Add support for command aliases

Author: fmbenhassine

spring-shell-core/src/main/java/org/springframework/shell/core/command/Command.java

@@ -153,8 +153,7 @@ public AbstractCommand execute(Consumer<CommandContext> commandExecutor) {
 
 			ConsumerCommandAdapter command = new ConsumerCommandAdapter(name, description, group, help, hidden,
 					commandExecutor);
-
-			initAliases(command);
+			command.setAliases(aliases);
 
 			return command;
 		}
@@ -164,18 +163,11 @@ public AbstractCommand execute(Function<CommandContext, String> commandExecutor)
 
 			FunctionCommandAdapter command = new FunctionCommandAdapter(name, description, group, help, hidden,
 					commandExecutor);
-
-			initAliases(command);
+			command.setAliases(aliases);
 
 			return command;
 		}
 
-		private void initAliases(AbstractCommand command) {
-			if (aliases != null) {
-				command.setAliases(aliases);
-			}
-		}
-
 	}
 
 }

spring-shell-core/src/main/java/org/springframework/shell/core/command/CommandRegistry.java

@@ -62,7 +62,18 @@ public Set<Command> getCommands() {
 			.filter(command -> !command.isHidden())
 			.filter(command -> command.getName().equals(name))
 			.findFirst()
-			.orElse(null);
+			.orElseGet(() -> getCommandByAlias(name));
+	}
+
+	@Nullable public Command getCommandByAlias(String name) {
+		return commands.stream().filter(command -> !command.isHidden()).filter(command -> {
+			for (String alias : command.getAliases()) {
+				if (alias.equals(name)) {
+					return true;
+				}
+			}
+			return false;
+		}).findFirst().orElse(null);
 	}
 
 	public List<Command> getCommandsByPrefix(String prefix) {
@@ -72,6 +83,7 @@ public List<Command> getCommandsByPrefix(String prefix) {
 			.toList();
 	}
 
+	// TODO check alias conflicts when registering commands
 	public void registerCommand(Command command) {
 		commands.add(command);
 	}

spring-shell-core/src/main/java/org/springframework/shell/core/command/annotation/Command.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2023-2024 the original author or authors.
+ * Copyright 2023-present the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -51,12 +51,11 @@
 	String[] name() default {};
 
 	/**
-	 * Define alias as an array. Given that alias should be {@code alias1 sub1} it can be
-	 * defined as:
+	 * Define aliases as an array that can be defined as:
 	 *
 	 * <pre class="code">
-	 * alias = { "alias1", "sub1" }
-	 * alias = "alias1 sub1"
+	 * alias = { "alias1", "alias2" }
+	 * alias = "alias1 alias2"
 	 * </pre>
 	 *
 	 * Values are split and trimmed meaning spaces doesn't matter.

spring-shell-core/src/main/java/org/springframework/shell/core/command/annotation/support/CommandFactoryBean.java

@@ -16,6 +16,7 @@
 package org.springframework.shell.core.command.annotation.support;
 
 import java.lang.reflect.Method;
+import java.util.Arrays;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
@@ -59,12 +60,12 @@ public Command getObject() {
 		org.springframework.shell.core.command.annotation.Command command = MergedAnnotations.from(this.method)
 			.get(org.springframework.shell.core.command.annotation.Command.class)
 			.synthesize();
-		// TODO handle aliases
 		String name = String.join(" ", command.name());
 		String description = command.description();
 		String help = command.help();
 		String group = command.group();
 		boolean hidden = command.hidden();
+		String[] aliases = command.alias();
 		log.debug("Creating command bean for method '" + this.method + "' with name '" + name + "'");
 		Class<?> declaringClass = this.method.getDeclaringClass();
 		Object targetObject;
@@ -87,8 +88,10 @@ Ensure that the declaring class is annotated with a Spring stereotype annotation
 		catch (BeansException e) {
 			log.debug("No ConfigurableConversionService bean found, using a default conversion service.");
 		}
-		return new MethodInvokerCommandAdapter(name, description, group, help, hidden, this.method, targetObject,
-				configurableConversionService);
+		MethodInvokerCommandAdapter methodInvokerCommandAdapter = new MethodInvokerCommandAdapter(name, description,
+				group, help, hidden, this.method, targetObject, configurableConversionService);
+		methodInvokerCommandAdapter.setAliases(Arrays.stream(aliases).toList());
+		return methodInvokerCommandAdapter;
 	}
 
 	@Override

spring-shell-core/src/test/java/org/springframework/shell/core/command/CommandRegistryTests.java

@@ -124,4 +124,38 @@ public ExitStatus execute(CommandContext commandContext) {
 		assertTrue(commands.stream().anyMatch(cmd -> cmd.getName().equals("status")));
 	}
 
+	@Test
+	void getCommandByAlias() {
+		// given
+		commandRegistry.registerCommand(new Command() {
+
+			@Override
+			public String getName() {
+				return "list";
+			}
+
+			@Override
+			public java.util.List<String> getAliases() {
+				return java.util.List.of("ls", "dir");
+			}
+
+			@Override
+			public ExitStatus execute(CommandContext commandContext) {
+				return ExitStatus.OK;
+			}
+		});
+
+		// when
+		Command cmdLs = commandRegistry.getCommandByAlias("ls");
+		Command cmdDir = commandRegistry.getCommandByAlias("dir");
+		Command cmdUnknown = commandRegistry.getCommandByAlias("unknown");
+
+		// then
+		assertNotNull(cmdLs);
+		assertEquals("list", cmdLs.getName());
+		assertNotNull(cmdDir);
+		assertEquals("list", cmdDir.getName());
+		assertNull(cmdUnknown);
+	}
+
 }