1 00:00:00,240 --> 00:00:06,420 In this video, we are going to develop the function for asynchronous invocation from Amazon S3. 2 00:00:06,690 --> 00:00:08,010 Let's get started. 3 00:00:08,040 --> 00:00:09,780 Please open to decode. 4 00:00:09,780 --> 00:00:12,900 And I have created separate section and lecture folder. 5 00:00:12,990 --> 00:00:18,390 And from now on, we will develop this lecture folder and this will be the our Node.js application. 6 00:00:18,570 --> 00:00:23,970 So in this video, we will develop our lambda function and we have to interaction. 7 00:00:23,970 --> 00:00:27,360 First of all, get bucket detail from Amazon S3. 8 00:00:27,390 --> 00:00:33,310 And after that, we will write Dynamo DB Table with details of the S3 bucket and object theme. 9 00:00:33,330 --> 00:00:37,110 So these are the two interactions to develop our lambda function. 10 00:00:37,110 --> 00:00:39,210 I have created indexes in here. 11 00:00:39,210 --> 00:00:44,910 So in the index case you can see the basic 100 method, which is the lambda function hundred method 12 00:00:44,910 --> 00:00:48,980 and this is the boilerplate code that we can develop together. 13 00:00:48,990 --> 00:00:54,330 So as you can see that in the first line of code we have locked the incoming event and after that we 14 00:00:54,330 --> 00:00:56,790 return back to 200 success response. 15 00:00:56,790 --> 00:01:02,410 So in the to do part, we will perform our actual logic, which is the get information about the bucket 16 00:01:02,410 --> 00:01:05,790 details and write these details into Dynamo DB table. 17 00:01:06,210 --> 00:01:09,120 For that purpose, let me write with the zero code. 18 00:01:09,120 --> 00:01:15,540 So that means we will first of all, with the incoming event, we will list the objects into the bucket. 19 00:01:15,540 --> 00:01:22,080 So that means it is required the S3 integration from the Lambda function to get objects from the bucket 20 00:01:22,080 --> 00:01:24,840 because in the event we have bucket information. 21 00:01:24,840 --> 00:01:31,170 So after that we will write these object details on Dynamo DB table. 22 00:01:31,170 --> 00:01:36,960 So these are the two steps that we are going to develop in this lambda function and we will start with 23 00:01:36,960 --> 00:01:38,940 the listing object into bucket. 24 00:01:39,210 --> 00:01:44,160 So for list object into bucket, we will use a HDC JavaScript library. 25 00:01:44,160 --> 00:01:51,360 So if you open the our S3 client object, we will use the list object command. 26 00:01:51,360 --> 00:01:57,510 If you search for the list object command, I'm going to use version two command because version two 27 00:01:57,510 --> 00:01:58,560 is the latest one. 28 00:01:58,560 --> 00:02:04,350 If you open the list object, version two command, you can see all the details in here that we will 29 00:02:04,350 --> 00:02:07,410 use for listing objects into given bucket name. 30 00:02:07,410 --> 00:02:11,820 So basically it is returning all objects in the bucket with each request. 31 00:02:11,850 --> 00:02:17,520 We can use the request parameters as the selection criteria and we can use these operations. 32 00:02:17,520 --> 00:02:20,010 We must have the read access. 33 00:02:20,010 --> 00:02:22,860 You can read these very important word. 34 00:02:23,010 --> 00:02:27,990 In order to use this operation, we have to have read access to the bucket. 35 00:02:28,020 --> 00:02:34,320 This is very important, which is the also performing and perform to list bucket action. 36 00:02:34,320 --> 00:02:40,350 To do that, we should give this list bucket item policy into our permissions of the lambda function. 37 00:02:40,590 --> 00:02:48,570 If you don't give this permission when we run these invoke lambda function, this will be throw an exception 38 00:02:48,570 --> 00:02:55,140 about the action required permissions access not exception and access tonight about the list bucket 39 00:02:55,140 --> 00:02:55,980 operations. 