actionhero/initializers/stats.js

actionhero.js is a multi-transport API Server with integrated cluster capabilities and delayed tasks

module.exports = {
  startPriority: 900,
  stopPriority:  300,
  loadPriority:  310,
  initialize: function(api, next){
  
    api.stats = {};
    api.stats.timer = null;
    api.stats.pendingIncrements = {};

    api.stats.increment = function(key, count){
      if(!count){ count = 1; }
      count = parseFloat(count);
      if(!api.stats.pendingIncrements[key]){ api.stats.pendingIncrements[key] = 0 }
      api.stats.pendingIncrements[key] = api.stats.pendingIncrements[key] + count;
    }

    api.stats.writeIncrements = function(next){
      clearTimeout(api.stats.timer);
      // api.log('writing pending stats data', 'debug', api.stats.pendingIncrements);
      if(api.utils.hashLength(api.stats.pendingIncrements) > 0 && api.config.stats.keys.length > 0){
        var started = 0;
        var pendingIncrements = api.utils.objClone(api.stats.pendingIncrements);
        api.stats.pendingIncrements = {};
        for(var i in api.config.stats.keys){
          started++;
          var collection = api.config.stats.keys[i];
          (function(collection){
            var multi = api.redis.client.multi();
            for(var key in pendingIncrements){
              var value = pendingIncrements[key];
              multi.hincrby(collection, key, value);
            }
            multi.exec(function(){
              started--;
              if(started === 0){
                api.stats.timer = setTimeout(api.stats.writeIncrements, api.config.stats.writeFrequency);
                if(typeof next === 'function'){ next() }
              }
            });
          })(collection);
        }
      } else {
        api.stats.timer = setTimeout(api.stats.writeIncrements, api.config.stats.writeFrequency );
        if(typeof next === 'function'){ next() }
      }
    }

    api.stats.get = function(key, collection, next){
      if(!next && typeof collection === 'function'){ next = collection; collection = null; }
      if(!collection){ collection = api.config.stats.keys[0] }
      api.redis.client.hget(collection, key, function(err, value){
        next(err, value);
      });
    }

    api.stats.getAll = function(collections, next){
      if(!next && typeof collections === 'function'){ next = collections; collections = null; }
      if(!collections){ collections = api.config.stats.keys }

      var results = {};
      if(collections.length === 0){
        next(null, results);
      } else {
        for(var i in collections){
          var collection = collections[i];
          (function(collection){
            api.redis.client.hgetall(collection, function(err, data){
              if(!data){ data = {} }
              results[collection] = data;
              if(api.utils.hashLength(results) === collections.length){
                next(err, results);
              }
            });
          })(collection);
        }
      }
    }
    
    next();
  },

  start: function(api, next){
    if(api.config.stats.writeFrequency > 0){
      api.stats.timer = setTimeout(api.stats.writeIncrements, api.config.stats.writeFrequency);
    }
    next();
  },

  stop: function(api, next){
    clearTimeout(api.stats.timer);
    next();
  }
}