WEBVTT 00:03.730 --> 00:04.630 Hated everyone. 00:04.700 --> 00:09.760 Fischer And in this video, we're going to create a very simple, basic route which returns a simple 00:09.760 --> 00:10.120 string. 00:10.120 --> 00:11.740 It can return an object as well. 00:11.740 --> 00:12.790 Eventually it will. 00:12.820 --> 00:14.980 Now, this will serve to purposes. 00:14.980 --> 00:19.270 The first one, obviously, we are going to learn how to write the documentation for it, but it will 00:19.270 --> 00:24.100 also give you an opportunity to explore the documentation of EXPRESS because we'll be handling multiple 00:24.100 --> 00:27.780 requests as well as we'll be handling a multiple responses as well. 00:27.790 --> 00:32.620 A lot of data is going to come into our servers and a lot of data will be going out of the servers in 00:32.620 --> 00:38.290 multiple formats strings, objects, arrays, files, a whole lot of things that are going to be there. 00:38.290 --> 00:44.110 So please don't be shy, go on to the Express documentation and just go through a lot of stuff into 00:44.350 --> 00:45.400 request and response. 00:45.400 --> 00:49.390 It's one of the most easiest library to understand after this course, of course. 00:49.390 --> 00:51.310 So make sure to keep an eye on that. 00:51.550 --> 00:56.170 Now, moving on, let's go into the index and there are a couple of things that we'll be doing. 00:56.170 --> 01:01.750 The first thing that we're going to do is I will be creating a simple array and now this array is going 01:01.750 --> 01:02.650 to be later on use. 01:02.650 --> 01:06.640 So make sure you don't use constant this one because we'll be modifying this array. 01:06.760 --> 01:11.470 Let's go ahead and call this one as simply courses because this is going to be an array of courses. 01:11.470 --> 01:14.230 Now inside this courses, I'll have an object. 01:14.230 --> 01:16.930 Now inside this object, let's add a couple of properties. 01:16.930 --> 01:21.910 For example, we'll be putting up ID, which will be one one and make sure you also follow closely in 01:21.910 --> 01:22.510 this one. 01:22.660 --> 01:24.460 Once you are done with this, you can change anything. 01:24.460 --> 01:26.200 But right now, please follow closely. 01:26.200 --> 01:28.540 This one will be calling this one as name. 01:28.540 --> 01:32.710 So we're going to call this one as a learn, react, react. 01:32.720 --> 01:35.950 JS And after that we'll be going for a price. 01:36.220 --> 01:38.740 Now, for the price, we'll be just saying to 99. 01:38.740 --> 01:40.120 Now I have a variety here. 01:40.120 --> 01:41.970 We have string and we have some numbers. 01:41.970 --> 01:42.880 So all going on. 01:42.880 --> 01:44.500 Let's go ahead and put up a comma. 01:44.500 --> 01:48.400 Now, I need a couple of copies of this, so I'm going to go ahead and bring two more. 01:48.520 --> 01:49.930 And again, I'm using shortcut. 01:49.930 --> 01:51.250 I'm kind of used to with that. 01:51.250 --> 01:54.790 In case you are not just make sure you go ahead and copy paste that. 01:54.790 --> 01:56.110 So this one is going to be two too. 01:56.140 --> 01:57.460 This one is going to be three. 01:57.460 --> 01:57.970 Three. 01:58.060 --> 01:59.590 Let's go ahead and add some more. 01:59.590 --> 02:02.440 So we're going to say, hey, probably you want to learn Angular. 02:03.620 --> 02:04.500 There we go. 02:04.520 --> 02:08.240 Or probably you want to learn something else, maybe Django or something else. 02:08.330 --> 02:13.040 Let's change the pricing to probably 399, 499, something like that. 02:13.040 --> 02:13.880 Whatever you want. 02:14.060 --> 02:15.140 Doesn't really matter. 02:15.170 --> 02:17.210 We will be using this array later on. 02:17.210 --> 02:19.260 So right now you can just keep it as it is. 02:19.280 --> 02:24.090 We'll still keep our route as it is, but we need to create something different of a route. 02:24.110 --> 02:26.870 So let's go ahead and copy paste this one. 02:27.440 --> 02:33.080 Now, one important thing is that we have defined our server as the URLs up here. 02:33.080 --> 02:38.870 So inside the server we have mentioned the URL that we are going to use is going to be V one, so http 02:38.900 --> 02:42.200 and then localhost 4000 API and the version. 02:42.200 --> 02:46.890 So make sure this is not just a fictitious URL or this is just not an ornament there. 02:46.910 --> 02:49.040 This will be used while making the request. 02:49.040 --> 02:50.390 That's why we call them as server. 02:50.390 --> 02:52.520 So don't think that these are just ornaments. 