WEBVTT 00:03.910 --> 00:05.310 Hey, did everyone that they share? 00:05.320 --> 00:08.980 And in this video, we're going to have a revision of the JavaScript. 00:09.070 --> 00:12.850 Now, in case you think that you are an absolute pro in JavaScript, you don't need this video, then 00:12.850 --> 00:14.590 you can absolutely skip this one. 00:14.590 --> 00:17.620 This has nothing to do with the course just except one thing. 00:17.950 --> 00:21.360 Let me just walk you through with that one thing and then you'll be absolutely free. 00:21.370 --> 00:22.270 So in the product. 00:22.270 --> 00:26.560 JS What we have done is we have used these dashes inside the enum. 00:26.560 --> 00:31.480 When we are setting up the categories, I later on realize that these dashes can actually give us some 00:31.480 --> 00:31.900 problems. 00:31.900 --> 00:34.750 So I'm going to go ahead and remove all these dashes. 00:34.900 --> 00:39.730 Now, usually you can go ahead in the front end, can use the dashes or even spaces, whatever you like. 00:39.730 --> 00:45.010 But I think when these values are going to come to us, they might create some issues, not compulsory, 00:45.010 --> 00:45.670 but they might. 00:45.670 --> 00:50.770 It was bothering me a little bit because sometimes these dashes and spaces are too much are encoded. 00:50.770 --> 00:51.490 I don't want that. 00:51.490 --> 00:52.300 So that's why. 00:52.540 --> 00:56.710 Okay, so this is the main part of the thing that is about or related with the course. 00:56.710 --> 00:58.930 Now next step is the JavaScript basics. 00:59.110 --> 01:03.280 I have realized that a lot of people don't really understand some of the concept of the JavaScript and 01:03.280 --> 01:05.560 that actually bothers them throughout the course. 01:05.560 --> 01:09.850 In this video, I'll walk you through with one of the such incident, which is throughout the industry 01:09.850 --> 01:12.730 is being used, which is one to replace method. 01:12.730 --> 01:16.660 I will walk you through what happens and how it can be utilized and further more on that. 01:16.840 --> 01:17.360 Okay. 01:17.830 --> 01:21.100 So we're going to first start by having a basic file. 01:21.100 --> 01:24.130 So first let's get a simple file inside the util folder. 01:24.130 --> 01:25.480 It's not going to be useful. 01:25.480 --> 01:30.760 It's going to be a simple new file, which is going to be simply a demo test. 01:31.090 --> 01:36.760 JS Okay, so this is the basic file that we have, and I'm going to be just writing some gibberish code 01:36.760 --> 01:37.150 in this. 01:37.150 --> 01:41.530 These codes are not going to actually run, but this is important for understanding perspective. 01:41.650 --> 01:46.480 Now what we have so far seen that whenever we have modeled something like user or product or whatever, 01:46.480 --> 01:48.640 we have this method of find. 01:48.730 --> 01:51.130 Now in the find so far we have passed on nothing. 01:51.130 --> 01:56.740 That means an empty parenthesis, or sometimes we don't even pass on that when we don't pass on anything. 01:56.740 --> 01:59.410 This means that we are passing in an empty selector here. 01:59.410 --> 02:02.590 Now this is where usually the query goes in of the MongoDB. 02:02.590 --> 02:07.360 In case you remember, we sometimes actually worked on something like this that, hey, when the email 02:07.360 --> 02:12.100 equals to email or something like this, or in this case we were writing just the email. 02:12.130 --> 02:18.010 Now the idea behind that is that if I want to find a user which is having an email of, let's just say 02:18.010 --> 02:22.600 hit at the rate AE dev, it's going to give me all of that. 02:22.600 --> 02:27.820 Now in case if you remember, we used similar kind of property when we were working on the models. 02:28.090 --> 02:29.470 Let me show you that again. 02:29.470 --> 02:35.410 Inside the user controller for the manager especially, we wrote that I want to find everybody who's 02:35.410 --> 02:36.670 role is user. 02:36.670 --> 02:40.780 So I can definitely go ahead and find the user based on this query. 02:40.900 --> 02:46.140 Now so far we have seen that I can find all the users who are having role some particular email, very 02:46.190 --> 02:48.280 restrictive on that or everybody like that. 02:48.370 --> 02:50.800 But there is a little bit more to it. 02:50.800 --> 02:53.020 Let me show you that on the documentation. 