1 00:00:00,240 --> 00:00:01,170 In this video. 2 00:00:01,200 --> 00:00:06,600 Finally, we are going to start developing our product microservices lambda function. 3 00:00:06,600 --> 00:00:12,210 So this will be using a SDK for JavaScript version three libraries. 4 00:00:12,210 --> 00:00:18,900 We are going to install NPM package, which is the client dynamic DB and required package from the dynamic 5 00:00:18,900 --> 00:00:22,530 DB interactions for the SDK JavaScript version three. 6 00:00:23,010 --> 00:00:28,470 So we will develop our lambda function as a Node.js project in our local computers with using visual 7 00:00:28,550 --> 00:00:29,280 pseudocode. 8 00:00:29,310 --> 00:00:35,310 After that, we will zip and upload our Node.js project into lambda function on the cloud environment. 9 00:00:35,310 --> 00:00:36,960 So let's get started. 10 00:00:36,990 --> 00:00:39,600 Please open the widgets to the code. 11 00:00:39,600 --> 00:00:45,810 I have created a separate folder in the lecture, but from now on we will continue through the the same 12 00:00:45,810 --> 00:00:48,030 folder until this section is finished. 13 00:00:48,030 --> 00:00:53,760 So that means I will be develop this project into this folder as a Node.js application. 14 00:00:53,760 --> 00:01:01,770 So, so these lambda function will be develop into the our folder of the lecture 189 which name is product 15 00:01:01,770 --> 00:01:03,030 cloud microservices? 16 00:01:03,330 --> 00:01:04,560 Okay, let's get started. 17 00:01:04,560 --> 00:01:08,070 I'm going to start with creating index JS file. 18 00:01:08,100 --> 00:01:15,690 This will be our actual lambda function, but before that we should create a package JSON file. 19 00:01:15,720 --> 00:01:22,500 In order to do that, please open the terminal and go to locate the folder structure. 20 00:01:23,440 --> 00:01:32,340 Of the correct one, which is the Section 21 and Lecture 189 product microservices OC. 21 00:01:32,410 --> 00:01:42,760 In this folder structure in the PowerShell command window, I'm going to run NPM init by command in 22 00:01:42,760 --> 00:01:46,540 order to create package JSON file with default values. 23 00:01:46,540 --> 00:01:53,230 So please hit the enter and this will be generate a package JSON file for this folder and this folder 24 00:01:53,230 --> 00:01:56,980 will be our product microservice lambda function. 25 00:01:56,980 --> 00:02:01,630 So if you open the package JSON file, you can see the default values of our application. 26 00:02:01,720 --> 00:02:08,440 So basically the first thing we should do that we should add a type and type should be modeled. 27 00:02:08,830 --> 00:02:14,530 So this is very important as you know, that we should add type model in order to gain ActionScript 28 00:02:14,560 --> 00:02:19,150 six standards and modular architecture on the SDK JavaScript Version three. 29 00:02:19,270 --> 00:02:23,740 These provide to use most eclipse codes into our Node.js projects. 30 00:02:23,740 --> 00:02:26,260 For example, we can add the import statements. 31 00:02:26,260 --> 00:02:27,760 So that's why this is mandatory. 32 00:02:27,760 --> 00:02:29,950 Please don't forget to add this line of code. 33 00:02:30,220 --> 00:02:33,190 Okay, let's continue the install required package. 34 00:02:33,490 --> 00:02:36,100 We edit the empty package json file. 35 00:02:36,100 --> 00:02:38,380 That means there is no any package now. 36 00:02:38,380 --> 00:02:42,670 So now we can start to installing required npm packages. 37 00:02:42,670 --> 00:02:45,550 So which packages are we are required. 38 00:02:45,550 --> 00:02:52,810 So if you look at our architecture in product microservices, it is required to dynamo ADB HDC packets. 39 00:02:52,810 --> 00:03:00,430 So that's why we should NPM install to record the ADB package which including a K JavaScript version 40 00:03:00,430 --> 00:03:01,270 three version. 41 00:03:01,390 --> 00:03:03,700 So how we can get these packets. 42 00:03:03,700 --> 00:03:09,670 So if you look at our documentation here, you can see the API reference documentation for HDC. 43 00:03:09,670 --> 00:03:16,000 So you can see that there is lots of packets that can available for our SDK libraries. 44 00:03:16,000 --> 00:03:20,530 So I'm going to search for the client dash Dynamo DB. 45 00:03:23,330 --> 00:03:31,580 So if you search for the client based on IMDB, you should search for the right hand side and open this 46 00:03:31,580 --> 00:03:32,480 dynamic TV. 47 00:03:32,510 --> 00:03:38,240 So that means we will use these packages when interacting or line IMDB to perform perturbation. 