40 00:02:55,980 --> 00:02:59,760 We should give this permission into our lambda function for that purpose. 41 00:02:59,760 --> 00:03:04,590 Please go to lambda function, go to S3 function configuration permission. 42 00:03:04,590 --> 00:03:10,410 If you scroll down and if you select the resource summary dropdown box and select the Amazon S3, you 43 00:03:10,410 --> 00:03:14,100 can see that we have only get object action. 44 00:03:14,100 --> 00:03:21,780 But for our business case we will listing S3 objects and we also need to list object action that is 45 00:03:21,780 --> 00:03:23,760 explained in the documentation. 46 00:03:24,120 --> 00:03:30,030 So for that purpose, I'm going to at least bucket requirement permission into our role. 47 00:03:30,030 --> 00:03:36,300 And in order to do that, I'm going to right click and open new tab for the role name and this will 48 00:03:36,300 --> 00:03:43,350 be open the IAM role and in the I am role page, I'm going to go to permission policies. 49 00:03:43,350 --> 00:03:47,850 You can see the permissions and this is my role name of our lambda function. 50 00:03:47,850 --> 00:03:53,370 If you scroll down you can see the permission policies and we have three policy, one for the Lambda 51 00:03:53,370 --> 00:03:58,200 Basic execution role, which is the default one and one for the Lambda Microservice execution role, 52 00:03:58,200 --> 00:04:03,360 which is the dynamic DB cloud operations and one for the Lambda S3 execution role. 53 00:04:03,390 --> 00:04:09,360 It is only including get object, but we also need to list bucket list bucket permissions. 54 00:04:09,360 --> 00:04:09,620 Okay. 55 00:04:09,690 --> 00:04:11,490 Now we can add the required permission. 56 00:04:11,490 --> 00:04:14,040 You can see in here there's a permission button. 57 00:04:14,040 --> 00:04:17,100 If you click this button, you can see the attached policies. 58 00:04:17,100 --> 00:04:18,840 I'm going to attach policy. 59 00:04:18,840 --> 00:04:21,990 So in here I'm going to search for the S3. 60 00:04:21,990 --> 00:04:27,660 You can search for the S3 and here you can see the Amazon S3 return access. 61 00:04:27,660 --> 00:04:33,660 If you expand this policy, you can see that it is called the list, object, list, bucket and so on. 62 00:04:33,660 --> 00:04:37,920 All these actions is handled in the Amazon S3 Return Access. 63 00:04:37,920 --> 00:04:43,680 So please select these Amazon S3 Return Access and click the attach policy. 64 00:04:44,740 --> 00:04:47,690 So it is successfully attached to my role. 65 00:04:47,710 --> 00:04:54,640 If you scroll down, verify that Amazon S3 don't access attached and these including the list object 66 00:04:54,640 --> 00:04:57,370 and list bucket permissions in our world. 67 00:04:57,500 --> 00:04:58,720 Okay, very good. 68 00:04:58,720 --> 00:05:06,310 So now we can go back to our lambda function if you refresh the page and come here as three functions 69 00:05:06,310 --> 00:05:08,830 and go to configuration and permission. 70 00:05:08,830 --> 00:05:15,580 This time, if you select the Amazon three, you can see that we have also get and list object resources 71 00:05:15,580 --> 00:05:16,690 added successfully. 72 00:05:16,690 --> 00:05:22,240 Okay, now we can focus on the code part, but before that let's review the documentation. 73 00:05:22,240 --> 00:05:27,880 If you go back to the documentation, we are going to use list object version two command for listing 74 00:05:27,880 --> 00:05:30,910 object into bucket and we give required permission. 75 00:05:30,910 --> 00:05:33,610 If you scroll down, we will see the example usage. 76 00:05:33,610 --> 00:05:39,960 Here you can see the command and this is the our client is three package and we will use is modules 77 00:05:40,000 --> 00:05:44,290 to import statement and the rest of the code is very same. 78 00:05:44,290 --> 00:05:50,830 We are creating a client object and sent client object to this command to perform our business logic 79 00:05:50,950 --> 00:05:52,690 and passing the parameters. 