DevOps lab
The Lagom framework includes Java and Scala APIs to simplify development of microservices. Industry-standard build tools automatically download what you need to get started developing a Lagom system. Use a Maven archetype or an sbt template to create a new project with a simple Hello World service that you can test in your browser.
One simple command starts the Lagom development environment and runs:
- Cassandra
- Kafka
- A service locator
- A service gateway
- Your Lagom services
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Create a new directory for your project.
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Change into the new directory and enter the following (all on one line):
mvn archetype:generate -DarchetypeGroupId=com.lightbend.lagom
-DarchetypeArtifactId=maven-archetype-lagom-java -DarchetypeVersion=1.3.4
- Maven prompts you for:
groupId - typically something like com.example.
artifactId - becomes the top-level folder name, for example, my-first-project.
version - the version for your project, press Enter to accept the default.
package - defaults to the same value as the groupId
Define value for property 'groupId': com.schneeheld
Define value for property 'artifactId': lagom-lab
Define value for property 'version' 1.0-SNAPSHOT: :
Define value for property 'package' com.schneeheld: :
[INFO] Using property: service1ClassName = Hello
[INFO] Using property: service1Name = hello
[INFO] Using property: service2ClassName = Stream
[INFO] Using property: service2Name = stream
Confirm properties configuration:
groupId: com.schneeheld
artifactId: lagom-lab
version: 1.0-SNAPSHOT
package: com.schneeheld
service1ClassName: Hello
service1Name: hello
service2ClassName: Stream
service2Name: stream
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Enter Y to accept the values. Maven creates the project.
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Change into the top-level project folder and run it:
mvn lagom:runAll
The runAll command takes a bit of time. It starts Hello World microservices and registers them in a service directory.
It also starts a Cassandra server and a web server.
- When you see the message
Services started ..., invoke the hello service endpoint from any HTTP client http://localhost:9000/api/hello/World The request returns the message Hello, World!.