alexa-js · orlylev · Sep 18, 2018 · Sep 18, 2018 · Sep 23, 2018 · Oct 18, 2018
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -8,6 +8,7 @@
 * [#364](https://github.com/alexa-js/alexa-app/pull/364): Fix reprompt() to concatenate multiple SSML prompts - [@andrewjhunt](https://github.com/andrewjhunt).
 * [#371](https://github.com/alexa-js/alexa-app/pull/371): Call response.prepare() after post() - [@fremail](https://github.com/fremail).
 * [#373](https://github.com/alexa-js/alexa-app/pull/373): Keep multiple newlines in card output - [@kielni](https://github.com/kielni) and [@fremail](https://github.com/fremail).
+* [#378](https://github.com/alexa-js/alexa-app/pull/375): Implement CanFulfillIntent requests - [@orlylev](https://github.com/orlylev).
 * Your contribution here.
 
 ### 4.2.2 (April 7, 2018)

diff --git a/README.md b/README.md
@@ -22,6 +22,7 @@
     * [Display.ElementSelected](#display-element-selected)
     * [AudioPlayer Event Request](#audioplayer-event-request)
     * [PlaybackController Event Request](#playbackcontroller-event-request)
+    * [CanFulfillIntent Request](#canfulfillintent)
     * [Other Event Request](#other-event-request)
 * [Execute Code On Every Request](#execute-code-on-every-request)
     * [pre()](#pre)
@@ -468,7 +469,6 @@ app.displayElementSelected(function(request, response) {
   handleRequestForTouchEvent(request.selectedElementToken)
 })
 ```
-
 ### SessionEndRequest
 
 ```javascript
@@ -555,6 +555,35 @@ app.playbackController('NextCommandIssued', (request, response) => {
 
 Note that some device interactions don't always produce PlaybackController events. See the [PlaybackController Interface Introduction](https://developer.amazon.com/public/solutions/alexa/alexa-skills-kit/docs/custom-playbackcontroller-interface-reference#introduction) for more details.
 
+### CanFulfillIntent
+
+Define the handler for canFulfillIntent used for skill discovery.  For instance the [Implementation instructions](https://developer.amazon.com/docs/custom-skills/implement-canfulfillintentrequest-for-name-free-interaction.html).
+
+See detailed explanation on the Intent and Slot [logic](https://developer.amazon.com/docs/custom-skills/understand-name-free-interaction-for-custom-skills.html).
+
+
+```javascript
+app.canFulfillHandler(function(request, response) {
+  // The request object will return CanFulfillIntent object 
+  //by default the response will include "No" for the intent and slots
+  let canFulfillIntent =  request.getCanFulfillIntent();
+
+  //add your logic to determine if you can fulfill the intent and each slot
+  if(canFulfillIntent.name == 'HowTo' 
+    || canFulfillIntent.name == 'Information' || canFulfillIntent.name == 'Instructions')
+    { 
+      //we response YES for these intents that we can fulfill
+      response.canFulfill("YES");
+    }
+    else if(canFulfillIntent.name == 'GetPrice'){
+      //In this information we check if we can answer GetPrice intent with the slots values and decide to answer YES
+
+      //Do the logic ...      
+      response.canFulfillSlot("MyProduct","YES","YES");
+    } 
+});
+```
+
 ### Other Event Request
 
 Handle any new requests that don't have an explicit handler type available (such as new or pre-release features) using the general `on()` and passing the event type.

