Class ServerHttpObservationFilter

java.lang.Object

org.springframework.web.filter.GenericFilterBean

org.springframework.web.filter.OncePerRequestFilter

org.springframework.web.filter.ServerHttpObservationFilter

All Implemented Interfaces:

jakarta.servlet.Filter, Aware, BeanNameAware, DisposableBean, InitializingBean, EnvironmentAware, EnvironmentCapable, ServletContextAware

public class ServerHttpObservationFilter
extends OncePerRequestFilter

Filter that creates observations for HTTP exchanges. This collects information about the execution time and information gathered from the ServerRequestObservationContext.

web Frameworks can fetch the current context as a request attribute and contribute additional information to it. The configured ServerRequestObservationConvention will use this context to collect metadata and attach it to the observation.

Since:

6.0

Author:

Brian Clozel

Field Summary

Fields

Modifier and Type	Field	Description
static final String	CURRENT_OBSERVATION_CONTEXT_ATTRIBUTE	Name of the request attribute holding the ServerRequestObservationContext for the current observation.

Fields inherited from class OncePerRequestFilter

ALREADY_FILTERED_SUFFIX

Fields inherited from class GenericFilterBean

logger

Constructor Summary

Constructors

Constructor	Description
ServerHttpObservationFilter(io.micrometer.observation.ObservationRegistry observationRegistry)	Create an HttpRequestsObservationFilter that records observations against the given ObservationRegistry.
ServerHttpObservationFilter(io.micrometer.observation.ObservationRegistry observationRegistry, ServerRequestObservationConvention observationConvention)	Create an HttpRequestsObservationFilter that records observations against the given ObservationRegistry with a custom convention.

Method Summary

Modifier and Type	Method	Description
protected void	doFilterInternal(jakarta.servlet.http.HttpServletRequest request, jakarta.servlet.http.HttpServletResponse response, jakarta.servlet.FilterChain filterChain)	Same contract as for doFilter, but guaranteed to be just invoked once per request within a single request thread.
static Optional<ServerRequestObservationContext>	findObservationContext(jakarta.servlet.http.HttpServletRequest request)	Get the current observation context from the given request, if available.
protected void	onScopeOpened(io.micrometer.observation.Observation.Scope scope, jakarta.servlet.http.HttpServletRequest request, jakarta.servlet.http.HttpServletResponse response)	Notify this filter that a new Observation.Scope is opened for the observation that was just created.
protected boolean	shouldNotFilterAsyncDispatch()	The dispatcher type jakarta.servlet.DispatcherType.ASYNC means a filter can be invoked in more than one thread over the course of a single request.

Methods inherited from class OncePerRequestFilter

doFilter, doFilterNestedErrorDispatch, getAlreadyFilteredAttributeName, isAsyncDispatch, isAsyncStarted, shouldNotFilter, shouldNotFilterErrorDispatch

Methods inherited from class GenericFilterBean

addRequiredProperty, afterPropertiesSet, createEnvironment, destroy, getEnvironment, getFilterConfig, getFilterName, getServletContext, init, initBeanWrapper, initFilterBean, setBeanName, setEnvironment, setServletContext

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

CURRENT_OBSERVATION_CONTEXT_ATTRIBUTE

public static final String CURRENT_OBSERVATION_CONTEXT_ATTRIBUTE

Name of the request attribute holding the ServerRequestObservationContext for the current observation.

Constructor Details

ServerHttpObservationFilter

public ServerHttpObservationFilter(io.micrometer.observation.ObservationRegistry observationRegistry)

Create an HttpRequestsObservationFilter that records observations against the given ObservationRegistry. The default convention will be used.

Parameters:

observationRegistry - the registry to use for recording observations

ServerHttpObservationFilter

public ServerHttpObservationFilter(io.micrometer.observation.ObservationRegistry observationRegistry,
 ServerRequestObservationConvention observationConvention)

Create an HttpRequestsObservationFilter that records observations against the given ObservationRegistry with a custom convention.

Parameters:

observationRegistry - the registry to use for recording observations

observationConvention - the convention to use for all recorded observations

Method Details

shouldNotFilterAsyncDispatch

protected boolean shouldNotFilterAsyncDispatch()

Description copied from class: OncePerRequestFilter

The dispatcher type jakarta.servlet.DispatcherType.ASYNC means a filter can be invoked in more than one thread over the course of a single request. Some filters only need to filter the initial thread (for example, request wrapping) while others may need to be invoked at least once in each additional thread for example for setting up thread locals or to perform final processing at the very end.

Note that although a filter can be mapped to handle specific dispatcher types via web.xml or in Java through the ServletContext, servlet containers may enforce different defaults with respect to dispatcher types. This flag enforces the design intent of the filter.

The default return value is "true", which means the filter will not be invoked during subsequent async dispatches. If "false", the filter will be invoked during async dispatches with the same guarantees of being invoked only once during a request within a single thread.

Overrides:

shouldNotFilterAsyncDispatch in class OncePerRequestFilter

doFilterInternal

protected void doFilterInternal(jakarta.servlet.http.HttpServletRequest request,
 jakarta.servlet.http.HttpServletResponse response,
 jakarta.servlet.FilterChain filterChain)
                         throws jakarta.servlet.ServletException,
IOException

Description copied from class: OncePerRequestFilter

Same contract as for doFilter, but guaranteed to be just invoked once per request within a single request thread. See OncePerRequestFilter.shouldNotFilterAsyncDispatch() for details.

Provides HttpServletRequest and HttpServletResponse arguments instead of the default ServletRequest and ServletResponse ones.

Specified by:

doFilterInternal in class OncePerRequestFilter

Throws:

jakarta.servlet.ServletException

IOException

onScopeOpened

protected void onScopeOpened(io.micrometer.observation.Observation.Scope scope,
 jakarta.servlet.http.HttpServletRequest request,
 jakarta.servlet.http.HttpServletResponse response)

Notify this filter that a new Observation.Scope is opened for the observation that was just created.

Parameters:

scope - the newly opened observation scope

request - the HTTP client request

response - the filter's response

Since:

6.2

findObservationContext

public static Optional<ServerRequestObservationContext> findObservationContext(jakarta.servlet.http.HttpServletRequest request)

Get the current observation context from the given request, if available.

Parameters:

request - the current request

Returns:

the current observation context