02:53.020 --> 02:57.580 If you will read the MongoDB manual itself, you are going to see that we have some of the comparison 02:57.580 --> 02:59.020 query operator as well. 02:59.050 --> 03:06.160 These query operator are remarkably helpful in all of the cases they have equals greater than greater 03:06.160 --> 03:15.880 than equal to in then less than less than equal to then we have got nine not in and this one is. 03:15.880 --> 03:16.930 This one is. 03:16.930 --> 03:17.560 What was that? 03:17.560 --> 03:18.190 I forgot. 03:18.340 --> 03:20.020 Okay, not equal. 03:20.020 --> 03:25.120 So there's a lot of things available up here majority of the time that we use. 03:25.120 --> 03:30.580 Is this not in that if you want to check whether something some of the values is inside that area or 03:30.580 --> 03:31.030 not. 03:31.030 --> 03:33.880 But in this case, we are going to use only the phone here. 03:34.390 --> 03:38.890 In fact, some of the time I have seen majorly to being used greater than end the less than these are 03:38.890 --> 03:41.560 two, but we are going to be using greater than equal to also. 03:41.560 --> 03:46.780 So what happens in this case you can see in the greater then notice here they are saying DB don't inventory 03:46.780 --> 03:48.190 don't bother too much on that. 03:48.190 --> 03:53.920 Just remember we have this find method and inside this fine method we have the same parenthesis and 03:53.920 --> 03:55.930 inside that we have these curly braces. 03:55.930 --> 03:59.080 Inside this curly braces we are passing on a quantity. 03:59.080 --> 04:02.140 And then this quantity also goes into the curly braces. 04:02.140 --> 04:07.330 And then we go ahead and say, hey, dollar greater than all these operators actually need to pass on 04:07.330 --> 04:08.080 as dollar. 04:08.080 --> 04:13.150 So this dollar is really, really important and we go ahead and say, hey, this should be greater than 04:13.150 --> 04:17.530 20, so you need to search for something whose quantity is greater than 20. 04:17.530 --> 04:22.810 So this is really, really helpful and all the other things actually works almost exactly the same. 04:22.810 --> 04:25.120 You don't need to probably study them too much. 04:25.120 --> 04:26.950 You just need to just glance over them. 04:26.950 --> 04:31.570 So this one is going to be exactly same, but it's also going to match the equality as well. 04:31.570 --> 04:36.940 So if the quantity is 20, it's going to return that then we have less than and you guessed it right, 04:36.940 --> 04:40.510 it's it works exactly same and we have less than equal to as well. 04:40.510 --> 04:45.040 They work exactly same as you might be expecting them returning the value which is less than or equal 04:45.040 --> 04:46.720 to the 20 in this case. 04:47.170 --> 04:48.280 So this is all clear. 04:48.370 --> 04:48.930 Okay. 04:49.300 --> 04:52.120 Now moving on, coming back onto the code part. 04:52.840 --> 04:56.560 So we're going to go ahead and comment this out that we understand this much better part. 04:56.590 --> 04:58.810 Now, coming back on to the user controller. 04:58.810 --> 05:01.570 So this is the basic user controller that we have. 05:01.690 --> 05:02.920 We don't want to work on the user. 05:02.920 --> 05:03.480 We want to work. 05:03.630 --> 05:04.920 The model controller. 05:04.920 --> 05:09.240 So if I can find not model product controller, my bad. 05:09.330 --> 05:12.570 All I want to do here is I want to show that how it looks like. 05:12.570 --> 05:17.010 So I'm going to go ahead and simply say, hey, log me all the requests to dot query. 05:17.520 --> 05:22.880 So anything that's coming up into the query format, I just want to go ahead and see how it looks like. 05:22.890 --> 05:25.020 And this needs to go above. 05:25.050 --> 05:25.450 There you go. 05:25.470 --> 05:26.460 Now it's all happy. 05:26.790 --> 05:31.220 So anything that is going to come up into the question mark format is going to come in. 05:31.230 --> 05:36.210 So how this query actually looks like we are going to be reaching to the slash API, obviously slash 05:36.210 --> 05:38.690 V1, whatever is your path in this case. 05:38.700 --> 05:42.600 And then maybe you're searching for user or maybe you're searching for product. 