org.springframework.web.servlet.function.ServerResponse Maven / Gradle / Ivy
/*
* Copyright 2002-2019 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
*
* https://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.servlet.function;
import java.io.IOException;
import java.net.URI;
import java.time.Duration;
import java.time.Instant;
import java.time.ZonedDateTime;
import java.util.Collection;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.CompletionStage;
import java.util.function.BiFunction;
import java.util.function.Consumer;
import javax.servlet.ServletException;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.reactivestreams.Publisher;
import org.springframework.core.ParameterizedTypeReference;
import org.springframework.core.ReactiveAdapterRegistry;
import org.springframework.http.CacheControl;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpMethod;
import org.springframework.http.HttpStatus;
import org.springframework.http.MediaType;
import org.springframework.http.converter.HttpMessageConverter;
import org.springframework.lang.Nullable;
import org.springframework.util.MultiValueMap;
import org.springframework.web.servlet.ModelAndView;
/**
* Represents a typed server-side HTTP response, as returned
* by a {@linkplain HandlerFunction handler function} or
* {@linkplain HandlerFilterFunction filter function}.
*
* @author Arjen Poutsma
* @since 5.2
*/
public interface ServerResponse {
/**
* Return the status code of this response.
* @return the status as an HttpStatus enum value
* @throws IllegalArgumentException in case of an unknown HTTP status code
* @see HttpStatus#valueOf(int)
*/
HttpStatus statusCode();
/**
* Return the (potentially non-standard) status code of this response.
* @return the status as an integer
* @see #statusCode()
* @see HttpStatus#valueOf(int)
*/
int rawStatusCode();
/**
* Return the headers of this response.
*/
HttpHeaders headers();
/**
* Return the cookies of this response.
*/
MultiValueMap cookies();
/**
* Write this response to the given servlet response.
* @param request the current request
* @param response the response to write to
* @param context the context to use when writing
* @return a {@code ModelAndView} to render, or {@code null} if handled directly
*/
@Nullable
ModelAndView writeTo(HttpServletRequest request, HttpServletResponse response, Context context)
throws ServletException, IOException;
// Static methods
/**
* Create a builder with the status code and headers of the given response.
* @param other the response to copy the status and headers from
* @return the created builder
*/
static BodyBuilder from(ServerResponse other) {
return new DefaultServerResponseBuilder(other);
}
/**
* Create a builder with the given HTTP status.
* @param status the response status
* @return the created builder
*/
static BodyBuilder status(HttpStatus status) {
return new DefaultServerResponseBuilder(status);
}
/**
* Create a builder with the given HTTP status.
* @param status the response status
* @return the created builder
*/
static BodyBuilder status(int status) {
return new DefaultServerResponseBuilder(status);
}
/**
* Create a builder with the status set to {@linkplain HttpStatus#OK 200 OK}.
* @return the created builder
*/
static BodyBuilder ok() {
return status(HttpStatus.OK);
}
/**
* Create a builder with a {@linkplain HttpStatus#CREATED 201 Created} status
* and a location header set to the given URI.
* @param location the location URI
* @return the created builder
*/
static BodyBuilder created(URI location) {
BodyBuilder builder = status(HttpStatus.CREATED);
return builder.location(location);
}
/**
* Create a builder with a {@linkplain HttpStatus#ACCEPTED 202 Accepted} status.
* @return the created builder
*/
static BodyBuilder accepted() {
return status(HttpStatus.ACCEPTED);
}
/**
* Create a builder with a {@linkplain HttpStatus#NO_CONTENT 204 No Content} status.
* @return the created builder
*/
static HeadersBuilder noContent() {
return status(HttpStatus.NO_CONTENT);
}
/**
* Create a builder with a {@linkplain HttpStatus#SEE_OTHER 303 See Other}
* status and a location header set to the given URI.
* @param location the location URI
* @return the created builder
*/
static BodyBuilder seeOther(URI location) {
BodyBuilder builder = status(HttpStatus.SEE_OTHER);
return builder.location(location);
}
/**
* Create a builder with a {@linkplain HttpStatus#TEMPORARY_REDIRECT 307 Temporary Redirect}
* status and a location header set to the given URI.
