284184 2024-12-06 12:35:26 -0800 Checking for presence of request body in Service Worker causes body to be dropped from request 2025-01-07 01:04:20 -0800 1 1 1 Unclassified WebKit Service Workers Safari 18 All All RESOLVED FIXED https://github.com/web-platform-tests/wpt/pull/49923 InRadar P2 Normal --- 1 wes webkit-unassigned achristensen annevk cdumez webkit-bug-importer youennf oldest_to_newest 2079710 0 wes 2024-12-06 12:35:26 -0800 If a service worker intercepts a fetch request and checks for the presence of a body then the body will get dropped from the SW's fetch request. NOTE: I have tried this with both "Content-Type: application/json" and "Content-Type: x-www-form-urlencoded" and both hit this bug. > // sw code > self.addEventListener("fetch", (event) => { > event.respondWith( > (async () => { > if (event.request.body) { > console.log("this request has a body"); > } > return fetch(event.request); > })() > ); >}); I have made a repro at https://github.com/wes-goulet/webkit-service-worker-drop-body-repro This same check of a request body causes no issue if it happens on the main thread (not in SW). 2081593 1 webkit-bug-importer 2024-12-13 12:36:14 -0800 <rdar://problem/141454387> 2085073 2 youennf 2025-01-06 09:17:14 -0800 Submitted web-platform-tests pull request: https://github.com/web-platform-tests/wpt/pull/49923 2085349 3 ews-feeder 2025-01-07 01:04:17 -0800 Committed 288514@main (6c800745251d): <https://commits.webkit.org/288514@main> Reviewed commits have been landed. Closing PR #38561 and removing active labels.