WEBVTT 00:03.760 --> 00:05.230 Hated everyone had their share. 00:05.230 --> 00:09.430 And in this video, we're going to talk a little bit briefly about the database connections and what 00:09.430 --> 00:11.290 all the things you have to worry about. 00:11.380 --> 00:16.030 Now, if you go back on to the presentation, remember once we were discussing about all of this a little 00:16.030 --> 00:21.190 while ago, I told you that database is always on different continent. 00:21.190 --> 00:24.010 As long as you remember this, everything will be all good. 00:24.010 --> 00:27.340 But you saw that it is so easy to actually forget all of this. 00:27.340 --> 00:30.040 That's why I have created a dedicated video on this one. 00:30.040 --> 00:32.710 What do I mean by database is on a different continent. 00:32.710 --> 00:36.190 It means it is going to take some time while fulfilling the operation. 00:36.190 --> 00:39.250 And can you see on the line 20 we saw that existing user. 00:39.250 --> 00:42.790 We are grabbing this and we are able to just say user find one. 00:42.790 --> 00:47.800 Now although this operation is going to be really faster, but there is no guarantee that this is going 00:47.800 --> 00:49.300 to happen instantaneously. 00:49.300 --> 00:53.590 Your database can be on another continent and it can take some time to work with that. 00:53.590 --> 00:56.890 So such kind of requests should be actually followed by a wait. 00:56.920 --> 01:01.150 Now, as soon as you are going to use Evade, that means it's not a synchronous operation, it's an 01:01.150 --> 01:02.230 asynchronous operation. 01:02.230 --> 01:07.240 But as soon as you save this, this will create a problem in the crashing of your app that, Hey, why 01:07.240 --> 01:08.410 are you using a wait? 01:08.770 --> 01:10.240 Where is the async functionality? 01:10.240 --> 01:13.300 So this entire method should be a sync type. 01:13.300 --> 01:16.210 So we're going to go ahead and we're going to use a sync. 01:17.260 --> 01:18.130 There we go. 01:18.160 --> 01:19.390 Now, is this okay? 01:19.630 --> 01:21.550 Yes, for as of now, this is okay. 01:21.580 --> 01:24.340 This is not going to bother you any further down the road. 01:24.340 --> 01:28.000 But you can also see that this actually returns a promise. 01:28.000 --> 01:30.070 So there is a promise issue here. 01:30.070 --> 01:36.130 So whenever these kinds of request actually is being sent onto the database itself, a promise is being 01:36.130 --> 01:36.970 received back. 01:36.970 --> 01:40.810 Now, promise can go success and can go failure as well. 01:40.900 --> 01:45.550 And in case you remember, we actually saw this in the documentation, but I kind of glimpse through 01:45.550 --> 01:46.120 over it. 01:46.150 --> 01:52.360 So if you look up here, so a little bit on to the query page, notice it says these execution. 01:52.360 --> 01:55.960 So if you want to execute this query right now, you just want to use this one. 01:55.960 --> 02:00.700 But if we'll dig up a little bit more onto these documentation, they're going to find that always and 02:00.700 --> 02:01.480 always. 02:01.660 --> 02:03.400 This actually fires up a promise. 02:03.400 --> 02:08.740 Now you can actually configure the promise you like, whether you like any special type of promises 02:08.740 --> 02:09.880 or you want to use the default one. 02:09.880 --> 02:10.630 That's up to you. 02:10.660 --> 02:12.250 Not going too much in detail of that. 02:12.250 --> 02:18.430 But remember, a promise is written here because this should be promised or you have to wrap it up into 02:18.430 --> 02:19.660 a tri catch block. 02:19.660 --> 02:23.170 So we are definitely missing some of the optimization that we can do. 02:23.740 --> 02:24.220 That is all. 02:24.220 --> 02:24.550 Okay. 02:24.580 --> 02:28.240 We will discuss that and figure it out as we move on into the next sections. 