securitygame.js

var express = require('express'),
    app     = express(),
    _       = require('lodash'),
    conf    = require('config');

app.use('/docs', express.static('docs'));

module.exports.generateResponse = generateResponse;
module.exports.getNextLevel = getNextLevel;
module.exports.namedIndex = {}; // for reverse-lookups.

// API's Home Document
app.get('/', function(req, res) {
    res.redirect('/docs/help.html');
});

app.get('/starthere', function(req, res){
    var firstLevel = 1;
    var response = {message: "The first API is located at " +  conf.levels[0].uri + ".  Good Luck!"};
    res.send(response);
})

// Set up levels
conf.levels.forEach(setupChallengeLevel);

function setupChallengeLevel(currLevel, levelIndex, allLevels) {
  // Level's task
  
  // Humans love indexes that start with 1, but machins love 0s
  currLevel.index = levelIndex;
  module.exports.namedIndex[currLevel.name] = currLevel;
    
  var props = {};
  props.objective    = currLevel.objective;
  props.instructions = currLevel.instructions;
  
  var links = {};
  
  // Do we have a documentation link?
  if (currLevel.docs) {
    links.documentation = currLevel.docs;
  }
       
  // Do we have any hints to take care of?      
  if (currLevel.hints && Array.isArray(currLevel.hints)) {
    links.hint = currLevel.hints[0].uri;        
      
    var hint0props = {};
        hint0props.message = currLevel.hints[0].message;
    var hint0links = {};
        
    // Do we have second hint? (rare).
    if (currLevel.hints[1]) {
      hint0links.hint = currLevel.hints[1].uri
      app.get(currLevel.hints[1].uri, function(req, res) {          
        
        var hint1properties = { message: currLevel.hints[1].message }
        var hint1response = generateResponse(levelIndex, 
                                             hint1properties);
        res.send(hint1response);
      });
      
    }
        
    app.get(currLevel.hints[0].uri, function(req, res) {        
      var hint0response = generateResponse(levelIndex, hint0props, hint0links);    
      res.send(hint0response);
    });  
  }
  
  // Response route for the level's task
  app.get(currLevel.uri, function(req, res) {    
      var response = generateResponse( levelIndex, 
                                       props, links);

      if (currLevel.headers && currLevel.headers.length > 0) { 
        for ( var headerIdx in currLevel.headers ) {
          // Header entries in our config are single string, because
          // YAML can be a major pain in the neck with characters in the keys
          // so we have to split those here, post-factum:
          var headerParts = currLevel.headers[headerIdx].split(":");
          res.set(_(headerParts[0]).trim(), _(headerParts[1]).trim());
        }
      }
                                       
      res.send(response);
  });
    
  // Level's solution
  if (currLevel.solution && currLevel.solution.module) {
    var attachURI = currLevel.uri;
    if (currLevel.solution.uri) attachURI = currLevel.solution.uri;
    app.use(attachURI, require("./lib/" + currLevel.name));
  }

  if (currLevel.solution && currLevel.solution.uri && !currLevel.solution.module) {
    app.get(currLevel.solution.uri, function( req, res ) {
        
        if (allLevels && allLevels[levelIndex+1] && allLevels[levelIndex+1].uri) {
          var nextLevelUri = allLevels[levelIndex+1].uri;
        }        

        lessons = currLevel.solution.lessons || [];
        
        var response = 
          generateResponse( levelIndex, 
                            { message: currLevel.solution.response },
                            { next: nextLevelUri },
                            lessons);                            
        res.send(response);
    });    
  }
    
}


var port = process.env.PORT || 8082;
app.listen(port);
console.log('Express server started on port %s', port);

//--- Helper Functions

function generateResponse(levelIndex, properties, links, lessons) {
    var response = {};
    
    // Humans love indexes that start with 1, but machins love 0s
    if (levelIndex) {
      response.level = levelIndex + 1; 
    }
    
    for( var key in properties ) {
        response[key] = properties[key];
    }
    
    if ( links ) {
        response.links = [];
        for( var key in links ) {
            response.links.push({rel: key, href: links[key]});
        }
    }
    if (response.links && response.links.length < 1 ) { delete response.links; }

    if ( lessons && Array.isArray(lessons) && lessons.length > 0) {
      response["lessons-learned"] = lessons;
      //for( var key in lessons ) {
      //    response.lessons.push({rel: key, href: lessons[key]});
      //}
    }
    if (response.lessons && response.lessons.length < 1 ) { delete response.lessons; }
  
    return response;
}

function getNextLevel(currentLevelName) {
    // Find this level identifier in the array of levels
    var index = -1;
    for ( var i = 0; i < conf.levels.length; i++ ) {
        if ( conf.levels[i].name === currentLevelName ) {
            index = i;
            break;
        }
    }

    if ( index < 0 || index === conf.levels.length ) {
        return {};
    } else {
        return conf.levels[index+1];        
    }    
}