Skip to content

test(api): use random ports for getFreePort e2e tests #179

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
chenjiahan merged 2 commits into from
Apr 1, 2026
Merged

test(api): use random ports for getFreePort e2e tests #179

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
b48cef0
test(api): use random ports for getFreePort e2e tests
chenjiahan Apr 1, 2026
4de6d50
test(api): make getFreePort CI checks deterministic
chenjiahan Apr 1, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
82 changes: 65 additions & 17 deletions tests/e2e/api.test.js
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -1,9 +1,14 @@
const path = require('node:path');
const net = require('node:net');
const { rspack } = require('@rspack/core');
const { RspackDevServer: Server } = require('@rspack/dev-server');
const config = require('../fixtures/client-config/rspack.config');
const runBrowser = require('../helpers/run-browser');
const sessionSubscribe = require('../helpers/session-subscribe');
const {
getRandomPorts,
releaseRandomPorts,
} = require('../helpers/get-random-port');
const port = require('../helpers/ports-map').api;

describe('API', () => {
Expand Down Expand Up @@ -337,12 +342,19 @@ describe('API', () => {
});

describe('Server.getFreePort', () => {
let basePort;
let reservedPorts = [];
let dummyServers = [];
let devServerPort;

beforeEach(async () => {
reservedPorts = await getRandomPorts(8, '0.0.0.0');
[basePort] = reservedPorts;
});

afterEach(() => {
process.env.RSPACK_DEV_SERVER_BASE_PORT = undefined;
process.env.RSPACK_DEV_SERVER_PORT_RETRY = undefined;
delete process.env.RSPACK_DEV_SERVER_BASE_PORT;
delete process.env.RSPACK_DEV_SERVER_PORT_RETRY;

return dummyServers
.reduce(
Expand All @@ -359,18 +371,20 @@ describe('API', () => {
)
.then(() => {
dummyServers = [];
releaseRandomPorts(reservedPorts);
reservedPorts = [];
});
});

function createDummyServers(n) {
process.env.RSPACK_DEV_SERVER_BASE_PORT = 60000;
process.env.RSPACK_DEV_SERVER_BASE_PORT = `${basePort}`;

return (Array.isArray(n) ? n : [...new Array(n)]).reduce(
(p, _, i) =>
p.then(
() =>
new Promise((resolve) => {
devServerPort = 60000 + i;
devServerPort = basePort + i;
const compiler = rspack(config);
const server = new Server(
{ port: devServerPort, host: '0.0.0.0' },
Expand Down Expand Up @@ -407,7 +421,7 @@ describe('API', () => {

const freePort = await Server.getFreePort(null);

expect(freePort).toEqual(60000 + retryCount);
expect(freePort).toEqual(basePort + retryCount);

const { page, browser } = await runBrowser();

Expand Down Expand Up @@ -447,7 +461,7 @@ describe('API', () => {
// eslint-disable-next-line no-undefined
const freePort = await Server.getFreePort(undefined);

expect(freePort).toEqual(60000 + retryCount);
expect(freePort).toEqual(basePort + retryCount);

const { page, browser } = await runBrowser();

Expand Down Expand Up @@ -486,7 +500,7 @@ describe('API', () => {

const freePort = await Server.getFreePort();

expect(freePort).toEqual(60000 + retryCount);
expect(freePort).toEqual(basePort + retryCount);

const { page, browser } = await runBrowser();

Expand Down Expand Up @@ -525,7 +539,7 @@ describe('API', () => {

const freePort = await Server.getFreePort();

expect(freePort).toEqual(60000 + retryCount);
expect(freePort).toEqual(basePort + retryCount);

const { page, browser } = await runBrowser();

