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*
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package hudson.cli;
import hudson.AbortException;
import hudson.Extension;
import hudson.ExtensionList;
import hudson.ExtensionPoint;
import hudson.cli.declarative.CLIMethod;
import hudson.ExtensionPoint.LegacyInstancesAreScopedToHudson;
import hudson.cli.declarative.OptionHandlerExtension;
import hudson.model.Hudson;
import hudson.remoting.Callable;
import hudson.remoting.Channel;
import hudson.remoting.ChannelProperty;
import hudson.security.CliAuthenticator;
import hudson.security.SecurityRealm;
import org.acegisecurity.Authentication;
import org.acegisecurity.context.SecurityContext;
import org.acegisecurity.context.SecurityContextHolder;
import org.jvnet.hudson.annotation_indexer.Index;
import org.jvnet.tiger_types.Types;
import org.kohsuke.args4j.ClassParser;
import org.kohsuke.args4j.CmdLineException;
import org.kohsuke.args4j.CmdLineParser;
import org.kohsuke.args4j.spi.OptionHandler;
import java.io.BufferedInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintStream;
import java.lang.reflect.Type;
import java.util.List;
import java.util.Locale;
import java.util.logging.Logger;
/**
* Base class for Hudson CLI.
*
* <h2>How does a CLI command work</h2>
* <p>
* The users starts {@linkplain CLI the "CLI agent"} on a remote system, by specifying arguments, like
* <tt>"java -jar hudson-cli.jar command arg1 arg2 arg3"</tt>. The CLI agent creates
* a remoting channel with the server, and it sends the entire arguments to the server, along with
* the remoted stdin/out/err.
*
* <p>
* The Hudson master then picks the right {@link CLICommand} to execute, clone it, and
* calls {@link #main(List, Locale, InputStream, PrintStream, PrintStream)} method.
*
* <h2>Note for CLI command implementor</h2>
* Start with <a href="http://wiki.hudson-ci.org/display/HUDSON/Writing+CLI+commands">this document</a>
* to get the general idea of CLI.
*
* <ul>
* <li>
* Put {@link Extension} on your implementation to have it discovered by Hudson.
*
* <li>
* Use <a href="http://java.net/projects/args4j/">args4j</a> annotation on your implementation to define
* options and arguments (however, if you don't like that, you could override
* the {@link #main(List, Locale, InputStream, PrintStream, PrintStream)} method directly.
*
* <li>
* stdin, stdout, stderr are remoted, so proper buffering is necessary for good user experience.
*
* <li>
* Send {@link Callable} to a CLI agent by using {@link #channel} to get local interaction,
* such as uploading a file, asking for a password, etc.
*
* </ul>
*
* @author Kohsuke Kawaguchi
* @since 1.302
* @see CLIMethod
*/
@LegacyInstancesAreScopedToHudson
public abstract class CLICommand implements ExtensionPoint, Cloneable {
/**
* Connected to stdout and stderr of the CLI agent that initiated the session.
* IOW, if you write to these streams, the person who launched the CLI command
* will see the messages in his terminal.
*
* <p>
* (In contrast, calling {@code System.out.println(...)} would print out
* the message to the server log file, which is probably not what you want.
*/
public transient PrintStream stdout,stderr;
/**
* Connected to stdin of the CLI agent.
*
* <p>
* This input stream is buffered to hide the latency in the remoting.
*/
public transient InputStream stdin;
/**
* {@link Channel} that represents the CLI JVM. You can use this to
* execute {@link Callable} on the CLI JVM, among other things.
*/
public transient Channel channel;
/**
* The locale of the client. Messages should be formatted with this resource.
*/
public transient Locale locale;
/**
* Gets the command name.
*
* <p>
* For example, if the CLI is invoked as <tt>java -jar cli.jar foo arg1 arg2 arg4</tt>,
* on the server side {@link CLICommand} that returns "foo" from {@link #getName()}
* will be invoked.
