/*
* 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.jclouds.rest.internal;
import static com.google.common.base.Objects.equal;
import static com.google.common.base.Objects.toStringHelper;
import static com.google.common.base.Preconditions.checkState;
import static com.google.common.base.Throwables.propagate;
import static com.google.common.util.concurrent.Futures.transform;
import static com.google.common.util.concurrent.Futures.withFallback;
import static java.util.concurrent.TimeUnit.NANOSECONDS;
import static org.jclouds.Constants.PROPERTY_USER_THREADS;
import java.util.concurrent.Callable;
import java.util.concurrent.TimeUnit;
import javax.annotation.Resource;
import javax.inject.Inject;
import javax.inject.Named;
import org.jclouds.http.HttpCommand;
import org.jclouds.http.HttpCommandExecutorService;
import org.jclouds.http.HttpRequest;
import org.jclouds.http.HttpResponse;
import org.jclouds.logging.Logger;
import org.jclouds.reflect.Invocation;
import org.jclouds.rest.InvocationContext;
import org.jclouds.rest.config.InvocationConfig;
import com.google.common.annotations.VisibleForTesting;
import com.google.common.base.Function;
import com.google.common.base.Objects;
import com.google.common.base.Optional;
import com.google.common.reflect.Invokable;
import com.google.common.util.concurrent.ListenableFuture;
import com.google.common.util.concurrent.ListeningExecutorService;
import com.google.common.util.concurrent.TimeLimiter;
import com.google.common.util.concurrent.UncheckedTimeoutException;
/**
* @author Adrian Cole
* @deprecated will be replaced in jclouds 1.7 with {@link InvokeHttpMethod}, as async interfaces are no longer supported.
*/
@Deprecated
public class InvokeSyncToAsyncHttpMethod implements Function<Invocation, Object> {
@Resource
private Logger logger = Logger.NULL;
private final Function<Invocation, Invocation> sync2async;
private final Function<Invocation, HttpRequest> annotationProcessor;
private final HttpCommandExecutorService http;
private final ListeningExecutorService userExecutor;
private final TimeLimiter timeLimiter;
private final Function<HttpRequest, Function<HttpResponse, ?>> transformerForRequest;
private final InvocationConfig config;
@Inject
@VisibleForTesting
InvokeSyncToAsyncHttpMethod(Function<Invocation, Invocation> sync2async, Function<Invocation, HttpRequest> annotationProcessor,
HttpCommandExecutorService http, Function<HttpRequest, Function<HttpResponse, ?>> transformerForRequest,
TimeLimiter timeLimiter, InvocationConfig config,
@Named(PROPERTY_USER_THREADS) ListeningExecutorService userExecutor) {
this.sync2async = sync2async;
this.annotationProcessor = annotationProcessor;
this.http = http;
this.userExecutor = userExecutor;
this.timeLimiter = timeLimiter;
this.transformerForRequest = transformerForRequest;
this.config = config;
}
@Override
public Object apply(Invocation in) {
if (isFuture(in.getInvokable())) {
return submit(in);
}
Invocation async = toAsync(in);
Optional<Long> timeoutNanos = config.getTimeoutNanos(async);
if (timeoutNanos.isPresent()) {
return invokeWithTimeout(async, timeoutNanos.get());
}
return invoke(async);
}
/**
* submits the {@linkplain HttpCommand} associated with {@code invocation},
* {@link #getTransformer(String, HttpCommand) parses its response}, and
* applies a {@link #getFallback(String, Invocation, HttpCommand) fallback}
* if a {@code Throwable} is encountered. Parsing and Fallback occur on the
* {@code userExecutor} thread.
*/
public ListenableFuture<?> submit(Invocation invocation) {
String commandName = config.getCommandName(invocation);
HttpCommand command = toCommand(commandName, invocation);
Function<HttpResponse, ?> transformer = getTransformer(commandName, command);
org.jclouds.Fallback<?> fallback = getFallback(commandName, invocation, command);
logger.debug(">> submitting %s", commandName);
return withFallback(transform(http.submit(command), transformer, userExecutor), fallback);
}
/**
* invokes the {@linkplain HttpCommand} associated with {@code invocation},
* {@link #getTransformer(String, HttpCommand) parses its response}, and
* applies a {@link #getFallback(String, Invocation, HttpCommand) fallback}
* if a {@code Throwable} is encountered.
