Growing Object-Oriented Software, Guided by Tests

Auction Sniper example re-creation

The commit history of this repository presents a step-by-step re-creation of the auction sniper example project from the book Growing Object-Oriented Software, Guided by Tests by Steve Freeman and Nat Pryce.

Features of this repository

follows the book closely
page number and description in each commit message
uses code from the authors' repository to fill in parts omitted from the book (https://github.com/sf105/goos-code)
changes are broken down into small, logical commits, even where the narrative in the book mentions multiple refactorings in a sentence
commits in between writing and passing tests allow you to see the failure messages for instructional purposes
Gradle is used for dependency management and build
complete--includes all steps and code from chapters 10 through 19

Notes

This repository aims to faithfully present the printed code. However there are many minor inconsistencies in the printed code that would prevent it from working verbatim. I consulted the authors' own repository (https://github.com/sf105/goos-code) to resolve ambiguities and conflicts. I liberally copied code from their repository to fill in portions that were omitted from the book but mentioned in passing or implied by the code shown. Since the authors' repository only shows the final form of the code, sometimes it was necessary to make an educated guess about the code's form at the point it's introduced in the narrative.

Although the book states that code should never be committed with failing unit tests (p. 8), the purpose of this repository is instructional, so there are many commits with failing tests so you can see the messages. In a few commits, not all the code compiles--just enough to run the tests in question.

Where a set of changes is spread across multiple pages, the page number in the commit message is the last page on which code of that set appears.

Openfire installation & configuration

The example requires a local XMPP server running. The book uses Openfire. I used a more recent version than the book (4.0.3, dated August 2016). I simply downloaded the ZIP file distribution, unzipped it, and ran startup.jar from the command line. With the default configuration you should be able to connect to the web admin console at localhost:9090. From there, follow the guidance in the book on p. 89. In particular:

During initial setup:
- set host/server name to localhost
- on the Database Settings screen select Embedded Database
After initial setup:
- on the Users/Groups tab, create the 3 users specified in the book
- under Server -> Server Settings -> Resource Policy, set Conflict Policy to Never kick
- under Server -> Server Settings -> Offline Messages, select Drop
Optionally disable anonymous auth and unneeded services (for security nuts like me):
- Server Manager tab
  - System Properties -> xmpp.auth.anonymous = false
- Server Settings tab
  - Registration & Login -> disable inband account registration, change password, and anonymous login
  - Server to Server -> Plain-text (with STARTTLS) connections -> uncheck Enabled
  - External Component Settings -> "Plain-text (with STARTTLS) connections" and "Encrypted (legacy-mode) connections" uncheck
  - Connection Managers -> Disabled
  - HTTP Binding -> Disabled
  - File Transfer Settings -> Proxy Service = disabled
  - Search Service Properties -> Service Enabled = disabled

Building & running

The project includes the Gradle wrapper so you do not need to install Gradle; just invoke the gradlew script. (For *nix, make sure it is executable and invoke it as ./gradlew.)

To compile and run all tests from the command line:

gradlew check

If the tests have already been run successfully and the code has not been changed, Gradle will not re-run the tests when the command is executed repeatedly. If you want to force the tests to re-run:

gradlew cleanTest check

Most likely you'll want to import the code into your IDE. As the project progresses, some dependencies are added, so remember to refresh the dependencies in your IDE from the Gradle file when necessary.

Troubleshooting

If something isn't working as you expected:

Try a clean: gradlew clean (and clean the project in your IDE).
If you get errors about missing classes, refresh your IDE project model from the Gradle file.
If tests are failing or it won't compile, remember that some commits are meant to fail in this way. Look at the commit message and book narrative to figure out what is expected.
End-to-end and some integration tests simulate user input. Do not disturb the keyboard or mouse while they're running.