wait-for-port/test/all.js

wait for host/port to become available

var waitForPort = require('../index'),
    net = require('net'),
    sinon = require('sinon'),
    should = require('should'),
    helpers = require('./helpers'),
    assert = require('assert');

describe('waitForPort', function() {

  var clock;
  before(function() { clock = sinon.useFakeTimers(); });
  after(function() { clock.restore(); });

  function tryToConnect(host, port, cb) {
    var client = net.createConnection(port, host, function() {
      client.end();
      cb(null);
    });
  }

  describe('when port is not open', function() {

    var host = 'localhost', port;
    var server = null;

    before(function(done) {
      helpers.nextRandomPort(function(err, next) {
        port = next;
        done(err);
      });
    });

    beforeEach(function() {
      server = net.createServer();
    });
    afterEach(function(done) {
      server.close(done);
    });

    it('calls us back', function(done) {

      var portIsReady = false;
      waitForPort(host, port, function(err) {
        if (err) return done(err);
        portIsReady.should.be.true;
        done(); // called more than once?
      });
      server.listen(port, function() {
        portIsReady = true;
      });
      clock.tick(10); // TODO: magic number

    });

  });

  describe('when port is open already', function() {

    var host = 'localhost', port;
    var server;

    before(function(done) {
      server = net.createServer();
      server.listen(0 /* any port */, function() {
        var address = server.address();
        port = address.port;
        // console.log('listening on port ' + port);
        done();
      });
    });
    after(function(done) {
      server.close(function() {
        // console.log('server closed');
        done();
      });
    });
    it('calls us back', function(done) {
      waitForPort(host, port, function(err) {

        // no error
        (err === null).should.be.true;

        // can we connect?
        tryToConnect(host, port, done);

      });
    });
  });

  describe('retries', function() {
    var host = 'localhost', port;
    beforeEach(function(done) {
      helpers.nextRandomPort(function(err, next) {
        port = next;
        done(err);
      });
    });
    it('fails if no server and we run out of retries', function(done) {
      waitForPort(host, port, function(err) {
        err.should.match(/out of retries/);
        done();
      });
      clock.tick(50000000); // TODO: magic number
    })
  });

  describe('retries', function() {

    var host = 'localhost', port = 0;

    beforeEach(function(done) {
      helpers.nextRandomPort(function(err, next) {
        if (err) throw new Error(err);
        port = next;
        done();
      });
    });

    describe('invalid options', function() {

      it('fails for invalid options', function() {

        (function() {
          waitForPort(host, port, { numRetries: -1 }, function() {});
        }).should.throw(/invalid value for option/);

        (function() {
          waitForPort(host, port, { retryInterval: -1 }, function() {});
        }).should.throw(/invalid value for option/);

      });

    });

    var variations = [
      { numRetries: 1, retryInterval: 1 },
      { numRetries: 1, retryInterval: 10000 },
      { numRetries: 7, retryInterval: 1 },
      { numRetries: 7, retryInterval: 6577 }
    ];

    variations.forEach(function(options) {

      it('does callback with error when run out of retries, retries=' + options.numRetries + ', interval=' + options.retryInterval, function(done) {
        waitForPort(host, port, options, function(err) {
          err.should.match(/out of retries/);
          done();
        });
        clock.tick(options.numRetries * options.retryInterval + 1);
      });

      it('does not call back if numRetries and/or retryInterval large enough, retries=' + options.numRetries + ', interval=' + options.retryInterval, function(done) {
        var err = null;
        waitForPort(host, port, options, function() {
          err = new Error('should not be called');
        });
        clock.tick(options.numRetries * options.retryInterval - 1);
        done(err);
      });
    });

  });

});