Serverless Plugin AWS Resolvers

Resolves variables from ESS, RDS, or Kinesis for serverless services

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A plugin for the serverless framework that resolves deployed AWS services to variables from ESS, RDS, EC2, dynamodb or Kinesis.


  # See
  ess: ${aws:ess:my_cluster_name:Endpoint}
  # See
  rds: ${aws:rds:my_db_name:InstanceCreateTime}
  # See
  rdsaurora: ${aws:rdsaurora:my_cluster_name:Endpoint}
  kinesis: ${aws:kinesis:my_kinesis_stream:StreamARN}
  dynamodb: ${aws:dynamodb:my_dynamodb_table:LatestStreamArn}
  securityGroup: ${aws:ec2:securityGroup:my_vpc_name-my_group_name:GroupId}
  subnet: ${aws:ec2:subnet:my_subnet_name:SubnetId}
  vpc: ${aws:ec2:vpc:my_vpc_name:VpcId}
  ecs: ${aws:ecs:cache_cluster_name:CacheClusterId}
  cf: ${aws:cf:stack_name`_`logical_resource_id:PhysicalResourceId}
  apigateway: ${aws:apigateway:my_api_name:id}
  apigatewayv2: ${aws:apigatewayv2:my_api_name:ApiId}

Given a service, a key, and a property, this plugin will resolve the variable directly from AWS. This uses the IAM role of the executor of the serverless binary.

This plugin also exposes a command to resolve a variable sls resolveAwsKey --k aws:ess:my_cluster_name:Endpoint

See our webpage for full documentation.

Array access

To access values in arrays (for example the ElastiCache Endpoint in CacheNodes), the variableSyntax of serverless needs to be amended.

  variableSyntax: "\\${([ ~:a-zA-Z0-9._\\'\",\\-\\/\\(\\)\\[\\]]+?)}"

    ECS_ADDRESS: ${aws:ecs:ecs-instance:CacheNodes[0].Endpoint.Address}


This plugin has one available configuration option at the moment.

    strict: true

Disabling strict mode allows values of non-existing infrastructure to be overwritten by other values. This is especially useful when the serverless configuration also contains the CloudFormation template to create this infrastructure. On the first run the value would not be available and would prevent the template from being applied.

Values can be overwritten like this:

    strict: false
  rds: ${aws:rds:my_db_name:InstanceCreateTime, 'not created yet'}

Version History

  • 2.1.0
    • Broad dependency update
    • Add Aurora clusters (thanks @kschusternetformic)
  • 2.0.2
    • Dependency security update
    • Fix deprecation warning (Thanks @dnicolson)
  • 2.0.1
    • Correctly depend on node >= 12
  • 2.0.0
    • Large dependency upgrade, remove babel runtime dependency.
  • 1.4.0
    • Add ability to get CF Physical Resource ID (thanks @supaggregator)
  • 1.3.3
    • Update versions for dependabot secruity vulnerabilities
  • 1.3.2
    • Fix security issue with lodash (thanks @rmbl)
  • 1.3.1
    • Add support for elasticache resources (thanks @rmbl)
  • 1.3.0
    • Add a strict mode flag and don't error on non-existing infrastructure when strict mode is not on (thanks @rmbl)
  • 1.2.1
    • Allow object access for the variable name (thanks @rmbl)
  • 1.2.0
    • Add support for DynamoDB stream ARN (thanks @geronimo-iia)
  • 1.1.0
    • Add support for EC2 resources (thanks @kevgliss)
  • 1.0.0
    • Initial release