sender.test.js

'use strict';

const assert = require('assert');

const PerMessageDeflate = require('../lib/permessage-deflate');
const Sender = require('../lib/sender');

class MockSocket {
  constructor ({ write, on, once, prependOnceListener } = {}) {
    if (write) this.write = write;
    if (on) this.on = on;
    if (once) this.once = once;
    if (prependOnceListener) this.prependOnceListener = prependOnceListener;
  }

  write () {}
  on () {}
  once () {}
  prependOnceListener () {}
}

describe('Sender', function () {
  describe('.frame', function () {
    it('does not mutate the input buffer if data is `readOnly`', function () {
      const buf = Buffer.from([1, 2, 3, 4, 5]);

      Sender.frame(buf, {
        readOnly: true,
        rsv1: false,
        mask: true,
        opcode: 2,
        fin: true
      });

      assert.ok(buf.equals(Buffer.from([1, 2, 3, 4, 5])));
    });

    it('sets RSV1 bit if compressed', function () {
      const list = Sender.frame(Buffer.from('hi'), {
        readOnly: false,
        mask: false,
        rsv1: true,
        opcode: 1,
        fin: true
      });

      assert.strictEqual(list[0][0] & 0x40, 0x40);
    });
  });

  describe('#send', function () {
    it('compresses data if compress option is enabled', function (done) {
      const perMessageDeflate = new PerMessageDeflate({ threshold: 0 });
      let count = 0;
      const mockSocket = new MockSocket({
        write: (data) => {
          assert.strictEqual(data[0] & 0x40, 0x40);
          if (++count === 3) done();
        }
      });
      const sender = new Sender(mockSocket, { 'permessage-deflate': perMessageDeflate });

      perMessageDeflate.accept([{}]);

      const options = { compress: true, fin: true };
      const array = new Uint8Array([0x68, 0x69]);

      sender.send(array.buffer, options);
      sender.send(array, options);
      sender.send('hi', options);
    });

    it('does not attempt to compress enqueued messages after socket closes', function (done) {
      const perMessageDeflate = new PerMessageDeflate({ threshold: 0 });
      const numMessages = 1000;
      let numWritten = 0;
      const mockSocket = new MockSocket({
        write: (data) => {
          assert.strictEqual(data[0] & 0x40, 0x40);
          if (++numWritten > 1) done(new Error('Too many attempted writes'));
        },
        once: (ev, cb) => {
          if (ev === 'close') {
            process.nextTick(cb);
          }
        }
      });
      const sender = new Sender(mockSocket, { 'permessage-deflate': perMessageDeflate });

      let numCompressed = 0;

      perMessageDeflate.compress = (data, fin, cb) => {
        if (++numCompressed > 1) {
          done(new Error('Compressed too many times'));
        }

        setTimeout(() => cb(null, data), 1);
      };

      perMessageDeflate.accept([{}]);

      const options = { compress: true, fin: false };
      const array = new Uint8Array([0x68, 0x69]);

      sender.send(array.buffer, options, () => {});
      sender.send(array, options, () => {});

      let numErrors = 0;
      for (let i = 0; i < numMessages; ++i) {
        sender.send('hi', options, (err) => {
          if (!err) return;

          if (++numErrors === numMessages) {
            done();
          }
        });
      }
    });

    it('does not compress data for small payloads', function (done) {
      const perMessageDeflate = new PerMessageDeflate();
      const mockSocket = new MockSocket({
        write: (data) => {
          assert.notStrictEqual(data[0] & 0x40, 0x40);
          done();
        }
      });
      const sender = new Sender(mockSocket, { 'permessage-deflate': perMessageDeflate });

      perMessageDeflate.accept([{}]);

      sender.send('hi', { compress: true, fin: true });
    });

    it('compresses all frames in a fragmented message', function (done) {
      const fragments = [];
      const perMessageDeflate = new PerMessageDeflate({ threshold: 3 });
      const mockSocket = new MockSocket({
        write: (data) => {
          fragments.push(data);
          if (fragments.length !== 2) return;

          assert.strictEqual(fragments[0][0] & 0x40, 0x40);
          assert.strictEqual(fragments[0].length, 11);
          assert.strictEqual(fragments[1][0] & 0x40, 0x00);
          assert.strictEqual(fragments[1].length, 6);
          done();
        }
      });
      const sender = new Sender(mockSocket, { 'permessage-deflate': perMessageDeflate });

      perMessageDeflate.accept([{}]);

      sender.send('123', { compress: true, fin: false });
      sender.send('12', { compress: true, fin: true });
    });

    it('compresses no frames in a fragmented message', function (done) {
      const fragments = [];
      const perMessageDeflate = new PerMessageDeflate({ threshold: 3 });
      const mockSocket = new MockSocket({
        write: (data) => {
          fragments.push(data);
          if (fragments.length !== 2) return;

