http: remove getAll() header map API and switch all usages to get()

api/envoy/api/v2/cluster.proto

@@ -352,6 +352,10 @@ message Cluster {
     //   This header isn't sanitized by default, so enabling this feature allows HTTP clients to
     //   route traffic to arbitrary hosts and/or ports, which may have serious security
     //   consequences.
+    //
+    // .. note::
+    //
+    //   If the header appears multiple times only the first value is used.
     bool use_http_header = 1;
   }
 

api/envoy/api/v2/route/route_components.proto

@@ -756,6 +756,10 @@ message RouteAction {
     //
     //   Internally, Envoy always uses the HTTP/2 *:authority* header to represent the HTTP/1
     //   *Host* header. Thus, if attempting to match on *Host*, match on *:authority* instead.
+    //
+    // .. note::
+    //
+    //   If the header appears multiple times only the first value is used.
     string cluster_header = 2
         [(validate.rules).string = {min_bytes: 1 well_known_regex: HTTP_HEADER_NAME strict: false}];
 
@@ -866,6 +870,10 @@ message RouteAction {
     //
     //   Pay attention to the potential security implications of using this option. Provided header
     //   must come from trusted source.
+    //
+    // .. note::
+    //
+    //   If the header appears multiple times only the first value is used.
     string auto_host_rewrite_header = 29 [
       (validate.rules).string = {well_known_regex: HTTP_HEADER_NAME strict: false},
       (udpa.annotations.field_migrate).rename = "host_rewrite_header"

api/envoy/config/cluster/v3/cluster.proto

@@ -436,6 +436,10 @@ message Cluster {
     //   This header isn't sanitized by default, so enabling this feature allows HTTP clients to
     //   route traffic to arbitrary hosts and/or ports, which may have serious security
     //   consequences.
+    //
+    // .. note::
+    //
+    //   If the header appears multiple times only the first value is used.
     bool use_http_header = 1;
   }
 

api/envoy/config/filter/http/dynamic_forward_proxy/v2alpha/dynamic_forward_proxy.proto

@@ -51,6 +51,10 @@ message PerRouteConfig {
     // :ref:`HCM host rewrite header <envoy_api_field_route.RouteAction.auto_host_rewrite_header>`
     // given that the value set here would be used for DNS lookups whereas the value set in the HCM
     // would be used for host header forwarding which is not the desired outcome.
+    //
+    // .. note::
+    //
+    //   If the header appears multiple times only the first value is used.
     string auto_host_rewrite_header = 2
         [(udpa.annotations.field_migrate).rename = "host_rewrite_header"];
   }

api/envoy/config/filter/network/http_connection_manager/v2/http_connection_manager.proto

@@ -586,6 +586,10 @@ message ScopedRoutes {
         }
 
         // The name of the header field to extract the value from.
+        //
+        // .. note::
+        //
+        //   If the header appears multiple times only the first value is used.
         string name = 1 [(validate.rules).string = {min_bytes: 1}];
 
         // The element separator (e.g., ';' separates 'a;b;c;d').

api/envoy/config/route/v3/route_components.proto

@@ -809,6 +809,10 @@ message RouteAction {
     //
     //   Internally, Envoy always uses the HTTP/2 *:authority* header to represent the HTTP/1
     //   *Host* header. Thus, if attempting to match on *Host*, match on *:authority* instead.
+    //
+    // .. note::
+    //
+    //   If the header appears multiple times only the first value is used.
     string cluster_header = 2
         [(validate.rules).string = {min_len: 1 well_known_regex: HTTP_HEADER_NAME strict: false}];
 
@@ -917,6 +921,10 @@ message RouteAction {
     //
     //   Pay attention to the potential security implications of using this option. Provided header
     //   must come from trusted source.
+    //
+    // .. note::
+    //
+    //   If the header appears multiple times only the first value is used.
     string host_rewrite_header = 29
         [(validate.rules).string = {well_known_regex: HTTP_HEADER_NAME strict: false}];
 
