org.springframework.http.server.reactive.AbstractServerHttpResponse 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.http.server.reactive;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.atomic.AtomicReference;
import java.util.function.Supplier;
import java.util.stream.Collectors;
import org.apache.commons.logging.Log;
import org.reactivestreams.Publisher;
import reactor.core.publisher.Flux;
import reactor.core.publisher.Mono;
import org.springframework.core.io.buffer.DataBuffer;
import org.springframework.core.io.buffer.DataBufferFactory;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpLogging;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseCookie;
import org.springframework.lang.Nullable;
import org.springframework.util.Assert;
import org.springframework.util.CollectionUtils;
import org.springframework.util.LinkedMultiValueMap;
import org.springframework.util.MultiValueMap;
/**
* Base class for {@link ServerHttpResponse} implementations.
*
* @author Rossen Stoyanchev
* @author Juergen Hoeller
* @author Sebastien Deleuze
* @author Brian Clozel
* @since 5.0
*/
public abstract class AbstractServerHttpResponse implements ServerHttpResponse {
/**
* COMMITTING -> COMMITTED is the period after doCommit is called but before
* the response status and headers have been applied to the underlying
* response during which time pre-commit actions can still make changes to
* the response status and headers.
*/
private enum State {NEW, COMMITTING, COMMITTED}
protected final Log logger = HttpLogging.forLogName(getClass());
private final DataBufferFactory dataBufferFactory;
@Nullable
private Integer statusCode;
private final HttpHeaders headers;
private final MultiValueMap cookies;
private final AtomicReference state = new AtomicReference<>(State.NEW);
private final List>> commitActions = new ArrayList<>(4);
public AbstractServerHttpResponse(DataBufferFactory dataBufferFactory) {
this(dataBufferFactory, new HttpHeaders());
}
public AbstractServerHttpResponse(DataBufferFactory dataBufferFactory, HttpHeaders headers) {
Assert.notNull(dataBufferFactory, "DataBufferFactory must not be null");
Assert.notNull(headers, "HttpHeaders must not be null");
this.dataBufferFactory = dataBufferFactory;
this.headers = headers;
this.cookies = new LinkedMultiValueMap<>();
}
@Override
public final DataBufferFactory bufferFactory() {
return this.dataBufferFactory;
}
@Override
public boolean setStatusCode(@Nullable HttpStatus status) {
if (this.state.get() == State.COMMITTED) {
return false;
}
else {
this.statusCode = (status != null ? status.value() : null);
return true;
}
}
@Override
@Nullable
public HttpStatus getStatusCode() {
return this.statusCode != null ? HttpStatus.resolve(this.statusCode) : null;
}
/**
* Set the HTTP status code of the response.
* @param statusCode the HTTP status as an integer value
* @since 5.0.1
*/
public void setStatusCodeValue(@Nullable Integer statusCode) {
this.statusCode = statusCode;
}
/**
* Return the HTTP status code of the response.
* @return the HTTP status as an integer value
* @since 5.0.1
*/
@Nullable
public Integer getStatusCodeValue() {
return this.statusCode;
}
@Override
public HttpHeaders getHeaders() {
return (this.state.get() == State.COMMITTED ?
HttpHeaders.readOnlyHttpHeaders(this.headers) : this.headers);
}
@Override
public MultiValueMap getCookies() {
return (this.state.get() == State.COMMITTED ?
CollectionUtils.unmodifiableMultiValueMap(this.cookies) : this.cookies);
}
@Override
public void addCookie(ResponseCookie cookie) {
Assert.notNull(cookie, "ResponseCookie must not be null");
if (this.state.get() == State.COMMITTED) {
throw new IllegalStateException("Can't add the cookie " + cookie +
"because the HTTP response has already been committed");
}
else {
getCookies().add(cookie.getName(), cookie);
}
}
/**
* Return the underlying server response.
* Note: This is exposed mainly for internal framework
* use such as WebSocket upgrades in the spring-webflux module.
*/
public abstract T getNativeResponse();
@Override
public void beforeCommit(Supplier> action) {
this.commitActions.add(action);
}
@Override
public boolean isCommitted() {
return this.state.get() != State.NEW;
}
@Override
public final Mono writeWith(Publisher body) {
return new ChannelSendOperator<>(body,
writePublisher -> doCommit(() -> writeWithInternal(writePublisher)))
.doOnError(t -> removeContentLength());
}
@Override
public final Mono writeAndFlushWith(Publisher> body) {
return new ChannelSendOperator<>(body,
writePublisher -> doCommit(() -> writeAndFlushWithInternal(writePublisher)))
.doOnError(t -> removeContentLength());
}
private void removeContentLength() {
if (!this.isCommitted()) {
this.getHeaders().remove(HttpHeaders.CONTENT_LENGTH);
}
}
@Override
public Mono setComplete() {
return !isCommitted() ? doCommit(null) : Mono.empty();
}
/**
* A variant of {@link #doCommit(Supplier)} for a response without no body.
* @return a completion publisher
*/
protected Mono doCommit() {
return doCommit(null);
}
/**
* Apply {@link #beforeCommit(Supplier) beforeCommit} actions, apply the
* response status and headers/cookies, and write the response body.
* @param writeAction the action to write the response body (may be {@code null})
* @return a completion publisher
*/
protected Mono doCommit(@Nullable Supplier> writeAction) {
if (!this.state.compareAndSet(State.NEW, State.COMMITTING)) {
return Mono.empty();
}
this.commitActions.add(() ->
Mono.fromRunnable(() -> {
applyStatusCode();
applyHeaders();
applyCookies();
this.state.set(State.COMMITTED);
}));
if (writeAction != null) {
this.commitActions.add(writeAction);
}
List> actions = this.commitActions.stream()
.map(Supplier::get).collect(Collectors.toList());
return Flux.concat(actions).then();
}
/**
* Write to the underlying the response.
* @param body the publisher to write with
*/
protected abstract Mono writeWithInternal(Publisher body);
/**
* Write to the underlying the response, and flush after each {@code Publisher}.
* @param body the publisher to write and flush with
*/
protected abstract Mono writeAndFlushWithInternal(Publisher> body);
/**
* Write the status code to the underlying response.
* This method is called once only.
*/
protected abstract void applyStatusCode();
/**
* Apply header changes from {@link #getHeaders()} to the underlying response.
* This method is called once only.
*/
protected abstract void applyHeaders();
/**
* Add cookies from {@link #getHeaders()} to the underlying response.
* This method is called once only.
*/
protected abstract void applyCookies();
}