Added OTEL access logging envoy extension

.changelog/18336.txt

@@ -0,0 +1,7 @@
+```release-note:feature
+xds: Add a built-in Envoy extension that appends OpenTelemetry Access Logging (otel-access-logging) to the HTTP Connection Manager filter.
+```
+
+```release-note:feature
+xds: Add support for patching outbound listeners to the built-in Envoy External Authorization extension.
+```

agent/envoyextensions/builtin/ext-authz/ext_authz.go

@@ -23,6 +23,8 @@ type extAuthz struct {
 	ProxyType api.ServiceKind
 	// InsertOptions controls how the extension inserts the filter.
 	InsertOptions ext_cmn.InsertOptions
+	// ListenerType controls which listener the extension applies to. It supports "inbound" or "outbound" listeners.
+	ListenerType string
 	// Config holds the extension configuration.
 	Config extAuthzConfig
 }
@@ -61,10 +63,14 @@ func (a *extAuthz) PatchClusters(cfg *ext_cmn.RuntimeConfig, c ext_cmn.ClusterMa
 	return c, nil
 }
 
+func (a *extAuthz) matchesListenerDirection(isInboundListener bool) bool {
+	return (!isInboundListener && a.ListenerType == "outbound") || (isInboundListener && a.ListenerType == "inbound")
+}
+
 // PatchFilters inserts an ext-authz filter into the list of network filters or the filter chain of the HTTP connection manager.
 func (a *extAuthz) PatchFilters(cfg *ext_cmn.RuntimeConfig, filters []*envoy_listener_v3.Filter, isInboundListener bool) ([]*envoy_listener_v3.Filter, error) {
 	// The ext_authz extension only patches filters for inbound listeners.
-	if !isInboundListener {
+	if !a.matchesListenerDirection(isInboundListener) {
 		return filters, nil
 	}
 
@@ -129,6 +135,11 @@ func (a *extAuthz) normalize() {
 	if a.ProxyType == "" {
 		a.ProxyType = api.ServiceKindConnectProxy
 	}
+
+	if a.ListenerType == "" {
+		a.ListenerType = "inbound"
+	}
+
 	a.Config.normalize()
 }
 
@@ -140,6 +151,10 @@ func (a *extAuthz) validate() error {
 			api.ServiceKindConnectProxy))
 	}
 
+	if a.ListenerType != "inbound" && a.ListenerType != "outbound" {
+		resultErr = multierror.Append(resultErr, fmt.Errorf(`unexpected ListenerType %q, supported values are "inbound" or "outbound"`, a.ListenerType))
+	}
+
 	if err := a.Config.validate(); err != nil {
 		resultErr = multierror.Append(resultErr, err)
 	}

