Console application builder

Simple console application builder with support for testing. Created in the context of the social network kata.

Getting started

To use the console, you must provide a list of command builders and a map of formatters.

import java.util.List;
import java.util.Map;

import cat.champel.console.ConsoleApp;

public class ExampleConsoleApp extends ConsoleApp {
	public ExampleConsoleApp() {
		super(
			List.of(
				new Action1CommandBuilder(),
				new Action2CommandBuilder()
			),
			Map.of(
				OutputExample.class, new OutputFormatter()
			)
		);
	}
	
	public static void main(String[] args) {
		new SocialConsoleApp().run();
	}
}

The CommandBuilder parses the input introduced by the user and optionally returns a Command. The command has an execute method that will optionally return an output.

import java.util.Optional;

import cat.champel.console.Command;
import cat.champel.console.CommandBuilder;

public class Action1CommandBuilder implements CommandBuilder {
	public static final String ARROW = " -> ";

	@Override
	public Optional<Command> build(String userCommand) {
		if (!userCommand.contains(ARROW)) return Optional.empty();
		String[] components = userCommand.split(ARROW);
		String userName = components[0];
		String message = components[1];
		return Optional.of(() -> Optional.of(userName + " posted: " + message));
	}
}

Testing

The library also incorporates a ConsoleAppTester that includes setup, writeCommand and readOutput to facilitate the testing of a console.

Here an example of glue code of a cucumber test using the tester:

import static org.assertj.core.api.Assertions.assertThat;

import java.io.IOException;

import cat.champel.console.ConsoleAppTester;
import io.cucumber.java8.En;

public class ConsoleAppE2EATStepsDef extends ConsoleAppTester implements En {
	public ConsoleAppE2EATStepsDef() {
		Before(() -> setup(new SocialConsoleApp()));
		Given("in:  > {string}", (String command) -> processInput(command));
		Then( "out: {string}", (String chars) -> assertOutput(chars.replace("\\n","\n")));
	}

	private void processInput(String command) throws Exception, IOException {
		assertOutput(PROMPT);
		writeCommand(command);
	}
	
	private void assertOutput(String expected) throws Exception {
		assertThat(readOutput(expected)).isEqualTo(expected);
	}
}

More examples in the social network kata.