05:42.900 --> 05:48.900 Now most of the application, when you are searching for maybe a shopping website, maybe a travel booking 05:48.900 --> 05:54.240 website, go AB or whatever you are searching for a hotel product, whatever you are searching for. 05:54.270 --> 05:59.070 The first thing is actually search and anything after the question mark is actually a query. 05:59.070 --> 06:00.430 So this is the by default. 06:00.450 --> 06:06.690 So what happens is inside the search, you pass on a kind of a a word that you are looking for, searching 06:06.690 --> 06:09.540 probably a simple string or something. 06:09.540 --> 06:11.460 So in our case, let's just say something. 06:11.460 --> 06:13.650 Someone is searching for a code related t shirt. 06:13.650 --> 06:16.590 So I'm going to say code or code or whatever you like to say this one. 06:16.650 --> 06:22.410 So now this can be a long string and change with the plus keyword and however you want to separate them. 06:22.410 --> 06:26.310 But in this case, we are going to be just choosing one word, just for an example. 06:27.000 --> 06:32.010 Now, not only that, there is one more keyword up here, so we use to separate these keywords and in 06:32.010 --> 06:34.560 person sign, this is how the query is being crafted. 06:34.620 --> 06:37.500 Now here you're going to see there is a keyword again, there is a page. 06:37.500 --> 06:40.040 So page can be equal to one or maybe two. 06:40.050 --> 06:43.400 So whatever you are doing, one or two, something like this. 06:43.410 --> 06:49.380 So sometimes you restrict the products that I don't want to show entirety of 200 or 2000 products on 06:49.380 --> 06:51.750 my website, I want to separate them on the page. 06:51.750 --> 06:53.340 So pagination goes in there. 06:53.340 --> 06:57.060 So you want to get a product on page number two, page number one or something like that. 06:57.060 --> 06:59.430 So this is also comes in as a query part. 06:59.520 --> 07:03.630 Now, not only that, sometimes you have, let's just say a category as well. 07:03.630 --> 07:06.480 So you go ahead and filter it out based on the category. 07:06.490 --> 07:11.430 So I'm going to go ahead and say, hey, category is equals to and then we go ahead and say this one 07:11.430 --> 07:13.740 is short sleeves. 07:13.740 --> 07:15.510 So this is the category as well. 07:15.540 --> 07:18.570 Further down the road, a user also wants to see that. 07:18.570 --> 07:26.100 I want to have only the t shirts whose rating is above four or maybe above three. 07:26.100 --> 07:31.320 So in that case, what we can do is we can go ahead and say, hey, rating and equals to four. 07:31.350 --> 07:35.800 Now how you actually craft this URL or this query is up to you. 07:35.820 --> 07:41.160 Now, usually a lot of people prefer to just get it as like rating equals to four and do all the manipulation 07:41.160 --> 07:42.870 on per root method. 07:42.870 --> 07:46.800 But you can actually go ahead and say something like this inside this bracket. 07:46.800 --> 07:49.560 You can say rating greater than or equal to four. 07:49.560 --> 07:52.470 So this is up to you what you pass on inside the rating. 07:52.470 --> 07:56.850 So at the time of in the front end itself, how you are crafting is heavily going to be depends. 07:56.850 --> 08:02.130 So this information needs to be 100% passed on to somebody who is playing in the front end. 08:02.160 --> 08:06.630 So again, in this case, let's just say we are going to go ahead and say that we accept parameters 08:06.630 --> 08:07.560 in this format. 08:07.560 --> 08:10.080 So user will be selecting just the four and three. 08:10.080 --> 08:13.650 But the way how this is going to be crafted in the front end is going to be like this. 08:13.650 --> 08:17.620 So inside the squared brackets, we just go ahead and grab get. 08:17.730 --> 08:22.800 There is a simple and very important role of why we are crafting that into a square bracket. 08:24.030 --> 08:26.670 Now, further down the road, this is not enough for me. 08:26.670 --> 08:28.860 I would like to have a little bit more of the query. 