This version is still in development and is not considered stable yet. For the latest stable version, please use Spring Shell 3.3.1! |
Completion
Spring Shell can provide completion proposals for both interactive shell and a command-line. There are differences however as when shell is in interactive mode we have an active instance of a shell meaning it’s easier to provide more programmatic ways to provide completion hints. When shell is purely run as a command-line tool a completion can only be accomplished with integration into OS level shell’s like bash.
Interactive
Hints for completions are calculated with function or interface style
methods which takes CompletionContext
and returns a list of
CompletionProposal
instances. CompletionContext
gives you various
information about a current context like command registration and option.
Generic resolvers can be registered as a beans if those are useful
for all commands and scenarious. For example existing completion
implementation RegistrationOptionsCompletionResolver handles completions
for a option names.
|
static class MyValuesCompletionResolver implements CompletionResolver {
@Override
public List<CompletionProposal> apply(CompletionContext t) {
return Arrays.asList("val1", "val2").stream()
.map(CompletionProposal::new)
.collect(Collectors.toList());
}
}
Option values with builder based command registration can be defined per option.
void dump1() {
CommandRegistration.builder()
.withOption()
.longNames("arg1")
.completion(ctx -> {
return Arrays.asList("val1", "val2").stream()
.map(CompletionProposal::new)
.collect(Collectors.toList());
})
.and()
.build();
}
Option values with annotation based command registration are handled
via ValueProvider
interface which can be defined with @ShellOption
annotation.
static class MyValuesProvider implements ValueProvider {
@Override
public List<CompletionProposal> complete(CompletionContext completionContext) {
return Arrays.asList("val1", "val2").stream()
.map(CompletionProposal::new)
.collect(Collectors.toList());
}
}
Actual ValueProvider
with annotation based command needs to be
registered as a Bean.
@ShellMethod(value = "complete", key = "complete")
public String complete(
@ShellOption(valueProvider = MyValuesProvider.class) String arg1)
{
return "You said " + arg1;
}
Command-Line
Command-line completion currently only support bash and is documented
in a built-in completion
command Completion.