README.md

Header Manipulation and HTTP testing

This project demonstrates how to manipulate HTTP headers and response Status codes using Lagom. It also demonstrates how to write tests that assert the low-level HTTP dialogue (headers, status codes, etc...) is what you expect.

The code base contains only two classes of interest:

• HelloServiceImpl.java implements an endpoint which reads requests headers. It also manipulates response headers and status codes. There's more information on how to do that in Lagom docs. In this example, the header manipulation is used to implement a naïve caching mechanism that uses HTTP headers to control the client cache.
• HelloServiceTest.java tests the behavior in HelloServiceImpl.java using Lagom's client for the happy path and a non-Lagom HTTP client (in this case a plain java.net.HttpUrlConnection) to access all the fields on the low-level HTTP protocol.

How to run

In one terminal use:

sbt runAll

Then, in a second terminal use:

curl http://localhost:9000/api/hello/Alice -v 
curl http://localhost:9000/api/hello/Alice -v  -H 'If-None-Match: "some-value-stored-in-db-or-persistent-entity"'
curl http://localhost:9000/api/hello/Alice -v  -H 'If-None-Match: "invalid-etag"'

To stop the service, kill the sbt runAll process using Ctrl-C.

How to run the tests

In a terminal use:

sbt test