WEBVTT 00:00.020 --> 00:03.470 Okay, it's time to fire up the debugger and see what's going on. 00:03.470 --> 00:09.650 Now, we did give ourselves a clue by giving ourselves different error messages depending on where it 00:09.650 --> 00:14.330 got to in the process, and this is the message we got back from the 400 seconds. 00:14.330 --> 00:20.990 So if we go back to our code and we take a look at the payments controller, then we can see that it's 00:20.990 --> 00:24.950 list line problem creating payment intent which matches. 00:24.980 --> 00:25.460 Oh no. 00:25.460 --> 00:28.730 In fact it's a problem updating the basket with the intent. 00:29.090 --> 00:34.280 Ah, so I think what's going on here is that our basket didn't get updated. 00:34.280 --> 00:35.390 It stayed the same. 00:35.390 --> 00:41.660 So when we got to list line the save changes this was zero, which means we didn't have any changes 00:41.660 --> 00:43.100 to save into our database. 00:43.100 --> 00:45.890 So that request would have actually worked. 00:45.890 --> 00:48.410 And we can confirm this in the stripe dashboard. 00:48.410 --> 00:53.960 Actually, if I refresh this page, then what we should find is that that amount has increased to 300 00:53.990 --> 00:56.330 because stripe is separate to our database. 00:56.330 --> 01:00.930 And sure, we can see that's 300, but it's incomplete. 01:01.080 --> 01:02.910 So what do we do about this then? 01:02.910 --> 01:06.990 Because we do need to save changes if there have been changes. 01:06.990 --> 01:12.840 But if we already have the payment intent ID, then we do not set it with a new intent ID so there's 01:12.840 --> 01:13.830 no change there. 01:13.860 --> 01:15.990 Same goes for the client secret. 01:15.990 --> 01:21.180 But then we've got this call to save changes to our API. 01:21.210 --> 01:24.630 So I think we know what the problem is and we'll deal with that soon. 01:24.630 --> 01:28.920 But let's add a breakpoint inside our payments controller. 01:28.920 --> 01:34.230 Let's take the opportunity to see what's happening as we update a payment intent. 01:34.710 --> 01:39.420 So I'm going to go back and I'm going to restart my API regardless. 01:40.620 --> 01:44.100 And I'll just use control R to restart it before I start the debugger. 01:44.100 --> 01:49.140 I'd prefer not to be any hangovers from hot reloading, although I don't think there would be on this 01:49.140 --> 01:50.550 occasion anyway. 01:50.820 --> 01:55.080 And once it has restarted, let's go and attach the. 01:55.290 --> 02:00.900 I'll close the others Verse down and just keep this one open and we'll go and attach our debugger to 02:00.930 --> 02:01.470 the process. 02:01.470 --> 02:02.850 So I've got the dotnet core attached. 02:02.850 --> 02:10.650 I'll hit the play button, search for API, click on API and let the debugger start up. 02:11.250 --> 02:14.910 And I'll head back to postman and let's go and add. 02:14.940 --> 02:18.750 I'll just keep adding an additional one of these items to the basket. 02:18.750 --> 02:23.550 So now that's going to raise the price to 400. 02:23.910 --> 02:26.070 And I've still got an old breakpoint in here. 02:26.070 --> 02:27.300 So I'm just going to play this request. 02:27.300 --> 02:29.070 I didn't want to stop on this one. 02:29.070 --> 02:34.440 So I just hit play and go back to postman so that I get the item added to the basket. 02:34.470 --> 02:39.630 Now we've got the quantity of three, and then I'll go and click the create Payment intent. 02:39.630 --> 02:45.870 Click send and off we go to our code inside the debugger. 02:45.870 --> 02:48.030 So this is going to go and get our basket. 02:48.030 --> 02:53.970 If we go and step over this then we can see inside here we have our baskets. 02:53.970 --> 02:59.890 We've already got the client secret and the payment intent, and we've got our item inside here, which 02:59.890 --> 03:01.000 is a quantity of three. 03:01.030 --> 03:01.870 Great. 03:01.870 --> 03:06.730 And we'll step over the intent or step over the basket equals null. 03:06.730 --> 03:10.060 And then we've got our code to go and get our payment intent. 03:10.090 --> 03:13.840 Let's use step inside so that we get taken to our payment service. 03:13.870 --> 03:15.310 On this occasion. 