skywalking展示http请求和响应

1.效果图

可以在请求中看到自定义请求信息input和返回值output，方便快速定位问题

2.添加依赖

		<dependency>
			<groupId>org.apache.skywalking</groupId>
			<artifactId>apm-toolkit-trace</artifactId>
			<version>9.1.0</version>
			<scope>provided</scope>
		</dependency>

3.核心语法

//将入参发送skywalking
ActiveSpan.tag("input", sb.toString());
//将返回值发送skywalking
ActiveSpan.tag("output", responseBody);

4.添加过滤器在过滤器中发送到skywalking

因为HttpServletRequest和HttpServletResponse中的body只能读取一次，如果在Filte中读取的话，应用本身就读取不到，所以需要使用ContentCachingRequestWrapper和ContentCachingResponseWrapper，所以需要添加一个过滤器即可

 
import java.io.IOException;
import java.nio.charset.StandardCharsets;
import java.util.Enumeration;
import java.util.Set;
import java.util.stream.Collectors;
 
import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.http.HttpFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
 
import org.apache.skywalking.apm.toolkit.trace.ActiveSpan;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;
import org.springframework.web.util.ContentCachingRequestWrapper;
import org.springframework.web.util.ContentCachingResponseWrapper;
 
import com.google.common.collect.ImmutableSet;
 
@Component
public class ApmHttpInfo extends HttpFilter {
 
	private Logger log = LoggerFactory.getLogger(getClass());
	private static final ImmutableSet IGNORED_HEADERS;
	static {
		Set ignoredHeaders = ImmutableSet.of("Content-Type", "User-Agent", "Accept", "Cache-Control",
				"Postman-Token", "Host", "Accept-Encoding", "Connection", "Content-Length").stream()
				.map(String::toUpperCase).collect(Collectors.toSet());
		IGNORED_HEADERS = ImmutableSet.copyOf(ignoredHeaders);
	}
 
	@Override
	public void doFilter(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain)
			throws IOException, ServletException {
		ContentCachingRequestWrapper requestWrapper = new ContentCachingRequestWrapper(request);
		ContentCachingResponseWrapper responseWrapper = new ContentCachingResponseWrapper(response);
 
		try {
			filterChain.doFilter(requestWrapper, responseWrapper);
		} finally {
			try {
				// 构造请求信息: 比如 curl -X GET http://localhost:18080/getPerson?id=1 -H 'token:
				// me-token' -d '{ "name": "hello" }'
				// 构造请求的方法&URL&参数
				StringBuilder sb = new StringBuilder("curl").append(" -X ").append(request.getMethod()).append(" ")
						.append(request.getRequestURL().toString());
				if (StringUtils.hasLength(request.getQueryString())) {
					sb.append("?").append(request.getQueryString());
				}
 
				// 构造header
				Enumeration headerNames = request.getHeaderNames();
				while (headerNames.hasMoreElements()) {
					String headerName = headerNames.nextElement();
					if (!IGNORED_HEADERS.contains(headerName.toUpperCase())) {
						sb.append(" -H '").append(headerName).append(": ").append(request.getHeader(headerName))
								.append("'");
					}
				}
				// 获取body
				String body = new String(requestWrapper.getContentAsByteArray(), StandardCharsets.UTF_8);
				if (StringUtils.hasLength(body)) {
					sb.append(" -d '").append(body).append("'");
				}
				// 输出到input
				ActiveSpan.tag("input", sb.toString());
 
				// 获取返回值body
				String responseBody = new String(responseWrapper.getContentAsByteArray(), StandardCharsets.UTF_8);
				// 输出到output
				ActiveSpan.tag("output", responseBody);
			} catch (Exception e) {
				log.error("fail to build http log", e);
			} finally {
				// 这一行必须添加，否则就一直不返回
				responseWrapper.copyBodyToResponse();
			}
		}
	}
}