* @param location the location URI
* @return the created builder
*/
static BodyBuilder temporaryRedirect(URI location) {
BodyBuilder builder = status(HttpStatus.TEMPORARY_REDIRECT);
return builder.location(location);
}
/**
* Create a builder with a {@linkplain HttpStatus#PERMANENT_REDIRECT 308 Permanent Redirect}
* status and a location header set to the given URI.
* @param location the location URI
* @return the created builder
*/
static BodyBuilder permanentRedirect(URI location) {
BodyBuilder builder = status(HttpStatus.PERMANENT_REDIRECT);
return builder.location(location);
}
/**
* Create a builder with a {@linkplain HttpStatus#BAD_REQUEST 400 Bad Request} status.
* @return the created builder
*/
static BodyBuilder badRequest() {
return status(HttpStatus.BAD_REQUEST);
}
/**
* Create a builder with a {@linkplain HttpStatus#NOT_FOUND 404 Not Found} status.
* @return the created builder
*/
static HeadersBuilder notFound() {
return status(HttpStatus.NOT_FOUND);
}
/**
* Create a builder with a
* {@linkplain HttpStatus#UNPROCESSABLE_ENTITY 422 Unprocessable Entity} status.
* @return the created builder
*/
static BodyBuilder unprocessableEntity() {
return status(HttpStatus.UNPROCESSABLE_ENTITY);
}
/**
* Create a (built) response with the given asynchronous response.
* Parameter {@code asyncResponse} can be a
* {@link CompletableFuture CompletableFuture<ServerResponse>} or
* {@link Publisher Publisher<ServerResponse>} (or any
* asynchronous producer of a single {@code ServerResponse} that can be
* adapted via the {@link ReactiveAdapterRegistry}).
*
* This method can be used to set the response status code, headers, and
* body based on an asynchronous result. If only the body is asynchronous,
* {@link BodyBuilder#body(Object)} can be used instead.
* @param asyncResponse a {@code CompletableFuture} or
* {@code Publisher}
* @return the asynchronous response
* @since 5.3
*/
static ServerResponse async(Object asyncResponse) {
return DefaultAsyncServerResponse.create(asyncResponse, null);
}
/**
* Create a (built) response with the given asynchronous response.
* Parameter {@code asyncResponse} can be a
* {@link CompletableFuture CompletableFuture<ServerResponse>} or
* {@link Publisher Publisher<ServerResponse>} (or any
* asynchronous producer of a single {@code ServerResponse} that can be
* adapted via the {@link ReactiveAdapterRegistry}).
*
* This method can be used to set the response status code, headers, and
* body based on an asynchronous result. If only the body is asynchronous,
* {@link BodyBuilder#body(Object)} can be used instead.
* @param asyncResponse a {@code CompletableFuture} or
* {@code Publisher}
* @param timeout maximum time period to wait for before timing out
* @return the asynchronous response
* @since 5.3.2
*/
static ServerResponse async(Object asyncResponse, Duration timeout) {
return DefaultAsyncServerResponse.create(asyncResponse, timeout);
}
/**
* Create a server-sent event response. The {@link SseBuilder} provided to
* {@code consumer} can be used to build and send events.
*
* For example:
*
* public ServerResponse handleSse(ServerRequest request) {
* return ServerResponse.sse(sse -> sse.send("Hello World!"));
* }
*
*
* or, to set both the id and event type:
*
* public ServerResponse handleSse(ServerRequest request) {
* return ServerResponse.sse(sse -> sse
* .id("42)
* .event("event")
* .send("Hello World!"));
* }
*
* @param consumer consumer that will be provided with an event builder
* @return the server-side event response
* @since 5.3.2
* @see Server-Sent Events
*/
static ServerResponse sse(Consumer consumer) {
return SseServerResponse.create(consumer, null);
}
/**
* Create a server-sent event response. The {@link SseBuilder} provided to
* {@code consumer} can be used to build and send events.
*
* For example:
*
* public ServerResponse handleSse(ServerRequest request) {
* return ServerResponse.sse(sse -> sse.send("Hello World!"));
* }
*
*
* or, to set both the id and event type:
*
* public ServerResponse handleSse(ServerRequest request) {
* return ServerResponse.sse(sse -> sse
* .id("42)
* .event("event")
* .send("Hello World!"));
* }
*
* @param consumer consumer that will be provided with an event builder
* @param timeout maximum time period to wait before timing out
* @return the server-side event response
* @since 5.3.2
* @see Server-Sent Events
*/
static ServerResponse sse(Consumer consumer, Duration timeout) {
return SseServerResponse.create(consumer, timeout);
}
/**
* Defines a builder that adds headers to the response.
