WEBVTT 00:00.290 --> 00:05.420 In this lesson, we are going to establish the communication between Alexa and our PC. 00:05.990 --> 00:12.980 In practice, we are going to enable the communication between the Alexa Voice assistant and a web server 00:12.980 --> 00:17.000 on our PC that is going to be provided by Ngrok. 00:17.180 --> 00:22.880 This way our PC will be able to receive messages from the voice assistant and also to process these 00:22.880 --> 00:25.730 messages to actuate the robot accordingly. 00:26.440 --> 00:27.730 To enable this communication. 00:27.730 --> 00:32.980 As I said, we are going to use the Ngrok software, so let's start by downloading it. 00:32.980 --> 00:36.730 So in Google, let's look for Ngrok. 00:37.970 --> 00:43.100 And then let's click on the first one and here you are going to need an account to this website. 00:43.400 --> 00:46.190 So if you don't have yet, please sign up. 00:46.430 --> 00:50.360 Otherwise, if you have it, as in my case, just log in. 00:51.030 --> 00:55.000 And now once we access this web page, let's download. 00:55.020 --> 00:57.990 So let's download Ngrok for Linux. 00:58.170 --> 01:00.810 So this is going to download an archive. 01:01.080 --> 01:08.810 So let's open then the download folder in which it was downloaded and let's extract all the content. 01:08.820 --> 01:12.750 And so now we have ngrok here that is ready to be used. 01:13.200 --> 01:17.550 Now in order to use Ngrok, we need to open a new terminal. 01:18.420 --> 01:22.260 And so let's go to the folder in which we just downloaded Rock. 01:22.530 --> 01:26.970 And so in my case this is the downloads folder. 01:27.300 --> 01:29.280 And then we did the downloads folder. 01:29.280 --> 01:31.710 I downloaded a folder called Ngrok. 01:32.430 --> 01:37.200 And then within this folder we can see that there is an executable called Ngrok. 01:37.290 --> 01:44.430 We can start this executable with the command dot slash followed by the name of the executable that 01:44.430 --> 01:45.660 is Ngrok. 01:45.660 --> 01:50.700 And then we need to configure Ngrok in order to associate it with our account. 01:50.700 --> 01:57.450 So here, as you can see in the point number two, we can copy this command here which contains a key 01:57.450 --> 01:58.940 for your account. 01:58.950 --> 02:01.530 So let's copy the command. 02:03.350 --> 02:05.660 And let's paste it within the terminal. 02:07.020 --> 02:08.760 And so let's press enter. 02:08.760 --> 02:10.890 And this will have saved your key. 02:10.890 --> 02:14.130 And so we'll have activated also your lock account. 02:14.130 --> 02:17.070 And so from now on, we can start using this software. 02:18.220 --> 02:23.170 Now, in order to use it, we can still run the executable. 02:23.320 --> 02:25.060 So andyrock. 02:25.360 --> 02:30.880 And now we need to specify the communication protocol that we want to use for the web server that we 02:30.880 --> 02:31.960 are going to host. 02:32.180 --> 02:34.900 And so let's use the Http protocol. 02:35.080 --> 02:37.030 And now let's also specify the port. 02:37.030 --> 02:41.110 So which is the port of our PC, which we want to open to the outside. 02:41.110 --> 02:46.480 So to the internet and so which is the port that will be able to receive messages from the Amazon. 02:46.480 --> 02:51.400 Alexa assistant, let's say the port number 5000. 02:51.550 --> 02:53.260 So let's press enter. 02:53.260 --> 03:00.580 And now Ngrok will make the port 5000 of our PC so the local host accessible to the external world and 03:00.580 --> 03:01.780 so to the internet. 03:02.350 --> 03:05.260 It also provides us an unique address. 03:05.260 --> 03:11.700 So this one here, this is a unique address that is automatically generated by Ngrok. 03:11.710 --> 03:17.920 And this address is what we need to configure in the Alexa developer console in order to allow the voice 03:18.020 --> 03:20.300 assistant to send messages to our PC. 03:20.870 --> 03:22.550 So let's copy this one. 03:22.580 --> 03:25.220 The one that says Https. 03:25.490 --> 03:27.350 So let's copy this link. 03:27.350 --> 03:32.870 And now let's go back to the Alexa developer console and let's go back to the Arduino bot skill that 03:32.870 --> 03:34.310 we are implementing. 03:34.610 --> 03:40.460 Now let's take this on one side so that we can see the message exchange. 03:40.730 --> 03:47.480 And here let's go to the endpoint section and in the default region in which we inserted a placeholder 03:47.480 --> 03:53.030 address, now we can paste the actual address of our web service. 03:53.030 --> 03:58.700 So the one that Nroc makes available on our PC, let's save the endpoint. 03:59.450 --> 04:00.970 And now let's test this skill. 04:01.010 --> 04:01.610 Communication. 04:01.610 --> 04:05.810 So the communication between the Alexa developer console and our PC. 04:05.900 --> 04:11.290 So this is running on our PC and this is running on the Amazon Alexa servers. 04:11.300 --> 04:14.870 So now let's test the communication between these two systems. 04:15.260 --> 04:17.120 So again, in the test tab. 04:18.170 --> 04:20.870 Let's again activate the skill. 04:21.800 --> 04:23.270 Activate robot. 04:25.610 --> 04:28.640 There was a problem with the requested skills response. 04:28.790 --> 04:33.960 And you can notice that two messages have been printed here in the terminal. 04:33.980 --> 04:40.820 So in the Ngrok console, although these are error messages from the server indicating that it wasn't 04:40.820 --> 04:47.300 able to process the message that it received, this still means that the Alexa console was able to contact 04:47.300 --> 04:55.340 our PC, so was able to send a message to our PC through Ngrok and so through this address here that 04:55.340 --> 04:56.600 ngrok provided. 04:57.280 --> 05:03.210 I now that the Alexa voice assistant can communicate and so can send messages to the web server on our 05:03.210 --> 05:03.540 PC. 05:03.750 --> 05:10.950 We can finally add the logic that processes the messages that Alexa sends us and use their information 05:10.950 --> 05:13.050 to send commands to our robot.