1 files changed, 132 insertions, 0 deletions
diff --git a/src/cpp/ext/filters/census/context.cc b/src/cpp/ext/filters/census/context.cc
new file mode 100644
index 0000000000..4b3250236d
--- /dev/null
+++ b/src/cpp/ext/filters/census/context.cc
@@ -0,0 +1,132 @@
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+#include <grpc/support/port_platform.h>
+
+#include "src/cpp/ext/filters/census/context.h"
+
+namespace grpc {
+
+using ::opencensus::trace::Span;
+using ::opencensus::trace::SpanContext;
+
+void GenerateServerContext(absl::string_view tracing, absl::string_view stats,
+                           absl::string_view primary_role,
+                           absl::string_view method, CensusContext* context) {
+  GrpcTraceContext trace_ctxt;
+  TraceContextEncoding::Decode(tracing, &trace_ctxt);
+  SpanContext parent_ctx = trace_ctxt.ToSpanContext();
+  new (context) CensusContext(method, parent_ctx);
+}
+
+void GenerateClientContext(absl::string_view method, CensusContext* ctxt,
+                           CensusContext* parent_ctxt) {
+  if (parent_ctxt != nullptr) {
+    SpanContext span_ctxt = parent_ctxt->Context();
+    Span span = parent_ctxt->Span();
+    if (span_ctxt.IsValid()) {
+      new (ctxt) CensusContext(method, &span);
+      return;
+    }
+  }
+  new (ctxt) CensusContext(method);
+}
+
+size_t TraceContextSerialize(const ::opencensus::trace::SpanContext& context,
+                             char* tracing_buf, size_t tracing_buf_size) {
+  GrpcTraceContext trace_ctxt(context);
+  return TraceContextEncoding::Encode(trace_ctxt, tracing_buf,
+                                      tracing_buf_size);
+}
+
+size_t StatsContextSerialize(size_t max_tags_len, grpc_slice* tags) {
+  // TODO: Add implementation. Waiting on stats tagging to be added.
+  return 0;
+}
+
+size_t ServerStatsSerialize(uint64_t server_elapsed_time, char* buf,
+                            size_t buf_size) {
+  return RpcServerStatsEncoding::Encode(server_elapsed_time, buf, buf_size);
+}
+
+size_t ServerStatsDeserialize(const char* buf, size_t buf_size,
+                              uint64_t* server_elapsed_time) {
+  return RpcServerStatsEncoding::Decode(absl::string_view(buf, buf_size),
+                                        server_elapsed_time);
+}
+
+uint64_t GetIncomingDataSize(const grpc_call_final_info* final_info) {
+  return final_info->stats.transport_stream_stats.incoming.data_bytes;
+}
+
+uint64_t GetOutgoingDataSize(const grpc_call_final_info* final_info) {
+  return final_info->stats.transport_stream_stats.outgoing.data_bytes;
+}
+
+SpanContext SpanContextFromCensusContext(const census_context* ctxt) {
+  return reinterpret_cast<const CensusContext*>(ctxt)->Context();
+}
+
+Span SpanFromCensusContext(const census_context* ctxt) {
+  return reinterpret_cast<const CensusContext*>(ctxt)->Span();
+}
+
+absl::string_view StatusCodeToString(grpc_status_code code) {
+  switch (code) {
+    case GRPC_STATUS_OK:
+      return "OK";
+    case GRPC_STATUS_CANCELLED:
+      return "CANCELLED";
+    case GRPC_STATUS_UNKNOWN:
+      return "UNKNOWN";
+    case GRPC_STATUS_INVALID_ARGUMENT:
+      return "INVALID_ARGUMENT";
+    case GRPC_STATUS_DEADLINE_EXCEEDED:
+      return "DEADLINE_EXCEEDED";
+    case GRPC_STATUS_NOT_FOUND:
+      return "NOT_FOUND";
+    case GRPC_STATUS_ALREADY_EXISTS:
+      return "ALREADY_EXISTS";
+    case GRPC_STATUS_PERMISSION_DENIED:
+      return "PERMISSION_DENIED";
+    case GRPC_STATUS_UNAUTHENTICATED:
+      return "UNAUTHENTICATED";
+    case GRPC_STATUS_RESOURCE_EXHAUSTED:
+      return "RESOURCE_EXHAUSTED";
+    case GRPC_STATUS_FAILED_PRECONDITION:
+      return "FAILED_PRECONDITION";
+    case GRPC_STATUS_ABORTED:
+      return "ABORTED";
+    case GRPC_STATUS_OUT_OF_RANGE:
+      return "OUT_OF_RANGE";
+    case GRPC_STATUS_UNIMPLEMENTED:
+      return "UNIMPLEMENTED";
+    case GRPC_STATUS_INTERNAL:
+      return "INTERNAL";
+    case GRPC_STATUS_UNAVAILABLE:
+      return "UNAVAILABLE";
+    case GRPC_STATUS_DATA_LOSS:
+      return "DATA_LOSS";
+    default:
+      // gRPC wants users of this enum to include a default branch so that
+      // adding values is not a breaking change.
+      return "UNKNOWN_STATUS";
+  }
+}
+
+}  // namespace grpc