02:28.600 --> 02:33.070 But another thing is right now we are not connected to the database, so how are we going to do that? 02:33.070 --> 02:38.620 The connecting of the database, first thing we are going to do is we are going to configure our DMV 02:38.620 --> 02:42.850 because this is where the the URL of the database should be written up. 02:42.850 --> 02:49.300 So we're going to go ahead and say Mongo DB, underscore URL, call it UI or you are totally up to you. 02:49.330 --> 02:52.300 Now let me bring up my MongoDB compass. 02:52.300 --> 02:57.940 So we'll be using this one in case you are using Atlas, the online version of DB, then go ahead and 02:57.940 --> 03:03.820 grab that URL in case which I personally recommend is install MongoDB locally, then you can just go 03:03.820 --> 03:06.460 ahead and hit the connect and it will automatically connect for you. 03:06.460 --> 03:10.810 The reason it was able to connect you so easily because in the settings all the settings are already 03:10.810 --> 03:11.290 there. 03:11.500 --> 03:16.690 And here you can see these are the only database we are going to call this one as AE ought to make it 03:16.690 --> 03:17.800 a unique database. 03:17.800 --> 03:20.140 So how we actually go ahead and define that. 03:20.140 --> 03:27.160 So the URL for the local host database is mongo colon slash slash, just like we have HTTPS or HTTP. 03:27.190 --> 03:34.090 And then you can go ahead and pass on either localhost or you can just simply say 1 to 7 .0.0.1, that's 03:34.090 --> 03:35.500 again, a localhost URL. 03:35.500 --> 03:38.230 And then we're going to call this one as at AE. 03:38.230 --> 03:42.910 So this is all you have to do now at the time of deploying, we can go ahead and replace this with the 03:42.910 --> 03:46.660 Atlas or whatever the URL is there, wherever your database is hosted. 03:46.660 --> 03:47.470 That's it. 03:47.770 --> 03:48.210 Okay. 03:48.880 --> 03:52.140 Moving on now let's go into the config and database JS. 03:52.150 --> 03:56.980 And you guessed it right, this is exactly where we'll write the connection of the database string. 03:57.010 --> 03:58.330 Can we write it just like that? 03:58.330 --> 03:59.290 No, of course we cannot. 03:59.290 --> 04:02.770 We need to go in the documentation section and see how it is being done. 04:02.770 --> 04:07.420 So let's go into the Quickstart and we can see that all this is going on. 04:07.420 --> 04:10.300 But let's go ahead and see how we can connect. 04:10.300 --> 04:13.390 So connections are there and there we go. 04:13.390 --> 04:18.640 So it says Mongoose, Dot Connect, and you can just use the connection just like that, or you can 04:18.640 --> 04:19.570 go ahead and work with that. 04:19.570 --> 04:20.590 So this is pretty easy. 04:20.590 --> 04:23.380 They say this is just a one liner Mongoose dot connect. 04:23.980 --> 04:28.420 Technically, yes, this is one liner and they give you example of MongoDB call local localhost. 04:28.420 --> 04:32.210 And again, I forgot that we need to put up this port as well. 04:32.210 --> 04:33.880 I almost forgot that. 04:33.910 --> 04:40.450 Okay, let's go back into the DMV and we have to say colon 27017. 04:40.450 --> 04:46.960 This is a default port of MongoDB so don't scare get get scared off on that OC this is okay, we can 04:46.960 --> 04:51.430 definitely use that or the link from the online version that is okay. 04:51.430 --> 04:55.930 But let me tell you a little bit more on that, that how this should actually be done. 04:56.320 --> 05:01.570 Let's go back and moving into the database is the first thing obviously we need. 05:01.610 --> 05:02.000 Mongoose. 05:02.000 --> 05:06.140 So let's go ahead and say, hey, mongoose, that is going to be required. 05:06.530 --> 05:08.320 And we're going to say Mongoose. 05:08.330 --> 05:09.020 There we go. 05:09.710 --> 05:14.900 Once Mongoose is there, then we also need this variable that we have just declared in the environment 05:14.900 --> 05:15.290 variable. 