As of spring-projects/spring-framework#28341, `WebClient` is
instrumented directly for `Observation`.
This commit removes the custom `ExchangeFilterFunction` that previously
instrumented the client for metrics.
As a result, the relevant tag providers are now deprecated and adapted
as `ObservationConvention` for the time being.
Closes gh-32518
This commit migrates our remaining usage of the httpclient 4.x to use
instead httpclient5, now that the 4.x support has been removed in
`RestTemplate`.
Closes gh-32461
This commit adapts the `TestRestTemplate` implementation to the
httpclient5 API since httpclient 4.x is now unsupported in Spring
Framework.
See gh-32461
Prior to this commit, the `RestTemplateBuilder` would offer a generic
`setReadTimeout` method to configure the read timeout on the underlying
`ClientHttpRequestFactory`. This would be done in a reflective fashion,
considering that all implementations align with this behavior.
This option cannot be provided for HttpClient5 at the
`ClientHttpRequestFactory` level anymore, so this has been deprecated
in Spring Framework 6.0 and will log a warning. In order to align with
our existing behavior (throwing exceptions if the option cannot be set),
this commit ensures that exceptions are also thrown if the method is
marked as deprecated.
See gh-32461
As htttpclient 4.x is not supported anymore by `RestTemplate`, this
commit changes such dependencies to httpclient5 instead. In some cases,
the httpclient 4.x was transitively brought by a non-Spring dependency.
See gh-32461
Previously, RestTemplateBuilder and WebClient.Builder beans were used
to create the HTTP client for sending out spans. Those same beans are
also instrumented for observability which results in a cycle.
This commit breaks the cycle by not using the application-web
builders to create the RestTemplate and WebClient's used by the Zipkin
senders. Instead, builders are created inline, with new callbacks
being introduced to allow the user to customize these Zipkin-specific
builders.
See gh-32528
Phillip Webb
Scott Frederick
Andy Wilkinson
Stephane Nicoll
Brian Clozel
dreis2211
Marcin Grzejszczak