*
* <p>
* By default, this method creates "foo-bar-zot" from "FooBarZotCommand".
*/
public String getName() {
String name = getClass().getName();
name = name.substring(name.lastIndexOf('.')+1); // short name
name = name.substring(name.lastIndexOf('$')+1);
if(name.endsWith("Command"))
name = name.substring(0,name.length()-7); // trim off the command
// convert "FooBarZot" into "foo-bar-zot"
// Locale is fixed so that "CreateInstance" always become "create-instance" no matter where this is run.
return name.replaceAll("([a-z0-9])([A-Z])","$1-$2").toLowerCase(Locale.ENGLISH);
}
/**
* Gets the quick summary of what this command does.
* Used by the help command to generate the list of commands.
*/
public abstract String getShortDescription();
public int main(List<String> args, Locale locale, InputStream stdin, PrintStream stdout, PrintStream stderr) {
this.stdin = new BufferedInputStream(stdin);
this.stdout = stdout;
this.stderr = stderr;
this.locale = locale;
this.channel = Channel.current();
registerOptionHandlers();
CmdLineParser p = new CmdLineParser(this);
// add options from the authenticator
SecurityContext sc = SecurityContextHolder.getContext();
Authentication old = sc.getAuthentication();
CliAuthenticator authenticator = Hudson.getInstance().getSecurityRealm().createCliAuthenticator(this);
new ClassParser().parse(authenticator,p);
try {
p.parseArgument(args.toArray(new String[args.size()]));
Authentication auth = authenticator.authenticate();
if (auth==Hudson.ANONYMOUS)
auth = loadStoredAuthentication();
sc.setAuthentication(auth); // run the CLI with the right credential
if (!(this instanceof LoginCommand || this instanceof HelpCommand))
Hudson.getInstance().checkPermission(Hudson.READ);
return run();
} catch (CmdLineException e) {
stderr.println(e.getMessage());
printUsage(stderr, p);
return -1;
} catch (AbortException e) {
// signals an error without stack trace
stderr.println(e.getMessage());
return -1;
} catch (Exception e) {
e.printStackTrace(stderr);
return -1;
} finally {
sc.setAuthentication(old); // restore
}
}
/**
* Loads the persisted authentication information from {@link ClientAuthenticationCache}.
*/
protected Authentication loadStoredAuthentication() throws InterruptedException {
try {
return new ClientAuthenticationCache(channel).get();
} catch (IOException e) {
stderr.println("Failed to access the stored credential");
e.printStackTrace(stderr); // recover
return Hudson.ANONYMOUS;
}
}
/**
* Determines if the user authentication is attempted through CLI before running this command.
*
* <p>
* If your command doesn't require any authentication whatsoever, and if you don't even want to let the user
* authenticate, then override this method to always return false — doing so will result in all the commands
* running as anonymous user credential.
*
* <p>
* Note that even if this method returns true, the user can still skip aut
*
* @param auth
* Always non-null.
* If the underlying transport had already performed authentication, this object is something other than
* {@link Hudson#ANONYMOUS}.
*/
protected boolean shouldPerformAuthentication(Authentication auth) {
return auth==Hudson.ANONYMOUS;
}
/**
* Returns the identity of the client as determined at the CLI transport level.
*
* <p>
* When the CLI connection to the server is tunneled over HTTP, that HTTP connection
* can authenticate the client, just like any other HTTP connections to the server
* can authenticate the client. This method returns that information, if one is available.
* By generalizing it, this method returns the identity obtained at the transport-level authentication.
*
* <p>
* For example, imagine if the current {@link SecurityRealm} is doing Kerberos authentication,
* then this method can return a valid identity of the client.
*
* <p>
* If the transport doesn't do authentication, this method returns {@link Hudson#ANONYMOUS}.
