Skeleton of a tracer for AWS X-Ray (#8526)

A skeleton tracer to incrementally add support for AWS X-Ray

Risk Level: Low
Testing: unit tests for functionality in util - the rest of files have no business logic to test yet

Signed-off-by: Marco Magdy <mmagdy@gmail.com>

Mirrored from https://github.com/envoyproxy/envoy @ f68368f1a497d8f9254a714c2694cee88477438d

envoy/config/trace/v2/trace.proto

@@ -6,6 +6,7 @@ option java_outer_classname = "TraceProto";
 option java_multiple_files = true;
 option java_package = "io.envoyproxy.envoy.config.trace.v2";
 
+import "envoy/api/v2/core/base.proto";
 import "envoy/api/v2/core/grpc_service.proto";
 
 import "google/protobuf/any.proto";
@@ -34,6 +35,7 @@ message Tracing {
     // - *envoy.dynamic.ot*
     // - *envoy.tracers.datadog*
     // - *envoy.tracers.opencensus*
+    // - *envoy.tracers.xray*
     string name = 1 [(validate.rules).string = {min_bytes: 1}];
 
     // Trace driver specific configuration which depends on the driver being instantiated.
@@ -44,6 +46,8 @@ message Tracing {
     // - :ref:`DynamicOtConfig <envoy_api_msg_config.trace.v2.DynamicOtConfig>`
     // - :ref:`DatadogConfig <envoy_api_msg_config.trace.v2.DatadogConfig>`
     // - :ref:`OpenCensusConfig <envoy_api_msg_config.trace.v2.OpenCensusConfig>`
+    // [#comment: TODO(marco) when XRay is implemented, uncomment the following; - :ref:`XRayConfig
+    // <envoy_api_msg_config.trace.v2.XRayConfig>`]
     oneof config_type {
       google.protobuf.Struct config = 2;
 
@@ -199,6 +203,20 @@ message OpenCensusConfig {
   repeated TraceContext outgoing_trace_context = 9;
 }
 
+// [#not-implemented-hide:]
+// Configuration for AWS X-Ray tracer.
+message XRayConfig {
+  // The endpoint of the X-Ray Daemon where the spans will be sent. Since by default daemon
+  // listens to localhost:2000, so the default value is 127.0.0.1:2000.
+  string daemon_endpoint = 1 [(validate.rules).string = {min_bytes: 1}];
+
+  // The custom name to name a X-Ray segment. By default will use cluster name.
+  string segment_name = 2;
+
+  // The location of custom sampling rule json file.
+  api.v2.core.DataSource sampling_rule_manifest = 3;
+}
+
 // Configuration structure.
 message TraceServiceConfig {
   // The upstream gRPC cluster that hosts the metrics service.

envoy/config/trace/v3alpha/trace.proto

@@ -6,6 +6,7 @@ option java_outer_classname = "TraceProto";
 option java_multiple_files = true;
 option java_package = "io.envoyproxy.envoy.config.trace.v3alpha";
 
+import "envoy/api/v3alpha/core/base.proto";
 import "envoy/api/v3alpha/core/grpc_service.proto";
 
 import "google/protobuf/any.proto";
@@ -34,6 +35,7 @@ message Tracing {
     // - *envoy.dynamic.ot*
     // - *envoy.tracers.datadog*
     // - *envoy.tracers.opencensus*
+    // - *envoy.tracers.xray*
     string name = 1 [(validate.rules).string = {min_bytes: 1}];
 
     // Trace driver specific configuration which depends on the driver being instantiated.
@@ -44,6 +46,8 @@ message Tracing {
     // - :ref:`DynamicOtConfig <envoy_api_msg_config.trace.v3alpha.DynamicOtConfig>`
     // - :ref:`DatadogConfig <envoy_api_msg_config.trace.v3alpha.DatadogConfig>`
     // - :ref:`OpenCensusConfig <envoy_api_msg_config.trace.v3alpha.OpenCensusConfig>`
+    // [#comment: TODO(marco) when XRay is implemented, uncomment the following; - :ref:`XRayConfig
+    // <envoy_api_msg_config.trace.v3alpha.XRayConfig>`]
     oneof config_type {
       google.protobuf.Struct config = 2;
 
@@ -199,6 +203,20 @@ message OpenCensusConfig {
   repeated TraceContext outgoing_trace_context = 9;
 }
 
+// [#not-implemented-hide:]
+// Configuration for AWS X-Ray tracer.
+message XRayConfig {
+  // The endpoint of the X-Ray Daemon where the spans will be sent. Since by default daemon
+  // listens to localhost:2000, so the default value is 127.0.0.1:2000.
+  string daemon_endpoint = 1 [(validate.rules).string = {min_bytes: 1}];
+
+  // The custom name to name a X-Ray segment. By default will use cluster name.
+  string segment_name = 2;
+
+  // The location of custom sampling rule json file.
+  api.v3alpha.core.DataSource sampling_rule_manifest = 3;
+}
+
 // Configuration structure.
 message TraceServiceConfig {
   // The upstream gRPC cluster that hosts the metrics service.