Fixes how Python Workers treats duplicate headers #5915
+84
−10
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…as and distinct Set-Cookie values
hoodmane
reviewed
Jan 16, 2026
| def _preserve_request_header_commas() -> bool: | ||
| try: | ||
| import _cloudflare_compat_flags as compat_flags | ||
| except Exception: |
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Suggested change
| except Exception: | |
| except ImportError: |
hoodmane
reviewed
Jan 16, 2026
| except Exception: | ||
| return False | ||
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| return bool(getattr(compat_flags, "python_request_headers_preserve_commas", False)) |
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Do we need the bool part?
Suggested change
| return bool(getattr(compat_flags, "python_request_headers_preserve_commas", False)) | |
| return getattr(compat_flags, "python_request_headers_preserve_commas", False) |
hoodmane
reviewed
Jan 16, 2026
| return hasattr(val, "constructor") and val.constructor.name == js_cls_name | ||
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| def _preserve_request_header_commas() -> bool: |
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Why not make this into a helper method like this:
try:
import _cloudflare_compat_flags
except ImportError:
_cloudflare_compat_flags = object()
def get_compat_flag(flag: string) -> bool:
return getattr(_cloudflare_compat_flags, flag, false)
ryanking13
approved these changes
Jan 19, 2026
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ryanking13
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Thanks for handling this.
| pythonRequestHeadersPreserveCommas @155 :Bool | ||
| $compatEnableFlag("python_request_headers_preserve_commas") | ||
| $compatDisableFlag("disable_python_request_headers_preserve_commas") | ||
| $compatEnableDate("2026-02-04"); |
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I am curious why are we setting the compat date to a lot future?
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Based on #5678 (thank you @n3rada for reporting and helping out with the fix)
All duplicate headers except Set-Cookie will now be added to Python's http.client.HTTPMessage combined and separated by commas.
Test Plan