Baker

Baker is a library that provides a simple and intuitive way to orchestrate microservice-based process flows.

You declare your orchestration logic as a recipe using the Java, Kotlin, or Scala DSL. A recipe consists of interactions (system calls), ingredients (data), and events.

Bakers ability to visualize recipes provides a powerful communication tool that helps product owners, architects, and engineers to have a common understanding of the business process. This feature allows you to easily share your recipe with others, enabling collaboration and feedback.

Baker allows for the reuse of common interactions across different recipes, promoting consistency and reducing duplication. With Baker, you can quickly assemble complex process flows by reusing pre-existing building blocks that have been built by other teams within your company.

Use the list below to learn more about Baker:

• Documentation
  • Concepts: high level concepts and terminology
  • Recipe DSL: how to use the recipe DSL
  • Visualization: how to visualize a recipe
• Baker Talk @ J-Fall 2021: API orchestration taken to the next level

A bird's-eye view of Baker

A recipe is the blueprint of your business process. To create this blueprint you use the Java, Kotlin, or Scala DSL. The examples below demonstrate a recipe for a simple web shop process.

Java DSL

final Recipe recipe=new Recipe("Web shop")
        .withSensoryEvents(
        CustomerInfoReceived.class,
        OrderPlaced.class,
        PaymentMade.class
    )
            .withInteractions(
            InteractionDescriptor.of(ValidateOrder.class),
        InteractionDescriptor.of(ReserveItems.class)
        .withRequiredEvent(PaymentMade.class),
        InteractionDescriptor.of(ShipGoods.class),
        InteractionDescriptor.of(SendInvoice.class)
        .withRequiredEvent(GoodsShipped.class)
        )
        .withDefaultFailureStrategy(
        new RetryWithIncrementalBackoffBuilder()
        .withInitialDelay(Duration.ofMillis(100))
        .withDeadline(Duration.ofHours(24))
        .withMaxTimeBetweenRetries(Duration.ofMinutes(10))
        .build());

Kotlin DSL

val recipe = recipe("Web shop") {
    sensoryEvents {
        event<CustomerInfoReceived>()
        event<OrderPlaced>()
        event<PaymentMade>()
    }
    interaction<ValidateOrder>()
    interaction<ReserveItems> {
        requiredEvents {
            event<PaymentMade>()
        }
    }
    interaction<ShipGoods>()
    interaction<SendInvoice> {
        requiredEvents {
            event<GoodsShipped>()
        }
    }
    defaultFailureStrategy = retryWithIncrementalBackoff {
        initialDelay = 100.milliseconds
        until = deadline(24.hours)
        maxTimeBetweenRetries = 10.minutes
    }
}

Scala DSL

val recipe: Recipe = Recipe("Web shop")
  .withSensoryEvents(
    Event[CustomerInfoReceived],
    Event[OrderPlaced],
    Event[PaymentMade]
  )
  .withInteractions(
    ValidateOrder,
    ReserveItems
      .withRequiredEvent(Event[PaymentMade])
      ShipGoods,
    SendInvoice
      .withRequiredEvent(goodsShipped)
  )
  .withDefaultFailureStrategy(
    RetryWithIncrementalBackoff
      .builder()
      .withInitialDelay(100 milliseconds)
      .withUntil(Some(UntilDeadline(24 hours)))
      .withMaxTimeBetweenRetries(Some(10 minutes))
      .build()
  )

Visualization

Events are gray, ingredients orange, and interactions lilac:

Getting Started

Baker is released to Maven Central. To use Baker you need three modules.

1. recipe-dsl: DSL to describe recipes in a declarative manner
2. compiler: Compiles recipes into models the runtime can execute
3. runtime: The runtime to manage and execute recipes

Note If you want to use the Kotlin DSL add baker-recipe-dsl-kotlin_2.13 instead of baker-recipe-dsl_2.13.

Maven

<dependency>
    <groupId>com.ing.baker</groupId>
    <artifactId>baker-recipe-dsl_2.13</artifactId>
    <version>4.1.0</version>
</dependency>
<dependency>
    <groupId>com.ing.baker</groupId>
    <artifactId>baker-compiler_2.13</artifactId>
    <version>4.1.0</version>
</dependency>
<dependency>
    <groupId>com.ing.baker</groupId>
    <artifactId>baker-runtime_2.13</artifactId>
    <version>4.1.0</version>
</dependency>

Gradle

implementation 'com.ing.baker:baker-recipe-dsl_2.13:4.1.0'
implementation 'com.ing.baker:baker-compiler_2.13:4.1.0'
implementation 'com.ing.baker:baker-runtime_2.13:4.1.0'

Scala SBT

Baker gets compiled and released for both 2.13.

libraryDependencies += "com.ing.baker" % "baker-recipe-dsl_2.13" % "4.1.0"
libraryDependencies += "com.ing.baker" % "baker-compiler_2.13" % "4.1.0"
libraryDependencies += "com.ing.baker" % "baker-runtime_2.13" % "4.1.0"

Contributing

We welcome your contributions! The simplest way to contribute to Baker is by creating a branch from a fork. You can then create a pull request on GitHub from your branch.

Compile and test

To compile and test all libraries:

sbt 
> compile
> test

To cross compile all libraries for Scala 2.12 and 2.13:

sbt
> +compile
> +test

Compile or test a single project

To build a single project (baker-akka-runtime, baker-anotations, etc...):

1. Find the name of the project by running:

sbt 
> projects

2. Open the desired project via sbt:

sbt
> project <PROJECT_NAME>
> compile
> test