grunt-vnuserver-dev/tasks/vnuserver.js

A Grunt plugin for starting the vnu.jar markup checker in server mode.

let javadetect = require('grunt-html-dev/lib/javadetect');
let jar = require('vnu-jar');
let path = require('path');
let portastic = require('portastic');

let MAX_PORTS = 30;

module.exports = function (grunt) {
    grunt.registerTask('vnuserver', 'Start the Nu Html Checker server.', function () {
        let opt = this.options({port: 8888, skippable: false, persist: false, useAvailablePort: false});
        let done = this.async();

        start(opt.port);

        function start (port) {
            portastic.test(port, function (open) {
                if (!open) {
                    if (opt.useAvailablePort) {
                        if (port < opt.port + MAX_PORTS) {
                            grunt.log.debug('Port ' + port + ' in use. Trying another one.');
                            process.nextTick(function () {
                                start(port + 1);
                            });
                        } else {
                            done(Error('Port ' + opt.port + ' and ' + MAX_PORTS + ' others in use. To ignore, set skippable: false.'));
                        }
                    } else if (opt.skippable) {
                        grunt.log.debug('Port ' + port + ' in use. Skipping server startup.');
                        done();
                    } else {
                        done(Error('Port ' + port + ' in use. To ignore, set skippable: false.'));
                    }
                    return;
                }

                grunt.config.set('vnuserver.options.port', port);
                grunt.event.emit('vnuserver.listening', port);

                let child;
                let cleanup = function () {
                    let killing = grunt.log.write('Killing vnuserver...');
                    child.kill('SIGKILL');
                    killing.ok();
                };
                if (!opt.persist) {
                    process.on('exit', cleanup);
                    let exit = grunt.util.exit;
                    grunt.util.exit = function () { // This seems to be the only reliable on-exit hook.
                        cleanup();
                        return exit.apply(grunt.util, arguments);
                    };
                }

                javadetect(function(err, java) {
                    if (err) {
                        throw err;
                    }
                    let args = [
                      (java.arch === 'ia32' ? '-Xss512k' : ''),
                      '-Dnu.validator.servlet.log4j-properties=' +
                        path.join(__dirname, 'log4j.properties'),
                      '-Dnu.validator.servlet.read-local-log4j-properties=1',
                      '-cp', jar, 'nu.validator.servlet.Main', port
                    ].filter(x => x);
                    let vnustartup = grunt.log.write('Starting vnuserver on port ' + port + '...');
                    child = grunt.util.spawn({cmd: 'java', args: args}, function(error /*, stdout, stderr*/) {
                        if (error && (error.code !== 1 || error.killed || error.signal)) {
                            done(false);
                        }
                    });
                    child.stderr.on('data', function (chunk) {
                        if (chunk.toString().indexOf('org.eclipse.jetty.server.Server: Started') >= 0) {
                            vnustartup.ok();
                            done();
                        }
                        if (chunk.toString().indexOf('java.net.BindException: Address already in use') >= 0) {
                            vnustartup.error();
                            done(Error('Port ' + port + ' in use. Shutting down.'));
                            cleanup();
                        }
                    });
                });
            });
        }
    });
};