Expand Down Expand Up @@ -556,15 +570,15 @@ describe('API', () => {
});

it('should retry finding the port when serial ports are busy', async () => {
const busyPorts = [60000, 60001, 60002, 60003, 60004, 60005];
const busyPorts = reservedPorts.slice(0, 6);

process.env.RSPACK_DEV_SERVER_PORT_RETRY = 1000;

await createDummyServers(busyPorts);

const freePort = await Server.getFreePort();

expect(freePort).toBeGreaterThan(60005);
expect(freePort).toBeGreaterThan(busyPorts[busyPorts.length - 1]);

const { page, browser } = await runBrowser();

Expand Down Expand Up @@ -597,16 +611,50 @@ describe('API', () => {
});

it("should throw the error when the port isn't found", async () => {
rs.doMockRequire(
'../../dist/getPort',
() => () => Promise.reject(new Error('busy')),
);
const busyServers = [];
const busyPorts = [65534, 65535];

process.env.RSPACK_DEV_SERVER_PORT_RETRY = 1;
try {
await Promise.all(
busyPorts.map(
(busyPort) =>
new Promise((resolve, reject) => {
const server = net.createServer();

server.unref();
server.on('error', reject);
server.listen(busyPort, '0.0.0.0', () => {
busyServers.push(server);
resolve();
});
}),
),
);

const { RspackDevServer: Server } = require('@rspack/dev-server');
process.env.RSPACK_DEV_SERVER_BASE_PORT = '65534';
process.env.RSPACK_DEV_SERVER_PORT_RETRY = 0;

await expect(Server.getFreePort()).rejects.toThrowErrorMatchingSnapshot();
await expect(
Server.getFreePort(),
).rejects.toThrowErrorMatchingSnapshot();
} finally {
await Promise.all(
busyServers.map(
(server) =>
new Promise((resolve, reject) => {
server.close((error) => {
if (error) {
reject(error);

return;
}

resolve();
});
}),
),
);
}
});
});

Expand Down
105 changes: 105 additions & 0 deletions tests/helpers/get-random-port.js
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,105 @@
const net = require('node:net');

const minRandomPort = 15000;
const maxRandomPort = 45000;

async function isPortAvailable(port, host = '0.0.0.0') {
try {
const server = net.createServer();

server.unref();

return await new Promise((resolve) => {
server.on('listening', () => {
server.close(() => {
resolve(true);
});
});
server.on('error', () => {
resolve(false);
});
server.listen(port, host);
});
} catch {
return false;
}
}

const portMap = new Map();

function getDefaultPort() {
return Math.ceil(Math.random() * 30000) + minRandomPort;
}

async function findAvailablePort(startPort, count, host) {
let port = Math.max(startPort, minRandomPort);
const maxStartPort = maxRandomPort - count + 1;

while (port <= maxStartPort) {
let isAvailable = true;

for (let index = 0; index < count; index += 1) {
const currentPort = port + index;

if (
portMap.get(currentPort) ||
!(await isPortAvailable(currentPort, host))
) {
isAvailable = false;
break;
}
}

if (isAvailable) {
return port;
}

port += 1;
}

throw new Error('No available ports found');
}

/**
* Get a random port.
* Available port ranges: 1024 ~ 65535
* `10080` is not available on macOS CI, `> 50000` gets "permission denied" on Windows,
* so we use `15000` ~ `45000`.
*/
async function getRandomPort(defaultPort = getDefaultPort(), host) {
const port = await findAvailablePort(defaultPort, 1, host);

portMap.set(port, 1);

return port;
}

async function getRandomPorts(count, host) {
if (count < 1) {
throw new Error('Port count must be greater than 0');
}

const port = await findAvailablePort(getDefaultPort(), count, host);
const ports = [];

for (let index = 0; index < count; index += 1) {
const currentPort = port + index;

portMap.set(currentPort, 1);
ports.push(currentPort);
}

return ports;
}

function releaseRandomPorts(ports = []) {
for (const port of ports) {
portMap.delete(port);
}
}

module.exports = {
getRandomPort,
getRandomPorts,
releaseRandomPorts,
};