fix: clone response before setting baseline security headers#509
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ascorbic merged 4 commits intoemdash-cms:mainfrom Apr 13, 2026
Merged
fix: clone response before setting baseline security headers#509ascorbic merged 4 commits intoemdash-cms:mainfrom
ascorbic merged 4 commits intoemdash-cms:mainfrom
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On Cloudflare, some responses (e.g. /_image/* from Astro image transform) have immutable headers. Cloning into a new Response avoids the TypeError. Fixes emdash-cms#506
🦋 Changeset detectedLatest commit: 3a1eeef The changes in this PR will be included in the next version bump. This PR includes changesets to release 9 packages
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@emdash-cms/admin
@emdash-cms/auth
@emdash-cms/blocks
@emdash-cms/cloudflare
emdash
create-emdash
@emdash-cms/gutenberg-to-portable-text
@emdash-cms/x402
@emdash-cms/plugin-ai-moderation
@emdash-cms/plugin-atproto
@emdash-cms/plugin-audit-log
@emdash-cms/plugin-color
@emdash-cms/plugin-embeds
@emdash-cms/plugin-forms
@emdash-cms/plugin-webhook-notifier
commit: |
hayatosc
reviewed
Apr 13, 2026
| */ | ||
| function setBaselineSecurityHeaders(response: Response): void { | ||
| function setBaselineSecurityHeaders(response: Response): Response { | ||
| const headers = new Headers(response.headers); |
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In Using the Cache API on Cloudflare Docs , the approach of using response = new Response(response.body, response) is employed to clone a response.
Don't you think this method would be considered better?
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Good call - updated in 3a1eeef to use new Response(response.body, response) per the Cloudflare docs pattern. Cleaner than manually extracting status/statusText.
Use `new Response(response.body, response)` to clone the response before setting security headers, following the Cloudflare Workers Cache API pattern. This eliminates manual extraction of status and statusText properties.
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fmhall
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Apr 13, 2026
…cms#509) * fix: clone response before setting baseline security headers On Cloudflare, some responses (e.g. /_image/* from Astro image transform) have immutable headers. Cloning into a new Response avoids the TypeError. Fixes emdash-cms#506 * chore: add changeset for immutable headers fix * style: format * refactor: use Cloudflare docs pattern for response cloning Use `new Response(response.body, response)` to clone the response before setting security headers, following the Cloudflare Workers Cache API pattern. This eliminates manual extraction of status and statusText properties. --------- Co-authored-by: Matt Van Horn <455140+mvanhorn@users.noreply.github.com> Co-authored-by: emdashbot[bot] <emdashbot[bot]@users.noreply.github.com>
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What does this PR do?
setBaselineSecurityHeadersinpackages/core/src/astro/middleware.tscallsresponse.headers.set()directly on the Response returned bynext(). On Cloudflare, some responses (e.g./_image/*from Astro's image transform endpoint) have immutable headers, causingTypeError: Can't modify immutable headers.This PR changes the function to create a new
Responsewith cloned headers before modifying them. The original response body, status, and statusText are preserved. All three call sites in the middleware are updated.Closes #506
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Checklist
pnpm typecheckpassespnpm lintpassespnpm testpasses (or targeted tests for my change)pnpm formathas been runpnpm locale:extracthas been run (if applicable)AI-generated code disclosure
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pnpm --silent lint:quickreturns 0 diagnostics.