08:28.860 --> 08:34.080 So I'm going to go ahead and say, put another person and I'm going to say I want to restrict the pricing 08:34.080 --> 08:34.650 as well. 08:34.650 --> 08:42.150 So I'm going to go ahead and say, hey, pricing should be, let's just say, less than or equal to. 08:42.840 --> 08:50.100 I am looking for less than equal to maybe nine, nine, nine and I need to move that on to the just 08:50.100 --> 08:50.730 like that. 08:51.330 --> 08:54.510 And I can actually just for making sure you understand the things. 08:54.510 --> 08:55.650 I'll move this one here. 08:56.280 --> 09:00.740 And pricing is less than or equal to nine, nine, nine. 09:00.750 --> 09:03.480 And I also want to select the starter range as well. 09:03.510 --> 09:13.050 And price price is also going to be greater than or equal to 199. 09:13.050 --> 09:14.520 So you are looking for a range. 09:14.520 --> 09:20.370 So yes, this kind of complex query is very absolutely normal thing to deal with that this is the reason 09:20.370 --> 09:25.080 why we are actually working on the product in the email we have done with a different kind of complexity 09:25.080 --> 09:29.700 about the tokens and all these stuffs, but this is also another kind of complexity that works on and 09:29.700 --> 09:30.690 goes through with that. 09:30.720 --> 09:35.310 Now, as complex as your product is going to be, these queries may become a little bit longer as well. 09:35.310 --> 09:38.220 This is a very common phenomenon that happens quite a lot. 09:38.430 --> 09:39.000 Okay. 09:39.000 --> 09:42.660 So how we why this is important for us to discuss this part? 09:42.690 --> 09:43.800 It is very important. 09:43.800 --> 09:47.100 First, I want to walk you through with a little bit onto the other thing. 09:47.100 --> 09:54.960 So I'll take you on to a website which is an Mozilla developer network here, Mozilla developer, kind 09:54.960 --> 09:55.710 of a blog. 09:56.010 --> 09:56.210 Okay. 09:56.280 --> 09:58.770 So this is the page where the demo is the string replace. 09:58.770 --> 09:59.640 We have already seen that. 09:59.640 --> 10:03.330 How it works on it gives you to example there is a quick brown fox a. 10:03.380 --> 10:09.200 Example here it says console.log in this entire paragraph, just replace the dog with a monkey. 10:09.590 --> 10:10.220 We got that. 10:10.220 --> 10:11.480 We'll get the result here. 10:11.480 --> 10:18.290 And also, it gives you an example of regex or regular expression in which you replace the dog with 10:18.290 --> 10:19.160 the ferret. 10:19.490 --> 10:20.780 Let's see how it works on. 10:20.780 --> 10:22.350 So we see the two output here. 10:22.370 --> 10:25.520 The quick brown fox jumps over the lazy monkey. 10:25.610 --> 10:28.610 So notice here this time it says p dot replace. 10:28.610 --> 10:33.200 So the first time it says it sees the dog, it replaces it with the monkey. 10:33.620 --> 10:34.220 Acceptable. 10:34.250 --> 10:35.180 Totally doable. 10:35.420 --> 10:38.210 In the second case, the p dot replace. 10:38.210 --> 10:41.680 It says wherever you see the dog first time, just replace it with the ferret. 10:41.690 --> 10:44.330 So both of them are giving you the exact same result. 10:45.620 --> 10:47.750 We're not going to be using it this long example. 10:47.750 --> 10:53.030 We'll be actually crafting this example, something that we actually like to know and we like to work 10:53.030 --> 10:53.390 on. 10:53.390 --> 10:59.870 So we'll be having a GTI, GTI and LTY, so greater than equal to greater than equal to end LTE. 10:59.870 --> 11:05.210 But we just saw that they alone doesn't work like GTI and XLT and in the URL itself you cannot pass 11:05.210 --> 11:05.590 $1. 11:05.630 --> 11:11.180 It will automatically get converted into URL and coded just like space is converted into person 20. 11:11.420 --> 11:14.990 So the problem is the query that I'll be receiving up here. 11:14.990 --> 11:18.200 Notice here what we are sending here is having a GTI. 11:18.230 --> 11:20.240 Now I need to first worry about that. 11:20.240 --> 11:22.550 How can I make it as a dollar GTI? 11:22.550 --> 11:26.870 Because that is the query I can go ahead and pass on here in the email segment. 11:26.870 --> 11:29.330 Remember, let me just copy this line up here. 11:29.330 --> 11:34.010 So if I need to pass on something like this, this is important for me to convert that. 11:34.220 --> 11:37.220 So let me go back up here and inside this example. 11:37.220 --> 11:39.860 We are going to go ahead and paste this one. 11:39.860 --> 11:45.080 So now if I want to pass on this quantity, I have to pass on as dollar to 20. 