*/
public Authentication getTransportAuthentication() {
Authentication a = channel.getProperty(TRANSPORT_AUTHENTICATION);
if (a==null) a = Hudson.ANONYMOUS;
return a;
}
/**
* Executes the command, and return the exit code.
*
* @return
* 0 to indicate a success, otherwise an error code.
* @throws AbortException
* If the processing should be aborted. Hudson will report the error message
* without stack trace, and then exits this command.
* @throws Exception
* All the other exceptions cause the stack trace to be dumped, and then
* the command exits with an error code.
*/
protected abstract int run() throws Exception;
protected void printUsage(PrintStream stderr, CmdLineParser p) {
stderr.println("java -jar hudson-cli.jar "+getName()+" args...");
printUsageSummary(stderr);
p.printUsage(stderr);
}
/**
* Called while producing usage. This is a good method to override
* to render the general description of the command that goes beyond
* a single-line summary.
*/
protected void printUsageSummary(PrintStream stderr) {
stderr.println(getShortDescription());
}
/**
* Convenience method for subtypes to obtain the system property of the client.
*/
protected String getClientSystemProperty(String name) throws IOException, InterruptedException {
return channel.call(new GetSystemProperty(name));
}
private static final class GetSystemProperty implements Callable<String, IOException> {
private final String name;
private GetSystemProperty(String name) {
this.name = name;
}
public String call() throws IOException {
return System.getProperty(name);
}
private static final long serialVersionUID = 1L;
}
/**
* Convenience method for subtypes to obtain environment variables of the client.
*/
protected String getClientEnvironmentVariable(String name) throws IOException, InterruptedException {
return channel.call(new GetEnvironmentVariable(name));
}
private static final class GetEnvironmentVariable implements Callable<String, IOException> {
private final String name;
private GetEnvironmentVariable(String name) {
this.name = name;
}
public String call() throws IOException {
return System.getenv(name);
}
private static final long serialVersionUID = 1L;
}
/**
* Creates a clone to be used to execute a command.
*/
protected CLICommand createClone() {
try {
return getClass().newInstance();
} catch (IllegalAccessException e) {
throw new AssertionError(e);
} catch (InstantiationException e) {
throw new AssertionError(e);
}
}
/**
* Auto-discovers {@link OptionHandler}s and add them to the given command line parser.
*/
protected void registerOptionHandlers() {
try {
for (Class c : Index.list(OptionHandlerExtension.class,Hudson.getInstance().pluginManager.uberClassLoader,Class.class)) {
Type t = Types.getBaseClass(c, OptionHandler.class);
CmdLineParser.registerHandler(Types.erasure(Types.getTypeArgument(t,0)), c);
}
} catch (IOException e) {
throw new Error(e);
}
}
/**
* Returns all the registered {@link CLICommand}s.
*/
public static ExtensionList<CLICommand> all() {
return Hudson.getInstance().getExtensionList(CLICommand.class);
}
/**
* Obtains a copy of the command for invocation.
*/
public static CLICommand clone(String name) {
for (CLICommand cmd : all())
if(name.equals(cmd.getName()))
return cmd.createClone();
return null;
}
private static final Logger LOGGER = Logger.getLogger(CLICommand.class.getName());
/**
* Key for {@link Channel#getProperty(Object)} that links to the {@link Authentication} object
* which captures the identity of the client given by the transport layer.
*/
public static final ChannelProperty<Authentication> TRANSPORT_AUTHENTICATION = new ChannelProperty<Authentication>(Authentication.class,"transportAuthentication");
private static final ThreadLocal<CLICommand> CURRENT_COMMAND = new ThreadLocal<CLICommand>();
/*package*/ static CLICommand setCurrent(CLICommand cmd) {
CLICommand old = getCurrent();
CURRENT_COMMAND.set(cmd);
return old;
}
/**
* If the calling thread is in the middle of executing a CLI command, return it. Otherwise null.
*/
public static CLICommand getCurrent() {
return CURRENT_COMMAND.get();
}
}