diff --git a/index.js b/index.js
@@ -186,6 +186,65 @@ alexa.response = function(session) {
     this.sessionObject.clear(key);
     return this;
   };
+
+  this.canFulfillIntent= function(slots){
+    this.canFulfillIntentValue = new alexa.canFulfillIntent(self.response.response, slots);
+    return this;
+  };
+
+  this.canFulfill = function(canFulfill){
+    if(!this.canFulfillIntentValue){
+      this.canFulfillIntentValue = new alexa.canFulfillIntent(self.response.response);
+    }
+    this.canFulfillIntentValue.canFulfill(canFulfill);
+    return this;
+  };
+
+  this.canFulfillSlot = function(slotName,canUnderstand, canFulfill){ 
+    if(!this.canFulfillIntentValue){
+      this.canFulfillIntentValue = new alexa.canFulfillIntent(self.response.response);
+    }
+    this.canFulfillIntentValue.canFulfillSlot(slotName,canUnderstand, canFulfill); 
+    return this; 
+  };
+};
+
+alexa.canFulfillIntent = function (response, slots) {
+  //load alexa slots information from CanFulfillIntentRequest
+  //create default response
+  this.canFulfillIntent = {
+    "canFulfill": "NO",
+    "slots": {}
+  };
+
+  response.canFulfillIntent = this.canFulfillIntent;
+  if (slots) {
+    for (let slotName in slots) {
+      let slotValue = {
+        "canUnderstand": "NO",
+        "canFulfill": "NO"
+      };
+      this.canFulfillIntent.slots[slotName] = slotValue;
+    }
+  }
+
+  this.canFulfill = function(canFulfill){    
+    this.canFulfillIntent.canFulfill = canFulfill;
+  };
+
+  this.canFulfillSlot = function(slotName,canUnderstand, canFulfill){  
+    if(this.canFulfillIntent.slots[slotName]){
+      let canFulfillSlot = this.canFulfillIntent.slots[slotName];
+      canFulfillSlot.canUnderstand = canUnderstand;
+      canFulfillSlot.canFulfill = canFulfill;
+    }
+    else{      
+      this.canFulfillIntent.slots[slotName] = {
+        "canUnderstand": canUnderstand,
+        "canFulfill": canFulfill
+      }; 
+    }    
+  };
 };
 
 alexa.directives = function(directives) {
@@ -196,11 +255,15 @@ alexa.directives = function(directives) {
     this.details.push(directive);
   };
 
+
+
   this.clear = function() {
     this.details.length = 0;
   };
 };
 
+
+
 alexa.request = function(json) {
   this.data = json;
   this.slots = {};
@@ -251,7 +314,9 @@ alexa.request = function(json) {
   this.context = null;
 
   if (this.data.context) {
-    this.userId = this.data.context.System.user.userId;
+    if(this.data.context.System && this.data.context.System.user){
+      this.userId = this.data.context.System.user.userId;
+    }
     this.applicationId = this.data.context.System.application.applicationId;
     this.context = this.data.context;
   }
@@ -283,6 +348,12 @@ alexa.request = function(json) {
   this.session = function(key) {
     return this.getSession().get(key);
   };
+
+  this.getCanFulfillIntent = function () {
+    if (this.data && this.data.request && this.data.request.intent) {      
+      return this.data.request.intent;
+    }   
+  };
 };
 
 alexa.dialog = function(dialogState) {
@@ -387,9 +458,13 @@ alexa.session = function(session) {
     // load the alexa session information into details
     this.details = session;
     // @deprecated
-    this.details.userId = this.details.user.userId || null;
-    // @deprecated
-    this.details.accessToken = this.details.user.accessToken || null;
+    this.details.userId = null;
+    this.details.accessToken = null;
+    if(this.details.user){
+      this.details.userId = this.details.user.userId || null;
+      this.details.accessToken = this.details.user.accessToken || null;
+    }
+
 
     // persist all the session attributes across requests
     // the Alexa API doesn't think session variables should persist for the entire
@@ -527,6 +602,10 @@ alexa.app = function(name) {
   this.sessionEnded = function(func) {
     self.sessionEndedFunc = func;
   };
+  this.canFulfillIntentFunc = null;
+  this.canFulfillIntent = function(func) {
+    self.canFulfillIntentFunc = func;
+  };
   this.request = function(request_json) {
     var request = new alexa.request(request_json);
     var response = new alexa.response(request.getSession());
@@ -543,7 +622,6 @@ alexa.app = function(name) {
         postPromise = Promise.resolve(self.post(request, response, requestType, exception));
       }
       return postPromise.then(function() {
-        response.prepare();
         if (!response.resolved) {
           response.resolved = true;
         }
@@ -558,7 +636,6 @@ alexa.app = function(name) {
         postPromise = Promise.resolve(self.post(request, response, requestType, exception));
       }
       return postPromise.then(function() {
-        response.prepare();
         if (!response.resolved) {
           response.resolved = true;
           throw msg;
@@ -618,7 +695,17 @@ alexa.app = function(name) {
             } else {
               throw "NO_DISPLAY_ELEMENT_SELECTED_FUNCTION";
             }
-          } else if (typeof self.requestHandlers[requestType] === "function") {
+          }  else if ("CanFulfillIntentRequest" === requestType) {
+            if (typeof self.canFulfillIntentFunc === "function") {
+              let reqIntent = request.getCanFulfillIntent();
+              if(reqIntent){
+                response.canFulfillIntent(reqIntent.slots);
+              }
+              return Promise.resolve(self.canFulfillIntentFunc(request, response));
+            } else {
+              throw "NO_CAN_FULFILL_FUNCTION";
+            }
+          }else if (typeof self.requestHandlers[requestType] === "function") {
             return Promise.resolve(self.requestHandlers[requestType](request, response, request_json));
           } else {
             throw "INVALID_REQUEST_TYPE";