11:45.080 --> 11:52.160 So the challenge one itself is to how to replace this price with something like price dollar GTI because 11:52.160 --> 11:53.990 dollar is not coming to me and shouldn't be. 11:53.990 --> 11:58.340 This is also a security risk, so let's go ahead and work out with that. 11:59.000 --> 12:01.940 So I'll go into this one and we have this GTI now. 12:01.940 --> 12:04.730 We have seen something like this replace already in the past. 12:04.730 --> 12:10.310 We have seen that we were looking for something like better and then this pace and we were saying that 12:10.310 --> 12:13.760 hey, whatever comes in, just go ahead and use like this. 12:13.760 --> 12:16.520 So what it does actually, it gives me just the empty token. 12:16.520 --> 12:17.390 We have already seen that. 12:17.390 --> 12:18.440 Very understandable. 12:18.710 --> 12:19.490 Nothing big deal. 12:19.490 --> 12:21.830 We are going to go ahead and remove this entirely. 12:21.980 --> 12:27.140 We're going to focus rather on the regex itself this time that how we can use the regex and do some 12:27.140 --> 12:27.650 stuff. 12:27.650 --> 12:31.940 So instead of the dog itself, I'm going to go ahead and say I want to look for GTI. 12:31.970 --> 12:37.070 Remember, two slashes are really important for these regex and then slash, I will see that what it 12:37.070 --> 12:40.220 actually works or not and how it actually works with that. 12:40.220 --> 12:41.330 Let's run this one. 12:42.350 --> 12:45.080 So it replaces whatever it finds it with the ferret. 12:45.080 --> 12:46.640 I don't want a ferret like this. 12:46.640 --> 12:50.540 I would rather like to convert that into a dollar GTI. 12:50.750 --> 12:56.150 The ultimate goal is not to just put a dollar on GTI, but actually on all of them GTI. 12:56.180 --> 12:57.170 Then again GTI. 12:57.170 --> 13:00.560 Then I want to put a dollar in front of all of them. 13:00.560 --> 13:06.080 So if I go ahead and do this right now, it, it places the dollar at one of the keyword, but not all 13:06.080 --> 13:06.650 of them. 13:06.770 --> 13:10.970 So I'm somewhere there, but it's not doing the job, all the places. 13:11.240 --> 13:13.790 Now, what if I just go ahead and add all of them? 13:13.790 --> 13:16.910 Let's just say I add LTE, also LTE. 13:17.000 --> 13:19.490 So obviously this is not a correct string. 13:19.490 --> 13:20.390 So what if I do? 13:20.390 --> 13:22.580 I put up a or statement in between them. 13:22.580 --> 13:23.810 Let's go ahead and run this. 13:24.080 --> 13:24.420 Okay. 13:24.440 --> 13:28.100 Now it's still it says, hey, I'm putting it up on the GTI, not on the LTE. 13:28.100 --> 13:30.320 So clearly this is not working. 13:30.320 --> 13:34.730 But let me break it to you already that no matter what you're going to do, you're going to use the 13:34.730 --> 13:35.630 OR character. 13:35.630 --> 13:41.240 So I'm going to go ahead and say, hey, GTI or you find LTE or whatever is the matching keyword you 13:41.240 --> 13:41.960 are looking for. 13:41.960 --> 13:46.310 But the problem with the regex is they are too quick to actually give you the output result. 13:46.550 --> 13:51.170 They actually go ahead and find whatever the first character is and they replace it with this guy. 13:51.620 --> 13:53.360 But there is another problem here. 13:53.360 --> 13:57.740 We have all of them, but this is not giving this is where the another magic of this comes in. 13:58.040 --> 14:01.880 Now, what you can do, this replace is a really complex one. 14:01.880 --> 14:06.710 So whatever the regex you are matching for, you can actually kind of throw a callback here. 14:06.710 --> 14:11.300 So whatever it matches, it actually gives you as a kind of a function back and you can just fire up 14:11.300 --> 14:16.280 a callback and into this whatever you can, you can actually return that or whatever. 14:16.280 --> 14:21.140 For example, if I just go ahead and say test, I go ahead and run that it says, Hey, test is not 14:21.140 --> 14:21.530 defined. 