02:52.850 --> 02:55.310 Whatever you are going to define is automatically going to come. 02:55.310 --> 02:57.020 And no, it doesn't work like that. 02:57.290 --> 02:58.370 Okay, moving on. 02:58.970 --> 03:02.720 So as we have mentioned that this is going to be API slash V one. 03:02.720 --> 03:04.070 So we have to mention that. 03:04.070 --> 03:09.830 And then if somebody hits the root of AE, then we are going to simply send a response which says hello 03:09.830 --> 03:10.820 from AE. 03:11.420 --> 03:14.350 So hello from AE Docs. 03:14.360 --> 03:14.620 Yeah. 03:14.660 --> 03:16.190 Just to make it a little bit different. 03:16.790 --> 03:19.160 You can also send most of the other objects as well. 03:19.160 --> 03:21.770 But right now this is all what we want to do. 03:22.100 --> 03:26.270 Let's go into the swagger and see that how we actually can write all of this. 03:26.390 --> 03:31.520 Now, one thing that confuses a lot of people that no matter what kind of roots you are doing, maybe 03:31.520 --> 03:36.950 for products, for users, for orders, for categories, for courses, whatever, it all comes into 03:36.950 --> 03:39.320 just one umbrella, which is known as paths. 03:39.320 --> 03:39.680 Yes. 03:39.680 --> 03:42.380 This is the only drawback of the yaml. 03:42.470 --> 03:43.010 Yes. 03:43.010 --> 03:47.460 There are some CLI tools given by the YAML to actually combine all of the YAML files. 03:47.480 --> 03:48.670 A lot of people do that. 03:48.680 --> 03:53.150 That will be a little bit out of the scope of this course because we just need the bare minimum basics 03:53.150 --> 03:54.770 and you can explore that on your own. 03:55.010 --> 04:01.370 Now how this path is going to look like, I'll say that slash AE because remember in the servers I have 04:01.370 --> 04:05.360 already mentioned, it's slash slash API slash V1. 04:05.360 --> 04:06.920 So that's what we are following up here. 04:07.040 --> 04:12.050 Now notice here, once I have given that this is going to be my root, then I have to mention that what 04:12.050 --> 04:14.780 kind of root this is going to be, this is going to be get or post. 04:14.780 --> 04:18.830 And for each of that path, if I want to write, get post, I have to go through like this. 04:18.830 --> 04:22.760 So if I have to get all the properties of get, then if I have a post here. 04:22.760 --> 04:26.360 So I'll come back and write post up here and all the further properties down there. 04:26.390 --> 04:28.970 Right now let's go ahead and worry just about the get. 04:29.150 --> 04:31.910 Now inside the get, I will add a summary. 04:31.910 --> 04:35.910 So let's go ahead and add a summary in the writing documentation part. 04:35.930 --> 04:38.420 This is really tricky and you might want to follow a standard. 04:38.420 --> 04:40.280 It's up to you how you want to say that. 04:40.280 --> 04:49.910 We're going to simply say return a returns agreed message from AE. 04:49.940 --> 04:51.620 Okay, that sounds a good summary. 04:51.620 --> 04:56.000 Now after that comes up is the most important part, which is responses. 04:56.120 --> 04:59.630 Now responses can be multiple, the responses can be 200. 04:59.660 --> 05:00.830 Yes, you can write it in quotes. 05:00.830 --> 05:02.660 You can write it in without code as well. 05:02.690 --> 05:09.380 There can be multiple responses like 300, 400, maybe you want to describe 500 as well. 05:09.380 --> 05:12.200 It's all up to you what you define and how you're going to define. 05:12.200 --> 05:14.870 Let me define one here and then show you. 05:14.870 --> 05:18.350 Then I'll remove the 500 because it's eventually going to get too much. 05:18.500 --> 05:19.040 Okay. 05:19.400 --> 05:21.080 The first thing is description. 05:21.080 --> 05:23.750 So you go ahead and simply say what is going to be the description? 05:23.750 --> 05:27.440 All good and success. 05:27.440 --> 05:30.260 Usually this is like little bit more of a description type. 05:30.260 --> 05:31.480 So this is what we do. 05:31.490 --> 05:36.110 Now, apart from this, you can also mention that what is the type of content that will be coming up 05:36.110 --> 05:36.620 here? 05:37.340 --> 05:42.380 So let's go ahead and say that this content is going to be coming up, is going to be a type of application 05:42.380 --> 05:49.130 slash JSON, although we are not sending the JSON, but we will modify our route in a minute and then 05:49.130 --> 05:50.960 we can also define our scheme. 05:50.960 --> 05:52.940 Now this not scheme schema. 05:53.390 --> 05:59.000 So what the schema is going to be that I am returning a type of string, we will have multiple eventually. 05:59.000 --> 06:00.350 So don't do worry on that part. 06:00.350 --> 06:03.230 And we can also define an example here. 06:05.320 --> 06:08.170 So for example, let's just say my string. 