feat: Add propagating of traceparent #6356

philipphofmann · 2025-10-06T09:05:15Z

📜 Description

Added support for OTel/W3C trace propagation by introducing a new option enablePropagateTraceparent that controls whether the SDK adds the W3C traceparent HTTP header to outgoing requests.

Docs PR getsentry/sentry-docs#15159

💡 Motivation and Context

Fixes GH-6017

💚 How did you test it?

Added unit tests to verify the traceparent header is correctly added when the feature is enabled and not added when disabled. Also tested that existing headers aren't overridden.

📝 Checklist

You have to check all boxes before merging:

I added tests to verify the changes.
No new PII added or SDK only sends newly added PII if sendDefaultPII is enabled.
I updated the docs if needed.
I updated the wizard if needed.
Review from the native team if needed.
No breaking change or entry added to the changelog.
No breaking change for hybrid SDKs or communicated to hybrid SDKs.

philipphofmann · 2025-10-06T09:05:38Z

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github-actions · 2025-10-06T09:05:46Z

	Messages
📖	Do not forget to update Sentry-docs with your feature once the pull request gets approved.

Generated by 🚫 dangerJS against 1b58355

codecov · 2025-10-06T09:28:30Z

❌ 3 Tests Failed:

Tests completed	Failed	Passed	Skipped
4019	3	4016	31

View the top 3 failed test(s) by shortest run time

iOS_Swift_UITests.LaunchUITests::testCaptureException

Stack Traces | 0s run time

.../iOS-Swift/iOS-Swift-UITests/LaunchUITests.swift:43 - Failed to Error Domain=com.apple.dt.XCTest.XCTFuture Code=1000 "Timed out while evaluating UI query." UserInfo={NSLocalizedDescription=Timed out while evaluating UI query.}: Timed out while evaluating UI query.

iOS_Swift_UITests.LaunchUITests::testCheckSlowAndFrozenFrames

Stack Traces | 0s run time

.../iOS-Swift/iOS-Swift-UITests/LaunchUITests.swift:66 - Failed to Error Domain=com.apple.dt.XCTest.XCTFuture Code=1000 "Timed out while evaluating UI query." UserInfo={NSLocalizedDescription=Timed out while evaluating UI query.}: Timed out while evaluating UI query.

iOS_Swift_UITests.LaunchUITests::testLoremIpsum

Stack Traces | 0s run time

.../iOS-Swift/iOS-Swift-UITests/LaunchUITests.swift:14 - Failed to Error Domain=com.apple.dt.XCTest.XCTFuture Code=1000 "Timed out while evaluating UI query." UserInfo={NSLocalizedDescription=Timed out while evaluating UI query.}: Timed out while evaluating UI query.

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github-actions · 2025-10-06T10:32:45Z

Performance metrics 🚀

	Plain	With Sentry	Diff
Startup time	1230.08 ms	1262.12 ms	32.03 ms
Size	23.75 KiB	1005.85 KiB	982.10 KiB

Baseline results on branch: main

Startup times

Revision	Plain	With Sentry	Diff
`570f725`	1206.00 ms	1238.96 ms	32.96 ms
`ab0ba7e`	1216.08 ms	1242.40 ms	26.31 ms
`a6f5396`	1211.81 ms	1245.63 ms	33.82 ms
`6502818`	1229.08 ms	1245.46 ms	16.37 ms
`04ff3ec`	1220.71 ms	1253.86 ms	33.15 ms
`c122943`	1210.94 ms	1233.78 ms	22.84 ms
`59fc426`	1240.49 ms	1256.94 ms	16.45 ms
`397b9c9`	1230.23 ms	1249.29 ms	19.06 ms
`51b7dd3`	1235.06 ms	1258.21 ms	23.15 ms
`2a6f451`	1212.89 ms	1237.45 ms	24.56 ms

App size

Revision	Plain	With Sentry	Diff
`570f725`	23.74 KiB	913.38 KiB	889.63 KiB
`ab0ba7e`	23.75 KiB	904.54 KiB	880.79 KiB
`a6f5396`	23.75 KiB	989.12 KiB	965.38 KiB
`6502818`	23.75 KiB	959.45 KiB	935.70 KiB
`04ff3ec`	23.75 KiB	880.26 KiB	856.52 KiB
`c122943`	23.74 KiB	926.65 KiB	902.90 KiB
`59fc426`	23.75 KiB	920.64 KiB	896.89 KiB
`397b9c9`	23.75 KiB	959.44 KiB	935.70 KiB
`51b7dd3`	23.75 KiB	913.26 KiB	889.52 KiB
`2a6f451`	23.75 KiB	913.13 KiB	889.38 KiB

Previous results on branch: feat_add_propagating_of_traceparent

Startup times

Revision	Plain	With Sentry	Diff
`fec69f5`	1233.02 ms	1266.88 ms	33.85 ms
`1c5ce84`	1219.49 ms	1249.06 ms	29.57 ms
`ed645d9`	1219.76 ms	1255.91 ms	36.16 ms
`786f095`	1231.33 ms	1261.23 ms	29.90 ms
`fe4d5d5`	1237.80 ms	1253.33 ms	15.53 ms
`dea0f9c`	1227.83 ms	1262.15 ms	34.32 ms

App size

Revision	Plain	With Sentry	Diff
`fec69f5`	23.75 KiB	987.44 KiB	963.69 KiB
`1c5ce84`	23.75 KiB	987.45 KiB	963.70 KiB
`ed645d9`	23.75 KiB	995.62 KiB	971.87 KiB
`786f095`	23.75 KiB	988.54 KiB	964.80 KiB
`fe4d5d5`	23.75 KiB	990.49 KiB	966.74 KiB
`dea0f9c`	23.75 KiB	990.65 KiB	966.90 KiB

noahsmartin · 2025-10-08T03:26:31Z

It looks like you might have ran the api file generation using Xcode 26, CI uses 16.4 so it won't pass CI unless you use that. This was because Xcode 26 doesn't include the objc public API (only Swift)

Add the option propagateTraceparent, which is disabled by default. When enabled, it adds the W3C Trace Context HTTP header traceparent on outgoing HTTP requests. This is useful when the receiving services only support OTel/W3C propagation. Fixes GH-6017

github-actions · 2025-10-15T09:42:59Z

🚨 Detected changes in high risk code 🚨

High-risk code can easily blow up and is hard to test. We had severe bugs in the past. Be extra careful when changing these files, and have an extra careful look at these:

Sources/Sentry/SentryNetworkTracker.m

This was referenced Oct 6, 2025

ref: Move trace propagation to its own class #6337

Merged

test: Extract isTargetTests to own test class #6352

Merged

ref: Remove SentrySDK from trace propagation class #6354

Merged

philipphofmann marked this pull request as ready for review October 6, 2025 09:06

philipphofmann requested review from itaybre, noahsmartin and philprime as code owners October 6, 2025 09:06