14:21.530 --> 14:24.770 So we actually can replace that with some kind of a string here. 14:24.890 --> 14:26.570 Let's go ahead and do that with it. 14:26.780 --> 14:31.700 Test a string and run that again and notice that the there it says test. 14:31.880 --> 14:34.160 Now, I don't want to replace it with the test. 14:34.160 --> 14:37.970 Obviously I want to replace it with the dollar GTI. 14:38.000 --> 14:41.250 Okay, let's go ahead and do that one by $1 GTI. 14:41.420 --> 14:42.260 Run that. 14:42.260 --> 14:43.850 Okay, this one is working fine. 14:43.850 --> 14:49.910 Now only thing I need to worry about is I need to figure out that how can I place dollar in front of 14:49.910 --> 14:50.480 all of them? 14:50.480 --> 14:52.310 How can I match all of these guys? 14:52.310 --> 14:58.070 Okay, so the first thing to do in all of that is I have to replace this I with G. 14:58.070 --> 14:59.570 G stands for Global. 14:59.570 --> 15:03.170 If I run this one now, it says, okay, you have a dollar GTI you. 15:03.230 --> 15:04.970 Every dollar and you have a dollar. 15:05.720 --> 15:07.400 So what happened this time? 15:07.400 --> 15:10.190 Whatever the first match is, it just replaces all of them. 15:10.190 --> 15:14.150 With these guys, we can actually go ahead and change this one. 15:14.150 --> 15:17.090 The reason why I'm writing em here, because this is a variable here. 15:17.090 --> 15:18.350 I can use a variable. 15:19.130 --> 15:24.290 So I'm going to go ahead and say, hey, remove this one and use a back tactics and the back text. 15:24.290 --> 15:30.350 I can say simply dollar and this, this is how we declare variable in them and we are going to go ahead 15:30.350 --> 15:35.990 and save match and I'm going to go ahead and say a match and after that I'm going to go ahead and write 15:35.990 --> 15:37.220 test just to show you. 15:37.490 --> 15:40.850 I notice here it says g t test, g t test and l t test. 15:40.850 --> 15:44.180 So whatever all it is matching in the global now this is being used. 15:44.180 --> 15:48.290 But this test is actually just to show you this is not how we are going to use that. 15:48.290 --> 15:52.970 What we want to do after the dollar is variable, but we want to add an additional dollar just like 15:52.970 --> 15:53.690 we added a test. 15:53.690 --> 15:56.660 After that, we're going to go ahead and use a dollar before it. 15:56.660 --> 15:58.160 I'm going to go ahead and run this. 15:58.190 --> 16:03.320 Okay, so now it looks like my problem is solved so I can have a dollar g t, dollar g, t t. 16:03.350 --> 16:06.560 So whatever the cases I want to batch, I can go ahead and use that. 16:06.560 --> 16:08.030 But there is a small problem. 16:08.030 --> 16:12.620 What if in the future something comes up as my g t. 16:13.160 --> 16:16.670 So if that comes in notice here it says my dollar. 16:17.660 --> 16:21.920 Okay, so this is just a kind of an odd case that we are facing up here. 16:21.920 --> 16:26.090 And in case you have worked any time in the past with these rejects, you know that these are really, 16:26.090 --> 16:27.470 really tricky one to handle. 16:27.470 --> 16:32.750 So in this case, what you can do is first, you can wrap whatever you want to match up here just like 16:32.750 --> 16:32.960 this. 16:32.960 --> 16:38.390 So wrap them in the parenthesis and then you can go ahead and simply define a boundary for the boundary. 16:38.390 --> 16:40.040 The slash B is being used. 16:40.040 --> 16:46.310 Now, if I run this one, it only matches either the values on the start or at the very end of it. 16:46.310 --> 16:49.160 And not not like end end of it. 16:49.160 --> 16:54.620 Like the string should start with only anything after that or previous that is not going to be converted. 16:54.620 --> 16:58.400 So we are strictly matching for just the values that you have given to me. 16:58.640 --> 17:03.080 Now it works in majority of the cases, but in the case of JavaScript, I have noticed that there is 17:03.080 --> 17:07.520 a slash B at the end of it is also required in some cases actually fails out. 17:07.520 --> 17:11.540 So the slashing are a trailing slash B again, this is same for boundaries. 17:11.540 --> 17:12.740 It is being required. 17:12.740 --> 17:18.260 So now whatever you pass on into this string, this is going to be converted as the matching string. 17:18.260 --> 17:21.380 So this is going to be very helpful for us in the future cases. 