SpringCloud alibaba微服务实战二十九 - 网关统一处理请求响应日志
请求响应日志是日常开发调试定位问题的重要手段，在微服务中引入SpringCloud Gateway后我们希望在网关层统一进行日志的收集。
本节内容将实现以下两个功能：
- 首先我们先定义一个日志体
@Data
public class GatewayLog {
/**访问实例*/
private String targetServer;
/**请求路径*/
private String requestPath;
/**请求方法*/
private String requestMethod;
/**协议 */
private String schema;
/**请求体*/
private String requestBody;
/**响应体*/
private String responseData;
/**请求ip*/
private String ip;
/**请求时间*/
private Date requestTime;
/**响应时间*/
private Date responseTime;
/**执行时间*/
private long executeTime;
}- 【关键】在网关定义日志过滤器，获取输入输出参数
/**
* 日志过滤器，用于记录日志
* @author jianzh5
* @date 2020/3/24 17:17
*/
@Slf4j
@Component
public class AccessLogFilter implements GlobalFilter, Ordered {
@Autowired
private AccessLogService accessLogService;
private final List<HttpMessageReader<?>> messageReaders = HandlerStrategies.withDefaults().messageReaders();
@Override
public int getOrder() {
return -100;
}
@Override
@SuppressWarnings("unchecked")
public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
ServerHttpRequest request = exchange.getRequest();
// 请求路径
String requestPath = request.getPath().pathWithinApplication().value();
Route route = getGatewayRoute(exchange);
String ipAddress = WebUtils.getServerHttpRequestIpAddress(request);
GatewayLog gatewayLog = new GatewayLog();
gatewayLog.setSchema(request.getURI().getScheme());
gatewayLog.setRequestMethod(request.getMethodValue());
gatewayLog.setRequestPath(requestPath);
gatewayLog.setTargetServer(route.getId());
gatewayLog.setRequestTime(new Date());
gatewayLog.setIp(ipAddress);
MediaType mediaType = request.getHeaders().getContentType();
if(MediaType.APPLICATION_FORM_URLENCODED.isCompatibleWith(mediaType) || MediaType.APPLICATION_JSON.isCompatibleWith(mediaType)){
return writeBodyLog(exchange, chain, gatewayLog);
}else{
return writeBasicLog(exchange, chain, gatewayLog);
}
}
private Mono<Void> writeBasicLog(ServerWebExchange exchange, GatewayFilterChain chain, GatewayLog accessLog) {
StringBuilder builder = new StringBuilder();
MultiValueMap<String, String> queryParams = exchange.getRequest().getQueryParams();
for (Map.Entry<String, List<String>> entry : queryParams.entrySet()) {
builder.append(entry.getKey()).append("=").append(StringUtils.join(entry.getValue(), ","));
}
accessLog.setRequestBody(builder.toString());
//获取响应体
ServerHttpResponseDecorator decoratedResponse = recordResponseLog(exchange, accessLog);
return chain.filter(exchange.mutate().response(decoratedResponse).build())
.then(Mono.fromRunnable(() -> {
// 打印日志
writeAccessLog(accessLog);
}));
}
/**
* 解决 request body 只能读取一次问题，
* 参考: org.springframework.cloud.gateway.filter.factory.rewrite.ModifyRequestBodyGatewayFilterFactory
* @param exchange
* @param chain
* @param gatewayLog
* @return
*/
@SuppressWarnings("unchecked")
private Mono writeBodyLog(ServerWebExchange exchange, GatewayFilterChain chain, GatewayLog gatewayLog) {
ServerRequest serverRequest = ServerRequest.create(exchange,messageReaders);
Mono<String> modifiedBody = serverRequest.bodyToMono(String.class)
.flatMap(body ->{
gatewayLog.setRequestBody(body);
return Mono.just(body);
});
// 通过 BodyInserter 插入 body(支持修改body), 避免 request body 只能获取一次
BodyInserter bodyInserter = BodyInserters.fromPublisher(modifiedBody, String.class);
HttpHeaders headers = new HttpHeaders();
headers.putAll(exchange.getRequest().getHeaders());
// the new content type will be computed by bodyInserter
// and then set in the request decorator
headers.remove(HttpHeaders.CONTENT_LENGTH);
CachedBodyOutputMessage outputMessage = new CachedBodyOutputMessage(exchange, headers);
return bodyInserter.insert(outputMessage,new BodyInserterContext())
.then(Mono.defer(() -> {
// 重新封装请求
ServerHttpRequest decoratedRequest = requestDecorate(exchange, headers, outputMessage);
// 记录响应日志
ServerHttpResponseDecorator decoratedResponse = recordResponseLog(exchange, gatewayLog);
// 记录普通的
return chain.filter(exchange.mutate().request(decoratedRequest).response(decoratedResponse).build())
