server: introduce ServerMetricRecorder API and move per-call reporting from a C++ interceptor to a C-core filter

.gitattributes

@@ -29,5 +29,8 @@ tools/run_tests/tests.json linguist-generated=true
 tools/run_tests/generated/tests.json linguist-generated=true
 tools/run_tests/generated/sources_and_headers.json linguist-generated=true
 src/core/lib/security/credentials/tls/grpc_tls_credentials_options.h linguist-generated=true
-src/core/lib/transport/static_metadata.h linguist-generated=true
-src/core/lib/transport/static_metadata.cc linguist-generated=true
+src/core/debug/stats_data.h linguist-generated=true
+src/core/debug/stats_data.cc linguist-generated=true
+src/core/experiments/experiments.h linguist-generated=true
+src/core/experiments/experiments.cc linguist-generated=true
+bazel/experiments.bzl linguist-generated=true

BUILD

@@ -753,6 +753,7 @@ grpc_cc_library(
         "//src/core:grpc_lb_policy_priority",
         "//src/core:grpc_lb_policy_ring_hash",
         "//src/core:grpc_lb_policy_round_robin",
+        "//src/core:grpc_lb_policy_weighted_round_robin",
         "//src/core:grpc_lb_policy_weighted_target",
         "//src/core:grpc_channel_idle_filter",
         "//src/core:grpc_message_size_filter",
@@ -1174,7 +1175,6 @@ grpc_cc_library(
 grpc_cc_library(
     name = "grpc_base",
     srcs = [
-        "//src/core:lib/address_utils/parse_address.cc",
         "//src/core:lib/channel/channel_stack.cc",
         "//src/core:lib/channel/channel_stack_builder_impl.cc",
         "//src/core:lib/channel/channel_trace.cc",
@@ -1205,8 +1205,6 @@ grpc_cc_library(
         "//src/core:lib/iomgr/gethostname_fallback.cc",
         "//src/core:lib/iomgr/gethostname_host_name_max.cc",
         "//src/core:lib/iomgr/gethostname_sysconf.cc",
-        "//src/core:lib/iomgr/grpc_if_nametoindex_posix.cc",
-        "//src/core:lib/iomgr/grpc_if_nametoindex_unsupported.cc",
         "//src/core:lib/iomgr/internal_errqueue.cc",
         "//src/core:lib/iomgr/iocp_windows.cc",
         "//src/core:lib/iomgr/iomgr.cc",
@@ -1274,9 +1272,15 @@ grpc_cc_library(
         "//src/core:lib/transport/timeout_encoding.cc",
         "//src/core:lib/transport/transport.cc",
         "//src/core:lib/transport/transport_op_string.cc",
+    ] +
+    # TODO(vigneshbabu): remove these
+    # These headers used to be vended by this target, but they have to be
+    # removed after landing event engine.
+    [
+        "//src/core:lib/iomgr/event_engine_shims/endpoint.cc",
+        "//src/core:lib/iomgr/event_engine_shims/tcp_client.cc",
     ],
     hdrs = [
-        "//src/core:lib/address_utils/parse_address.h",
         "//src/core:lib/channel/call_finalization.h",
         "//src/core:lib/channel/call_tracer.h",
         "//src/core:lib/channel/channel_stack.h",
@@ -1304,7 +1308,6 @@ grpc_cc_library(
         "//src/core:lib/iomgr/ev_poll_posix.h",
         "//src/core:lib/iomgr/ev_posix.h",
         "//src/core:lib/iomgr/gethostname.h",
-        "//src/core:lib/iomgr/grpc_if_nametoindex.h",
         "//src/core:lib/iomgr/internal_errqueue.h",
         "//src/core:lib/iomgr/iocp_windows.h",
         "//src/core:lib/iomgr/iomgr.h",
@@ -1359,6 +1362,13 @@ grpc_cc_library(
         "//src/core:lib/transport/timeout_encoding.h",
         "//src/core:lib/transport/transport.h",
         "//src/core:lib/transport/transport_impl.h",
+    ] +
+    # TODO(vigneshbabu): remove these
+    # These headers used to be vended by this target, but they have to be
+    # removed after landing event engine.
+    [
+        "//src/core:lib/iomgr/event_engine_shims/endpoint.h",
+        "//src/core:lib/iomgr/event_engine_shims/tcp_client.h",
     ],
     defines = select({
         "systemd": ["HAVE_LIBSYSTEMD"],
@@ -1400,6 +1410,7 @@ grpc_cc_library(
         "grpc_trace",
         "iomgr_timer",
         "orphanable",
+        "parse_address",
         "promise",
         "ref_counted_ptr",
         "sockaddr_utils",
@@ -1423,6 +1434,10 @@ grpc_cc_library(
         "//src/core:default_event_engine",
         "//src/core:dual_ref_counted",
         "//src/core:error",
+        "//src/core:event_engine_common",
+        "//src/core:event_engine_shim",
+        "//src/core:event_engine_tcp_socket_utils",
+        "//src/core:event_engine_trace",
         "//src/core:event_log",
         "//src/core:experiments",
         "//src/core:gpr_atm",
@@ -1443,6 +1458,7 @@ grpc_cc_library(
         "//src/core:pipe",
         "//src/core:poll",
         "//src/core:pollset_set",
+        "//src/core:posix_event_engine_base_hdrs",
         "//src/core:promise_status",
         "//src/core:ref_counted",
         "//src/core:resolved_address",
@@ -1632,6 +1648,7 @@ grpc_cc_library(
         "handshaker",
         "promise",
         "ref_counted_ptr",
+        "stats",
         "tsi_base",
         "//src/core:activity",
         "//src/core:arena",
@@ -1655,6 +1672,7 @@ grpc_cc_library(
         "//src/core:seq",
         "//src/core:slice",
         "//src/core:slice_refcount",
+        "//src/core:stats_data",
         "//src/core:status_helper",
         "//src/core:try_seq",
         "//src/core:unique_type_name",
@@ -1783,7 +1801,7 @@ grpc_cc_library(
         "grpc_service_config_impl",
         "grpc_trace",
         "grpcpp_call_metric_recorder",
-        "grpcpp_server_metric_recorder",
+        "grpcpp_backend_metric_recorder",
         "grpcpp_status",
         "iomgr_timer",
         "ref_counted_ptr",
@@ -1853,7 +1871,7 @@ grpc_cc_library(
         "grpc_trace",
         "grpc_unsecure",
         "grpcpp_call_metric_recorder",
-        "grpcpp_server_metric_recorder",
+        "grpcpp_backend_metric_recorder",
         "grpcpp_status",
         "iomgr_timer",
         "ref_counted_ptr",
@@ -1962,9 +1980,12 @@ grpc_cc_library(
 )
 
