我已经使用Spring RestTemplate有一段时间了，当我试图调试它的请求和响应时，我总是碰壁。我基本上希望看到与打开“verbose”选项时使用curl时相同的东西。例如:
curl -v http://twitter.com/statuses/public_timeline.rss
将显示发送的数据和接收的数据(包括头、cookie等)。
我看了一些相关的帖子，比如:
如何在Spring RestTemplate中记录响应?
但我还没能解决这个问题。
实现这一点的一种方法是实际更改RestTemplate源代码，并在那里添加一些额外的日志记录语句，但我认为这种方法确实是最后的办法。应该有某种方法告诉Spring Web Client/RestTemplate以一种更友好的方式记录所有内容。
我的目标是能够用如下代码做到这一点:
restTemplate.put("http://someurl", objectToPut, urlPathValues);
然后在日志文件或控制台中获得相同类型的调试信息(就像我使用curl获得的一样)。
我相信这对于任何使用Spring RestTemplate并且遇到问题的人来说都是非常有用的。使用curl来调试RestTemplate问题是行不通的(在某些情况下)。
正如@MilacH指出的，在实现中有一个错误。如果返回statusCode > 400，则从拦截器抛出IOException，因为没有调用errorHandler。可以忽略异常，然后在处理程序方法中再次捕获异常。
package net.sprd.fulfillment.common;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.http.HttpRequest;
import org.springframework.http.client.ClientHttpRequestExecution;
import org.springframework.http.client.ClientHttpRequestInterceptor;
import org.springframework.http.client.ClientHttpResponse;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import static java.nio.charset.StandardCharsets.UTF_8;
public class LoggingRequestInterceptor implements ClientHttpRequestInterceptor {
final static Logger log = LoggerFactory.getLogger(LoggingRequestInterceptor.class);
@SuppressWarnings("HardcodedLineSeparator")
public static final char LINE_BREAK = '\n';
@Override
public ClientHttpResponse intercept(HttpRequest request, byte[] body, ClientHttpRequestExecution execution) throws IOException {
try {
traceRequest(request, body);
} catch (Exception e) {
log.warn("Exception in LoggingRequestInterceptor while tracing request", e);
}
ClientHttpResponse response = execution.execute(request, body);
try {
traceResponse(response);
} catch (IOException e) {
// ignore the exception here, as it will be handled by the error handler of the restTemplate
log.warn("Exception in LoggingRequestInterceptor", e);
}
return response;
}
private void traceRequest(HttpRequest request, byte[] body) {
log.info("===========================request begin================================================");
log.info("URI : {}", request.getURI());
log.info("Method : {}", request.getMethod());
log.info("Headers : {}", request.getHeaders());
log.info("Request body: {}", new String(body, UTF_8));
log.info("==========================request end================================================");
}
private void traceResponse(ClientHttpResponse response) throws IOException {
StringBuilder inputStringBuilder = new StringBuilder();
try (BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(response.getBody(), UTF_8))) {
String line = bufferedReader.readLine();
while (line != null) {
inputStringBuilder.append(line);
inputStringBuilder.append(LINE_BREAK);
line = bufferedReader.readLine();
}
}
log.info("============================response begin==========================================");
log.info("Status code : {}", response.getStatusCode());
log.info("Status text : {}", response.getStatusText());
log.info("Headers : {}", response.getHeaders());
log.info("Response body: {}", inputStringBuilder);
log.info("=======================response end=================================================");
}
}
正如@MilacH指出的，在实现中有一个错误。如果返回statusCode > 400，则从拦截器抛出IOException，因为没有调用errorHandler。可以忽略异常，然后在处理程序方法中再次捕获异常。
package net.sprd.fulfillment.common;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.http.HttpRequest;