05:15.290 --> 05:17.090 So let's also structure that. 05:17.210 --> 05:24.880 So that will be coming up from process dot, E and V and what did we call our variable MongoDB URL? 05:24.890 --> 05:27.800 Copy that and paste it up here. 05:29.300 --> 05:36.620 Now the documentation says that you go ahead and simply say Mongoose, dot connect and there is no problem 05:36.620 --> 05:36.950 in that. 05:36.950 --> 05:39.050 This is exactly how we should be doing it. 05:39.920 --> 05:42.130 So we're going to save MongoDB URL. 05:42.410 --> 05:46.970 But in addition, if you're going to save this, you are going to notice that it asks you to provide 05:46.970 --> 05:49.390 a couple of options, the connection options. 05:49.400 --> 05:54.230 Now, these connection options are pretty common, known everywhere on every StackOverflow and every 05:54.230 --> 05:54.670 one. 05:54.680 --> 05:59.810 The first one is actually use new URL parser. 05:59.810 --> 06:03.620 So previously MongoDB was using some kind of different parser. 06:03.620 --> 06:08.060 They updated it and now they want you to pass on the flag because they are legacy compatible. 06:08.060 --> 06:12.380 So that is why we need to use the modern parser that we are working on now. 06:12.380 --> 06:20.270 Also similar one more feature got update or one more settings got update which is use unified. 06:21.220 --> 06:22.340 Topology. 06:22.360 --> 06:27.640 Now there are a couple of more settings that you can go with that probably like use the new index and 06:27.640 --> 06:28.060 all of that. 06:28.060 --> 06:32.920 We don't definitely need this in this one, but we are going to figure them out later on. 06:32.950 --> 06:37.630 Now, again, sometimes it's a little bit easy to get a typo in that, so make sure you keep an eye 06:37.630 --> 06:38.100 on that. 06:38.110 --> 06:39.460 Hopefully I didn't made that. 06:39.730 --> 06:44.920 Now, as I told you, everything that you do with the Mongo or mongoose, they are always a promise. 06:44.920 --> 06:45.610 So promise. 06:45.610 --> 06:46.370 What does it return? 06:46.390 --> 06:48.670 It returns a dot, then. 06:49.720 --> 06:50.350 There we go. 06:50.350 --> 06:50.920 Just like that. 06:50.920 --> 06:54.430 And it also returns a dot catch because there can be a problem here. 06:54.550 --> 06:56.620 So what happens when we get a dot? 06:56.620 --> 07:00.520 Then let's go ahead and separate them on the separate line so that it's easier for us. 07:01.150 --> 07:05.260 So in the case of Dot catch, then obviously we are going to receive an error. 07:05.260 --> 07:08.080 So let's go ahead and handle that part just like this. 07:08.260 --> 07:17.110 And we're going to simply go ahead and first log this out and we are going to say that DB connection 07:17.110 --> 07:18.130 failed. 07:18.160 --> 07:18.910 There we go. 07:19.270 --> 07:23.830 Also, we need to log these errors, so let's go ahead and log them properly. 07:23.830 --> 07:25.090 So let's go ahead and dump them. 07:25.090 --> 07:25.870 All of that. 07:26.200 --> 07:27.880 Not a good strategy in the production. 07:27.880 --> 07:32.380 We want to have a separate error between the production as well as in the development environment. 07:32.380 --> 07:34.300 We can talk about that later on. 07:34.300 --> 07:38.470 And finally, the most important is process dot exit. 07:38.620 --> 07:43.620 Now again, the documentation doesn't give you in detail the depth of it because it is known. 07:43.630 --> 07:48.070 It should be known that, hey, there's going to be a promise and you need to handle the promises accordingly. 07:48.100 --> 07:53.830 We will take care of the things in the next project that how properly we can have these things and notice. 07:53.830 --> 07:57.100 On top of that there needs to be a sync one here. 07:57.100 --> 08:02.170 It is not required, but in all of the other cases it needs to be an async request with the promises 08:02.170 --> 08:03.820 or the TRICARE wrapper. 08:04.000 --> 08:08.170 Now, if everything goes right, then we are going to go ahead and simply, simply log a message that, 08:08.170 --> 08:10.000 hey, database connection is all good. 08:10.330 --> 08:14.470 So we're going to simply throw up that DB connected. 08:15.940 --> 08:17.500 Successfully. 