* @param the builder subclass
*/
interface HeadersBuilder> {
/**
* Add the given header value(s) under the given name.
* @param headerName the header name
* @param headerValues the header value(s)
* @return this builder
* @see HttpHeaders#add(String, String)
*/
B header(String headerName, String... headerValues);
/**
* Manipulate this response's headers with the given consumer. The
* headers provided to the consumer are "live", so that the consumer can be used to
* {@linkplain HttpHeaders#set(String, String) overwrite} existing header values,
* {@linkplain HttpHeaders#remove(Object) remove} values, or use any of the other
* {@link HttpHeaders} methods.
* @param headersConsumer a function that consumes the {@code HttpHeaders}
* @return this builder
*/
B headers(Consumer headersConsumer);
/**
* Add the given cookie to the response.
* @param cookie the cookie to add
* @return this builder
*/
B cookie(Cookie cookie);
/**
* Manipulate this response's cookies with the given consumer. The
* cookies provided to the consumer are "live", so that the consumer can be used to
* {@linkplain MultiValueMap#set(Object, Object) overwrite} existing cookies,
* {@linkplain MultiValueMap#remove(Object) remove} cookies, or use any of the other
* {@link MultiValueMap} methods.
* @param cookiesConsumer a function that consumes the cookies
* @return this builder
*/
B cookies(Consumer> cookiesConsumer);
/**
* Set the set of allowed {@link HttpMethod HTTP methods}, as specified
* by the {@code Allow} header.
*
* @param allowedMethods the allowed methods
* @return this builder
* @see HttpHeaders#setAllow(Set)
*/
B allow(HttpMethod... allowedMethods);
/**
* Set the set of allowed {@link HttpMethod HTTP methods}, as specified
* by the {@code Allow} header.
* @param allowedMethods the allowed methods
* @return this builder
* @see HttpHeaders#setAllow(Set)
*/
B allow(Set allowedMethods);
/**
* Set the entity tag of the body, as specified by the {@code ETag} header.
* @param eTag the new entity tag
* @return this builder
* @see HttpHeaders#setETag(String)
*/
B eTag(String eTag);
/**
* Set the time the resource was last changed, as specified by the
* {@code Last-Modified} header.
* @param lastModified the last modified date
* @return this builder
* @see HttpHeaders#setLastModified(long)
*/
B lastModified(ZonedDateTime lastModified);
/**
* Set the time the resource was last changed, as specified by the
* {@code Last-Modified} header.
* @param lastModified the last modified date
* @return this builder
* @see HttpHeaders#setLastModified(long)
*/
B lastModified(Instant lastModified);
/**
* Set the location of a resource, as specified by the {@code Location} header.
* @param location the location
* @return this builder
* @see HttpHeaders#setLocation(URI)
*/
B location(URI location);
/**
* Set the caching directives for the resource, as specified by the HTTP 1.1
* {@code Cache-Control} header.
* A {@code CacheControl} instance can be built like
* {@code CacheControl.maxAge(3600).cachePublic().noTransform()}.
* @param cacheControl a builder for cache-related HTTP response headers
* @return this builder
* @see RFC-7234 Section 5.2
*/
B cacheControl(CacheControl cacheControl);
/**
* Configure one or more request header names (e.g. "Accept-Language") to
* add to the "Vary" response header to inform clients that the response is
* subject to content negotiation and variances based on the value of the
* given request headers. The configured request header names are added only
* if not already present in the response "Vary" header.
* @param requestHeaders request header names
* @return this builder
*/
B varyBy(String... requestHeaders);
/**
* Build the response entity with no body.
*/
ServerResponse build();
/**
* Build the response entity with a custom write function.
* @param writeFunction the function used to write to the {@link HttpServletResponse}
*/
ServerResponse build(BiFunction writeFunction);
}
/**
* Defines a builder that adds a body to the response.
*/
interface BodyBuilder extends HeadersBuilder {
/**
* Set the length of the body in bytes, as specified by the
* {@code Content-Length} header.
