Better file structure and naming

lib/db.coffee

@@ -0,0 +1,155 @@
+config = require './config'
+mongodb = require 'mongodb'
+redisClient = require('redis').createClient(config.REDIS_SOCKET)
+parameters = require './parameters'
+
+tasksCollection = null
+devicesCollection = null
+presetsCollection = null
+objectsCollection = null
+
+mongodb.MongoClient.connect("mongodb://#{config.MONGODB_SOCKET}/#{config.DATABASE_NAME}", config.MONGODB_OPTIONS, (err, db) ->
+  exports.mongoDb = db
+  db.collection('tasks', (err, collection) ->
+    throw new Error(err) if err?
+    exports.tasksCollection = tasksCollection = collection
+    collection.ensureIndex({device: 1, timestamp: 1}, (err) ->
+    )
+  )
+
+  db.collection('devices', (err, collection) ->
+    throw new Error(err) if err?
+    exports.devicesCollection  = devicesCollection = collection
+  )
+
+  db.collection('presets', (err, collection) ->
+    throw new Error(err) if err?
+    exports.presetsCollection = presetsCollection = collection
+  )
+
+  db.collection('objects', (err, collection) ->
+    throw new Error(err) if err?
+    exports.objectsCollection = objectsCollection = collection
+  )
+
+  db.collection('fs.files', (err, collection) ->
+    throw new Error(err) if err?
+    exports.filesCollection = filesCollection = collection
+  )
+)
+
+
+getTask = (taskId, callback) ->
+  tid = String(taskId)
+  redisClient.get(tid, (err, res) ->
+    return callback(err) if err
+    if res?
+      callback(err, JSON.parse(res))
+    else
+      tasksCollection.findOne({_id : mongodb.ObjectID(tid)}, (err, task) ->
+        callback(err, task)
+      )
+  )
+
+
+getCached = (name, valueCallback, valueExpiry, callback) ->
+  redisClient.get(name, (err, res) ->
+    return callback(err) if err
+    return callback(null, JSON.parse(res)) if res?
+
+    lockAcquired = () ->
+      valueCallback((err, value) ->
+        return callback(err, value) if err
+        redisClient.setex(name, valueExpiry, JSON.stringify(value), (err) ->
+          return callback(err, value) if err
+          redisClient.del("lock.#{name}", (err) ->
+            callback(err, value)
+          )
+        )
+      )
+
+    redisClient.setnx("lock.#{name}", Date.now() + 30000, (err, res) ->
+      return callback(err) if err
+      if res == 1
+        lockAcquired()
+      else
+        setTimeout(() ->
+          redisClient.get("lock.#{name}", (err, timestamp) ->
+            return callback(err) if err
+            now = Date.now()
+            if not timestamp?
+              getCached(name, valueCallback, valueExpiry, callback)
+            else if timestamp > now
+              setTimeout(() ->
+                getCached(name, valueCallback, valueExpiry, callback)
+              , 1000)
+            else
+              redisClient.getset("lock.#{name}", now + 30000, (err, timestamp) ->
+                return callback(err) if err
+                if timestamp > now
+                  setTimeout(() ->
+                    getCached(name, valueCallback, valueExpiry, callback)
+                  , 1000)
+                else
+                  lockAcquired()
+              )
+          )
+        , 1000)
+    )
+  )
+
+
+getAliases = (callback) ->
+  getCached('aliases', parameters.compileAliases, config.PRESETS_CACHE_DURATION, (err, res) ->
+    throw err if err
+    callback(res)
+  )
+
+
+getPresetsObjectsAliases = (callback) ->
+  redisClient.mget('presets', 'objects', 'aliases', (err, res) ->
+    presets = JSON.parse(res[0])
+    objects = JSON.parse(res[1])
+    aliases = JSON.parse(res[2])
+
+    if presets and objects and aliases
+      return callback(presets, objects, aliases)
+
+    if not presets
+      getCached('presets', (callback) ->
+        presetsCollection.find().toArray((err, res) ->
+          callback(err, res)
+        )
+      , config.PRESETS_CACHE_DURATION, (err, res) ->
+        throw err if err
+        presets = res
+        callback(presets, objects, aliases) if objects and aliases
+      )
+
+    if not objects
+      getCached('objects', (callback) ->
+        objectsCollection.find().toArray((err, res) ->
+          return callback(err) if err
+          objs = {}
+          objs[r._id] = r for r in res
+          callback(null, objs)
+        )
+      , config.PRESETS_CACHE_DURATION, (err, res) ->
+        throw err if err
+        objects = res
+        callback(presets, objects, aliases) if presets and aliases
+      )
+
+    if not aliases
+      getCached('aliases', parameters.compileAliases, config.PRESETS_CACHE_DURATION, (err, res) ->
+        throw err if err
+        aliases = res
+        callback(presets, objects, aliases) if presets and objects
+      )
+  )
+
+
+exports.redisClient = redisClient
+exports.getTask = getTask
+exports.getPresetsObjectsAliases = getPresetsObjectsAliases
+exports.getAliases = getAliases