import org.springframework.http.client.ClientHttpRequestExecution;
import org.springframework.http.client.ClientHttpRequestInterceptor;
import org.springframework.http.client.ClientHttpResponse;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import static java.nio.charset.StandardCharsets.UTF_8;
public class LoggingRequestInterceptor implements ClientHttpRequestInterceptor {
final static Logger log = LoggerFactory.getLogger(LoggingRequestInterceptor.class);
@SuppressWarnings("HardcodedLineSeparator")
public static final char LINE_BREAK = '\n';
@Override
public ClientHttpResponse intercept(HttpRequest request, byte[] body, ClientHttpRequestExecution execution) throws IOException {
try {
traceRequest(request, body);
} catch (Exception e) {
log.warn("Exception in LoggingRequestInterceptor while tracing request", e);
}
ClientHttpResponse response = execution.execute(request, body);
try {
traceResponse(response);
} catch (IOException e) {
// ignore the exception here, as it will be handled by the error handler of the restTemplate
log.warn("Exception in LoggingRequestInterceptor", e);
}
return response;
}
private void traceRequest(HttpRequest request, byte[] body) {
log.info("===========================request begin================================================");
log.info("URI : {}", request.getURI());
log.info("Method : {}", request.getMethod());
log.info("Headers : {}", request.getHeaders());
log.info("Request body: {}", new String(body, UTF_8));
log.info("==========================request end================================================");
}
private void traceResponse(ClientHttpResponse response) throws IOException {
StringBuilder inputStringBuilder = new StringBuilder();
try (BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(response.getBody(), UTF_8))) {
String line = bufferedReader.readLine();
while (line != null) {
inputStringBuilder.append(line);
inputStringBuilder.append(LINE_BREAK);
line = bufferedReader.readLine();
}
}
log.info("============================response begin==========================================");
log.info("Status code : {}", response.getStatusCode());
log.info("Status text : {}", response.getStatusText());
log.info("Headers : {}", response.getHeaders());
log.info("Response body: {}", inputStringBuilder);
log.info("=======================response end=================================================");
}
}
在Spring Boot中，您可以通过在属性中设置这个(或其他12因素方法)来获得完整的请求/响应。
logging.level.org.apache.http=DEBUG
这个输出
-DEBUG .i.c.DefaultHttpClientConnectionOperator : Connecting to localhost/127.0.0.1:41827
-DEBUG .i.c.DefaultHttpClientConnectionOperator : Connection established 127.0.0.1:39546<->127.0.0.1:41827
-DEBUG o.a.http.impl.execchain.MainClientExec : Executing request POST /v0/users HTTP/1.1
-DEBUG o.a.http.impl.execchain.MainClientExec : Target auth state: UNCHALLENGED
-DEBUG o.a.http.impl.execchain.MainClientExec : Proxy auth state: UNCHALLENGED
-DEBUG org.apache.http.headers : http-outgoing-0 >> POST /v0/users HTTP/1.1
-DEBUG org.apache.http.headers : http-outgoing-0 >> Content-Type: application/json;charset=UTF-8
-DEBUG org.apache.http.headers : http-outgoing-0 >> Content-Length: 56
-DEBUG org.apache.http.headers : http-outgoing-0 >> Host: localhost:41827
-DEBUG org.apache.http.headers : http-outgoing-0 >> Connection: Keep-Alive
-DEBUG org.apache.http.headers : http-outgoing-0 >> User-Agent: Apache-HttpClient/4.5.2 (Java/1.8.0_102)