agent/envoyextensions/builtin/otel-access-logging/otel_access_logging.go

@@ -0,0 +1,280 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
+package otelaccesslogging
+
+import (
+	"fmt"
+
+	envoy_extensions_access_loggers_v3 "github.com/envoyproxy/go-control-plane/envoy/config/accesslog/v3"
+	envoy_listener_v3 "github.com/envoyproxy/go-control-plane/envoy/config/listener/v3"
+	envoy_extensions_access_loggers_otel_v3 "github.com/envoyproxy/go-control-plane/envoy/extensions/access_loggers/open_telemetry/v3"
+	"github.com/mitchellh/mapstructure"
+	"google.golang.org/protobuf/proto"
+	"google.golang.org/protobuf/types/known/anypb"
+
+	"github.com/hashicorp/consul/api"
+	"github.com/hashicorp/consul/envoyextensions/extensioncommon"
+	cmn "github.com/hashicorp/consul/envoyextensions/extensioncommon"
+	ext_cmn "github.com/hashicorp/consul/envoyextensions/extensioncommon"
+	"github.com/hashicorp/go-multierror"
+	v1 "go.opentelemetry.io/proto/otlp/common/v1"
+)
+
+type otelAccessLogging struct {
+	ext_cmn.BasicExtensionAdapter
+
+	// ProxyType identifies the type of Envoy proxy that this extension applies to.
+	// The extension will only be configured for proxies that match this type and
+	// will be ignored for all other proxy types.
+	ProxyType api.ServiceKind
+	// InsertOptions controls how the extension inserts the filter.
+	InsertOptions ext_cmn.InsertOptions
+	// ListenerType controls which listener the extension applies to. It supports "inbound" or "outbound" listeners.
+	ListenerType string
+	// Config holds the extension configuration.
+	Config AccessLog
+}
+
+var _ ext_cmn.BasicExtension = (*otelAccessLogging)(nil)
+
+func Constructor(ext api.EnvoyExtension) (ext_cmn.EnvoyExtender, error) {
+	otel, err := newOTELAccessLogging(ext)
+	if err != nil {
+		return nil, err
+	}
+	return &ext_cmn.BasicEnvoyExtender{
+		Extension: otel,
+	}, nil
+}
+
+// CanApply indicates if the extension can be applied to the given extension runtime configuration.
+func (a *otelAccessLogging) CanApply(config *ext_cmn.RuntimeConfig) bool {
+	return config.Kind == api.ServiceKindConnectProxy
+}
+
+// PatchClusters modifies the cluster resources for the extension.
+//
+// If the extension is configured to target the OTEL service running on the local host network
+// this func will insert a cluster for calling that service. It does nothing if the extension is
+// configured to target an upstream service because the existing cluster for the upstream will be
+// used directly by the filter.
+func (a *otelAccessLogging) PatchClusters(cfg *ext_cmn.RuntimeConfig, c ext_cmn.ClusterMap) (ext_cmn.ClusterMap, error) {
+	cluster, err := a.Config.toEnvoyCluster(cfg)
+	if err != nil {
+		return c, err
+	}
+	if cluster != nil {
+		c[cluster.Name] = cluster
+	}
+	return c, nil
+}
+
+func (a *otelAccessLogging) matchesListenerDirection(p extensioncommon.FilterPayload) bool {
+	isInboundListener := p.IsInbound()
+	return (!isInboundListener && a.ListenerType == "outbound") || (isInboundListener && a.ListenerType == "inbound")
+}
+
+// PatchFilter adds the OTEL access log in the HTTP connection manager.
+func (a *otelAccessLogging) PatchFilter(p ext_cmn.FilterPayload) (*envoy_listener_v3.Filter, bool, error) {
+	filter := p.Message
+	// Make sure filter matches extension config.
+	if !a.matchesListenerDirection(p) {
+		return filter, false, nil
+	}
+
+	httpConnectionManager, _, err := ext_cmn.GetHTTPConnectionManager(filter)
+	if err != nil {
+		return filter, false, nil
+	}
+
+	accessLog, err := a.toEnvoyAccessLog(p.RuntimeConfig)
+	if err != nil {
+		return filter, false, err
+	}
+
+	httpConnectionManager.AccessLog = append(httpConnectionManager.AccessLog, accessLog)
+	newHCM, err := ext_cmn.MakeFilter("envoy.filters.network.http_connection_manager", httpConnectionManager)
+	if err != nil {
+		return filter, false, err
+	}
+
+	return newHCM, true, nil
+}
+
+func newOTELAccessLogging(ext api.EnvoyExtension) (*otelAccessLogging, error) {
+	otel := &otelAccessLogging{}
+	if ext.Name != api.BuiltinOTELAccessLoggingExtension {
+		return otel, fmt.Errorf("expected extension name %q but got %q", api.BuiltinOTELAccessLoggingExtension, ext.Name)
+	}
+	if err := otel.fromArguments(ext.Arguments); err != nil {