08:17.830 --> 08:18.640 There we go. 08:18.640 --> 08:19.870 And we don't need this. 08:21.100 --> 08:21.580 Save this. 08:21.580 --> 08:22.540 So this is all done. 08:22.540 --> 08:29.230 But again, this is not all we have to do because we won't be using this into the DVD as we would be 08:29.230 --> 08:32.620 rather throwing up into a separate folder. 08:32.620 --> 08:35.500 So notice we are not holding this entire thing into available. 08:35.500 --> 08:36.670 Now we need to do that. 08:36.670 --> 08:41.560 So what we can do, easiest thing is let's just cut this out, all of this and we're going to go ahead 08:41.560 --> 08:46.180 and directly write exports dot connect because there will be not too much of the variables into this 08:46.180 --> 08:46.450 file. 08:46.450 --> 08:51.430 We can directly say that, hey, this is a method connect that I'm throwing this out, this is how this 08:51.430 --> 08:56.710 method looks like and we can go ahead and paste everything inside that. 08:56.710 --> 08:57.550 So there we go. 08:57.850 --> 09:02.290 Now anybody can import this connect and can start connecting with the database. 09:02.290 --> 09:05.830 So let's go ahead and use it into app dogs now in the app. 09:06.010 --> 09:11.290 JS One important thing, we don't need to hold this connect this connect into a variable. 09:11.290 --> 09:13.900 We can just run it directly as soon as it comes in. 09:14.020 --> 09:15.640 So let's go ahead and do that. 09:15.640 --> 09:20.530 So once Express is required, all of that, we can actually do it at the top. 09:20.800 --> 09:25.900 We're going to go ahead and say Hey required and make sure your dot inv is required as first because 09:25.900 --> 09:28.990 it's going to bring in MongoDB URL in case it needs it. 09:29.470 --> 09:32.470 So we're going to go ahead and save from the current directory. 09:32.470 --> 09:40.090 Let's go into config and inside that we are going to have a database JS and it has a method dot connect 09:40.090 --> 09:41.740 and just go ahead and run this. 09:41.740 --> 09:46.120 Now again, there can be many other ways you can hold that into a variable and then say that, hey, 09:46.120 --> 09:50.830 I am calling this XYZ and run this totally up to you how you want to do that. 09:50.950 --> 09:55.330 Now notice here it says, hey, crashed because probably there is something wrong in the URL. 09:55.360 --> 10:00.400 So it says invalid string which is mongo and notice it's not mongo. 10:00.400 --> 10:03.490 It is also mentioned up there it is MongoDB. 10:03.490 --> 10:10.120 So again referring to my env files again and this is MongoDB. 10:10.540 --> 10:16.750 Save that and we need to restart because of an E and v files are not being monitored and notice now 10:16.750 --> 10:18.790 it says DB connected successfully. 10:18.880 --> 10:22.120 So again with a little bit of the error, now we are working on that. 10:22.120 --> 10:22.450 Okay. 10:22.450 --> 10:24.100 So now our database connection is done. 10:24.100 --> 10:28.720 But still there are a couple of things you should always keep in mind that this always returns a promise. 10:28.720 --> 10:32.140 In fact, whenever you make a query, this is going to return. 10:32.140 --> 10:34.720 You promise and you need to handle that promise. 10:34.720 --> 10:38.770 Here we are writing absolute the basic one because we need the US thing functionality as well. 10:38.770 --> 10:44.590 So there are a couple of things we can definitely talk about, but that's all moving back onto the presentation 10:44.590 --> 10:46.510 now that what else we have to do. 10:46.510 --> 10:51.310 So we have talked to the database, we have already worked on, already registered, but how we're going 10:51.310 --> 10:53.710 to take care of the password, that is the big question. 10:53.710 --> 10:55.630 And the next question is token generation. 10:55.630 --> 11:01.180 So in the next video, let's talk about what are the points where we can talk, take care of the password 11:01.180 --> 11:03.100 and how we can actually take care of it. 11:03.100 --> 11:05.050 Let's go ahead and catch up in the next video.