@@ -1146,9 +1154,15 @@ message RetryPolicy {
   }
 
   message ResetHeader {
+    // The name of the reset header.
+    //
+    // .. note::
+    //
+    //   If the header appears multiple times only the first value is used.
     string name = 1
         [(validate.rules).string = {min_len: 1 well_known_regex: HTTP_HEADER_NAME strict: false}];
 
+    // The format of the reset header.
     ResetHeaderFormat format = 2 [(validate.rules).enum = {defined_only: true}];
   }
 

api/envoy/extensions/filters/http/dynamic_forward_proxy/v3/dynamic_forward_proxy.proto

@@ -55,6 +55,10 @@ message PerRouteConfig {
     // :ref:`HCM host rewrite header <envoy_api_field_config.route.v3.RouteAction.auto_host_rewrite>`
     // given that the value set here would be used for DNS lookups whereas the value set in the HCM
     // would be used for host header forwarding which is not the desired outcome.
+    //
+    // .. note::
+    //
+    //   If the header appears multiple times only the first value is used.
     string host_rewrite_header = 2;
   }
 }

api/envoy/extensions/filters/network/http_connection_manager/v3/http_connection_manager.proto

@@ -725,6 +725,10 @@ message ScopedRoutes {
         }
 
         // The name of the header field to extract the value from.
+        //
+        // .. note::
+        //
+        //   If the header appears multiple times only the first value is used.
         string name = 1 [(validate.rules).string = {min_len: 1}];
 
         // The element separator (e.g., ';' separates 'a;b;c;d').

ci/filter_example_setup.sh

@@ -5,7 +5,7 @@
 set -e
 
 # This is the hash on https://github.com/envoyproxy/envoy-filter-example.git we pin to.
-ENVOY_FILTER_EXAMPLE_GITSHA="493e2e5bee10bbed1c3c097e09d83d7f672a9f2e"
+ENVOY_FILTER_EXAMPLE_GITSHA="bebd0b2422ea7739905f1793565681d7266491e6"
 ENVOY_FILTER_EXAMPLE_SRCDIR="${BUILD_DIR}/envoy-filter-example"
 
 # shellcheck disable=SC2034

docs/root/configuration/http/http_filters/fault_filter.rst

@@ -38,7 +38,7 @@ fault configuration. The currently supported header controls are:
 
 x-envoy-fault-abort-request
   HTTP status code to abort a request with. The header value should be an integer that specifies
-  the HTTP status code to return in response to a request and must be in the range [200, 600). 
+  the HTTP status code to return in response to a request and must be in the range [200, 600).
   In order for the header to work, :ref:`header_abort
   <envoy_v3_api_field_extensions.filters.http.fault.v3.FaultAbort.header_abort>` needs to be set.
 
@@ -47,8 +47,8 @@ x-envoy-fault-abort-grpc-request
   the gRPC status code to return in response to a request. Its value range is [0, UInt32.Max] instead of [0, 16]
   to allow testing even not well-defined gRPC status codes. When this header is set, the HTTP response status code
   will be set to 200. In order for the header to work, :ref:`header_abort
-  <envoy_api_field_config.filter.http.fault.v2.FaultAbort.header_abort>` needs to be set. If both 
-  *x-envoy-fault-abort-request* and *x-envoy-fault-abort-grpc-request* headers are set then 
+  <envoy_api_field_config.filter.http.fault.v2.FaultAbort.header_abort>` needs to be set. If both
+  *x-envoy-fault-abort-request* and *x-envoy-fault-abort-grpc-request* headers are set then
   *x-envoy-fault-abort-grpc-request* header will be **ignored** and fault response http status code will be
   set to *x-envoy-fault-abort-request* header value.
 
@@ -105,6 +105,10 @@ x-envoy-fault-throughput-response-percentage
   <envoy_v3_api_field_extensions.filters.http.fault.v3.HTTPFault.max_active_faults>` setting to limit the
   maximum concurrent faults that can be active at any given time.
 
+.. note::
+
+  If the headers appear multiple times only the first value is used.
+
 The following is an example configuration that enables header control for both of the above
 options: