server.js

#!/usr/bin/env node

'use strict';

var http = require('http');
var url = require('url');
var fs = require('fs');
var mime = require('mime');
var exec = require('child_process').exec;
var port = 20080;
var db = {};

var doGet = function(req, res) {
  var pathName = url.parse(req.url)['pathname'];
  if (pathName === '/last') {
    doGetLastFile(res);
  } else {
    if (pathName === '/') {
      pathName += 'index.html';
    }
    pathName = '.' + pathName;
    fs.exists(pathName, function(exists) {
      if (exists) {
        doGetFile(pathName, res);
      } else {
        doGetData(req.headers['user-agent'], res);
      }
    });
  }
};

var doGetFile = function(path, res) {
  fs.readFile(path, function(e, content) {
    if (e) {
      res.writeHead(404, e.message,
      { 'Content-Length': 0, 'Connection': 'close'});
    } else {
      res.writeHead(200, {
        'Content-Length': content.length,
        'Content-Type': mime.lookup(path),
      'Connection': 'close'});
      res.write(content);
    }
    res.end();
  });
};

var doGetData = function(key, res) {
  var data = db[key];
  if (data) {
    var json = JSON.stringify(data);
    res.writeHead(200, {
      'Content-Length': Buffer.byteLength(json),
      'Content-Type': 'application/json; charset=utf-8',
      'Connection': 'close'});
    console.log(json);
    res.write(json);
  } else {
    res.writeHead(404, { 'Content-Length': 0, 'Connection': 'close'});
  }
  res.end();
};

var doGetLastFile = function(res) {
  var data = db['last_file'];
  if (data) {
    res.writeHead(200, {
      'Content-Length': data.length,
      'Content-Type': mime.lookup(data),
      'Connection': 'close'});
    res.write(data);
  } else {
    res.writeHead(404, { 'Content-Length': 0, 'Connection': 'close'});
  }
  res.end();
};

var doPost = function(req, res) {
  var data = '';
  req.on('data', function(chunk) {
    data += chunk;
  });
  req.on('end', function() {
    var api = url.parse(req.url)['pathname'];
    console.log(api);
    switch (api) {
      case '/data':
        try {
          var json = JSON.parse(data);
          console.log(json);
          db[req.headers['user-agent']] = json;
        } catch (e) {
          res.writeHead(400, e.message,
          { 'Content-Length': 0, 'Connection': 'close'});
        } finally {
          res.end();
        }
        break;
      case '/file':
        console.log(data);
        db['last_file'] = data;
        res.end();
        break;
      default:
        res.end();
        break;
    }
  });
};

var server = http.createServer(function(req, res) {
  if (req.method === 'GET') {
    console.log('GET');
    doGet(req, res);
  } else if (req.method === 'POST') {
    console.log('POST');
    doPost(req, res);
  }
});
server.on('clientError', function(e) {
  console.log('Client Error: ', e.message);
});

server.on('error', function(e) {
  console.log('Server Error: ', e.message);
});

exec('ifconfig |grep -1 "^eth0" |grep inet', function(err, stdout, stderr) {
  var result = stdout.match(/(\d{1,3}\.){3}\d{1,3}/);
  server.listen(port, function() {
    console.log('ip = ' + result[0]);
    console.log('port = ' + port);
    console.log('listening ...');
  });
});