48 00:03:38,270 --> 00:03:44,180 If you scroll down, you can see the NPM install command so we can see the package detail into API reference 49 00:03:44,180 --> 00:03:47,540 documentation of SDK version three. 50 00:03:47,630 --> 00:03:52,670 So go to Dynamo DB package and find the installing part and copy this line of code. 51 00:03:52,850 --> 00:04:00,380 So we are using these NPM packages and this is the our first requirement for the NPM dependencies. 52 00:04:00,380 --> 00:04:05,750 I'm going to copy this line of code and come to our package JSON file. 53 00:04:06,080 --> 00:04:13,550 So in the same location, I'm going to copy and paste, which is the NPM install client dynamo DB. 54 00:04:13,580 --> 00:04:16,850 So hit the enter and see what's going happened. 55 00:04:17,690 --> 00:04:24,860 So as you can see that this is creating required node modules folder and will be modify or package JSON 56 00:04:24,860 --> 00:04:25,430 file. 57 00:04:26,610 --> 00:04:27,360 Yes. 58 00:04:27,360 --> 00:04:30,390 See that nobodies are created successfully. 59 00:04:30,390 --> 00:04:35,820 And if you check the our package JSON file, if you scroll down you can see the dependencies of the 60 00:04:35,820 --> 00:04:37,680 dynamic DB edit successfully. 61 00:04:37,680 --> 00:04:42,120 So that means we are ready to use these packages into our index. 62 00:04:42,120 --> 00:04:44,730 JS which will be the lambda function code. 63 00:04:45,430 --> 00:04:48,760 So also we need to install one more package. 64 00:04:48,850 --> 00:04:53,890 Install required dynamic ADB SDK package, which is the util dynamic db. 65 00:04:54,280 --> 00:04:57,070 I'm going to show the details in the documentation. 66 00:04:57,190 --> 00:05:01,660 You can come here and see that there is a util library for dynamic DB. 67 00:05:01,690 --> 00:05:06,950 This package provides utilities to be used in the client dynamic DB package. 68 00:05:06,970 --> 00:05:14,170 And if we look at the dynamic DB document class, it is automatically performs the necessary marshalling 69 00:05:14,170 --> 00:05:15,900 and marshalling operations. 70 00:05:15,910 --> 00:05:20,470 So see that there is two main method which is the Marshall and Marshall. 71 00:05:20,500 --> 00:05:26,830 And you can see that these utility class are important to Marshall and Marshall operation. 72 00:05:26,860 --> 00:05:29,740 You can see the example on this documentation here. 73 00:05:29,740 --> 00:05:33,140 You can see that there is an item definition of the dynamic DB. 74 00:05:33,160 --> 00:05:39,340 So with the Marshall method, we don't specify any data type of the dynamic DB Normally, maybe you 75 00:05:39,340 --> 00:05:46,390 remember in the last section, we always provide the data types like string as or number. 76 00:05:46,390 --> 00:05:50,880 And so Marshall Method avoid these kind of operations. 77 00:05:50,890 --> 00:05:56,260 We only write the item, value, item, value and item name in here. 78 00:05:56,290 --> 00:06:02,560 This is providing some utilities and providing unnecessary data types using from the Dynamo DB. 79 00:06:02,560 --> 00:06:07,180 It is automatically perform these data type operations on behind the scenes. 80 00:06:07,180 --> 00:06:12,430 So that's why it is very useful utilization package that we are going to use here. 81 00:06:12,430 --> 00:06:16,060 You can see, for example, get item from the Dynamo DB. 82 00:06:16,090 --> 00:06:24,220 Normally when we are get item operation in the key section, we provide the number and string parameter 83 00:06:24,250 --> 00:06:24,850 in here. 84 00:06:24,850 --> 00:06:29,640 But with Marshall, we only provide a partition key and passing key value. 85 00:06:29,880 --> 00:06:36,910 Okay, we understand the utility library and now it is time to install the required utility package 86 00:06:36,910 --> 00:06:38,050 to our application. 87 00:06:38,050 --> 00:06:41,000 Please go back to package json file in here. 88 00:06:41,020 --> 00:06:45,160 So another so another NPM package is in here. 89 00:06:45,190 --> 00:06:46,810 You can see that we will. 90 00:06:46,810 --> 00:06:47,230 Right. 91 00:06:47,230 --> 00:06:50,830 NPM install a double SDK utility db. 92 00:06:50,860 --> 00:06:54,070 So I hit the enter to install this package. 93 00:06:54,770 --> 00:06:56,150 And wait for a while. 94 00:06:57,200 --> 00:06:59,300 As you can see that in the dependencies. 95 00:06:59,300 --> 00:07:04,510 Now we have two dependencies to interact with Dynamo DB and perform business logics. 96 00:07:04,520 --> 00:07:09,680 So finally we are ready to start the development with using these ac-dc packets.