feat: extend project to run as maven plugin

[algomaster99]

Reference: #892

This PR extends the project to be used as a maven plugin. I have added two goals to the maven plugin, mine and repair. However, only a few options are available at the moment. The main objective right now is to release a maven plugin that is used in the demo at EclipseCon 2022.

Design Philosophy

1. We do not want to duplicate the command line spec for both sub-commands. This is to ensure that the CLI and maven plugin behaves exactly the same.

There will be a slight variation in how the parameters are passed in the plugin (no change in CLI). The parameter that follows the -D option in maven cannot be in kebab-case. I did not find an article citing this, but the code is not working if I do so. For example, -Dhandled-rules won't be post-processed by the plugin so we need to pass -DhandledRules

2. We do not want to introduce any breaking changes. The CLI should continue working as before.

Usage of new feature

Before using the plugin, you need to install the plugin locally. Follow these steps to set it up:

1. Have mavenv3.8.6. The repair command does not work on different versions.
2. Run mvn install -DskipUnitTests -DskipIntegrationTests.

mine goal

mvn se.kth.castor:sorald:0.6.1-SNAPSHOT:mine [-DhandledRules]

Run this on any maven project and you should get a list of mined violations. -DhandledRules is optional and it works exactly how it is written here.

repair goal

mvn se.kth.castor:sorald:0.6.1-SNAPSHOT:repair -DruleKey=<>

The ruleKey parameter is required here and again, see its input here . This should also run on any maven project and produce repairs or does nothing if there are no violations found.

ToDo

• Make the CI pass on Windows and MacOS. The plugin works locally on Windows though. Resolved in 6f777a9.
• Try that repair goal works with 3.6.3 as well because I assume this version is used by a majority of people since it is shipped by apt package manager. Resolved in b05ece5 (#898)
• Update documentation

[sonatype-lift]

⚠️ 1 God Class was detected by Lift in this project. Visit the Lift web console for more details.

[algomaster99]

@khaes-kth I have updated the details about the new feature in the description. Do check it out.

[algomaster99]

The tests finally work on Windows and macOS as well. 😌 Time to update the documentation.

[algomaster99]

@khaes-kth @monperrus

Please try out sorald maven-plugin and drop your reviews.

Summary of changes

1. I have managed to extend the Sorald to be used as a maven-plugin. My goal is to make it as analogous as possible to the CLI. Hence, two goals are added - repair and mine. See "Usage of new feature" in the PR description.
2. We also have integration tests now, thanks @cesarsotovalero for the guidance here. -DskipTests has been split into two parameters now -DskipUnitTests and -DskipIntegrationTests. Keep in mind that the integration tests are triggered in much fewer phases than the unit tests so you may not need to pass -DskipIntegrationTests most of the time. You can see how it used in the updated workflow.

Since we are not meeting this week, I will attach demos of the respective goals.
mine.webm
repair.webm

Future work

A lot of work is left, but we can delegate them to later PRs.

• Fix the error message when -DruleKey is not passed. The error message, as of now, suggests passing -Drules instead.
• Release maven-plugin
• Extend option for generating stats-output-file.
• Extend the leftover options. Their priority can be decided later.

Needless to say, the documentation has to be updated whenever deemed necessary.

[algomaster99]

[ERROR] 

Some dependencies of Maven Plugins are expected to be in provided scope.
Please make sure that dependencies listed below declared in POM
have set '<scope>provided</scope>' as well.

The following dependencies are in wrong scope:
 * org.apache.maven:maven-plugin-api:jar:3.8.6:compile
 * org.apache.maven:maven-model:jar:3.8.6:compile
 * org.apache.maven:maven-artifact:jar:3.8.6:compile

Investigate why this "error" is logged while building the maven plugin.

[khesoem]

Awesome PR. Thanks @algomaster99