Just a practice project to experiment with multithreading Java 8 features: A webapp that connects to a crypto exchange REST API and shows the current state of the market.

docker run -p8080:8080 rubenmartinez/stpc

Then point your browser to: https://127.0.0.1:8080 when the log says server is ready. (Note: Microsoft InternetExplorer/Edge are not supported)

Just execute in the base directory:

mvn clean install

Then the server app can be executed with:

java -jar stpc-app-1.0.0.jar

Then point your browser to: https://127.0.0.1:8080 as in the Docker run.

JUnit 5 is used for Unit Testing so mininum Apache Maven version required is 3.3.9. You can always use -DskipTests=true to skip tests compilation and execution. This also speeds up building times considerably.

The effort and focus has been put in testing the most critical logic under all possible conditions, more than trying to get a high percentage of coverage just for the looks, trivial classes have been left as a lower priority while complex classes have much more test coverage (and even with several parametrized conditions that really don't increase the test coverage much).

TODO/Note: tests might fail under some circumstances as they have some assumptions on async code durations using parallel threads, even if the "timeouts" should be high enough, on slow machines a timeout for an async code could trigger so the test is assumed to fail, even if the code is working correctly.

As JUnit 5, old versions of Eclipse or IntelliJ IDEA won't work for testing. At least Eclipse Photon, or IntelliJ IDEA 2016.2 are required.

Actually Eclipse Photon didn't support well JUnit5 in some circumstances. For this project I had to replace $ECLIPSE_HOME/plugins/org.hamcrest.core_1.3.0.v20180420-1519.jar with hamcrest-core-1.3.jar from Maven Repository (See StackOverflow thread)

Originally, the project made extensive use of Lombok to improve final readability and development speed.

The caveat is that the IDE needs to have Lombok installed so all classes can be compiled. Even if installation is really easy, in order to not make it mandatory to install Lombok for the reader, the project have been de-lomboked, that why many classes have a comment Generated by delombok at XXX

The project is divided into 3 modules, so the application and strategies are decoupled from the actual exchange used. With a proper connector a new Exchange implementation different from Bitso could be plugged-in and used with the same application and strategies.

Basic interfaces that represent a generic exchange. (Actually this module contains only the method needed for the exercise).

Bitso implementation for module stpc-exchange.

An effort has been made to not use Spring nor any big framework in this library so it is kept as lightweight as possible, so it can be used in another projects reducing risk of version incompatibilities or conflicts. (Some reference articules: DZone or Jooq)

It is intended to be highly concurrent trying to use fine-grained locks as specific as possible.

It is a SpringBoot application which starts a web server and publish two REST Endpoints:

• /api/v1/strategies/: Strategy management. It can reconfigure or show nice statistics about a running strategy (see in the current app example: (https://localhost:8080/api/v1/strategies/contrarian1)). This REST Controller would normally also create more Strategy instances of a given type on http POST method, etc...
• /api/v1/exchange/: Can be requested about best asks, best bids and last trades.

It also contains the FE files and the "Strategy framework" (with just a ContrarianStrategy as Strategy type)