xds: ignore keep_empty_value and discard header keys on empty mutations#12852
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kannanjgithub merged 3 commits intoJun 22, 2026
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In GrpcService/ext_proc header mutations, we do not support the `keep_empty_value` field (grpc/proposal@f6d42d6). If any header mutation results in a header containing an empty value (either string or binary), the entire header key is discarded/removed from the metadata. This chang modifies HeaderMutator to apply mutations and discard keys containing empty values.
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/gemini review |
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/gemini-review |
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This pull request refactors the header mutation logic in HeaderMutator.java to discard headers containing empty values, updating the corresponding test cases in HeaderMutatorTest.java to reflect this change. A review comment suggests that the newly added containsEmpty helper method is redundant and can be safely removed.
sauravzg
reviewed
Jun 10, 2026
sauravzg
approved these changes
Jun 10, 2026
Updates the HeaderMutator library to always apply mutations even if the resulting value is empty, ignoring the keep_empty_value setting altogether. Empty mutated values are now kept in the metadata and the header key is no longer discarded. - Removes containsEmpty check and helper from HeaderMutator. - Updates HeaderMutatorTest to assert that empty mutations are kept.
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I'm retaining the empty value now (same as Envoy), not removing it. |
sauravzg
approved these changes
Jun 22, 2026
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In GrpcService/ext_proc header mutations, we do not support the
keep_empty_valuefield (grpc/proposal@f6d42d6). If any header mutation results in a header containing an empty value (either string or binary), we proceed with the empty value.