aws-liveness

AWS Liveness tools.

Install

npm i --save aws-liveness

Usage

const AWSLiveness = require('aws-liveness');
const { DynamoDB } = require('aws-sdk');
 
const awsLiveness = new AWSLiveness();
const dynamoDBClient = new DynamoDB();
 
// ping and wait services up to 10 seconds
awsLiveness.waitForServices({
  clients: [dynamoDBClient],
  waitSeconds: 10
})
  .then(() => console.log('services liveness ok'))
  .catch(console.error);
 
// ping a service
awsLiveness.ping({ client: dynamoDBClient })
  .then(() => console.log('dynamodb ping success'))
  .catch(console.error);

Customization

You can customize and/or extend aws-liveness tools to fit your application needs.

const AWSLiveness = require('aws-liveness');
const { DynamoDB } = require('aws-sdk');
 
class MyCustomService {
  async fetchSomeData () {
    return { foo: 'bar' }
  }
}
 
const customServices = [{
  test: client => client instanceof DynamoDB,
  ping: client => client.describeTable({ TableName: 'Foo' }).promise()
}, {
  test: client => client instanceof MyCustomService,
  ping: client => client.fetchSomeData()
}]
 
const awsLiveness = new AWSLiveness({ services: customServices });
const dynamoDBClient = new DynamoDB();
const myCustomService = new MyCustomService();
 
awsLiveness.ping({ client: dynamoDBClient })
  .then(() => console.log('dynamodb ping success'))
  .catch(console.error);
 
awsLiveness.ping({ client: myCustomService })
  .then(() => console.log('my custom service ping success'))
  .catch(console.error);

Debug

AWS Liveness uses debug module internally to log information about ping requests and services status. Logging is turned off by default and can be conditionally turned on by setting the DEBUG environment variable equals to aws-liveness.

Examples

Localstack

You can use this module to ensure that LocalStack services are up and running before you test and/or start your application.

// ping-localstack.js
const dynamoDBClient = new DynamoDB({
  endpoint: process.env.DYNAMODB_ENDPOINT
});
 
if (require.main === module) {
  awsLiveness.waitForServices({
    clients: [dynamoDBClient],
    waitSeconds: process.env.WAIT_SECONDS || 10
  })
    .catch(console.error);
}

{
  "scripts": {
    "localstack": "docker run -it -p 4569:4569 -p 9999:8080 --rm localstack/localstack",
    "localstack-wait": "AWS_ACCESS_KEY_ID=fakeid AWS_SECRET_ACCESS_KEY=fakekey node ping-localstack.js",
    "start": "node app.js",
    "test-e2e": "AWS_ACCESS_KEY_ID=fakeid AWS_SECRET_ACCESS_KEY=fakekey mocha test-e2e/**/*.test.js",
  }
}

DYNAMODB_ENDPOINT=http://localhost:4569 npm run localstack-wait && npm run test-e2e

Contributing

1. Commits to master must be done through a Pull Request and Squash and Merge option.

2. Add a title and body that follows the Conventional Commits Specification.