All Known Implementing Classes:
DefaultServerWebExchange, MockServerWebExchange, ServerWebExchangeDecorator
```
public interface ServerWebExchange
```
Contract for an HTTP request-response interaction. Provides access to the HTTP request and response and also exposes additional server-side processing related properties and features such as request attributes.
Since:
5.0
Author:
Rossen Stoyanchev

Nested Class Summary
Nested Classes
Modifier and Type Interface Description
static interface ServerWebExchange.Builder
Builder for mutating an existing ServerWebExchange.

Field Summary
Fields
Modifier and Type Field Description
static String LOG_ID_ATTRIBUTE
Name of attribute whose value can be used to correlate log messages for this exchange.

Method Summary

All Methods Instance Methods Abstract Methods Default Methods
Modifier and Type	Method	Description
`void`	`addUrlTransformer(Function<String,String> transformer)`	Register an additional URL transformation function for use with `transformUrl(java.lang.String)`.
`boolean`	`checkNotModified(String etag)`	An overloaded variant of `checkNotModified(String, Instant)` with an `ETag` (entity tag) value only.
`boolean`	`checkNotModified(String etag, Instant lastModified)`	Check whether the requested resource has been modified given the supplied `ETag` (entity tag) and last-modified timestamp as determined by the application.
`boolean`	`checkNotModified(Instant lastModified)`	An overloaded variant of `checkNotModified(String, Instant)` with a last-modified timestamp only.
`ApplicationContext`	`getApplicationContext()`	Return the `ApplicationContext` associated with the web application, if it was initialized with one via `WebHttpHandlerBuilder.applicationContext(ApplicationContext)`.
`default <T> T`	`getAttribute(String name)`	Return the request attribute value if present.
`default <T> T`	`getAttributeOrDefault(String name, T defaultValue)`	Return the request attribute value, or a default, fallback value.
`Map<String,Object>`	`getAttributes()`	Return a mutable map of request attributes for the current exchange.
`reactor.core.publisher.Mono<MultiValueMap<String,String>>`	`getFormData()`	Return the form data from the body of the request if the Content-Type is `"application/x-www-form-urlencoded"` or an empty map otherwise.
`LocaleContext`	`getLocaleContext()`	Return the `LocaleContext` using the configured `LocaleContextResolver`.
`String`	`getLogPrefix()`	Return a log message prefix to use to correlate messages for this exchange.
`reactor.core.publisher.Mono<MultiValueMap<String,Part>>`	`getMultipartData()`	Return the parts of a multipart request if the Content-Type is `"multipart/form-data"` or an empty map otherwise.
`<T extends Principal> reactor.core.publisher.Mono<T>`	`getPrincipal()`	Return the authenticated user for the request, if any.
`ServerHttpRequest`	`getRequest()`	Return the current HTTP request.
`default <T> T`	`getRequiredAttribute(String name)`	Return the request attribute value or if not present raise an `IllegalArgumentException`.
`ServerHttpResponse`	`getResponse()`	Return the current HTTP response.
`reactor.core.publisher.Mono<WebSession>`	`getSession()`	Return the web session for the current request.
`boolean`	`isNotModified()`	Returns `true` if the one of the `checkNotModified` methods in this contract were used and they returned true.
`default ServerWebExchange.Builder`	`mutate()`	Return a builder to mutate properties of this exchange by wrapping it with `ServerWebExchangeDecorator` and returning either mutated values or delegating back to this instance.
`String`	`transformUrl(String url)`	Transform the given url according to the registered transformation function(s).