06:08.650 --> 06:13.690 As soon as I saved this, I would like to actually copy paste this description to others as well, so 06:13.690 --> 06:15.640 that we have at least something to look on. 06:16.120 --> 06:17.320 And there we go. 06:17.590 --> 06:19.270 And this one is going to be. 06:21.160 --> 06:28.930 Bad request and this one is going to be internal server error. 06:29.860 --> 06:30.790 Quite a lot of stuff. 06:30.790 --> 06:35.980 So let's go up here and let me go back onto the browser swagger and hit a reload. 06:36.250 --> 06:39.550 Now you can see that this is the first one that we have seen so far. 06:39.580 --> 06:40.960 This is how it looks like. 06:40.960 --> 06:42.820 So we can see we have a get request. 06:42.820 --> 06:44.650 It will be on the path slash ae. 06:44.650 --> 06:47.440 But remember right now you haven't computed this one. 06:47.440 --> 06:52.450 So if you try to just go ahead and try it out, it's not going to probably not going to work much because 06:52.450 --> 06:55.390 you're you are is undefined and this is not how it's going to work. 06:55.390 --> 07:01.660 So you have to every time select the V one again it's not coming up so v one and then you have to say 07:01.660 --> 07:03.820 that, hey, I have to use the HTTP. 07:03.820 --> 07:05.680 You can also mention the default one. 07:05.920 --> 07:08.680 We will be seeing that how we can do that later on. 07:08.950 --> 07:10.330 Right now, this is all what we have got. 07:10.330 --> 07:12.370 As soon as I go ahead and hit cancel first. 07:12.370 --> 07:17.290 So you need to hit try out every single time and hit click on execute there. 07:17.290 --> 07:21.700 Now this request goes to http localhost API V1 and slash AE. 07:21.700 --> 07:23.380 So this is the part that is coming up. 07:23.380 --> 07:29.650 Our message is also coming up nicely returns a greeting message from AE and we get a response body which 07:29.650 --> 07:31.630 says hello from the AE docs. 07:31.630 --> 07:33.460 We also see some of the response header. 07:33.460 --> 07:38.740 Remember in the docs of Express, I mentioned that you can also set some headers via the back end. 07:38.740 --> 07:41.620 This is exactly how you do this and this is how you get it. 07:41.650 --> 07:44.110 Now in here we see that all good success. 07:44.110 --> 07:47.350 These are response code that what is going to happen and how it works. 07:47.350 --> 07:52.240 Since in the response code we have mentioned that the media type that is coming up is the application 07:52.240 --> 07:52.600 JSON. 07:52.600 --> 07:55.990 That's why it's coming up and all the basic schemas. 07:55.990 --> 07:59.230 Now good thing is notice here in the example value there is a schema. 07:59.230 --> 08:03.970 You can click on this and it will give you that exact schema that is coming up like string and example 08:03.970 --> 08:05.080 is going to be a string. 08:05.080 --> 08:09.190 So this actually gives the user an idea that what kind of response I'm going to get back. 08:09.190 --> 08:13.990 Of course the user can actually execute, but writing a schema is always a good idea in case your application 08:13.990 --> 08:16.660 is too much heavily driven on this entire thing. 08:16.900 --> 08:20.710 Now coming up, back to the part, we will be working on it a little bit. 08:20.710 --> 08:22.600 One more thing I would like to mention here. 08:23.260 --> 08:29.320 You can see that we have this default AE So how you can change this default, this is the basic and 08:29.320 --> 08:32.710 I know this is not too much visible here, but this is all grayed out. 08:32.710 --> 08:36.070 So this is how you actually group all of the requests together. 08:36.070 --> 08:39.310 So what you can do, you can actually tag these requests. 08:39.310 --> 08:43.660 So just after the get request, I can go ahead and hit the tag. 08:43.660 --> 08:48.490 So I'm going to say tags and let's go ahead and call this one as. 08:49.650 --> 08:50.400 String. 08:51.030 --> 08:54.720 Now you can get this tag onto multiple other paths as well. 08:54.720 --> 08:59.760 And as soon as you are going to do this and let me hit a refresh and now notice a string. 08:59.760 --> 09:05.640 So all the other requests that are related to this particular tag string, they will not go further 09:05.640 --> 09:10.260 down in the road, but actually automatically will come up into this group, which is the string group. 09:10.290 --> 09:15.660 I will also explain this a little bit more in depth later on, but I guess this is all it for now. 09:15.660 --> 09:17.790 And let's go back into the next video.