atsticks/practicalrx

A RxJava workshop to discover this library by migrating a legacy application. DON'T fork or PR this repo as it may be reconstructed from practicalRxOrigin in the future. Needs https://github.com/simonbasle/practicalRxExternal running.

Practical RxJava Workshop

README

This project is the skeleton (and solution) for the PracticalRxjava workshop.

The aim of the workshop is to discover RxJava through a practical example, a legacy application that we want to gradually migrate to a fully asynchronous and reactive app.

The application is a REST API, based on Spring Boot and layered into Controllers and Services. Services call themselves, a database and even external REST APIs.

/!\ This project should only be cloned for the duration of the workshop. It can (and will) be recreated from upstream if feedback warrants it or new features are brought into the workshop. Don't submit issues or PR here but rather in the upstream practicalRxOrigin repo.

You are now doing step1

Pre-requisites

• The workshop application assumes there is a machine running the practicalRxExternal project (usually the workshop's presenter).

PracticalRxExternal: a fake set of "external REST APIs" called by the legacy application. Some of these are unreliable and will simulate timeouts and delays.

• The workshop can also make use of a Couchbase database.

Users can be stored as JSON in a Couchbase database, a key/value and document-oriented NoSQL database for which a fully reactive Java SDK exists.

• Developers will need to copy and edit the configuration files
  • Copy application.main into /src/main/resources/application.properties
  • Copy application.test into /src/test/resources/applications.properties
  • Edit the copied files. Git will ignore them when switching branches.

There's a property to change the IP on which both the fake external APIs and the database will be running (usualy the workshop's presenter).

IPs can also independently be modified (eg. if the attendee wants to run the database on his own machine).

The need for a database can be deactivated (two Users will be created in memory).

Running the Workshop

This is a Maven project, developed and tested with the IntelliJ IDE.

The REST API is fully functional and can be played with (eg. with a REST client like POSTMAN) by running the Main class.

Controllers are unit tested (see /src/test/java) and attendees are encouraged to run tests from within the IDE to check that their modifications at each step are correct.

Step 9 makes a deep change to the Controllers so tests will change at this point. One can checkout branch step9pre to see both the solution to step 8 and the new version of the tests in preparation for step 9.

Each step is described in the ad hoc stepX.md document under /docs.

One can catch up if late or peek at the solution of each step in its associated branch (eg. branch solution/step2 contains the solution to step #2 described in /docs/steps2.md and can be used as a starting point for step #3).