<dependencyManagement>
    <dependencies>
        <dependency>
            <groupId>io.micrometer</groupId>
            <artifactId>micrometer-tracing-bom</artifactId>
            <version>${micrometer-tracing.version}</version>
            <type>pom</type>
            <scope>import</scope>
        </dependency>
    </dependencies>
</dependencyManagement>
<dependencies>
    <dependency>
      <groupId>io.micrometer</groupId>
      <artifactId>micrometer-tracing</artifactId>
    </dependency>
</dependencies>

<dependency>
    <groupId>io.micrometer</groupId>
    <artifactId>micrometer-tracing-bridge-brave</artifactId>
</dependency>
<dependency>
    <groupId>io.zipkin.reporter2</groupId>
    <artifactId>zipkin-reporter-brave</artifactId>
    <version>2.16.3</version>
</dependency>
<dependency>
    <groupId>io.zipkin.reporter2</groupId>
    <artifactId>zipkin-sender-urlconnection</artifactId>
    <version>2.16.3</version>
</dependency>

curl -sSL https://zipkin.io/quickstart.sh | bash -s
java -jar zipkin.jar

import brave.Tracing;
import brave.baggage.BaggageField;
import brave.baggage.BaggagePropagation;
import brave.baggage.BaggagePropagationConfig;
import brave.handler.SpanHandler;
import brave.propagation.B3Propagation;
import brave.propagation.StrictCurrentTraceContext;
import brave.sampler.Sampler;
import io.micrometer.tracing.CurrentTraceContext;
import io.micrometer.tracing.Span;
import io.micrometer.tracing.Tracer;
import io.micrometer.tracing.brave.bridge.BraveBaggageManager;
import io.micrometer.tracing.brave.bridge.BraveCurrentTraceContext;
import io.micrometer.tracing.brave.bridge.BraveTracer;
import zipkin2.reporter.AsyncReporter;
import zipkin2.reporter.brave.ZipkinSpanHandler;
import zipkin2.reporter.urlconnection.URLConnectionSender;
public class MicrometerTracingBrave {
    public static void main(String[] args) {
        //[Brave component]使用SpanHandler的示例。
        // SpanHandler是一个在完成跨度时调用的组件。
        // 这里我们有一个设置示例，通过UrlConnectionSender（通过<io.Zipkin.reporter2:Zipkin-sender-urlconnection>依赖项）
        // 以Zipkin格式将跨度发送到所提供的位置。另一个选项可以是使用TestSpanHandler进行测试
        SpanHandler spanHandler = ZipkinSpanHandler
                .create(AsyncReporter.create(URLConnectionSender.create("http://localhost:9411/api/v2/spans")));
        // 〔Brave组件〕CurrentTraceContext是一个Brave组件，它允许您检索当前TraceContext。
        StrictCurrentTraceContext braveCurrentTraceContext = StrictCurrentTraceContext.create();
        // [Micrometer Tracing 组件] Brave的CurrentTraceContext的Micrometer包装类型
        CurrentTraceContext bridgeContext = new BraveCurrentTraceContext(braveCurrentTraceContext);
        // [Brave组件]跟踪是根组件，允许配置跟踪程序、处理程序、上下文传播等。
        Tracing tracing = Tracing.newBuilder().currentTraceContext(braveCurrentTraceContext).supportsJoin(false)
                .traceId128Bit(true)
                // 要使Baggage（行李）正常工作，您需要提供要传播的字段列表
             .propagationFactory(BaggagePropagation.newFactoryBuilder(B3Propagation.FACTORY)
                        .add(BaggagePropagationConfig.SingleBaggageField
                                .remote(BaggageField.create("from_span_in_scope 1")))
                        .build()).sampler(Sampler.ALWAYS_SAMPLE).addSpanHandler(spanHandler).build();
        // [Brave 组件] Tracer是用于处理跨度生命周期的组件
        brave.Tracer braveTracer = tracing.tracer();
        //--------上面主要是brave创建Tracer追踪器的逻辑，可以随时替换为其他链路追踪系统-------//
        //--------下面是Micrometer Tracing门面做的操作---------------------------------//
        // [Micrometer Tracing 组件] Micrometer Tracing包装类型，包装了Brave‘s Tracer的Tracer
        Tracer tracer = new BraveTracer(braveTracer, bridgeContext, new BraveBaggageManager());
        // 创建跨度。如果此线程中存在span，它将成为“newSpan”的父级。
        Span newSpan = tracer.nextSpan().name("calculateTax");
        // 开始一个跨度并将其放在范围内。放入范围意味着将范围放在本地线程中，如果已配置，则调整MDC以包含跟踪信息
        try (Tracer.SpanInScope ws = tracer.withSpan(newSpan.start())) {
            // 您可以标记一个span-在其上放置一个键值对，以便更好地调试
            newSpan.tag("taxValue", "value");
            // 记录一个事件
            newSpan.event("taxCalculated");
        }
        finally {
            // 一旦完成，记得结束跨度。这将允许收集跨度并将其发送到分布式跟踪系统，例如Zipkin
            newSpan.end();
        }
    }
}

curl -sSL https://zipkin.io/quickstart.sh | bash -s
java -jar zipkin.jar