 grpc_cc_library(
-    name = "grpcpp_server_metric_recorder",
+    name = "grpcpp_backend_metric_recorder",
     srcs = [
-        "src/cpp/server/orca/server_metric_recorder.cc",
+        "src/cpp/server/orca/backend_metric_recorder.cc",
+    ],
+    hdrs = [
+        "src/cpp/server/backend_metric_recorder.h"
     ],
     language = "c++",
     public_hdrs = [
@@ -1973,8 +1994,11 @@ grpc_cc_library(
     visibility = ["@grpc:public"],
     deps = [
         "gpr",
+        "grpcpp_call_metric_recorder",
+        "grpc++_public_hdrs",
         "grpc_trace",
         "//src/core:grpc_backend_metric_data",
+        "//src/core:grpc_backend_metric_provider",
     ],
 )
 
@@ -2000,7 +2024,7 @@ grpc_cc_library(
         "gpr",
         "grpc++",
         "grpc_base",
-        "grpcpp_server_metric_recorder",
+        "grpcpp_backend_metric_recorder",
         "protobuf_duration_upb",
         "ref_counted_ptr",
         "xds_orca_service_upb",
@@ -2170,6 +2194,7 @@ grpc_cc_library(
         "//src/core:channel_args",
         "//src/core:channel_stack_type",
         "//src/core:closure",
+        "//src/core:experiments",
         "//src/core:slice",
         "//src/core:slice_buffer",
         "//src/core:slice_refcount",
@@ -2484,6 +2509,34 @@ grpc_cc_library(
     deps = ["gpr"],
 )
 
+grpc_cc_library(
+    name = "parse_address",
+    srcs = [
+        "//src/core:lib/address_utils/parse_address.cc",
+        "//src/core:lib/iomgr/grpc_if_nametoindex_posix.cc",
+        "//src/core:lib/iomgr/grpc_if_nametoindex_unsupported.cc",
+    ],
+    hdrs = [
+        "//src/core:lib/address_utils/parse_address.h",
+        "//src/core:lib/iomgr/grpc_if_nametoindex.h",
+    ],
+    external_deps = [
+        "absl/status",
+        "absl/status:statusor",
+        "absl/strings",
+    ],
+    visibility = ["@grpc:alt_grpc_base_legacy"],
+    deps = [
+        "gpr",
+        "uri_parser",
+        "//src/core:error",
+        "//src/core:grpc_sockaddr",
+        "//src/core:iomgr_port",
+        "//src/core:resolved_address",
+        "//src/core:status_helper",
+    ],
+)
+
 grpc_cc_library(
     name = "backoff",
     srcs = [
@@ -2679,6 +2732,7 @@ grpc_cc_library(
         "//src/core:ext/filters/client_channel/lb_call_state_internal.h",
         "//src/core:ext/filters/client_channel/lb_policy/child_policy_handler.h",
         "//src/core:ext/filters/client_channel/lb_policy/oob_backend_metric.h",
+        "//src/core:ext/filters/client_channel/lb_policy/oob_backend_metric_internal.h",
         "//src/core:ext/filters/client_channel/local_subchannel_pool.h",
         "//src/core:ext/filters/client_channel/retry_filter.h",
         "//src/core:ext/filters/client_channel/retry_service_config.h",
@@ -2810,6 +2864,7 @@ grpc_cc_library(
         "grpc_trace",
         "iomgr_timer",
         "orphanable",
+        "parse_address",
         "ref_counted_ptr",
         "server_address",
         "sockaddr_utils",
@@ -3752,6 +3807,11 @@ grpc_upb_proto_library(
     deps = ["@envoy_api//envoy/type/http/v3:pkg"],
 )
 
+grpc_upb_proto_library(
+    name = "envoy_extensions_load_balancing_policies_client_side_weighted_round_robin_upb",
+    deps = ["@envoy_api//envoy/extensions/load_balancing_policies/client_side_weighted_round_robin/v3:pkg"],
+)
+
 grpc_upb_proto_library(
     name = "envoy_extensions_load_balancing_policies_ring_hash_upb",
     deps = ["@envoy_api//envoy/extensions/load_balancing_policies/ring_hash/v3:pkg"],