Dubbo + Zipkin + Brave實現全鏈路追蹤
最近寫了一個鏈路追蹤Demo分享下，實現了鏈路追蹤過程中數據的記錄，還有能擴展的地方，後期再繼續補充。
原理參考上面文章 《Dubbo鏈路追蹤——生成全局ID（traceId）》
實現鏈路追蹤的目的
- 服務調用的流程信息，定位服務調用鏈
- 記錄調用入參及返回值信息，方便問題重現
- 記錄調用時間線，代碼重構及調優處理
- 調用信息統計
分佈式跟蹤系統還有其他比較成熟的實現，例如：Naver的Pinpoint、Apache的HTrace、阿里的鷹眼Tracing、京東的Hydra、新浪的Watchman，美團點評的CAT，skywalking等。 本次主要利用Dubbo數據傳播特性擴展Filter接口來實現鏈路追蹤的目的
重點主要是zipkin及brave使用及特性,當前brave版本爲 5.2.0 爲 2018年8月份發佈的release版本 , zipkin版本爲2.2.1 所需JDK爲1.8
快速啓動zipkin
下載最新的zipkin並啓動
wget -O zipkin.jar 'https://search.maven.org/remote_content?g=io.zipkin.java&a=zipkin-server&v=LATEST&c=exec'
java -jar zipkin.jar
輸入 http://localhost:9411/zipkin/
進入WebUI界面如下
核心源碼
代碼的初步版本：方便描述
import brave.Span;
import brave.Tracer;
import brave.Tracing;
import brave.propagation.*;
import brave.sampler.Sampler;
import com.alibaba.dubbo.common.Constants;
import com.alibaba.dubbo.common.extension.Activate;
import com.alibaba.dubbo.common.json.JSON;
import com.alibaba.dubbo.common.logger.Logger;
import com.alibaba.dubbo.common.logger.LoggerFactory;
import com.alibaba.dubbo.remoting.exchange.ResponseCallback;
import com.alibaba.dubbo.rpc.*;
import com.alibaba.dubbo.rpc.protocol.dubbo.FutureAdapter;
import com.alibaba.dubbo.rpc.support.RpcUtils;
import zipkin2.codec.SpanBytesEncoder;
import zipkin2.reporter.AsyncReporter;
import zipkin2.reporter.Sender;
import zipkin2.reporter.okhttp3.OkHttpSender;
import java.io.IOException;
import java.net.InetSocketAddress;
import java.util.Map;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;
/**
* Created with IntelliJ IDEA.
*
* @author: bakerZhu
* @description:
* @modifytime:
*/
@Activate(group = {Constants.PROVIDER, Constants.CONSUMER})
public class TracingFilter implements Filter {
private static final Logger log = LoggerFactory.getLogger(TracingFilter.class);
private static Tracing tracing;
private static Tracer tracer;
private static TraceContext.Extractor<Map<String, String>> extractor;
private static TraceContext.Injector<Map<String, String>> injector;
static final Propagation.Getter<Map<String, String>, String> GETTER =
new Propagation.Getter<Map<String, String>, String>() {
@Override
public String get(Map<String, String> carrier, String key) {
return carrier.get(key);
}
@Override
public String toString() {
return "Map::get";
}
};
static final Propagation.Setter<Map<String, String>, String> SETTER =
new Propagation.Setter<Map<String, String>, String>() {
@Override
public void put(Map<String, String> carrier, String key, String value) {
carrier.put(key, value);
}
@Override
public String toString() {
return "Map::set";
}
};
static {
// 1
Sender sender = OkHttpSender.create("http://localhost:9411/api/v2/spans");
// 2
AsyncReporter asyncReporter = AsyncReporter.builder(sender)
.closeTimeout(500, TimeUnit.MILLISECONDS)
.build(SpanBytesEncoder.JSON_V2);
// 3
tracing = Tracing.newBuilder()
.localServiceName("tracer-client")
.spanReporter(asyncReporter)
.sampler(Sampler.ALWAYS_SAMPLE)
.propagationFactory(ExtraFieldPropagation.newFactory(B3Propagation.FACTORY, "user-name"))
.build();
tracer = tracing.tracer();
// 4
// 4.1
extractor = tracing.propagation().extractor(GETTER);
// 4.2
injector = tracing.propagation().injector(SETTER);
}
public TracingFilter() {
}
@Override
public Result invoke(Invoker<?> invoker, Invocation invocation) throws RpcException {
RpcContext rpcContext = RpcContext.getContext();
// 5
Span.Kind kind = rpcContext.isProviderSide() ? Span.Kind.SERVER : Span.Kind.CLIENT;
final Span span;
if (kind.equals(Span.Kind.CLIENT)) {
//6
span = tracer.nextSpan();
//7
injector.inject(span.context(), invocation.getAttachments());
} else {
//8
TraceContextOrSamplingFlags extracted = extractor.extract(invocation.getAttachments());
//9
span = extracted.context() != null ? tracer.joinSpan(extracted.context()) : tracer.nextSpan(extracted);
}
if (!span.isNoop()) {