17:21.680 --> 17:22.110 Okay. 17:22.760 --> 17:28.130 So we have done a lot of detailed discussion about how regex works and how we can replace the values 17:28.130 --> 17:30.650 and how this actually gives you a method and all of that. 17:30.660 --> 17:34.970 In fact, if you're going to read all of this, this is all written up here that hey, actually this 17:34.970 --> 17:37.130 replace is a function replacement and all of that. 17:37.130 --> 17:38.660 So yeah, this is all written up here. 17:38.660 --> 17:41.330 It's not something I'm coming up magically out of the air. 17:41.870 --> 17:44.660 Okay, so this is all done coming back onto the code part. 17:44.690 --> 17:49.550 Now one problem is solved that I can go ahead and into this string. 17:49.550 --> 17:52.940 I can go ahead and inject dollar at every single piece of this. 17:53.150 --> 17:58.790 But in reality, this is really important to see up here. 17:59.000 --> 18:03.350 When I say quantity, for example, I'll say, okay, price or not price. 18:03.350 --> 18:06.260 Actually, in this case, yeah, we can actually use price. 18:06.260 --> 18:10.490 So I want to say price and price should be greater than 199. 18:10.490 --> 18:16.220 So how I'm going to craft this query in order to first craft that how this query actually works, I 18:16.220 --> 18:21.530 need to see that how it looks like and that's why I have added console.log request to query. 18:21.530 --> 18:25.640 So I'm going to go ahead and copy everything from slash product to everything. 18:25.640 --> 18:30.650 So I'm going to go ahead and save this one and I'm going to put a comment on this one as well. 18:31.490 --> 18:33.230 And let's go on up here. 18:33.650 --> 18:37.970 And when I was testing this test product, I actually added up a lot of code and stuff. 18:37.970 --> 18:41.090 So this is exactly what I tried before. 18:41.090 --> 18:42.530 Actually, I showed it to you. 18:42.530 --> 18:44.090 So this is what I was trying. 18:44.090 --> 18:45.110 Okay, moving on. 18:45.110 --> 18:49.220 So if I go ahead and paste this one again, I need to remove another slash. 18:49.220 --> 18:51.890 So this is the same query product question mark and all of that. 18:51.890 --> 18:55.520 And notice here in the params, they are also saying all these things that you are looking for. 18:55.520 --> 19:03.080 So gTLD ratings category and again remember this G20 always put on the fields which are actually numbers. 19:03.170 --> 19:06.290 Let's go ahead and send this and see what happens. 19:06.980 --> 19:10.790 I go ahead and send this and this says, hey, this is. 19:11.960 --> 19:12.920 Test product. 19:13.460 --> 19:15.020 Why cannot I get it? 19:16.190 --> 19:16.760 Okay. 19:17.760 --> 19:19.440 It looks like it is. 19:19.620 --> 19:20.250 Yeah. 19:21.090 --> 19:22.770 Are we not getting it at all? 19:23.400 --> 19:25.710 Request dot query it as product should be there. 19:26.040 --> 19:28.710 Let's go ahead and try it one more time and send it. 19:29.490 --> 19:31.290 And says, Hi, I cannot get it. 19:31.290 --> 19:34.710 Let's see that this is a slash test product slash product. 19:34.750 --> 19:35.030 Okay. 19:35.040 --> 19:36.510 I don't need to send the product here. 19:36.510 --> 19:38.900 Actually, I can just go ahead and say. 19:38.910 --> 19:39.630 Question mark. 19:39.630 --> 19:41.220 So this was wrong. 19:41.220 --> 19:42.300 Let's send it again. 19:42.300 --> 19:42.930 And there we go. 19:42.930 --> 19:44.280 Finally, we have received this. 19:44.340 --> 19:49.350 Now, the important thing which I want you want your attention on this one is this part. 19:49.590 --> 19:54.810 Notice here it actually crafts the entire query into this syntax. 19:55.020 --> 19:57.990 So notice here it says search. 19:58.440 --> 20:02.000 And the search is coming up as a standalone object in itself. 20:02.010 --> 20:04.350 The page is coming up as a standalone object. 20:04.350 --> 20:06.310 The important part is this rating. 20:06.330 --> 20:10.410 Now, notice here the slash end is also coming up because I actually copy pasted the stuff from the 20:10.410 --> 20:10.830 browser. 20:10.830 --> 20:17.220 Usually it doesn't happen, but notice here I can actually go ahead and copy this and go back into the 20:17.220 --> 20:18.240 code part. 20:19.520 --> 20:20.660 Into this one. 20:21.390 --> 20:26.520 And for a moment, let's just uncomment this one and try to compare what we have received. 20:26.520 --> 20:31.440 So we have received something like this, which is rating and we actually don't have the slash. 