Floci Dev Service

A service providing Floci, a free open-source local AWS emulator, for development and testing purposes.

It works with Spring Boot libraries that support AWS, including:

The Dev Service brings the core of Spring Cloud AWS with it, including its support for connecting to Floci. Add the Spring Cloud AWS starter of each AWS service your application uses, such as io.awspring.cloud:spring-cloud-aws-starter-s3: the AWS endpoint, region, and credentials of its clients are configured automatically.

Floci exposes a single HTTP endpoint for all emulated AWS services. When using Spring Cloud AWS S3, path-style access is automatically enabled by the Dev Service.

This Dev Service is mutually exclusive with other AWS dev services. If more than one is active at the same time, the application will fail at startup with a clear error message. Disable all but one by setting arconia.dev.services.<name>.enabled=false.

Dependencies

First, you need to add the Dev Service dependency to your project.

  • Gradle

  • Maven

dependencies {
  testAndDevelopmentOnly "io.arconia:arconia-dev-services-floci"
}
<dependency>
    <groupId>io.arconia</groupId>
    <artifactId>arconia-dev-services-floci</artifactId>
    <scope>runtime</scope>
    <optional>true</optional>
</dependency>

You can optionally include the Spring Boot DevTools dependency to enable live reload of your application during development.

  • Gradle

  • Maven

dependencies {
  developmentOnly "org.springframework.boot:spring-boot-devtools"
}
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-devtools</artifactId>
    <scope>runtime</scope>
    <optional>true</optional>
</dependency>

When you use the Spring Boot DevTools in your project and run the application in dev mode, Arconia keeps the Dev Services running while you make changes to your code instead of restarting them with the application. This allows you to see the changes in real-time without having to restart the Dev Services. Changes to the configuration of a Dev Service take effect once you stop and start the application again.

Running the Application

When using the Arconia Dev Services, you can keep running your application as you normally would. The Dev Services will automatically start when you run your application.

  • Gradle

  • Maven

  • CLI

./gradlew bootRun
./mvnw spring-boot:run
arconia dev
Unlike the lower-level Testcontainers support in Spring Boot, Arconia doesn’t require special tasks to run your application when using Dev Services (./gradlew bootTestRun or ./mvnw spring-boot:test-run) nor requires you to define a separate @SpringBootApplication class for configuring Testcontainers.

Your integration tests based on @SpringBootTest will automatically use the Dev Services without any additional configuration.

Test slices (e.g. @DataJdbcTest) load only a subset of the auto-configurations, so they don’t pick up Dev Services automatically. You can import the Dev Service explicitly. For example, for the PostgreSQL Dev Service:

@DataJdbcTest
@AutoConfigureTestDatabase(replace = Replace.NONE)
@Import(PostgresqlDevServicesAutoConfiguration.class)
class CustomerRepositoryTests {
    ...
}

By default, each application starts its own Floci Dev Service. To let multiple applications running simultaneously in dev mode use the same one, set the arconia.dev.services.floci.reuse-strategy property to framework: the application connects to a running Floci Dev Service started by another application if available, or else starts its own that other applications can discover in turn. The applications using the same Dev Service must use the same region. Learn more about Reusing Dev Services.

Configuring the Dev Service

You can configure the Dev Service via configuration properties.

Property Default Description

arconia.dev.services.floci.enabled

true

Whether the dev service is enabled.

arconia.dev.services.floci.image-name

floci/floci

Full name of the container image used in the dev service.

arconia.dev.services.floci.environment

{}

Environment variables to set in the service.

arconia.dev.services.floci.network-aliases

[]

Additional hostnames the dev service container is reachable by on the shared network, next to the name of the dev service. Only applicable when the shared network is enabled.

arconia.dev.services.floci.port

0

Fixed port for exposing the Floci port to the host. When it’s 0 (default), a random available port is assigned dynamically.

arconia.dev.services.floci.resources

[]

Resources from the classpath or host filesystem to copy into the container. They can be files or directories that will be copied to the specified destination path inside the container at startup and are immutable (read-only).

arconia.dev.services.floci.reuse-strategy

none

Strategy for reusing a running container for the dev service instead of starting a new one. With framework, the dev service is discoverable by other applications, and the application connects to an existing dev service if available. With testcontainers, the container is kept running across application restarts, relying on the Testcontainers reusable containers feature, which must be enabled in the ~/.testcontainers.properties file; such containers are not stopped automatically and must be cleaned up manually. Only applicable in dev mode.

arconia.dev.services.floci.startup-timeout

30s

Maximum waiting time for the service to start, counted from the container start.

arconia.dev.services.floci.volumes

[]

Files or directories to mount from the host filesystem into the container. They are mounted at the specified destination path inside the container at startup and are mutable (read-write). Changes in either the host or the container will be immediately reflected in the other.

You can enable/disable the Dev Service selectively for a specific application mode (development, test), relying on one of the profiles which are automatically configured by Arconia (see Profiles).

You can enable/disable the Dev Service for a specific test class by using the @TestPropertySource annotation or equivalent Spring testing utilities.