Spring GCP Cloud Tasks library

Spring-gcp-tasks is a small experimental library to integrate GCP Cloud Tasks into Spring projects.

Note: This isn't production tested, but the library is in a finished state.

---

• Installation
• Compatibility
• Properties
• Usage
• Example

---

Installation

Repository: https://maven.pkg.github.com/AurityLab/spring-gcp-tasks

Gradle:

dependencies {
    implementation "com.auritylab:spring-gcp-tasks:0.1.19"
}

Maven:

<dependency>
  <groupId>com.auritylab</groupId>
  <artifactId>spring-gcp-tasks</artifactId>
  <version>0.1.19</version>
</dependency>

Compatibility

This library is compatible with spring cloud Hoxton or higher (at least Hoxton.M2).

For everything below Hoxton.M2 (Greenwich etc.) you have to use google-cloud-bom version 0.99.0-alpha or higher:

Gradle:

dependencyManagement {
    imports {
        mavenBom("org.springframework.cloud:spring-cloud-dependencies:${springCloudVersion}") {
            bomProperty "google-cloud-bom.version", "0.99.0-alpha"
        }
    }
}

Maven:

<dependency>
    <groupId>com.google.cloud</groupId>
    <artifactId>google-cloud-bom</artifactId>
    <version>0.99.0-alpha</version>
    <type>pom</type>
    <scope>import</scope>
</dependency>

<dependencyManagement>
    <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-dependencies</artifactId>
            <version>${spring-cloud.version}</version>
            <type>pom</type>
            <scope>import</scope>
        </dependency>
    </dependencies>
</dependencyManagement>

Replace ${springCloudVersion} with your version (e.g. Greenwich.SR2).

Properties

Prefix for all properties: com.auritylab.spring.gcp.tasks

Property	Default	Required	Type	Description
signature-secret	nothing	yes	String	Used for signing tasks before submitting to Cloud Tasks.
default-project-id	null	no	String?	Used when nothing specified in @CloudTask annotation.
default-location-id	null	no	String?	Used when nothing specified in @CloudTask annotation.
default-queue-id	null	no	String?	Used when nothing specified in @CloudTask annotation.
default-worker-endpoint	null	no	String?	Used when nothing specified in @CloudTask annotation.
default-worker-endpoint-route	"/taskhandler"	default	String	Used when nothing specified in @CloudTask annotation.
default-worker-route	""	default	String	Used when nothing specified in @CloudTask annotation.
skip-cloud-tasks	false	default	Boolean	Task submissions will be sent to the task's worker endpoint directly skipping Cloud Tasks.
skip-task-endpoint	false	default	Boolean	Task will be executed directly without networking (task's execute method blocks until task finished).
queue-id-global-prefix	""	default	String	Prefix used for all queue ids. Useful for testing or staging.

Note on types:
String -> non-nullable
String? -> nullable

Also note that default-worker-endpoint-route and default-worker-route are two different properties. The former is used for the actual route to send the task to (in combination with default-worker-endpoint). The latter is a virtual route to map the task to the right worker.

Usage

There are two annotations for auto configuration:
@EnableCloudTasks and @EnableCloudTasksWithEndpoint

The former enables spring-gcp-tasks functionality, but disables the worker endpoint.

The latter also enables the worker endpoint via a rest controller mapped to the route specified in com.auritylab.spring.gcp.tasks.default-worker-endpoint-route. A configured web server is needed for this.

@SpringBootApplication
// or @EnableCloudTasks to disable worker endpoint
@EnableCloudTasksWithEndpoint
class Application

fun main(args: Array<String>) {
    runApplication<Application>(*args)
}

Example

Writing a task worker:

@CloudTask(route = "/notification")
class NotificationWorker : TaskWorker<NotificationWorker.Payload>(Payload::class) {
    override fun run(payload: Payload, id: UUID) {
        println("New notification task: $payload")
    }

    data class Payload(val str: String)
}

Executing a task with worker above:

class NotificationTest(
    private val notificationWorker: NotificationWorker
) {
    fun execute() {
        notificationWorker.execute(
            NotificationWorker.Payload("test")
        )
    }
}