20:31.440 --> 20:34.280 And also this was just from copying and pasting. 20:34.290 --> 20:41.130 Now can you see how much similarity is there that if I want to use this a user find, I can actually 20:41.130 --> 20:46.890 go ahead and inside this parenthesis, I can just create a bracket up here and can pass on this query, 20:46.890 --> 20:49.980 which would be instead of looking the quantity, it would be saying rating. 20:49.980 --> 20:51.270 There we go, nice and easy. 20:51.270 --> 20:53.790 And after that, we already got this parenthesis. 20:53.790 --> 20:57.960 And inside the parenthesis we are getting a GTI and that is equal to four. 20:57.990 --> 21:03.060 Now obviously this four is right now a string because it is coming from the URL and all these stuffs, 21:03.060 --> 21:08.310 but it will be automatically be converted or we can actually convert it into a purely number format. 21:08.340 --> 21:15.780 Importantly here is that I have now the knowledge to convert this GTI into the dollar GTI and that's 21:15.780 --> 21:17.640 all it takes to find the query up here. 21:17.640 --> 21:22.170 And we will be using this exact same logic and syntax that I walked you through in this video. 21:22.170 --> 21:26.400 So it is really important for you to understand that what we are trying to do and how we are actually 21:26.400 --> 21:27.030 doing it. 21:27.030 --> 21:32.400 So we are going to go ahead and take all the query and when we take all the query itself, we are going 21:32.400 --> 21:33.090 to work like that. 21:33.090 --> 21:37.020 Now again, there is a little bit more to it, a little bit more to it, not just only this. 21:37.200 --> 21:41.520 Now notice here this entirety of the thing is coming up as an object. 21:41.520 --> 21:45.600 Now, our replacement method actually works only on string. 21:45.600 --> 21:47.400 That is a string specific matter. 21:47.580 --> 21:55.110 And in order to further put this data into the find query itself, then we have to convert it back into 21:55.110 --> 21:56.040 an object. 21:56.040 --> 22:00.420 So please remember this always that whatever the data comes up is going to be string. 22:00.420 --> 22:03.180 String first needs to be converted into JSON. 22:03.180 --> 22:08.820 So JSON we can use the methods of parse and string, ify and all of that and we can work through that. 22:09.120 --> 22:14.040 I know this is a really long video, but this kind of video is really important because that's whole 22:14.130 --> 22:17.460 what we are focusing on to the entirety of the operation. 22:17.460 --> 22:22.410 So remember the steps we have already studied that entirety of the pagination search filter. 22:22.410 --> 22:26.700 This is all what we are taking in just one single string and this is the real use case. 22:26.700 --> 22:29.340 This is how you will be actually coding this stuff. 22:29.340 --> 22:30.960 So I hope you have understood this one. 22:30.960 --> 22:32.190 I know really long. 22:32.190 --> 22:35.880 So a little bit boring as well, but this is really important topic. 22:35.910 --> 22:39.450 In the next video, we are going to go ahead and continue to write our product controller. 22:39.450 --> 22:44.220 I'm going to go ahead and comment this part as well so that it remains with you as an exercise. 22:44.220 --> 22:50.310 And not only that, I will also give you a little bit of this URL as well, so that later on you can 22:50.310 --> 22:51.420 practice this stuff. 22:51.420 --> 22:53.340 So let me go ahead and add this one. 22:53.340 --> 22:57.270 So this one is actually your URL, just like that. 22:57.270 --> 22:58.980 And let's go ahead and comment this. 22:59.280 --> 23:01.590 And also let me give you further down the road. 23:01.590 --> 23:06.180 This example also, maybe you want to have some more code with that. 23:06.180 --> 23:08.850 So this is all again, this is all a test file. 23:08.880 --> 23:12.990 I won't be like giving you or something more onto this one. 23:12.990 --> 23:13.620 This is it. 23:14.580 --> 23:14.900 Okay. 23:15.120 --> 23:16.050 Yes, that's all. 23:16.170 --> 23:16.950 All about it. 23:16.950 --> 23:21.240 Let's go ahead and move on to the next video and finally continue our journey into the product model. 23:21.240 --> 23:23.100 Let's go ahead and catch up in the next one.