Use alwaysOn() sampler (#42)

* Use alwaysOn() sampler

* spotless

* fix failing smoke test

Author: Mateusz Rzeszutek

custom/src/main/java/com/splunk/opentelemetry/SplunkTracerCustomizer.java

@@ -18,6 +18,7 @@
 
 import io.opentelemetry.javaagent.spi.TracerCustomizer;
 import io.opentelemetry.sdk.trace.TracerSdkManagement;
+import io.opentelemetry.sdk.trace.samplers.Sampler;
 
 public class SplunkTracerCustomizer implements TracerCustomizer {
 
@@ -42,5 +43,8 @@ public void configure(TracerSdkManagement tracerManagement) {
     if (jdbcSpanLowCardinalityNameEnabled()) {
       tracerManagement.addSpanProcessor(new JdbcSpanRenamingProcessor());
     }
+
+    tracerManagement.updateActiveTraceConfig(
+        tracerManagement.getActiveTraceConfig().toBuilder().setSampler(Sampler.alwaysOn()).build());
   }
 }

custom/src/test/java/com/splunk/opentelemetry/SplunkTracerCustomizerTest.java

@@ -17,32 +17,46 @@
 package com.splunk.opentelemetry;
 
 import static com.splunk.opentelemetry.SplunkTracerCustomizer.ENABLE_JDBC_SPAN_LOW_CARDINALITY_NAME_PROPERTY;
+import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.mockito.ArgumentMatchers.isA;
+import static org.mockito.BDDMockito.given;
 import static org.mockito.BDDMockito.then;
 
 import io.opentelemetry.sdk.trace.TracerSdkProvider;
+import io.opentelemetry.sdk.trace.config.TraceConfig;
+import io.opentelemetry.sdk.trace.samplers.Sampler;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.ArgumentCaptor;
+import org.mockito.Captor;
 import org.mockito.Mock;
 import org.mockito.junit.jupiter.MockitoExtension;
 
 @ExtendWith(MockitoExtension.class)
 public class SplunkTracerCustomizerTest {
   @Mock private TracerSdkProvider tracerSdkProvider;
 
+  @Captor private ArgumentCaptor<TraceConfig> traceConfigCaptor;
+
   @Test
   public void shouldAddSpanProcessorsIfPropertiesAreSetToTrue() {
 
     // given
     SplunkTracerCustomizer underTest = new SplunkTracerCustomizer();
     System.setProperty(ENABLE_JDBC_SPAN_LOW_CARDINALITY_NAME_PROPERTY, "true");
 
+    TraceConfig traceConfig = TraceConfig.getDefault();
+    given(tracerSdkProvider.getActiveTraceConfig()).willReturn(traceConfig);
+
     // when
     underTest.configure(tracerSdkProvider);
 
     // then
     then(tracerSdkProvider).should().addSpanProcessor(isA(JdbcSpanRenamingProcessor.class));
+    then(tracerSdkProvider).should().updateActiveTraceConfig(traceConfigCaptor.capture());
     then(tracerSdkProvider).shouldHaveNoMoreInteractions();
+
+    assertEquals(Sampler.alwaysOn(), traceConfigCaptor.getValue().getSampler());
   }
 
   @Test
@@ -52,25 +66,36 @@ public void shouldNotAddSpanProcessorsIfPropertiesAreSetToAnythingElse() {
     SplunkTracerCustomizer underTest = new SplunkTracerCustomizer();
     System.setProperty(ENABLE_JDBC_SPAN_LOW_CARDINALITY_NAME_PROPERTY, "whatever");
 
+    TraceConfig traceConfig = TraceConfig.getDefault();
+    given(tracerSdkProvider.getActiveTraceConfig()).willReturn(traceConfig);
+
     // when
     underTest.configure(tracerSdkProvider);
 
     // then
-    then(tracerSdkProvider).shouldHaveNoInteractions();
+    then(tracerSdkProvider).should().updateActiveTraceConfig(traceConfigCaptor.capture());
+    then(tracerSdkProvider).shouldHaveNoMoreInteractions();
+
+    assertEquals(Sampler.alwaysOn(), traceConfigCaptor.getValue().getSampler());
   }
 
   @Test
   public void shouldConfigureTracerSdkForDefaultValues() {
-
     // given
     SplunkTracerCustomizer underTest = new SplunkTracerCustomizer();
     System.clearProperty(ENABLE_JDBC_SPAN_LOW_CARDINALITY_NAME_PROPERTY);
 
+    TraceConfig traceConfig = TraceConfig.getDefault();
+    given(tracerSdkProvider.getActiveTraceConfig()).willReturn(traceConfig);
+
     // when
     underTest.configure(tracerSdkProvider);
 
     // then
     then(tracerSdkProvider).should().addSpanProcessor(isA(JdbcSpanRenamingProcessor.class));
+    then(tracerSdkProvider).should().updateActiveTraceConfig(traceConfigCaptor.capture());
     then(tracerSdkProvider).shouldHaveNoMoreInteractions();
+
+    assertEquals(Sampler.alwaysOn(), traceConfigCaptor.getValue().getSampler());
   }
 }

smoke-tests/src/test/java/com/splunk/opentelemetry/SpringBootSmokeTest.java

@@ -28,7 +28,9 @@
 class SpringBootSmokeTest extends SmokeTest {
 
   private String getTargetImage(int jdk) {
-    return "open-telemetry-docker-dev.bintray.io/java/smoke-springboot-jdk" + jdk + ":latest";
+    return "open-telemetry-docker-dev.bintray.io/java/smoke-springboot-jdk"
+        + jdk
+        + ":20201105.347264626";
   }
 
   @ParameterizedTest(name = "{index} => SpringBoot SmokeTest On JDK{0}.")