - GET /health/ready gets 200 ]; // The control room calls this. async function runSuite() { // TODO: return runCases(suite) }