aws-lambda-url-shortener

Design / DB

Terms and Concepts

• A ShortURL represents a URL that has been shorten. They will be uniquely identified by a shortId.

Entity chart

Entity	PK	SK	GSI1PK	GSI1SK
ShortURL	SHORTURL#<shortId>	SHORTURL#<shortId>

Access patterns chart

Access pattern	Target	Parameters	Notes
ShortURL (CRUD)	Main table	shortId	Uniqueness requirement on shortId

Usage

Prerequistes

• dynampdb-local requires Java Runtime Engine (JRE) version 6.x or newer

• AWS account configured (default credential in ~/.aws or AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY set in terminal)

Get started

• clone the repo

• cd to/repo/path

• npm install

• npx serverless dynamodb install

• npm run start:offline

local dynamodb shell

dynamodb shell: http://localhost:8000/shell/

Test the API locally

curl -X POST "http://localhost:3001/dev/shorten" -d '{"url":"https://www.zermatt.ch/en/Webcams"}' | jq

curl -X GET "http://localhost:3001/dev/shorten/cKFT4QP"  | jq

curl -X GET "http://localhost:3001/dev/shorten"  | jq

open "http://localhost:3001/dev/cKFT4QP"

Pagination

The list operation returns up to 50 shortURLs and then the LastEvaluatedKey allows to run a new scan starting this last key.

Encoding the nested object for a querystring:

const querystring = require('querystring');

const LastEvaluatedKey = {
  SK: {
    S: 'SHORTURL#cKFT4QP',
  },
  PK: {
    S: 'SHORTURL#cKFT4QP',
  },
};

querystring.escape(JSON.stringify(LastEvaluatedKey));

// outputs
// '%7B%22SK%22%3A%7B%22S%22%3A%22SHORTURL%23cKFT4QP%22%7D%2C%22PK%22%3A%7B%22S%22%3A%22SHORTURL%23cKFT4QP%22%7D%7D'

Deploy

➜  aws-lambda-url-shortener git:(master) npx serverless deploy
Serverless: Packaging service...
Serverless: Excluding development dependencies...
Serverless: Creating Stack...
Serverless: Checking Stack create progress...
........
Serverless: Stack create finished...
Serverless: Uploading CloudFormation file to S3...
Serverless: Uploading artifacts...
Serverless: Uploading service URL-shortener.zip file to S3 (39.3 MB)...
Serverless: Validating template...
Serverless: Updating Stack...
Serverless: Checking Stack update progress...
......................................................................................................
Serverless: Stack update finished...
Service Information
service: URL-shortener
stage: dev
region: eu-west-1
stack: URL-shortener-dev
resources: 29
api keys:
  None
endpoints:
  POST - https://cxxxxxxxxb.execute-api.eu-west-1.amazonaws.com/dev/shorten
  GET - https://cxxxxxxxxb.execute-api.eu-west-1.amazonaws.com/dev/shorten/{shortId}
  GET - https://cxxxxxxxxb.execute-api.eu-west-1.amazonaws.com/dev/{shortId}
  GET - https://cxxxxxxxxb.execute-api.eu-west-1.amazonaws.com/dev/shorten
functions:
  createShortRL: URL-shortener-dev-createShortRL
  getShortURL: URL-shortener-dev-getShortURL
  redirectShortURL: URL-shortener-dev-redirectShortURL
  listShortURL: URL-shortener-dev-listShortURL
layers:
  None
Serverless: Deprecation warning: Starting with version 3.0.0, following property will be replaced:
              "provider.iamRoleStatements" -> "provider.iam.role.statements"
            More Info: https://www.serverless.com/framework/docs/deprecations/#PROVIDER_IAM_SETTINGS

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Serverless: Announcing Metrics, CI/CD, Secrets and more built into Serverless Framework. Run "serverless login" to activate for free..
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Contributing

Anyone and everyone is welcome to contribute.

Issues

Find a bug or want to request a new feature? Please let me know by submitting an issue.

Licensing

Licensed under the MIT License

A copy of the license is available in the repository's LICENSE file.