/**
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.karaf.shell.console;
import java.io.PrintStream;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.util.Map;
import java.util.Set;
import java.util.SortedMap;
import java.util.TreeMap;
import jline.Terminal;
import org.apache.felix.gogo.commands.Action;
import org.apache.felix.gogo.commands.Argument;
import org.apache.felix.gogo.commands.Command;
import org.apache.felix.gogo.commands.basic.AbstractCommand;
import org.apache.felix.gogo.commands.basic.DefaultActionPreparator;
import org.apache.felix.service.command.Function;
import org.fusesource.jansi.Ansi;
import org.osgi.framework.BundleContext;
import org.osgi.framework.ServiceReference;
/**
* Displays help on the available commands
*/
@Command(scope = "*", name = "help", description = "Displays this help or help about a command")
public class HelpAction extends AbstractAction {
@Argument(name = "command", required = false, description = "The command to get help for")
private String command;
public Object doExecute() throws Exception {
if (command == null) {
Set<String> names = (Set<String>) session.get(".commands");
if (!names.isEmpty()) {
Terminal term = (Terminal) session.get(".jline.terminal");
PrintStream out = System.out;
SortedMap<String,String> commands = new TreeMap<String,String>();
for (String name : names) {
String description = null;
Function function = (Function) session.get(name);
function = unProxy(function);
if (function instanceof AbstractCommand) {
try {
Method mth = AbstractCommand.class.getDeclaredMethod("createNewAction");
mth.setAccessible(true);
Action action = (Action) mth.invoke(function);
Class<? extends Action> clazz = action.getClass();
Command ann = clazz.getAnnotation(Command.class);
description = ann.description();
} catch (Throwable e) {
}
if (name.startsWith("*:")) {
name = name.substring(2);
}
commands.put(name, description);
}
}
// Post process the commands list
out.println(Ansi.ansi().a(Ansi.Attribute.INTENSITY_BOLD).a("COMMANDS").a(Ansi.Attribute.RESET));
for (Map.Entry<String,String> entry : commands.entrySet()) {
out.print(" ");
String key = NameScoping.getCommandNameWithoutGlobalPrefix(session, entry.getKey());
out.println(Ansi.ansi().a(Ansi.Attribute.INTENSITY_BOLD).a(key).a(Ansi.Attribute.RESET));
if (entry.getValue() != null) {
DefaultActionPreparator.printFormatted(" ", entry.getValue(), term != null ? term.getWidth() : 80, out);
}
}
out.println();
}
return null;
} else {
return session.execute(command + " --help");
}
}
protected Function unProxy(Function function) {
try {
if (function.getClass().getName().contains("CommandProxy")) {
Field contextField = function.getClass().getDeclaredField("context");
Field referenceField = function.getClass().getDeclaredField("reference");
contextField.setAccessible(true);
referenceField.setAccessible(true);
BundleContext context = (BundleContext) contextField.get(function);
ServiceReference reference = (ServiceReference) referenceField.get(function);
Object target = context.getService(reference);
try {
if (target instanceof Function) {
function = (Function) target;
}
} finally {
context.ungetService(reference);
}
}
} catch (Throwable t) {
}
return function;
}
}