Dynamic Sampling Support for Java

[zoesyc]

Description

In July, we added DS support for Android OkHttp. Here are some PRs created in the process: https://github.com/getsentry/sentry-java/pulls?q=is%3Apr+sort%3Aupdated-desc+baggage+is%3Aclosed.

https://develop.sentry.dev/sdk/performance/dynamic-sampling-context/

We want to extend the support to HTTP clients that we support, including OpenFeign, RestTemplate, apollo, etc.

Additionally, we need server-side support, meaning Spring and SpringBoot. We've built this for Python and Node so far - example:

• Dynamic Sampling Context / Baggage continuation sentry-python#1485

Main goals:

• Add baggage information to outgoing HTTP requests
• Context required for DS is included in the envelope headers

[adinauer]

We're already sending out the baggage header, what's missing is server side baggage support to pass through incoming baggage. For that we have #2085 to track.

Integrations already supporting outgoing baggage header:

• Feign:

  sentry-java/sentry-openfeign/src/main/java/io/sentry/openfeign/SentryFeignClient.java

  Lines 57 to 64 in eba572a

  	if (TracingOrigins.contain(hub.getOptions().getTracingOrigins(), url)) {
  	final SentryTraceHeader sentryTraceHeader = span.toSentryTrace();
  	final @Nullable BaggageHeader baggageHeader = span.toBaggageHeader();
  	requestWrapper.header(sentryTraceHeader.getName(), sentryTraceHeader.getValue());
  	if (baggageHeader != null) {
  	requestWrapper.header(baggageHeader.getName(), baggageHeader.getValue());
  	}
  	}

• OkHttp:

  sentry-java/sentry-android-okhttp/src/main/java/io/sentry/android/okhttp/SentryOkHttpInterceptor.kt

  Lines 39 to 46 in eba572a

  	if (span != null && TracingOrigins.contain(hub.options.tracingOrigins, request.url.toString())) {
  	span.toSentryTrace().let {
  	requestBuilder.addHeader(it.name, it.value)
  	}
  	span.toBaggageHeader()?.let {
  	requestBuilder.addHeader(it.name, it.value)
  	}
  	}

• Apollo v2:

  sentry-java/sentry-apollo/src/main/java/io/sentry/apollo/SentryApolloInterceptor.kt

  Lines 41 to 46 in eba572a

  	// we have no access to URI, no way to verify tracing origins
  	val requestHeaderBuilder = request.requestHeaders.toBuilder()
  	requestHeaderBuilder.addHeader(sentryTraceHeader.name, sentryTraceHeader.value)
  	span.toBaggageHeader()?.let {
  	requestHeaderBuilder.addHeader(it.name, it.value)
  	}

• Apollo v3:

  sentry-java/sentry-apollo-3/src/main/java/io/sentry/apollo3/SentryApollo3HttpInterceptor.kt

  Lines 39 to 47 in eba572a

  	if (TracingOrigins.contain(hub.options.tracingOrigins, request.url)) {
  	val sentryTraceHeader = span.toSentryTrace()
  	val baggageHeader = span.toBaggageHeader()
  	requestBuilder.addHeader(sentryTraceHeader.name, sentryTraceHeader.value)
  	baggageHeader?.let {
  	requestBuilder.addHeader(it.name, it.value)
  	}
  	}

• Spring WebClient:

  sentry-java/sentry-spring/src/main/java/io/sentry/spring/tracing/SentrySpanClientWebRequestFilter.java

  Lines 44 to 54 in eba572a

  	final SentryTraceHeader sentryTraceHeader = span.toSentryTrace();
  	final @Nullable BaggageHeader baggageHeader = span.toBaggageHeader();
  	final ClientRequest.Builder requestBuilder = ClientRequest.from(request);
  	if (TracingOrigins.contain(hub.getOptions().getTracingOrigins(), request.url())) {
  	requestBuilder.header(sentryTraceHeader.getName(), sentryTraceHeader.getValue());
  	if (baggageHeader != null) {
  	requestBuilder.header(baggageHeader.getName(), baggageHeader.getValue());
  	}
  	}

Is there something else missing?

[adinauer]

Ah looks like we missed Spring RestTemplate, here's the PR to add it: #2206