- Field Detail
  - LOG_ID_ATTRIBUTE
```
static final String LOG_ID_ATTRIBUTE
```
    Name of attribute whose value can be used to correlate log messages for this exchange. Use getLogPrefix() to obtain a consistently formatted prefix based on this attribute.
    Since:
    5.1
    See Also:
    getLogPrefix()
- Method Detail
  - getRequest
```
ServerHttpRequest getRequest()
```
    Return the current HTTP request.
  - getResponse
```
ServerHttpResponse getResponse()
```
    Return the current HTTP response.
  - getAttributes
```
Map<String,Object> getAttributes()
```
    Return a mutable map of request attributes for the current exchange.
  - getAttribute
```
@Nullable
default <T> T getAttribute(String name)
```
    Return the request attribute value if present.
    Type Parameters:
    T - the attribute type
    Parameters:
    name - the attribute name
    Returns:
    the attribute value
  - getRequiredAttribute
```
default <T> T getRequiredAttribute(String name)
```
    Return the request attribute value or if not present raise an IllegalArgumentException.
    Type Parameters:
    T - the attribute type
    Parameters:
    name - the attribute name
    Returns:
    the attribute value
  - getAttributeOrDefault
```
default <T> T getAttributeOrDefault(String name,
                                    T defaultValue)
```
    Return the request attribute value, or a default, fallback value.
    Type Parameters:
    T - the attribute type
    Parameters:
    name - the attribute name
    defaultValue - a default value to return instead
    Returns:
    the attribute value
  - getSession
```
reactor.core.publisher.Mono<WebSession> getSession()
```
    Return the web session for the current request. Always guaranteed to return an instance either matching to the session id requested by the client, or with a new session id either because the client did not specify one or because the underlying session had expired. Use of this method does not automatically create a session. See WebSession for more details.
  - getPrincipal
```
<T extends Principal> reactor.core.publisher.Mono<T> getPrincipal()
```
    Return the authenticated user for the request, if any.
  - getFormData
```
reactor.core.publisher.Mono<MultiValueMap<String,String>> getFormData()
```
    Return the form data from the body of the request if the Content-Type is "application/x-www-form-urlencoded" or an empty map otherwise.
    Note: calling this method causes the request body to be read and parsed in full and the resulting MultiValueMap is cached so that this method is safe to call more than once.
  - getMultipartData
```
reactor.core.publisher.Mono<MultiValueMap<String,Part>> getMultipartData()
```
    Return the parts of a multipart request if the Content-Type is "multipart/form-data" or an empty map otherwise.
    Note: calling this method causes the request body to be read and parsed in full and the resulting MultiValueMap is cached so that this method is safe to call more than once.
    Note:the contents of each part is not cached, and can only be read once.
  - getLocaleContext
```
LocaleContext getLocaleContext()
```
    Return the LocaleContext using the configured LocaleContextResolver.
  - getApplicationContext
```
@Nullable
ApplicationContext getApplicationContext()
```
    Return the ApplicationContext associated with the web application, if it was initialized with one via WebHttpHandlerBuilder.applicationContext(ApplicationContext).
    Since:
    5.0.3
    See Also:
    WebHttpHandlerBuilder.applicationContext(ApplicationContext)
  - isNotModified
```
boolean isNotModified()
```
    Returns true if the one of the checkNotModified methods in this contract were used and they returned true.
  - checkNotModified
```
boolean checkNotModified(Instant lastModified)
```
    An overloaded variant of checkNotModified(String, Instant) with a last-modified timestamp only.
    Parameters:
    lastModified - the last-modified time
    Returns:
    whether the request qualifies as not modified
  - checkNotModified
```
boolean checkNotModified(String etag)
```
    An overloaded variant of checkNotModified(String, Instant) with an ETag (entity tag) value only.
    Parameters:
    etag - the entity tag for the underlying resource.
    Returns:
    true if the request does not require further processing.
  - checkNotModified
```
boolean checkNotModified(@Nullable
                         String etag,
                         Instant lastModified)
```
    Check whether the requested resource has been modified given the supplied ETag (entity tag) and last-modified timestamp as determined by the application. Also transparently prepares the response, setting HTTP status, and adding "ETag" and "Last-Modified" headers when applicable. This method works with conditional GET/HEAD requests as well as with conditional POST/PUT/DELETE requests.
    Note: The HTTP specification recommends setting both ETag and Last-Modified values, but you can also use #checkNotModified(String) or checkNotModified(Instant).
    Parameters:
    etag - the entity tag that the application determined for the underlying resource. This parameter will be padded with quotes (") if necessary.
    lastModified - the last-modified timestamp that the application determined for the underlying resource
    Returns:
    true if the request does not require further processing.
  - transformUrl
```
String transformUrl(String url)
```
    Transform the given url according to the registered transformation function(s). By default, this method returns the given url, though additional transformation functions can by registered with addUrlTransformer(java.util.function.Function<java.lang.String, java.lang.String>)
    Parameters:
    url - the URL to transform
    Returns:
    the transformed URL
  - addUrlTransformer
```
void addUrlTransformer(Function<String,String> transformer)
```
    Register an additional URL transformation function for use with transformUrl(java.lang.String). The given function can be used to insert an id for authentication, a nonce for CSRF protection, etc.
    Note that the given function is applied after any previously registered functions.
    Parameters:
    transformer - a URL transformation function to add
  - getLogPrefix
```
String getLogPrefix()
```
    Return a log message prefix to use to correlate messages for this exchange. The prefix is based on the value of the attribute LOG_ID_ATTRIBUTE along with some extra formatting so that the prefix can be conveniently prepended with no further formatting no separators required.
    Returns:
    the log message prefix or an empty String if the LOG_ID_ATTRIBUTE is not set.
    Since:
    5.1
  - mutate
```
default ServerWebExchange.Builder mutate()
```
    Return a builder to mutate properties of this exchange by wrapping it with ServerWebExchangeDecorator and returning either mutated values or delegating back to this instance.

Interface ServerWebExchange

Nested Class Summary

Field Summary

Method Summary

Field Detail

LOG_ID_ATTRIBUTE

Method Detail

getRequest

getResponse

getAttributes

getAttribute

getRequiredAttribute

getAttributeOrDefault

getSession

getPrincipal

getFormData

getMultipartData

getLocaleContext

getApplicationContext

isNotModified

checkNotModified

checkNotModified

checkNotModified

transformUrl

addUrlTransformer

getLogPrefix

mutate