+		return otel, err
+	}
+
+	return otel, nil
+}
+
+func (a *otelAccessLogging) fromArguments(args map[string]any) error {
+	if err := mapstructure.Decode(args, a); err != nil {
+		return err
+	}
+	if err := a.normalize(); err != nil {
+		return err
+	}
+	return a.validate()
+}
+
+func (a *otelAccessLogging) toEnvoyAccessLog(cfg *cmn.RuntimeConfig) (*envoy_extensions_access_loggers_v3.AccessLog, error) {
+	commonConfig, err := a.Config.toEnvoyCommonGrpcAccessLogConfig(cfg)
+	if err != nil {
+		return nil, err
+	}
+
+	body, err := toEnvoyAnyValue(a.Config.Body)
+	if err != nil {
+		return nil, fmt.Errorf("failed to marshal Body: %w", err)
+	}
+
+	attributes, err := toEnvoyKeyValueList(a.Config.Attributes)
+	if err != nil {
+		return nil, fmt.Errorf("failed to marshal Attributes: %w", err)
+	}
+
+	resourceAttributes, err := toEnvoyKeyValueList(a.Config.ResourceAttributes)
+	if err != nil {
+		return nil, fmt.Errorf("failed to marshal ResourceAttributes: %w", err)
+	}
+
+	otelAccessLogConfig := &envoy_extensions_access_loggers_otel_v3.OpenTelemetryAccessLogConfig{
+		CommonConfig:       commonConfig,
+		Body:               body,
+		Attributes:         attributes,
+		ResourceAttributes: resourceAttributes,
+	}
+
+	// Marshal the struct to bytes.
+	otelAccessLogConfigBytes, err := proto.Marshal(otelAccessLogConfig)
+	if err != nil {
+		return nil, fmt.Errorf("failed to marshal OpenTelemetryAccessLogConfig: %w", err)
+	}
+
+	return &envoy_extensions_access_loggers_v3.AccessLog{
+		Name: "envoy.access_loggers.open_telemetry",
+		ConfigType: &envoy_extensions_access_loggers_v3.AccessLog_TypedConfig{
+			TypedConfig: &anypb.Any{
+				Value:   otelAccessLogConfigBytes,
+				TypeUrl: "type.googleapis.com/envoy.extensions.access_loggers.open_telemetry.v3.OpenTelemetryAccessLogConfig",
+			},
+		},
+	}, nil
+}
+
+func (a *otelAccessLogging) normalize() error {
+	if a.ProxyType == "" {
+		a.ProxyType = api.ServiceKindConnectProxy
+	}
+
+	if a.ListenerType == "" {
+		a.ListenerType = "inbound"
+	}
+
+	if a.Config.LogName == "" {
+		a.Config.LogName = a.ListenerType
+	}
+
+	return a.Config.normalize()
+}
+
+func (a *otelAccessLogging) validate() error {
+	var resultErr error
+	if a.ProxyType != api.ServiceKindConnectProxy {
+		resultErr = multierror.Append(resultErr, fmt.Errorf("unsupported ProxyType %q, only %q is supported",
+			a.ProxyType,
+			api.ServiceKindConnectProxy))
+	}
+
+	if a.ListenerType != "inbound" && a.ListenerType != "outbound" {
+		resultErr = multierror.Append(resultErr, fmt.Errorf(`unexpected ListenerType %q, supported values are "inbound" or "outbound"`, a.ListenerType))
+	}
+
+	if err := a.Config.validate(); err != nil {
+		resultErr = multierror.Append(resultErr, err)
+	}
+
+	return resultErr
+}
+
+func toEnvoyKeyValueList(attributes map[string]any) (*v1.KeyValueList, error) {
+	keyValueList := &v1.KeyValueList{}
+	for key, value := range attributes {
+		anyValue, err := toEnvoyAnyValue(value)
+		if err != nil {
+			return nil, err
+		}
+		keyValueList.Values = append(keyValueList.Values, &v1.KeyValue{
+			Key:   key,
+			Value: anyValue,
+		})
+	}
+
+	return keyValueList, nil
+}
+
+func toEnvoyAnyValue(value interface{}) (*v1.AnyValue, error) {
+	if value == nil {
+		return nil, nil
+	}
+
+	switch v := value.(type) {
+	case string:
+		return &v1.AnyValue{
+			Value: &v1.AnyValue_StringValue{
+				StringValue: v,
+			},
+		}, nil
+	case int:
+		return &v1.AnyValue{
+			Value: &v1.AnyValue_IntValue{
+				IntValue: int64(v),
+			},
+		}, nil
+	case int32:
+		return &v1.AnyValue{
+			Value: &v1.AnyValue_IntValue{
+				IntValue: int64(v),
+			},
+		}, nil
+	case int64:
+		return &v1.AnyValue{
+			Value: &v1.AnyValue_IntValue{
+				IntValue: v,
+			},
+		}, nil
+	case float32:
+		return &v1.AnyValue{
+			Value: &v1.AnyValue_DoubleValue{
+				DoubleValue: float64(v),
+			},
+		}, nil
+	case float64:
+		return &v1.AnyValue{
+			Value: &v1.AnyValue_DoubleValue{
+				DoubleValue: v,
+			},
+		}, nil
+	case bool:
+		return &v1.AnyValue{
+			Value: &v1.AnyValue_BoolValue{
+				BoolValue: v,
+			},
+		}, nil
+	case []byte:
+		return &v1.AnyValue{
+			Value: &v1.AnyValue_BytesValue{
+				BytesValue: v,
+			},
+		}, nil
+	default:
+		return nil, fmt.Errorf("unsupported type %T", v)
+	}
+}