Add alias for description attribute in Command annotation

[ullenboom]

Over the last major versions, Spring Shell introduced several breaking conceptual and syntactic changes:

• @ShellComponent → @Component
• @ShellMethod → @Command
• Description has to be set via annotation attribute
• @Argument and @Option are now mandatory
• -- is now required for command invocation

The first set of changes is understandable. But ...

An alias for description would be nice (restore to SS 3 behavior):

public @interface Command {

	/**
	 * Alias for {@link #description()}.
	 * Allows using {@code @Command("...")} as shorthand.
	 */
	@AliasFor("description")
	String value() default "";

	/**
	 * Define a command description.
	 * @return the command description
	 */
	@AliasFor("value")
	String description() default "";
...
}

As noted in #1287, it should be possible to omit the @Argument annotation.

If a command has no subcommands and the invocation is unambiguous, the -- separator should be optional (behavior as in SS 3). The documentation seems to point to writing a custom parser; if so, that feels like a workaround rather than a general solution.

Overall, simplifying these cases would reduce the number of required changes in existing code. Otherwise, the mandatory use of -- forces updates to user-facing documentation in every project that relies on Spring Shell.

[fmbenhassine]

Thank you for opening this issue.

An alias for description would be nice (restore to SS 3 behavior):

There is no alias for description in v3: https://github.com/spring-projects/spring-shell/blob/3.4.x/spring-shell-core/src/main/java/org/springframework/shell/command/annotation/Command.java

The following does not compile in a v3 app:

@Command("say hello")
public String hello() {
    return "Hello !";
}

But I will consider it as an improvement in v4.0.1.

As noted in #1287, it should be possible to omit the @argument annotation.
If a command has no subcommands and the invocation is unambiguous, the -- separator should be optional (behavior as in SS 3). The documentation seems to point to writing a custom parser; if so, that feels like a workaround rather than a general solution.

Overall, simplifying these cases would reduce the number of required changes in existing code. Otherwise, the mandatory use of -- forces updates to user-facing documentation in every project that relies on Spring Shell.

This was fixed in #1287 and will be shipped in 4.0.1

---

I edited the title of this issue to focus on the alias for description improvement.

[ullenboom]

Thank you for opening this issue.

An alias for description would be nice (restore to SS 3 behavior):

There is no alias for description in v3: https://github.com/spring-projects/spring-shell/blob/3.4.x/spring-shell-core/src/main/java/org/springframework/shell/command/annotation/Command.java

The following does not compile in a v3 app:

@command("say hello")
public String hello() {
return "Hello !";
}
But I will consider it as an improvement in v4.0.1.

I was comparing this to @ShellMethod, not @Command.

[ullenboom]

Excellent

[fmbenhassine]

I was comparing this to @ShellMethod, not @Command.

OK I see. No problem, thank you for the feedback.