-DEBUG org.apache.http.headers : http-outgoing-0 >> Accept-Encoding: gzip,deflate
-DEBUG org.apache.http.wire : http-outgoing-0 >> "POST /v0/users HTTP/1.1[\r][\n]"
-DEBUG org.apache.http.wire : http-outgoing-0 >> "Content-Type: application/json;charset=UTF-8[\r][\n]"
-DEBUG org.apache.http.wire : http-outgoing-0 >> "Content-Length: 56[\r][\n]"
-DEBUG org.apache.http.wire : http-outgoing-0 >> "Host: localhost:41827[\r][\n]"
-DEBUG org.apache.http.wire : http-outgoing-0 >> "Connection: Keep-Alive[\r][\n]"
-DEBUG org.apache.http.wire : http-outgoing-0 >> "User-Agent: Apache-HttpClient/4.5.2 (Java/1.8.0_102)[\r][\n]"
-DEBUG org.apache.http.wire : http-outgoing-0 >> "Accept-Encoding: gzip,deflate[\r][\n]"
-DEBUG org.apache.http.wire : http-outgoing-0 >> "[\r][\n]"
-DEBUG org.apache.http.wire : http-outgoing-0 >> "{"id":null,"email":"xenoterracide@gmail.com","new":true}"
和响应
-DEBUG .i.c.DefaultHttpClientConnectionOperator : Connecting to localhost/127.0.0.1:41827
-DEBUG .i.c.DefaultHttpClientConnectionOperator : Connection established 127.0.0.1:39546<->127.0.0.1:41827
-DEBUG o.a.http.impl.execchain.MainClientExec : Executing request POST /v0/users HTTP/1.1
-DEBUG o.a.http.impl.execchain.MainClientExec : Target auth state: UNCHALLENGED
-DEBUG o.a.http.impl.execchain.MainClientExec : Proxy auth state: UNCHALLENGED
-DEBUG org.apache.http.headers : http-outgoing-0 >> POST /v0/users HTTP/1.1
-DEBUG org.apache.http.headers : http-outgoing-0 >> Content-Type: application/json;charset=UTF-8
-DEBUG org.apache.http.headers : http-outgoing-0 >> Content-Length: 56
-DEBUG org.apache.http.headers : http-outgoing-0 >> Host: localhost:41827
-DEBUG org.apache.http.headers : http-outgoing-0 >> Connection: Keep-Alive
-DEBUG org.apache.http.headers : http-outgoing-0 >> User-Agent: Apache-HttpClient/4.5.2 (Java/1.8.0_102)
-DEBUG org.apache.http.headers : http-outgoing-0 >> Accept-Encoding: gzip,deflate
-DEBUG org.apache.http.wire : http-outgoing-0 >> "POST /v0/users HTTP/1.1[\r][\n]"
-DEBUG org.apache.http.wire : http-outgoing-0 >> "Content-Type: application/json;charset=UTF-8[\r][\n]"
-DEBUG org.apache.http.wire : http-outgoing-0 >> "Content-Length: 56[\r][\n]"
-DEBUG org.apache.http.wire : http-outgoing-0 >> "Host: localhost:41827[\r][\n]"
-DEBUG org.apache.http.wire : http-outgoing-0 >> "Connection: Keep-Alive[\r][\n]"
-DEBUG org.apache.http.wire : http-outgoing-0 >> "User-Agent: Apache-HttpClient/4.5.2 (Java/1.8.0_102)[\r][\n]"
-DEBUG org.apache.http.wire : http-outgoing-0 >> "Accept-Encoding: gzip,deflate[\r][\n]"
-DEBUG org.apache.http.wire : http-outgoing-0 >> "[\r][\n]"
-DEBUG org.apache.http.wire : http-outgoing-0 >> "{"id":null,"email":"xenoterracide@gmail.com","new":true}"
或者只是loginging.level.org.apache.http.wire =DEBUG，它似乎包含了所有相关信息
我的日志记录器配置使用XML
<logger name="org.springframework.web.client.RestTemplate">
<level value="trace"/>
</logger>
然后你会得到如下内容:
DEBUG org.springframework.web.client.HttpMessageConverterExtractor.extractData(HttpMessageConverterExtractor.java:92) : Reading [com.test.java.MyClass] as "application/json" using [org.springframework.http.converter.json.MappingJackson2HttpMessageConverter@604525f1]
通过HttpMessageConverterExtractor.java:92，你需要继续调试，在我的情况下，我得到了这个:
genericMessageConverter.write(requestBody, requestBodyType, requestContentType, httpRequest);
这:
outputMessage.getBody().flush();
outputMessage.getBody()包含http(post类型)发送的消息