          assert.strictEqual(fragments[0][0] & 0x40, 0x00);
          assert.strictEqual(fragments[0].length, 4);
          assert.strictEqual(fragments[1][0] & 0x40, 0x00);
          assert.strictEqual(fragments[1].length, 5);
          done();
        }
      });
      const sender = new Sender(mockSocket, { 'permessage-deflate': perMessageDeflate });

      perMessageDeflate.accept([{}]);

      sender.send('12', { compress: true, fin: false });
      sender.send('123', { compress: true, fin: true });
    });

    it('compresses empty buffer as first fragment', function (done) {
      const fragments = [];
      const perMessageDeflate = new PerMessageDeflate({ threshold: 0 });
      const mockSocket = new MockSocket({
        write: (data) => {
          fragments.push(data);
          if (fragments.length !== 2) return;

          assert.strictEqual(fragments[0][0] & 0x40, 0x40);
          assert.strictEqual(fragments[0].length, 3);
          assert.strictEqual(fragments[1][0] & 0x40, 0x00);
          assert.strictEqual(fragments[1].length, 8);
          done();
        }
      });
      const sender = new Sender(mockSocket, { 'permessage-deflate': perMessageDeflate });

      perMessageDeflate.accept([{}]);

      sender.send(Buffer.alloc(0), { compress: true, fin: false });
      sender.send('data', { compress: true, fin: true });
    });

    it('compresses empty buffer as last fragment', function (done) {
      const fragments = [];
      const perMessageDeflate = new PerMessageDeflate({ threshold: 0 });
      const mockSocket = new MockSocket({
        write: (data) => {
          fragments.push(data);
          if (fragments.length !== 2) return;

          assert.strictEqual(fragments[0][0] & 0x40, 0x40);
          assert.strictEqual(fragments[0].length, 12);
          assert.strictEqual(fragments[1][0] & 0x40, 0x00);
          assert.strictEqual(fragments[1].length, 3);
          done();
        }
      });
      const sender = new Sender(mockSocket, { 'permessage-deflate': perMessageDeflate });

      perMessageDeflate.accept([{}]);

      sender.send('data', { compress: true, fin: false });
      sender.send(Buffer.alloc(0), { compress: true, fin: true });
    });

    it('handles many send calls while processing without crashing on flush', function (done) {
      let count = 0;
      const perMessageDeflate = new PerMessageDeflate();
      const mockSocket = new MockSocket({
        write: () => {
          if (++count > 1e4) done();
        }
      });
      const sender = new Sender(mockSocket, { 'permessage-deflate': perMessageDeflate });

      perMessageDeflate.accept([{}]);

      for (let i = 0; i < 1e4; i++) {
        sender.processing = true;
        sender.send('hi', { compress: false, fin: true });
      }

      sender.processing = false;
      sender.send('hi', { compress: false, fin: true });
    });
  });

  describe('#ping', function () {
    it('works with multiple types of data', function (done) {
      const perMessageDeflate = new PerMessageDeflate({ threshold: 0 });
      let count = 0;
      const mockSocket = new MockSocket({
        write: (data) => {
          if (++count === 1) return;

          assert.ok(data.equals(Buffer.from([0x89, 0x02, 0x68, 0x69])));
          if (count === 4) done();
        }
      });
      const sender = new Sender(mockSocket, { 'permessage-deflate': perMessageDeflate });

      perMessageDeflate.accept([{}]);

      const array = new Uint8Array([0x68, 0x69]);

      sender.send('foo', { compress: true, fin: true });
      sender.ping(array.buffer, false);
      sender.ping(array, false);
      sender.ping('hi', false);
    });
  });

  describe('#pong', function () {
    it('works with multiple types of data', function (done) {
      const perMessageDeflate = new PerMessageDeflate({ threshold: 0 });
      let count = 0;
      const mockSocket = new MockSocket({
        write: (data) => {
          if (++count === 1) return;

          assert.ok(data.equals(Buffer.from([0x8a, 0x02, 0x68, 0x69])));
          if (count === 4) done();
        }
      });
      const sender = new Sender(mockSocket, { 'permessage-deflate': perMessageDeflate });

      perMessageDeflate.accept([{}]);

      const array = new Uint8Array([0x68, 0x69]);

      sender.send('foo', { compress: true, fin: true });
      sender.pong(array.buffer, false);
      sender.pong(array, false);
      sender.pong('hi', false);
    });
  });

  describe('#close', function () {
    it('should consume all data before closing', function (done) {
      const perMessageDeflate = new PerMessageDeflate({ threshold: 0 });

      let count = 0;
      const mockSocket = new MockSocket({
        write: (data, cb) => {
          count++;
          if (cb) cb();
        }
      });
      const sender = new Sender(mockSocket, { 'permessage-deflate': perMessageDeflate });

      perMessageDeflate.accept([{}]);

      sender.send('foo', { compress: true, fin: true });
      sender.send('bar', { compress: true, fin: true });
      sender.send('baz', { compress: true, fin: true });

      sender.close(1000, undefined, false, () => {
        assert.strictEqual(count, 4);
        done();
      });
    });
  });
});