03:15.310 --> 03:18.640 And step over and step over again. 03:18.640 --> 03:20.860 This will give us our payment intent service. 03:20.860 --> 03:21.910 That's fine. 03:22.150 --> 03:25.030 This is going to create a new empty payment intent. 03:25.060 --> 03:25.510 Okay. 03:25.540 --> 03:26.710 That's fine as well. 03:26.740 --> 03:28.270 Work out our subtotal. 03:28.270 --> 03:36.100 If we take a look at this one and hover over the subtitle we can see that's for 500 0 or $450. 03:36.100 --> 03:40.570 And that should mean our delivery fee is going to be zero, which it is. 03:40.810 --> 03:45.370 And we should step over this one, this if statement and go on to the update one. 03:45.370 --> 03:52.300 So we do and we go to the else statement which is going to update our payment intent with its options. 03:52.300 --> 03:56.650 And if we take a look at the options, then there's a whole bunch of options we can send up with this. 03:56.650 --> 03:58.810 But our needs are quite simple. 03:58.810 --> 04:01.450 Just the amount is all we're interested in there. 04:01.450 --> 04:11.320 And then we can step over again and again and go back to our payments controller now that we have the 04:11.320 --> 04:12.550 payment intent. 04:12.550 --> 04:14.440 So these are the problematic lines. 04:14.440 --> 04:21.160 If we go and step over this then our basket isn't going to be updated by anything that we do here. 04:21.160 --> 04:26.170 If we do take a look, we can already see that we have these values inside our basket. 04:26.170 --> 04:34.540 So if we step over this and step over this, then nothing changes inside this entity. 04:34.540 --> 04:39.280 So what are our options then for this. 04:39.280 --> 04:44.470 Well we could use a conditional before we get to the saving of the changes. 04:44.470 --> 04:50.530 If we do have the payment intent ID and the client secret, then there's no need to call this line because 04:50.560 --> 04:51.920 this line gives us the problem. 04:51.920 --> 05:01.070 If I step over this line, then what we see as the results is false, because we haven't saved any changes 05:01.070 --> 05:02.600 into our database. 05:02.600 --> 05:08.720 So perhaps a conditional is the approach we can take here, and what we'll do to check to see if we 05:08.720 --> 05:10.190 should save changes. 05:10.190 --> 05:17.060 We can use the Entity Framework change tracker to see if there are any changes that could be saved in 05:17.060 --> 05:20.030 memory, and then we can call our save changes method. 05:20.030 --> 05:23.480 So just above the results here I'll add an if statement. 05:23.480 --> 05:27.230 And we will use the context change tracker. 05:27.230 --> 05:30.050 And we'll use its has changes method. 05:30.050 --> 05:39.110 And if it does then we'll use our two statements here to save the changes into the database. 05:39.110 --> 05:46.760 And if not then we're going to skip over that and just return the basket DTO as it is. 05:46.760 --> 05:53.870 So if we go back and test this, in fact, let's just use control R just in case Hot Reload is playing 05:53.870 --> 05:54.740 up. 05:55.670 --> 06:01.250 And I'll go back to postman and we'll just repeat the request to add an item to the basket. 06:01.250 --> 06:04.430 So I'll click send and we get the 201 created. 06:04.430 --> 06:09.350 And I've gone up to quantity of six because I was doing a bit of off screen troubleshooting. 06:09.350 --> 06:13.130 And we're returning the client secret and the payment ID. 06:13.340 --> 06:19.940 And what we should see if we go back to stripe is we now have an updated payment intent ID in my case 06:19.940 --> 06:21.620 $750. 06:21.620 --> 06:24.650 So that's the outcome that we're hoping for. 06:24.680 --> 06:28.460 And we've now set up the payment intent system on our API server. 06:28.460 --> 06:34.520 So the next step and the more significant steps in what we're doing inside this section is on the client 06:34.520 --> 06:34.910 side. 06:34.910 --> 06:41.210 And we're going to set up our checkout and use all the stripe goodies that we get related to payments 06:41.210 --> 06:45.680 and addresses, so that we can make a payment for this order. 06:45.680 --> 06:48.080 And we'll start taking a look at that next.