diff --git a/package-lock.json b/package-lock.json
diff --git a/package.json b/package.json
@@ -47,7 +47,7 @@
     "babel-preset-es2015": "^6.24.1",
     "chai": "^3.4.1",
     "chai-as-promised": "^5.3.0",
-    "chai-string": "1.4.0",
+    "chai-string": "^1.3.0",
     "coveralls": "^2.11.9",
     "danger": "0.6.10",
     "ejs": "^2.5.5",

diff --git a/test/fixtures/can_fulfill_intent_request_no_intent.json b/test/fixtures/can_fulfill_intent_request_no_intent.json
@@ -0,0 +1,37 @@
+{
+    "version": "1.0",
+    "session": {
+      "new": false,
+      "sessionId": "amzn1.echo-api.session.abeee1a7-aee0-41e6-8192-e6faaed9f5ef",
+      "application": {
+        "applicationId": "amzn1.echo-sdk-ams.app.000000-d0ed-0000-ad00-000000d00ebe"
+      },
+      "attributes": {},
+      "user": {
+        "userId": "amzn1.account.AM3B227HF3FAM1B261HK7FFM3A2"
+      }
+    },
+	"context": {
+		"System": {
+			"application": {
+				"applicationId": "amzn1.echo-sdk-ams.app.000000-d0ed-0000-ad00-000000d00ebe"
+			},
+			"user": {
+				"userId": "amzn1.account.AM3B227HF3FAM1B261HK7FFM3A2",
+				"accessToken": "ae312e92d87d7b4e7648b19a08f2966a831a59de"
+			},
+			"device": {
+				"deviceId": "amzn1.ask.device.123456789",
+				"supportedInterfaces": {}
+			},
+			"apiEndpoint": "https://api.amazonalexa.com",
+			"apiAccessToken": "123456789"
+		}
+	},	
+  "request": {
+    "type": "CanFulfillIntentRequest",
+    "requestId": "amzn1.echo-api.request.e510e005-c518-44c8-930d-746c84e787da",    
+    "locale": "en-US",
+    "timestamp": "2018-10-18T09:16:28Z"
+  }
+}
diff --git a/test/fixtures/can_fulfill_intent_request_play_sound.json b/test/fixtures/can_fulfill_intent_request_play_sound.json
+{
+    "version": "1.0",
+    "session": {
+      "new": false,
+      "sessionId": "amzn1.echo-api.session.abeee1a7-aee0-41e6-8192-e6faaed9f5ef",
+      "application": {
+        "applicationId": "amzn1.echo-sdk-ams.app.000000-d0ed-0000-ad00-000000d00ebe"
+      },
+      "attributes": {},
+      "user": {
+        "userId": "amzn1.account.AM3B227HF3FAM1B261HK7FFM3A2"
+      }
+    },
+	"context": {
+		"System": {
+			"application": {
+				"applicationId": "amzn1.echo-sdk-ams.app.000000-d0ed-0000-ad00-000000d00ebe"
+			},
+			"user": {
+				"userId": "amzn1.account.AM3B227HF3FAM1B261HK7FFM3A2",
+				"accessToken": "ae312e92d87d7b4e7648b19a08f2966a831a59de"
+			},
+			"device": {
+				"deviceId": "amzn1.ask.device.123456789",
+				"supportedInterfaces": {}
+			},
+			"apiEndpoint": "https://api.amazonalexa.com",
+			"apiAccessToken": "123456789"
+		}
+	},	
+  "request": {
+    "type": "CanFulfillIntentRequest",
+    "requestId": "amzn1.echo-api.request.e510e005-c518-44c8-930d-746c84e787da",
+    "intent": {
+      "name": "PlaySound",
+      "slots": {
+        "Sound": {
+          "name": "Sound",
+          "value": "crickets"
+        }
+      }
+    },
+    "locale": "en-US",
+    "timestamp": "2018-10-18T09:16:28Z"
+  }
+}