address comments

Signed-off-by: Huabing (Robin) Zhao <zhaohuabing@gmail.com>

Author: zhaohuabing

api/v1alpha1/backendtrafficpolicy_types.go

@@ -134,6 +134,19 @@ type BackendTrafficPolicySpec struct {
 
 	// RequestBodyBufferLimit specifies the maximum size in bytes that Envoy may buffer for request bodies.
 	// This configures Envoy's request body buffer limit without enabling full request buffering.
+	//
+	// This Request body buffer limit is independent of the connection buffer limits configured by
+    // ClientTrafficPolicy and BackendTrafficPolicy. The connection buffer limits control downstream
+    // and upstream connection read/write buffering and back pressure, while this field sets the
+    // maximum size of an individual request body that Envoy may buffer for HTTP processing.
+    //
+    // For HTTP/1, connection buffer limits can still affect how request body data is read and buffered
+    // before or while the request body limit is enforced. Configure connection buffer limits large
+    // enough for the request body buffering you expect to allow on those connections.
+    //
+    // For HTTP/2, initial stream and connection window sizes control HTTP/2 flow control: how much data
+    // can be in flight before back pressure applies. They affect upload throughput and buffering
+    // behavior, but they are not a replacement for this request body size limit.
 	//
 	// If exceeded, the request will be rejected with HTTP 413 Content Too Large.
 	//

charts/gateway-crds-helm/templates/generated/gateway.envoyproxy.io_backendtrafficpolicies.yaml

@@ -2111,6 +2111,19 @@ spec:
                   RequestBodyBufferLimit specifies the maximum size in bytes that Envoy may buffer for request bodies.
                   This configures Envoy's request body buffer limit without enabling full request buffering.
 
+                  This Request body buffer limit is independent of the connection buffer limits configured by
+                  ClientTrafficPolicy and BackendTrafficPolicy. The connection buffer limits control downstream
+                  and upstream connection read/write buffering and back pressure, while this field sets the
+                  maximum size of an individual request body that Envoy may buffer for HTTP processing.
+
+                  For HTTP/1, connection buffer limits can still affect how request body data is read and buffered
+                  before or while the request body limit is enforced. Configure connection buffer limits large
+                  enough for the request body buffering you expect to allow on those connections.
+
+                  For HTTP/2, initial stream and connection window sizes control HTTP/2 flow control: how much data
+                  can be in flight before back pressure applies. They affect upload throughput and buffering
+                  behavior, but they are not a replacement for this request body size limit.
+
                   If exceeded, the request will be rejected with HTTP 413 Content Too Large.
 
                   Accepts values in resource.Quantity format (e.g., "10Mi", "500Ki").

charts/gateway-helm/charts/crds/crds/generated/gateway.envoyproxy.io_backendtrafficpolicies.yaml

@@ -2110,6 +2110,19 @@ spec:
                   RequestBodyBufferLimit specifies the maximum size in bytes that Envoy may buffer for request bodies.
                   This configures Envoy's request body buffer limit without enabling full request buffering.
 
+                  This Request body buffer limit is independent of the connection buffer limits configured by
+                  ClientTrafficPolicy and BackendTrafficPolicy. The connection buffer limits control downstream
+                  and upstream connection read/write buffering and back pressure, while this field sets the
+                  maximum size of an individual request body that Envoy may buffer for HTTP processing.
+
+                  For HTTP/1, connection buffer limits can still affect how request body data is read and buffered
+                  before or while the request body limit is enforced. Configure connection buffer limits large
+                  enough for the request body buffering you expect to allow on those connections.
+
+                  For HTTP/2, initial stream and connection window sizes control HTTP/2 flow control: how much data
+                  can be in flight before back pressure applies. They affect upload throughput and buffering
+                  behavior, but they are not a replacement for this request body size limit.
+
                   If exceeded, the request will be rejected with HTTP 413 Content Too Large.
 
