aws-existence v0.1.1

aws-existence

Methods which simplify checking whether or not AWS resources exist.

Usage

var ex = require('aws-existence')
var ec2 = ex.ec2({region: 'us-west-2'})

ec2.doesSecurityGroupExist('mySecurityGroup')
  .then(doSomething)
  
function doSomething(exists) {
  if (exists) {
    // DESTROY IT!!!
  } else {
    // MAKE IT!!!
  }
}

There are several other methods which also work like this. I'm sorry but for now you just have to look at the source to see which ones are available. Hundreds still need to be developed, and I'd appreciate any and all help.

Checking if a resource exists with the SDK is absurdly difficult!

It should be this easy:

• You should ask doesMyResourceExist.
• Pass something which identifies that type of resource uniquely.
• Receive a Promise which is resolved to true if the resource exists, and false if it doesn't.

That's it!

Working Around the Problem

There are only a few aws-sdk clients which provide methods for checking existence. I know s3.doesBucketExist is a thing, but I can't remember any others off the top of my head. This module is built from the opinion that this is an oversight, there should always have been existence checking methods in the sdk.

There are a few ways to work around the problem, but unfortunately the sdk clients differ enough, to be more annoying than useful. But that's why this module exists to hide that annoyance.

existence inconsistencies

• Multiple method conventions: get*, describe*, and list* methods.
• Plural vs Singular: describeInstances, describeTable, getRole
• Responses: Objects, Collections

non-existence inconsistencies

• Generic Exceptions ResourceNotFoundException
• Specific Exceptions NoSuchEntity, LoadBalancerNotFound, or InvalidGroup.NotFound.
• Null response
• Empty collection: [ ]

It's all further complicated because each client takes specific and varying params as well.

Disclaimer

This is a Work In Progress, no promise is made about completeness. Please contribute new methods!

Install

npm install --save aws-existence