Brought back the 128 bit property setting

spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/autoconfig/SleuthProperties.java

@@ -31,6 +31,9 @@ public class SleuthProperties {
 
 	private boolean enabled = true;
 
+	/** When true, generate 128-bit trace IDs instead of 64-bit ones. */
+	private boolean traceId128 = false;
+
 	/**
 	 * List of baggage key names that should be propagated out of process.
 	 * These keys will be prefixed with `baggage` before the actual key.
@@ -59,6 +62,14 @@ public class SleuthProperties {
 		this.enabled = enabled;
 	}
 
+	public boolean isTraceId128() {
+		return this.traceId128;
+	}
+
+	public void setTraceId128(boolean traceId128) {
+		this.traceId128 = traceId128;
+	}
+
 	public List<String> getBaggageKeys() {
 		return this.baggageKeys;
 	}

spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/autoconfig/TraceAutoConfiguration.java

@@ -66,13 +66,15 @@ public class TraceAutoConfiguration {
 			Propagation.Factory factory,
 			CurrentTraceContext currentTraceContext,
 			Reporter<zipkin2.Span> reporter,
-			Sampler sampler) {
+			Sampler sampler, SleuthProperties sleuthProperties) {
 		return Tracing.newBuilder()
 				.sampler(sampler)
 				.localServiceName(serviceName)
 				.propagationFactory(factory)
 				.currentTraceContext(currentTraceContext)
-				.spanReporter(adjustedReporter(reporter)).build();
+				.spanReporter(adjustedReporter(reporter))
+				.traceId128Bit(sleuthProperties.isTraceId128())
+				.build();
 	}
 
 	private Reporter<zipkin2.Span> adjustedReporter(Reporter<zipkin2.Span> delegate) {