Ciris AWS SSM

Amazon EC2 Systems Manager (also known as Simple Systems Manager or SSM) support for Ciris.

Enables us to load parameters of type "string" or "secure string" from the SSM parameter store.

See this blog for more information about using SSM's parameter store to manage secrets.

Getting Started

To get started with sbt, simply add the following lines to your build.sbt file.

resolvers += "Kaluza artifactory" at "https://kaluza.jfrog.io/artifactory/maven"

libraryDependencies += "com.ovoenergy" %% "ciris-aws-ssm" % "LATEST_VERSION"

The library is published against cats effect 3, for both Scala 2.12 and 2.13.

Usage

import cats.effect.{IO, IOApp}
import cats.implicits._
import ciris.Secret
import ciris.aws.ssm._

object Main extends IOApp.Simple {

  final case class Config(
     username: String,
     password: Secret[String],
     port: Int,
     apiKey: Option[String]
  )

  def loadConfig: IO[Config] = 
    params[IO].flatMap { param =>
      (
        param("/myapp/password").secret,
        param("/myapp/port").as[Int],
        param("/myapp/api-key").option
        ).parMapN { (password, port, apiKey) =>
        Config(username = "Dave", password = password, port = port, apiKey = apiKey)
      }
    }.load

  override def run: IO[Unit] =
    loadConfig.flatMap(cfg => IO.println(s"Config loaded: $cfg"))

}

The params[F] function returns a ciris ConfigValue loader. On invocation of the (flatMapped) param(name) function, this loader will make a GetParameterRequest to the underlying SsmAsyncClient, (decrypting the value if encrypted).

The params[F] function uses the AWS SDK's default SsmAsyncClient configuration, but there are alternate functions for construction:

import ciris.aws.ssm._
import cats.effect.IO
import software.amazon.awssdk.auth.credentials.DefaultCredentialsProvider
import software.amazon.awssdk.regions.Region
import software.amazon.awssdk.services.ssm.SsmAsyncClient

// use the default client, but with a region
params[IO](Region.EU_WEST_1)

// also define a custom creds provider
val customCreds = DefaultCredentialsProvider.builder().profileName("foo").build()
params[IO](Region.EU_WEST_1, customCreds)

// for most flexibility, configure the entire client yourself
val client = SsmAsyncClient.builder().httpClient(customClient).build()
params[IO](client)

Release

To release a new version use the following commands.

$ ./tag.sh
$ sbt +publish