[dynamic control] Add SourceKind to TelemetryPolicy (open-telemetry#2972)

Author: jackshirazi

dynamic-control/src/main/java/io/opentelemetry/contrib/dynamic/policy/DeletedTelemetryPolicy.java

@@ -5,15 +5,24 @@
 
 package io.opentelemetry.contrib.dynamic.policy;
 
+import io.opentelemetry.contrib.dynamic.policy.source.SourceKind;
 import java.util.Objects;
 
 public final class DeletedTelemetryPolicy implements TelemetryPolicy {
   private final TelemetryPolicyIdentity identity;
   private final String type;
+  private final SourceKind sourceKind;
 
+  // TODO after "source" prioritization handling is complete, remove this constructor
   public DeletedTelemetryPolicy(TelemetryPolicyIdentity identity, String type) {
+    this(identity, type, SourceKind.CUSTOM);
+  }
+
+  public DeletedTelemetryPolicy(
+      TelemetryPolicyIdentity identity, String type, SourceKind sourceKind) {
     this.identity = Objects.requireNonNull(identity, "identity cannot be null");
     this.type = Objects.requireNonNull(type, "type cannot be null");
+    this.sourceKind = Objects.requireNonNull(sourceKind, "sourceKind cannot be null");
   }
 
   @Override
@@ -26,13 +35,24 @@ public String getType() {
     return type;
   }
 
+  @Override
+  public SourceKind getSourceKind() {
+    return sourceKind;
+  }
+
   @Override
   public boolean isDeleted() {
     return true;
   }
 
   @Override
   public String toString() {
-    return "DeletedTelemetryPolicy{identity=" + identity + ", type='" + getType() + "'}";
+    return "DeletedTelemetryPolicy{identity="
+        + identity
+        + ", type='"
+        + getType()
+        + "', sourceKind="
+        + sourceKind
+        + "}";
   }
 }

dynamic-control/src/main/java/io/opentelemetry/contrib/dynamic/policy/TelemetryPolicy.java

@@ -5,6 +5,8 @@
 
 package io.opentelemetry.contrib.dynamic.policy;
 
+import io.opentelemetry.contrib.dynamic.policy.source.SourceKind;
+
 /**
  * Represents a single telemetry policy with spec-required identity and policy type.
  *
@@ -35,6 +37,17 @@ public interface TelemetryPolicy {
    */
   String getType();
 
+  /**
+   * Returns the provider source kind that supplied this policy.
+   *
+   * <p>The source is used to resolve duplicate policy IDs across providers. Lower-priority sources
+   * are dropped when a higher-priority source supplies the same policy identity.
+   */
+  // TODO after "source" prioritization handling is complete, make non-default
+  default SourceKind getSourceKind() {
+    return SourceKind.CUSTOM;
+  }
+
   /**
    * Returns whether this policy represents a deleted element.
    *

dynamic-control/src/main/java/io/opentelemetry/contrib/dynamic/policy/tracesampling/TraceSamplingRatePolicy.java

@@ -9,6 +9,7 @@
 import io.opentelemetry.contrib.dynamic.policy.TelemetryPolicy;
 import io.opentelemetry.contrib.dynamic.policy.TelemetryPolicyIdentity;
 import io.opentelemetry.contrib.dynamic.policy.registry.PolicyInit;
+import io.opentelemetry.contrib.dynamic.policy.source.SourceKind;
 import io.opentelemetry.sdk.autoconfigure.spi.AutoConfigurationCustomizer;
 import io.opentelemetry.sdk.extension.incubator.trace.samplers.ComposableSampler;
 import io.opentelemetry.sdk.extension.incubator.trace.samplers.CompositeSampler;
@@ -25,10 +26,17 @@ public final class TraceSamplingRatePolicy implements TelemetryPolicy {
 
   private final TelemetryPolicyIdentity identity;
   private final double probability;
+  private final SourceKind sourceKind;
 
+  // TODO after "source" prioritization handling is complete, remove this constructor
   public TraceSamplingRatePolicy(double probability) {
+    this(probability, SourceKind.CUSTOM);
+  }
+
+  public TraceSamplingRatePolicy(double probability, SourceKind sourceKind) {
     this.identity = DEFAULT_IDENTITY;
     this.probability = normalizeProbability(probability);
+    this.sourceKind = Objects.requireNonNull(sourceKind, "sourceKind cannot be null");
   }
 
   @Override
@@ -41,6 +49,11 @@ public String getType() {
     return POLICY_TYPE;
   }
 
+  @Override
+  public SourceKind getSourceKind() {
+    return sourceKind;
+  }
+
   public double getProbability() {
     return probability;
   }