span.kind(kind).start();
//10
String service = invoker.getInterface().getSimpleName();
String method = RpcUtils.getMethodName(invocation);
span.kind(kind);
span.name(service + "/" + method);
InetSocketAddress remoteAddress = rpcContext.getRemoteAddress();
span.remoteIpAndPort(
remoteAddress.getAddress() != null ? remoteAddress.getAddress().getHostAddress() : remoteAddress.getHostName(),remoteAddress.getPort());
}
boolean isOneway = false, deferFinish = false;
try (Tracer.SpanInScope scope = tracer.withSpanInScope(span)){
//11
collectArguments(invocation, span, kind);
Result result = invoker.invoke(invocation);
if (result.hasException()) {
onError(result.getException(), span);
}
// 12
isOneway = RpcUtils.isOneway(invoker.getUrl(), invocation);
// 13
Future<Object> future = rpcContext.getFuture();
if (future instanceof FutureAdapter) {
deferFinish = true;
((FutureAdapter) future).getFuture().setCallback(new FinishSpanCallback(span));// 14
}
return result;
} catch (Error | RuntimeException e) {
onError(e, span);
throw e;
} finally {
if (isOneway) { // 15
span.flush();
} else if (!deferFinish) { // 16
span.finish();
}
}
}
static void onError(Throwable error, Span span) {
span.error(error);
if (error instanceof RpcException) {
span.tag("dubbo.error_msg", RpcExceptionEnum.getMsgByCode(((RpcException) error).getCode()));
}
}
static void collectArguments(Invocation invocation, Span span, Span.Kind kind) {
if (kind == Span.Kind.CLIENT) {
StringBuilder fqcn = new StringBuilder();
Object[] args = invocation.getArguments();
if (args != null && args.length > 0) {
try {
fqcn.append(JSON.json(args));
} catch (IOException e) {
log.warn(e.getMessage(), e);
}
}
span.tag("args", fqcn.toString());
}
}
static final class FinishSpanCallback implements ResponseCallback {
final Span span;
FinishSpanCallback(Span span) {
this.span = span;
}
@Override
public void done(Object response) {
span.finish();
}
@Override
public void caught(Throwable exception) {
onError(exception, span);
span.finish();
}
}
// 17
private enum RpcExceptionEnum {
UNKNOWN_EXCEPTION(0, "unknown exception"),
NETWORK_EXCEPTION(1, "network exception"),
TIMEOUT_EXCEPTION(2, "timeout exception"),
BIZ_EXCEPTION(3, "biz exception"),
FORBIDDEN_EXCEPTION(4, "forbidden exception"),
SERIALIZATION_EXCEPTION(5, "serialization exception"),;
private int code;
private String msg;
RpcExceptionEnum(int code, String msg) {
this.code = code;
this.msg = msg;
}
public static String getMsgByCode(int code) {
for (RpcExceptionEnum error : RpcExceptionEnum.values()) {
if (code == error.code) {
return error.msg;
}
}
return null;
}
}
}
- 構建客戶端發送工具
- 構建異步reporter
- 構建tracing上下文
- 初始化injector 和 Extractor [tab]4.1 extractor 指數據提取對象,用於在carrier中提取TraceContext相關信息或者採樣標記信息到TraceContextOrSamplingFlags 中 -4.2 injector 用於將TraceContext中的各種數據注入到carrier中,其中carrier一半是指數據傳輸中的載體,類似於Dubbo中Invocation中的attachment(附件集合)
- 判斷此次調用是作爲服務端還是客戶端
- rpc客戶端調用會從ThreadLocal中獲取parent的 TraceContext ,爲新生成的Span指定traceId及 parentId如果沒有parent traceContext 則生成的Span爲 root span
- 將Span綁定的TraceContext中 屬性信息 Copy 到 Invocation中達到遠程參數傳遞的作用
- rpc服務提供端 , 從invocation中提取TraceContext相關信息及採樣數據信息
- 生成span , 兼容初次服務端調用
- 記錄接口信息及遠程IP Port
- 將創建的Span 作爲當前Span (可以通過Tracer.currentSpan 訪問到它) 並設置查詢範圍
- oneway調用即只請求不接受結果
- 如果future不爲空則爲 async 調用 在回調中finish span
- 設置異步回調，回調代碼執行span finish() .
- oneway調用 因爲不需等待返回值 即沒有 cr (Client Receive) 需手動flush()
- 同步調用 業務代碼執行完畢後需手動finish()
- 設置枚舉類 與 Dubbo中RpcException保持對應
測試項
- Dubbo sync async oneway 測試
- RPC異常測試
- 普通業務異常測試
- 併發測試
配置方式
POM依賴添加
<dependency>
<groupId>com.github.baker</groupId>
<artifactId>Tracing</artifactId>
<version>1.0-SNAPSHOT</version>
</dependency>
資源目錄根路徑下添加tracing.properties文件
一次調用信息
調用鏈
調用成功失敗彙總
zipkinHost 指定zipkin服務器IP:PORT 默認爲localhost:9411
serviceName 指定應用名稱 默認爲trace-default
調用鏈：
待擴展項
- 抽象數據傳輸（擴展Kafka數據傳輸）
- 調用返回值數據打印
- 更靈活的配置方式