fix: preserve raw headers in dispatch handler bridge#5345
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Signed-off-by: Matteo Collina <hello@matteocollina.com>
Codecov Report✅ All modified and coverable lines are covered by tests. Additional details and impacted files@@ Coverage Diff @@
## v7.x #5345 +/- ##
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- Coverage 92.91% 92.90% -0.01%
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Files 112 112
Lines 35837 35843 +6
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+ Hits 33297 33299 +2
- Misses 2540 2544 +4 ☔ View full report in Codecov by Sentry. 🚀 New features to boost your workflow:
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ronag
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Jun 3, 2026
metcoder95
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QuiiBz
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Closes #198 Update the Undici version we use to fix an issue where using Undici v7 `Agent` with a Undici v8 `fetch` (e.g. using Node.js 26 with the global, bundled `fetch`) would cause response headers to be dropped, and response body to not be decompressed Upstream Undici fix: nodejs/undici#5345
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Description
Preserve
rawHeadersandrawTrailerson the synthetic controller used byUnwrapHandlerwhen bridging modern dispatch handlers to the legacy handler interface.This keeps Node.js bundled
fetchcompatible with an imported Undici v7Agent, so response headers remain visible and compressed bodies continue to be decoded.Fixes: #5341
Changes
rawHeaderson the controller before invokingonRequestUpgrade/onResponseStartrawTrailersbefore invokingonResponseEndtypes/dispatcher.d.tsfetchwith both the global dispatcher and an explicitdispatcher: new Agent()Testing
npm run lint -- lib/handler/unwrap-handler.js test/node-test/global-dispatcher-version.js types/dispatcher.d.tsnpx borp -p "test/node-test/global-dispatcher-version.js"source ~/.nvm/nvm.sh && nvm use 26.3.0 >/dev/null && npx borp -p "test/node-test/global-dispatcher-version.js"