*/
public Object invoke(Invocation invocation) {
String commandName = config.getCommandName(invocation);
HttpCommand command = toCommand(commandName, invocation);
Function<HttpResponse, ?> transformer = getTransformer(commandName, command);
org.jclouds.Fallback<?> fallback = getFallback(commandName, invocation, command);
logger.debug(">> invoking %s", commandName);
try {
return transformer.apply(http.invoke(command));
} catch (Throwable t) {
try {
return fallback.createOrPropagate(t);
} catch (Exception e) {
throw propagate(e);
}
}
}
/**
* calls {@link #invoke(Invocation)}, timing out after the specified time
* limit. If the target method call finished before the limit is reached, the
* return value or exception is propagated to the caller exactly as-is. If,
* on the other hand, the time limit is reached, we attempt to abort the call
* to the target, and throw an {@link UncheckedTimeoutException} to the
* caller.
*
* @param invocation
* the Invocation to invoke via {@link #invoke(Invocation)}
* @param limitNanos
* with timeoutUnit, the maximum length of time to wait in
* nanoseconds
* @throws InterruptedException
* if our thread is interrupted during execution
* @throws UncheckedTimeoutException
* if the time limit is reached
* @see TimeLimiter#callWithTimeout(Callable, long, TimeUnit, boolean)
*/
public Object invokeWithTimeout(final Invocation invocation, final long limitNanos) {
String commandName = config.getCommandName(invocation);
HttpCommand command = toCommand(commandName, invocation);
org.jclouds.Fallback<?> fallback = getFallback(commandName, invocation, command);
logger.debug(">> blocking on %s for %s", invocation, limitNanos);
try {
return timeLimiter
.callWithTimeout(new InvokeAndTransform(commandName, command), limitNanos, NANOSECONDS, true);
} catch (Throwable t) {
try {
return fallback.createOrPropagate(t);
} catch (Exception e) {
throw propagate(e);
}
}
}
private org.jclouds.Fallback<?> getFallback(String commandName, Invocation invocation, HttpCommand command) {
HttpRequest request = command.getCurrentRequest();
org.jclouds.Fallback<?> fallback = config.getFallback(invocation);
if (fallback instanceof InvocationContext)
InvocationContext.class.cast(fallback).setContext(request);
logger.trace("<< exceptions from %s are parsed by %s", commandName, fallback.getClass().getSimpleName());
return fallback;
}
@VisibleForTesting
final class InvokeAndTransform implements Callable<Object> {
private final String commandName;
private final HttpCommand command;
private final Function<HttpResponse, ?> transformer;
InvokeAndTransform(String commandName, HttpCommand command) {
this.commandName = commandName;
this.command = command;
this.transformer = getTransformer(commandName, command);
}
@Override
public Object call() throws Exception {
return transformer.apply(http.invoke(command));
}
@Override
public int hashCode() {
return Objects.hashCode(commandName, command, transformer);
}
@Override
public boolean equals(Object obj) {
if (this == obj)
return true;
if (obj == null || getClass() != obj.getClass())
return false;
InvokeAndTransform that = InvokeAndTransform.class.cast(obj);
return equal(this.commandName, that.commandName) && equal(this.command, that.command)
&& equal(this.transformer, that.transformer);
}
@Override
public String toString() {
return toStringHelper(this).add("commandName", commandName).add("command", command)
.add("transformer", transformer).toString();
}
}
/**
* looks up the corresponding {@code Invocation} that returns a
* {@code Future}. Only Invokables that return {@code Futures} are annotated
* in a way that can be parsed into an {@linkplain HttpRequest}.
*/
private Invocation toAsync(Invocation in) {
Invocation async = sync2async.apply(in);
checkState(isFuture(async.getInvokable()), "not a future: %s", async);
return async;
}
private HttpCommand toCommand(String commandName, Invocation invocation) {
logger.trace(">> converting %s", commandName);
HttpRequest request = annotationProcessor.apply(invocation);
logger.trace("<< converted %s to %s", commandName, request.getRequestLine());
return new HttpCommand(request);
}
private Function<HttpResponse, ?> getTransformer(String commandName, HttpCommand command) {
HttpRequest request = command.getCurrentRequest();
Function<HttpResponse, ?> transformer = transformerForRequest.apply(request);
logger.trace("<< response from %s is parsed by %s", commandName, transformer.getClass().getSimpleName());
return transformer;
}
private boolean isFuture(Invokable<?, ?> in) {
return in.getReturnType().getRawType().equals(ListenableFuture.class);
}
@Override
public boolean equals(Object o) {
if (this == o)
return true;
if (o == null || getClass() != o.getClass())
return false;
InvokeSyncToAsyncHttpMethod that = InvokeSyncToAsyncHttpMethod.class.cast(o);
return equal(this.annotationProcessor, that.annotationProcessor);
}
@Override
public int hashCode() {
return Objects.hashCode(annotationProcessor);
}
@Override
public String toString() {
return Objects.toStringHelper("").omitNullValues().add("annotationParser", annotationProcessor).toString();
}
}