Envoy should not alter thrift THeader key

[fishy]

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Currently envoy always lowercase thrift THeader key and this is wrong

Description:
Thrift THeader keys are case-sensitive according to the spec, so altering them is a bug.

This is the line that does it:

envoy/source/extensions/filters/network/thrift_proxy/header_transport_impl.cc

Line 151 in 0fae697

const Http::LowerCaseString key = Http::LowerCaseString(key_string);

Repro steps:
Make a thrift client and send "Foo: Bar" THeader to a thrift server via envoy. The server receives "foo: Bar" instead.

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[marcoferrer]

Linking thrift issue requesting clarification on key format in the header spec
https://issues.apache.org/jira/browse/THRIFT-5541

[daixiang0]

Good catch, we should follow the spec.

[github-actions]

This issue has been automatically marked as stale because it has not had activity in the last 30 days. It will be closed in the next 7 days unless it is tagged "help wanted" or "no stalebot" or other activity occurs. Thank you for your contributions.

[fishy]

not stale

[github-actions]

This issue has been automatically marked as stale because it has not had activity in the last 30 days. It will be closed in the next 7 days unless it is tagged "help wanted" or "no stalebot" or other activity occurs. Thank you for your contributions.

[github-actions]

This issue has been automatically closed because it has not had activity in the last 37 days. If this issue is still valid, please ping a maintainer and ask them to label it as "help wanted" or "no stalebot". Thank you for your contributions.