/s3-and-aws-sdk-demo

[Advanced] - Using AWS-SDK to Create and List S3 Bucket

AWS-SDK and S3 Demo

[Advanced] - Using AWS-SDK to Create and List S3 Bucket

What is Amazon s3?

  • Stands for simple storage service
  • One of the first services in AWS
  • S3 is a safe place to store any type of files (text files, images, mp3)
  • You can think of s3 as Dropbox or GoogleDrive
  • Is Object based(Key & Value pair)
  • FIles are stored in buckets(similar to folder)
  • Bucket Names must be unique

What is aws-sdk?

  • Software Development Kit
  • A collection of tools for developers creating web applications provided by aws
  • Provides APIs, class libraries, and code samples
  • We will be using aws-sdk to communicate with s3

S3 and aws-sdk demo

  • We will create a bucket and list buckets in S3 by using AWS-SDK AWS Diagram
  1. After creating your serverless boilerplate/template run
npm init --yes
  • This will create a package.json file for you
  • package.json will allow us to install aws-sdk npm pakaage to use
  1. To install aws-sdk run
npm install aws-sdk
  • You should now see a node_modules directory in your current directory
  1. Require aws-sdk and create an s3 client in our handler.js file
  const AWS = require('aws-sdk');
  const s3 = new AWS.S3();

Create an s3 bucket and pass in data locally

Create Bucket - AWS SDK for JavaScript

s3.createBucket({ Bucket: "YOUR_BUCKET_NAME"}, function(err, data) {
   if (err) console.log(err, err.stack); // an error occurred
   else     console.log(data); // successful response
 });
  1. Hard code YOUR_BUCKET_NAME for now(We will add dynamically through Postman)
  2. Remove async keyword from lambda function
  3. Add callback parameter in lambda function
  4. Store return vaule in a variable named response
  5. Pass response into callback function callback(null, response)
  6. Run lambda function locally
  7. Pass in bucket name data dynamically
  8. Create a dummyData.json file. Add the following:
{
    "bucketName": "testingjay123"
}
  1. run with --path to pass in dummyData.json
serverless invoke local --path ./data.json

Post to a deployed lambda

  1. Before deploying lambda function, lets add a few code snippets to our serverless.yml file
  2. Add iamRoleStatements: to the end of provider::
  provider:
  name: aws
  runtime: nodejs8.10
  stage: dev
  region: us-west-2
  iamRoleStatements:
    - Effect: Allow
      Action:
        - s3:*
      Resource: "*"
  • This allows our deployed lambda function to access the s3 service
  1. Add integration: lambda under cors: true
functions:
  create:
    handler: handler.create
    events:
      - http: 
          path: create
          method: post
          cors: true
          integration: lambda
  • This allows us to recieve data passed in through Postman
  1. Deploy serverless
  2. Copy and paste the returned POST endpoint url and paste into Postman Post method
  3. In Postman, select Body -> raw -> select JSON(application/json) from the dropdown that says Text
  4. In the below input field, type in JSON data format exactly like the dummyData.json file

How to Create Multiple Lambda Functions

  1. Create new directory lambdas
  2. Rename handler.js to lambda name create.js
  3. Move existing lambda function create.js to 'lambdas' directory
  4. Change module.exports.create to module.exports.main in your create.js file
  5. Change handler below functions to create
  6. change value of handler property to lambdas/create.main
functions:
  create:
    handler: lambdas/create.main

Class Excercise

  • Make a GET request to get All Buckets data
  • Look through AWS SDK for JavaScript documentation to find the correct method

Resources

AWS.S3 — AWS SDK for JavaScript

AWS.S3 - AWS SDK - listObjects

What is Amazon S3?