80 00:05:52,690 --> 00:05:56,980 These are the very same and you can check the input parameter in here. 81 00:05:56,980 --> 00:06:01,300 Basically, we will give this kind of properties when requesting list object. 82 00:06:01,300 --> 00:06:03,790 The important parameter of course, the bucket name. 83 00:06:04,030 --> 00:06:06,670 Okay, let's start to developing our application. 84 00:06:06,670 --> 00:06:12,790 If you open the Visual Studio code, you can think that this will be the our Node.js application for 85 00:06:12,790 --> 00:06:13,600 that purpose. 86 00:06:13,630 --> 00:06:21,520 In this folder structure, I'm going to create a package JSON file with running the NPM init via command. 87 00:06:21,550 --> 00:06:28,540 Please open a terminal and go to record section and go to record lecture. 88 00:06:28,540 --> 00:06:36,220 File lecture will be 250 and now I'm going to run npm init dash. 89 00:06:36,220 --> 00:06:40,720 Why this will be create a package JSON file with the default information. 90 00:06:40,720 --> 00:06:46,900 You can see in here we have created a package JSON file and the first thing we should do that the adding 91 00:06:46,930 --> 00:06:54,520 type module in here, come here and click the type and set the module in order to activate script six 92 00:06:54,520 --> 00:06:58,600 modules and Script six standards, we should add type module. 93 00:06:58,600 --> 00:07:01,720 Please don't forget this and save this package JSON file. 94 00:07:01,840 --> 00:07:04,320 Now we can install required packages. 95 00:07:04,330 --> 00:07:09,190 If you come back to our list object, you can come to S3 client. 96 00:07:09,220 --> 00:07:17,200 See that we are going to use client S3 package for the SDK JavaScript version three copy this NPM, 97 00:07:17,200 --> 00:07:23,860 install command and go back to our visual code and please make sure that you are in the correct folder 98 00:07:23,860 --> 00:07:26,170 structure and paste this command in here. 99 00:07:26,170 --> 00:07:32,230 This will be install the required S3 package into our package JSON file and these are Node.js application 100 00:07:32,230 --> 00:07:34,510 that we are going to deploy our lambda function. 101 00:07:35,250 --> 00:07:42,900 So after finishing this install operation, we will see the package JSON file and check the dependencies. 102 00:07:44,360 --> 00:07:44,830 Okay. 103 00:07:44,840 --> 00:07:50,690 If you scroll down in the package JSON file, you can see that we have successfully instal required 104 00:07:50,840 --> 00:07:54,230 a client package from the our SDK. 105 00:07:54,260 --> 00:08:00,990 Now it is time to create S3 client separate Node.js module to perform our actions. 106 00:08:01,010 --> 00:08:06,140 Please create S3 Client JavaScript file into our directory. 107 00:08:06,620 --> 00:08:17,240 Come here and create a neve S3 client that JavaScript file and I'm going to develop this file with this 108 00:08:17,240 --> 00:08:18,140 line of codes. 109 00:08:18,170 --> 00:08:23,780 As you remember that we are using S3 client from these HDC packets and we are in the region, US is 110 00:08:24,320 --> 00:08:29,920 and basically we are creating a new client and export this client into the separate Node.js model. 111 00:08:29,930 --> 00:08:35,540 So this helps to decrease the package size and increase the call start issues. 112 00:08:35,660 --> 00:08:38,930 Okay, now we can focus on developing our function. 113 00:08:39,170 --> 00:08:43,540 As you remember that we have two items that we will interacting. 114 00:08:43,700 --> 00:08:48,360 S3 Bucket for listing object into bucket and we will write on the DB table. 115 00:08:48,380 --> 00:08:53,690 We have installed the required bucket client object and now we can develop this part. 116 00:08:53,690 --> 00:08:56,990 In the next video we will implement list object into bucket.