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Create a EnvoyFilter file (e.g. envoyfilter-case.yaml)
Code Block apiVersion: networking.istio.io/v1alpha3 kind: EnvoyFilter metadata: name: header-casing namespace: istio-confiigconfig spec: configPatches: - applyTo: CLUSTER match: context: ANY patch: operation: MERGE value: typed_extension_protocol_options: envoy.extensions.upstreams.http.v3.HttpProtocolOptions: '@type': type.googleapis.com/envoy.extensions.upstreams.http.v3.HttpProtocolOptions use_downstream_protocol_config: http_protocol_options: header_key_format: stateful_formatter: name: preserve_case typed_config: '@type': type.googleapis.com/envoy.extensions.http.header_formatters.preserve_case.v3.PreserveCaseFormatterConfig - applyTo: NETWORK_FILTER match: listener: filterChain: filter: name: envoy.filters.network.http_connection_manager patch: operation: MERGE value: typed_config: '@type': type.googleapis.com/envoy.extensions.filters.network.http_connection_manager.v3.HttpConnectionManager http_protocol_options: header_key_format: stateful_formatter: name: preserve_case typed_config: '@type': type.googleapis.com/envoy.extensions.http.header_formatters.preserve_case.v3.PreserveCaseFormatterConfig
Apply the change to Istio
Code Block $ kubectl apply -f envoyfilter-case.yaml
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