feat(User): add Datastore support

Author: mistydemeo

docs/scripting.md

@@ -623,6 +623,21 @@ robot.respond /sleep it off/i, (res) ->
     res.reply 'zzzzz'
 ```
 
+The datastore also allows setting and getting values which are scoped to individual users:
+
+```coffeescript
+module.exports = (robot) ->
+
+  robot.respond /who is @?([\w .\-]+)\?*$/i, (res) ->
+    name = res.match[1].trim()
+
+    users = robot.brain.usersForFuzzyName(name)
+    if users.length is 1
+      user = users[0]
+      user.get('roles').then (roles) ->
+        res.send "#{name} is #{roles.join(', ')}"
+```
+
 ## Script Loading
 
 There are three main sources to load scripts from:

src/brain.js

@@ -10,7 +10,7 @@ const User = require('./user')
 // 2. If the original object was a User object, the original object
 // 3. If the original object was a plain JavaScript object, return
 //    a User object with all of the original object's properties.
-let reconstructUserIfNecessary = function (user) {
+let reconstructUserIfNecessary = function (user, robot) {
   if (!user) {
     return null
   }
@@ -20,6 +20,9 @@ let reconstructUserIfNecessary = function (user) {
     delete user.id
     // Use the old user as the "options" object,
     // populating the new user with its values.
+    // Also add the `robot` field so it gets a reference.
+    user.robot = robot
+
     return new User(id, user)
   } else {
     return user
@@ -36,6 +39,7 @@ class Brain extends EventEmitter {
       users: {},
       _private: {}
     }
+    this.robot = robot
 
     this.autoSave = true
 
@@ -142,7 +146,7 @@ class Brain extends EventEmitter {
     if (data && data.users) {
       for (let k in data.users) {
         let user = this.data.users[k]
-        this.data.users[k] = reconstructUserIfNecessary(user)
+        this.data.users[k] = reconstructUserIfNecessary(user, this.robot)
       }
     }
 
@@ -161,6 +165,10 @@ class Brain extends EventEmitter {
   // Returns a User instance of the specified user.
   userForId (id, options) {
     let user = this.data.users[id]
+    if (!options) {
+      options = {}
+    }
+    options.robot = this.robot
 
     if (!user) {
       user = new User(id, options)

src/user.js

@@ -1,5 +1,7 @@
 'use strict'
 
+const DataStoreUnavailable = require('./datastore').DataStoreUnavailable
+
 class User {
   // Represents a participating user in the chat.
   //
@@ -12,6 +14,17 @@ class User {
       options = {}
     }
 
+    // Define a getter method so we don't actually store the
+    // robot itself on the user object, preventing it from
+    // being serialized into the brain.
+    if (options.robot) {
+      let robot = options.robot
+      delete options.robot
+      this._getRobot = function () { return robot }
+    } else {
+      this._getRobot = function () { }
+    }
+
     Object.keys(options).forEach((key) => {
       this[key] = options[key]
     })
@@ -20,6 +33,33 @@ class User {
       this.name = this.id.toString()
     }
   }
+
+  set (key, value) {
+    this._checkDatastoreAvailable()
+    return this._getDatastore()._set(this._constructKey(key), value, 'users')
+  }
+
+  get (key) {
+    this._checkDatastoreAvailable()
+    return this._getDatastore()._get(this._constructKey(key), 'users')
+  }
+
+  _constructKey (key) {
+    return `${this.id}+${key}`
+  }
+
+  _checkDatastoreAvailable () {
+    if (!this._getDatastore()) {
+      throw new DataStoreUnavailable('datastore is not initialized')
+    }
+  }
+
+  _getDatastore () {
+    let robot = this._getRobot()
+    if (robot) {
+      return robot.datastore
+    }
+  }
 }
 
 module.exports = User

test/datastore_test.js

@@ -113,4 +113,38 @@ describe('Datastore', function () {
       })
     })
   })
+
+  describe('User scope', function () {
+    it('has access to the robot object', function () {
+      let user = this.robot.brain.userForId('1')
+      expect(user._getRobot()).to.equal(this.robot)
+    })
+
+    it('can store user data which is separate from global data', function () {
+      let user = this.robot.brain.userForId('1')
+      return user.set('blah', 'blah').then(() => {
+        return user.get('blah').then((userBlah) => {
+          return this.robot.datastore.get('blah').then((datastoreBlah) => {
+            expect(userBlah).to.not.equal(datastoreBlah)
+            expect(userBlah).to.equal('blah')
+            expect(datastoreBlah).to.be.an('undefined')
+          })
+        })
+      })
+    })
+
+    it('stores user data separate per-user', function () {
+      let userOne = this.robot.brain.userForId('1')
+      let userTwo = this.robot.brain.userForId('2')
+      return userOne.set('blah', 'blah').then(() => {
+        return userOne.get('blah').then((valueOne) => {
+          return userTwo.get('blah').then((valueTwo) => {
+            expect(valueOne).to.not.equal(valueTwo)
+            expect(valueOne).to.equal('blah')
+            expect(valueTwo).to.be.an('undefined')
+          })
+        })
+      })
+    })
+  })
 })