Common utility for configuring AWS services in a DBOS Transact application.

By default, services just use a configuration called 'aws_config'.

Start by giving a name to a configuration for an AWS service or role. In dbos-config.yaml, under 'application', make a section with all the AWS bits:

 aws_config:
  aws_region: us-east-2
  aws_access_key_id: ${AWS_ACCESS_KEY_ID}
  aws_secret_access_key: ${AWS_SECRET_ACCESS_KEY}

It is also possible to have more than one configuration, so that each service has its own configuration. In this case, additional AWS configuration sets are placed in dbos-config.yaml:

 my_aws_config_for_ses:
  aws_region: us-east-2
  aws_access_key_id: ${AWS_ACCESS_KEY_ID_SES}
  aws_secret_access_key: ${AWS_SECRET_ACCESS_KEY_SES}

Then, each communicator library supports a default AWS configuration name, for example SES (Simple Email Service) uses:

 aws_ses_configuration: my_aws_config_for_ses

If the application uses more than one set of credentials for the same service, such as a separate email configuration for sending advertising vs order confirmations, then separate sections will be specified within the application code.

 ses_config_for_marketing:
  aws_region: ${AWS_REGION}
  aws_access_key_id: ${AWS_ACCESS_KEY_ID_SES1}
  aws_secret_access_key: ${AWS_SECRET_ACCESS_KEY_SES1}
 ses_config_for_orders:
  aws_region: ${AWS_REGION}
  aws_access_key_id: ${AWS_ACCESS_KEY_ID_SES1}
  aws_secret_access_key: ${AWS_SECRET_ACCESS_KEY_SES1}

Most AWS services support endpoints. The endpoint may be included in the configuration as desired:

 sqs_for_shipping:
  aws_region: ${AWS_REGION}
  aws_endpoint: ${AWS_ENDPOINT_URL_SQS}
  aws_access_key_id: 'notneededintest'
  aws_secret_access_key: 'notneededintest'

The subsection of application in the configuration file should provide:

export interface AWSCfgFileItem
{
    aws_region?: string,
    aws_endpoint?: string,
    aws_access_key_id?: string,
    aws_secret_access_key?: string,
}

The interpretation of the configuration file entry will be provided in the following interface:

export interface AWSServiceConfig
{
    name: string,
    region: string,
    endpoint?: string,
    credentials: {
      accessKeyId: string,
      secretAccessKey: string,
    },
}

// Loads an AWS configuration by its section name within the `application` part of dbos-config.yaml
function getAWSConfigByName(cfgname: string): AWSServiceConfig

// Reads a key from within dbos-config.yaml and uses the value of that key to load an AWS configuration section
function getConfigForAWSService(svccfgname: string) : AWSServiceConfig