.then(Mono.fromRunnable(() -> {
// 打印日志
writeAccessLog(gatewayLog);
}));
}));
}
/**
* 打印日志
* @author javadaily
* @date 2021/3/24 14:53
* @param gatewayLog 网关日志
*/
private void writeAccessLog(GatewayLog gatewayLog) {
log.info(gatewayLog.toString());
}
private Route getGatewayRoute(ServerWebExchange exchange) {
return exchange.getAttribute(ServerWebExchangeUtils.GATEWAY_ROUTE_ATTR);
}
/**
* 请求装饰器，重新计算 headers
* @param exchange
* @param headers
* @param outputMessage
* @return
*/
private ServerHttpRequestDecorator requestDecorate(ServerWebExchange exchange, HttpHeaders headers,
CachedBodyOutputMessage outputMessage) {
return new ServerHttpRequestDecorator(exchange.getRequest()) {
@Override
public HttpHeaders getHeaders() {
long contentLength = headers.getContentLength();
HttpHeaders httpHeaders = new HttpHeaders();
httpHeaders.putAll(super.getHeaders());
if (contentLength > 0) {
httpHeaders.setContentLength(contentLength);
} else {
// TODO: this causes a 'HTTP/1.1 411 Length Required' // on
// httpbin.org
httpHeaders.set(HttpHeaders.TRANSFER_ENCODING, "chunked");
}
return httpHeaders;
}
@Override
public Flux<DataBuffer> getBody() {
return outputMessage.getBody();
}
};
}
/**
* 记录响应日志
* 通过 DataBufferFactory 解决响应体分段传输问题。
*/
private ServerHttpResponseDecorator recordResponseLog(ServerWebExchange exchange, GatewayLog gatewayLog) {
ServerHttpResponse response = exchange.getResponse();
DataBufferFactory bufferFactory = response.bufferFactory();
return new ServerHttpResponseDecorator(response) {
@Override
public Mono<Void> writeWith(Publisher<? extends DataBuffer> body) {
if (body instanceof Flux) {
Date responseTime = new Date();
gatewayLog.setResponseTime(responseTime);
// 计算执行时间
long executeTime = (responseTime.getTime() - gatewayLog.getRequestTime().getTime());
gatewayLog.setExecuteTime(executeTime);
// 获取响应类型，如果是 json 就打印
String originalResponseContentType = exchange.getAttribute(ServerWebExchangeUtils.ORIGINAL_RESPONSE_CONTENT_TYPE_ATTR);
if (ObjectUtil.equal(this.getStatusCode(), HttpStatus.OK)
&& StringUtil.isNotBlank(originalResponseContentType)
&& originalResponseContentType.contains("application/json")) {
Flux<? extends DataBuffer> fluxBody = Flux.from(body);
return super.writeWith(fluxBody.buffer().map(dataBuffers -> {
// 合并多个流集合，解决返回体分段传输
DataBufferFactory dataBufferFactory = new DefaultDataBufferFactory();
DataBuffer join = dataBufferFactory.join(dataBuffers);
byte[] content = new byte[join.readableByteCount()];
join.read(content);
// 释放掉内存
DataBufferUtils.release(join);
String responseResult = new String(content, StandardCharsets.UTF_8);
gatewayLog.setResponseData(responseResult);
return bufferFactory.wrap(content);
}));
}
}
// if body is not a flux. never got there.
return super.writeWith(body);
}
};
}
}代码较长建议直接拷贝到编辑器，只要注意下面一个关键点：
getOrder()方法返回的值必须要<-1，否则标准的NettyWriteResponseFilter将在您的过滤器被调用的机会之前发送响应，即不会执行获取后端响应参数的方法
通过上面的两步我们已经可以获取到请求的输入输出参数了，在 writeAccessLog()中将其输出到了日志文件，大家可以在Postman发送请求观察日志。
存储日志
如果需要将日志持久化方便后期检索的话可以考虑将日志存储在MongoDB中，实现过程很简单。（安装MongoDB可以参考这篇文章：实战|MongoDB的安装配置）
- 引入MongoDB
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-mongodb-reactive</artifactId>
</dependency>由于gateway是基于webflux，所以我们需要选择reactive版本。
- 在GatewayLog上添加对应的注解
@Data
@Document
public class GatewayLog {
@Id
private String id;
...
}- 建立AccessLogRepository
@Repository
public interface AccessLogRepository extends ReactiveMongoRepository<GatewayLog,String> {
}- 建立Service
public interface AccessLogService {
/**
* 保存AccessLog
* @param gatewayLog 请求响应日志
* @return 响应日志
*/
Mono<GatewayLog> saveAccessLog(GatewayLog gatewayLog);
}- 建立实现类
@Service
public class AccessLogServiceImpl implements AccessLogService {
@Autowired
private AccessLogRepository accessLogRepository;
@Override
public Mono<GatewayLog> saveAccessLog(GatewayLog gatewayLog) {
return accessLogRepository.insert(gatewayLog);
}
}- 在Nacos配置中心添加MongoDB对应配置
spring:
data:
mongodb:
host: xxx.xx.x.xx
port: 27017
database: accesslog
username: accesslog
password: xxxxxx- 执行请求，打开MongoDB客户端，查看日志结果
要不要看点其他的？