org.springframework.web.reactive.result.method.SyncInvocableHandlerMethod Maven / Gradle / Ivy
/*
* Copyright 2002-2018 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.
* 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.springframework.web.reactive.result.method;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;
import reactor.core.publisher.MonoProcessor;
import org.springframework.core.DefaultParameterNameDiscoverer;
import org.springframework.core.ParameterNameDiscoverer;
import org.springframework.lang.Nullable;
import org.springframework.web.method.HandlerMethod;
import org.springframework.web.reactive.BindingContext;
import org.springframework.web.reactive.HandlerResult;
import org.springframework.web.server.ServerErrorException;
import org.springframework.web.server.ServerWebExchange;
/**
* Extension of {@link HandlerMethod} that invokes the underlying method via
* {@link InvocableHandlerMethod} but uses sync argument resolvers only and
* thus can return directly a {@link HandlerResult} with no async wrappers.
*
* @author Rossen Stoyanchev
* @since 5.0
*/
public class SyncInvocableHandlerMethod extends HandlerMethod {
private final InvocableHandlerMethod delegate;
public SyncInvocableHandlerMethod(HandlerMethod handlerMethod) {
super(handlerMethod);
this.delegate = new InvocableHandlerMethod(handlerMethod);
}
public SyncInvocableHandlerMethod(Object bean, Method method) {
super(bean, method);
this.delegate = new InvocableHandlerMethod(bean, method);
}
/**
* Configure the argument resolvers to use to use for resolving method
* argument values against a {@code ServerWebExchange}.
*/
public void setArgumentResolvers(List resolvers) {
this.delegate.setArgumentResolvers(new ArrayList<>(resolvers));
}
/**
* Return the configured argument resolvers.
*/
public List getResolvers() {
return this.delegate.getResolvers().stream()
.map(resolver -> (SyncHandlerMethodArgumentResolver) resolver)
.collect(Collectors.toList());
}
/**
* Set the ParameterNameDiscoverer for resolving parameter names when needed
* (e.g. default request attribute name).
* Default is a {@link DefaultParameterNameDiscoverer}.
*/
public void setParameterNameDiscoverer(ParameterNameDiscoverer nameDiscoverer) {
this.delegate.setParameterNameDiscoverer(nameDiscoverer);
}
/**
* Return the configured parameter name discoverer.
*/
public ParameterNameDiscoverer getParameterNameDiscoverer() {
return this.delegate.getParameterNameDiscoverer();
}
/**
* Invoke the method for the given exchange.
* @param exchange the current exchange
* @param bindingContext the binding context to use
* @param providedArgs optional list of argument values to match by type
* @return Mono with a {@link HandlerResult}.
* @throws ServerErrorException if method argument resolution or method invocation fails
*/
@Nullable
public HandlerResult invokeForHandlerResult(ServerWebExchange exchange,
BindingContext bindingContext, Object... providedArgs) {
MonoProcessor processor = MonoProcessor.create();
this.delegate.invoke(exchange, bindingContext, providedArgs).subscribeWith(processor);
if (processor.isTerminated()) {
Throwable ex = processor.getError();
if (ex != null) {
throw (ex instanceof ServerErrorException ? (ServerErrorException) ex :
new ServerErrorException("Failed to invoke: " + getShortLogMessage(), getMethod(), ex));
}
return processor.peek();
}
else {
// Should never happen...
throw new IllegalStateException(
"SyncInvocableHandlerMethod should have completed synchronously.");
}
}
}