add Decision enum

sdk/include/opentelemetry/sdk/trace/sampler.h

@@ -1,6 +1,8 @@
 #pragma once
 
 #include "opentelemetry/common/attribute_value.h"
+#include "opentelemetry/nostd/string_view.h"
+#include "opentelemetry/sdk/common/atomic_shared_ptr.h"
 #include "opentelemetry/trace/span.h"
 #include "opentelemetry/trace/trace_id.h"
 #include "opentelemetry/trace/tracer.h"
@@ -18,26 +20,33 @@ namespace trace
 namespace trace_api = opentelemetry::trace;
 class Sampler
 {
+private:
+  // Placeholder
+  class SpanContext
+  {};
+
 public:
   virtual ~Sampler() = default;
   /**
    * Called during Span creation to make a sampling decision.
    *
-   * @param parentContext TODO: the parent span's SpanContext. null if this is a root
+   * @param parent_context TODO: the parent span's SpanContext. null if this is a root
    *     span.
    * @param traceId the TraceId for the new Span. This will be identical to that in
    *     the parentContext, unless this is a root span.
    * @param name the name of the new Span.
    * @param parentLinks TODO: the parentLinks associated with the new Span.
    * @param spanKind the trace_api::SpanKind of the Span.
-   * @param attributes list of AttributeValue with their keys.
+   * @param attributes TODO: current map is a placeholder.
+   *     list of AttributeValue with their keys.
    * @return sampling decision whether span should be sampled or not.
    * @since 0.1.0
    */
 
   virtual SamplingResult ShouldSample(
+      std::shared_ptr<SpanContext> parent_context,
       trace_api::TraceId trace_id,
-      std::string name,
+      nostd::string_view name,
       trace_api::SpanKind span_kind,
       std::map<std::string, common::AttributeValue> attributes) noexcept = 0;
 
@@ -54,6 +63,14 @@ class Sampler
 
 class SamplingResult
 {
+private:
+  enum Decision
+  {
+    NOT_RECORD,
+    RECORD,
+    RECORD_AND_SAMPLE
+  };
+
 public:
   // TODO: add Decision enum
   virtual ~SamplingResult() = default;
@@ -62,15 +79,16 @@ class SamplingResult
    *
    * @return TODO: Decision.
    */
-  virtual bool GetDecision();
+  virtual Decision GetDecision() const noexcept = 0;
 
   /**
    * Return attributes which will be attached to the span.
    *
+   * TODO: Change return value to nostd::span<std::pair<nostd::string_view, common::AttributeValue>>
    * @return attributes added to span. These attributes should be added to the span only for root
    *     span or when sampling decision isSampled() changes from false to true.
    */
-  virtual std::map<std::string, common::AttributeValue> GetAttributes();
+  virtual std::map<std::string, common::AttributeValue> GetAttributes() const noexcept = 0;
 };
 }  // namespace trace
 }  // namespace sdk