                   Accepts values in resource.Quantity format (e.g., "10Mi", "500Ki").

release-notes/current.yaml

@@ -51,7 +51,6 @@ new features: |
   Added `source` field to `responseOverride` rules in BackendTrafficPolicy, allowing rules to target only Envoy-generated responses (`Local`), only upstream responses (`Backend`), or both (`All`, the default). This enables overriding envoy responses (e.g. auth/rate-limit failures) without affecting legitimate upstream responses with the same status code.
   Added support for path override in ExtAuth HTTP service.
   Added support for bandwidth limit.
-  Added BackendTrafficPolicy API support for configuring route-level request body buffer limits separately from full request buffering.
   Added support for defining Envoy Proxy image, pullPolicy, and pullSecrets via the helm chart.  Note that to merge these helm-configured values with EnvoyProxy resources, the EnvoyProxy must include `mergeType: StrategicMerge` or `mergeType: JSONMerge`.
 
 bug fixes: |

test/helm/gateway-crds-helm/all.out.yaml

@@ -24638,6 +24638,19 @@ spec:
                   RequestBodyBufferLimit specifies the maximum size in bytes that Envoy may buffer for request bodies.
                   This configures Envoy's request body buffer limit without enabling full request buffering.
 
+                  This Request body buffer limit is independent of the connection buffer limits configured by
+                  ClientTrafficPolicy and BackendTrafficPolicy. The connection buffer limits control downstream
+                  and upstream connection read/write buffering and back pressure, while this field sets the
+                  maximum size of an individual request body that Envoy may buffer for HTTP processing.
+
+                  For HTTP/1, connection buffer limits can still affect how request body data is read and buffered
+                  before or while the request body limit is enforced. Configure connection buffer limits large
+                  enough for the request body buffering you expect to allow on those connections.
+
+                  For HTTP/2, initial stream and connection window sizes control HTTP/2 flow control: how much data
+                  can be in flight before back pressure applies. They affect upload throughput and buffering
+                  behavior, but they are not a replacement for this request body size limit.
+
                   If exceeded, the request will be rejected with HTTP 413 Content Too Large.
 
                   Accepts values in resource.Quantity format (e.g., "10Mi", "500Ki").

test/helm/gateway-crds-helm/e2e.out.yaml

@@ -2611,6 +2611,19 @@ spec:
                   RequestBodyBufferLimit specifies the maximum size in bytes that Envoy may buffer for request bodies.
                   This configures Envoy's request body buffer limit without enabling full request buffering.
 
+                  This Request body buffer limit is independent of the connection buffer limits configured by
+                  ClientTrafficPolicy and BackendTrafficPolicy. The connection buffer limits control downstream
+                  and upstream connection read/write buffering and back pressure, while this field sets the
+                  maximum size of an individual request body that Envoy may buffer for HTTP processing.
+
+                  For HTTP/1, connection buffer limits can still affect how request body data is read and buffered
+                  before or while the request body limit is enforced. Configure connection buffer limits large
+                  enough for the request body buffering you expect to allow on those connections.
+
+                  For HTTP/2, initial stream and connection window sizes control HTTP/2 flow control: how much data
+                  can be in flight before back pressure applies. They affect upload throughput and buffering
+                  behavior, but they are not a replacement for this request body size limit.
+
                   If exceeded, the request will be rejected with HTTP 413 Content Too Large.
 
                   Accepts values in resource.Quantity format (e.g., "10Mi", "500Ki").

test/helm/gateway-crds-helm/envoy-gateway-crds.out.yaml

@@ -2611,6 +2611,19 @@ spec:
                   RequestBodyBufferLimit specifies the maximum size in bytes that Envoy may buffer for request bodies.
                   This configures Envoy's request body buffer limit without enabling full request buffering.
 
+                  This Request body buffer limit is independent of the connection buffer limits configured by
+                  ClientTrafficPolicy and BackendTrafficPolicy. The connection buffer limits control downstream
+                  and upstream connection read/write buffering and back pressure, while this field sets the
+                  maximum size of an individual request body that Envoy may buffer for HTTP processing.
+
+                  For HTTP/1, connection buffer limits can still affect how request body data is read and buffered
+                  before or while the request body limit is enforced. Configure connection buffer limits large
+                  enough for the request body buffering you expect to allow on those connections.
+
+                  For HTTP/2, initial stream and connection window sizes control HTTP/2 flow control: how much data
+                  can be in flight before back pressure applies. They affect upload throughput and buffering
+                  behavior, but they are not a replacement for this request body size limit.
+
                   If exceeded, the request will be rejected with HTTP 413 Content Too Large.
 
                   Accepts values in resource.Quantity format (e.g., "10Mi", "500Ki").