CloudFormation custom resource catalogue

Collection of Cloud Formation custom resources written in node.js, result of months of continuous efforts to automate infrastructure management trough AWS CloudFormation. You may find some of these CloudFormation resources obsolete, as AWS team fills in the gaps. There is also some more complex ones, or developed to suite specific needs, such as reading JSON file from an S3 object, and making JSON values available through Fn::GetAtt intrinsic function. All of custom resources within this repository are meant to be deployed as AWS Lambdas for nodejs6.10 runtime

Collection of custom resources for Python can be found here

How to use

Simply clone the repository, install npm dependencies, and zip up the folder as lambda deployment package

git clone https://github.com/base2Services/cloudformation-custom-resources-nodejs.git && \
cd cloudformation-custom-resources-nodejs && \
npm install && \
zip -r ~/cfn-ccr-nodejs6.10.zip .

Dependencies

All dependencies are defined within package.json.

Custom resources

S3 Bucket cleanup

Removes all keys within a bucket. Role assumed by Lambda needs to have appropriate permissions to remove bucket keys, commonly set through Bucket policies.
Cleanup logic is implemented in 'DELETE' action. 'CREATE' and 'UPDATE' actions are just dummy stubs.

handler: cleanup-s3-bucket/index.handler

Required parameters:

• BucketName - String. Name of the bucket that should have it's keys cleaned up

ENI Cleanup

Detaches (if requiered) and deletes all ENIs within specified subnets. Cleanup logic is implemented in 'DELETE' action. 'CREATE' and 'UPDATE' actions are just dummy stubs.

handler: cleanup-subnet-enis/index.hanlder

Required parameters:

• SubnetIds - Array of Strings. Self explanitory - all subnets within this area shall have their ENI's cleaned up on stack deletion

Route 53 DNS Records creation

Creates, Updates and Cleans up Rotue53 DNS records in specified zone. All operations are done using assumed role that is passed down as Custom Resource parameters

handler: route53-changeset/index.handler

Required parameters:

• role - ARN of role that should be assumed by Custom Resource. It's assumed that user would just directly create Route53 records using supported resource types in same account where stack resides - so this is mandaroty parameter, as custom resource is intended to be used for managing records in account diferent from where stack is being created. This custom resource is making appropriate API calls for all 3 operations - CREATE, UPDATE and DELETE.

• recordset - json object with following properties

• • ttl - TTL for recrod set
• • zoneId - Route53 zone id where record should be created (PRs welcome to move from zoneId to ZoneName)
• • type - DNS Record type, e.g. A, CNAME ...
• • value - Actual value of DNS record

Reading values from JSON file on S3 bucket

Reads values from JSON file placed in S3 bucket, allowing this values to be referenced in other resources. Example of creating s3 bucket with name specified within JSON file can be found in src/read-s3-json-file/cf_template_example.json

handler: read-s3-json-file/index.handler

Required parameters:

• Bucket - name of bucket where configuration file resides
• Key - key within bucket of configuration file

Optional parameters:

• EnsureKeys - comma separated list of keys that are always returned out of custom resource. This ensures your Cloud formation does not break if property that does not exist in JSON file is passed around the stack. Key values will default to empty string, or value of EmptyKeyDefaultValue parameter

• EmptyKeyDefaultValue value for keys not present in JSON file and requested by EnsureKeys

Cognito UserPoolDomain

Creates UserPoolDomain for cognito user pool. This is currently not covered by CloudFormation.

runtime: nodejs6.10 handler: cognito-user-pool-domain/index.handler

Required parameters:

Please look at cognito-user-pool-domain/schema.json

Optional parameter GenerateRandomIfNotAvailable will try to append random string to requested domain name, if given name is not available. This process is repeated 5 times until handler reports an error.

Cognito UserPoolClient

Creates user pool client, as there is no cloudformation resource supporting all of the properties.

runtime: nodejs6.10 handler: cognito-user-pool-client/index.handler

Required parameters:

Please look at cognito-user-pool-client/schema.json