* @param contentLength the content length
* @return this builder
* @see HttpHeaders#setContentLength(long)
*/
BodyBuilder contentLength(long contentLength);
/**
* Set the {@linkplain MediaType media type} of the body, as specified by the
* {@code Content-Type} header.
* @param contentType the content type
* @return this builder
* @see HttpHeaders#setContentType(MediaType)
*/
BodyBuilder contentType(MediaType contentType);
/**
* Set the body of the response to the given {@code Object} and return
* it.
*
* Asynchronous response bodies are supported by providing a
* {@link CompletionStage} or {@link Publisher} as body (or any
* asynchronous producer of a single entity that can be adapted via the
* {@link ReactiveAdapterRegistry}).
* @param body the body of the response
* @return the built response
*/
ServerResponse body(Object body);
/**
* Set the body of the response to the given {@code Object} and return it. The parameter
* {@code bodyType} is used to capture the generic type.
*
* @param body the body of the response
* @param bodyType the type of the body, used to capture the generic type
* @return the built response
*/
ServerResponse body(T body, ParameterizedTypeReference bodyType);
/**
* Render the template with the given {@code name} using the given {@code modelAttributes}.
* The model attributes are mapped under a
* {@linkplain org.springframework.core.Conventions#getVariableName generated name}.
* Note: Empty {@link Collection Collections} are not added to
* the model when using this method because we cannot correctly determine
* the true convention name.
* @param name the name of the template to be rendered
* @param modelAttributes the modelAttributes used to render the template
* @return the built response
*/
ServerResponse render(String name, Object... modelAttributes);
/**
* Render the template with the given {@code name} using the given {@code model}.
* @param name the name of the template to be rendered
* @param model the model used to render the template
* @return the built response
*/
ServerResponse render(String name, Map model);
}
/**
* Defines a builder for a body that sends server-sent events.
*
* @since 5.3.2
*/
interface SseBuilder {
/**
* Sends the given object as a server-sent event.
* Strings will be sent as UTF-8 encoded bytes, and other objects will
* be converted into JSON using
* {@linkplain HttpMessageConverter message converters}.
*
* This convenience method has the same effect as
* {@link #data(Object)}.
* @param object the object to send
* @throws IOException in case of I/O errors
*/
void send(Object object) throws IOException;
/**
* Add an SSE "id" line.
* @param id the event identifier
* @return this builder
*/
SseBuilder id(String id);
/**
* Add an SSE "event" line.
* @param eventName the event name
* @return this builder
*/
SseBuilder event(String eventName);
/**
* Add an SSE "retry" line.
* @param duration the duration to convert into millis
* @return this builder
*/
SseBuilder retry(Duration duration);
/**
* Add an SSE comment.
* @param comment the comment
* @return this builder
*/
SseBuilder comment(String comment);
/**
* Add an SSE "data" line for the given object and sends the built
* server-sent event to the client.
* Strings will be sent as UTF-8 encoded bytes, and other objects will
* be converted into JSON using
* {@linkplain HttpMessageConverter message converters}.
* @param object the object to send as data
* @throws IOException in case of I/O errors
*/
void data(Object object) throws IOException;
/**
* Completes the event stream with the given error.
*
*
The throwable is dispatched back into Spring MVC, and passed to
* its exception handling mechanism. Since the response has
* been committed by this point, the response status can not change.
* @param t the throwable to dispatch
*/
void error(Throwable t);
/**
* Completes the event stream.
*/
void complete();
/**
* Register a callback to be invoked when an SSE request times
* out.
* @param onTimeout the callback to invoke on timeout
* @return this builder
*/
SseBuilder onTimeout(Runnable onTimeout);
/**
* Register a callback to be invoked when an error occurs during SSE
* processing.
* @param onError the callback to invoke on error
* @return this builder
*/
SseBuilder onError(Consumer onError);
/**
* Register a callback to be invoked when the SSE request completes.
* @param onCompletion the callback to invoked on completion
* @return this builder
*/
SseBuilder onComplete(Runnable onCompletion);
}
/**
* Defines the context used during the {@link #writeTo(HttpServletRequest, HttpServletResponse, Context)}.
*/
interface Context {
/**
* Return the {@link HttpMessageConverter HttpMessageConverters} to be used for response body conversion.
* @return the list of message writers
*/
List> messageConverters();
}
}