IDDD_NYSE

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The IDDD_NYSE repository contains a set of projects that reflect my take on the SpringTrader project (formerly NanoTrader). It's my attempt to improve the model using a DDD approach.

This is a work in progress. The various Bounded Contexts (iddd_nanotrader, iddd_algotrader, iddd_nanoreports) and the Supporting Subdomains and reusable tools found in iddd_tradercommon are not complete. In particular when a market order and a slice order are executed, the requests just fall off a cliff. Currently the models go no further than to track the number of shares conceptually purchased, and that's it. There are other holes in the models, too, and it will require more time with my volunteer domain expert before this effort provides a more realistic simulation of stock purchases.

In all this example provides a fairly decent look at Aggregate design and the use of Domain Events in a simple Event-Driven Architecture. Actually none of the Events are currently crossing Context boundaries. Still, you can look at the tests to see how the Events would be handled if the Bounded Contexts were actually deployed. You can also see a bit of Published Language in the Notifications that (would) arrive in the iddd_algotrader and iddd_nanotrader Bounded Contexts.

Note that the Account Subdomain in iddd_nanotrader has lost its way. This should (very likely) be in its own Bounded Context. It seems like many trading providers are full-on financial services organizations, and user accounts may include checking, savings, 401K, etc., in addition to a standard brokerage/trading account. Yet, leaving the Account Subdomain in this model allows me to use it to teach some Context Mapping and Subdomain identification techniques in class. It's a darling of a legacy smell, even though I have cleaned up the model substantially compared to the original.

I created a simple Pub-Sub messaging mechanism that I named SlothMQ. (Yeah.) The tests that run the Sloth are a bit slow since they pause to allow time for the creature to scoot messages across the wire like a sloth drags its butt across the ground. Anyway, it works, if even at a slothful rate, and it can be run just about anywhere.

The run the tests:

1. Install Java SDK 1.7.?
2. Install Gradle 1.5 (doing all the GRADLE_HOME and PATH set up)
3. Grab the code using git into a project root named IDDD_NYSE
4. In the IDDD_NYSE root, run: gradle clean build

That's just about it. You should see the gradle test output in each of the subprojects:

iddd_algotrader/build/reports/tests/index.html iddd_nanoreports/build/reports/tests/index.html iddd_nanotrader/build/reports/tests/index.html iddd_tradercommon/build/reports/tests/index.html

Actually iddd_nanoreports doesn't do anything yet. It's just a placeholder to remove the reporting type things from the iddd_nanotrader Bounded Context. This may change quite a bit by the time it's done.

If you get a chance to help, I welcome your participation!

Vaughn Vernon Author: Implementing Domain-Driven Design