Question

I have been using the Spring RestTemplate for a while and I consistently hit a wall when I’am trying to debug it’s requests and responses. I’m basically looking to see the same things as I see when I use curl with the “verbose” option turned on. For example :

curl -v http://twitter.com/statuses/public_timeline.rss

Would display both the sent data and the received data (including the headers, cookies, etc.).

I have checked some related posts like :
How do I log response in Spring RestTemplate?
but I haven’t managed to solve this issue.

One way to do this would be to actually change the RestTemplate source code and add some extra logging statements there, but I would find this approach really a last resort thing. There should be some way to tell Spring Web Client/RestTemplate to log everything in a much friendlier way.

My goal would be to be able to do this with code like :

restTemplate.put("http://someurl", objectToPut, urlPathValues);

and then to get the same type of debug information (as I get with curl) in the log file or in the console.
I believe this would be extremely useful for anyone that uses the Spring RestTemplate and has problems. Using curl to debug your RestTemplate problems just doesn’t work (in some cases).

Answer 1

I finally found a way to do this in the right way.
Most of the solution comes from
How do I configure Spring and SLF4J so that I can get logging?

It seems there are two things that need to be done :

1. Add the following line in log4j.properties : log4j.logger.httpclient.wire=DEBUG
2. Make sure spring doesn’t ignore your logging config

The second issue happens mostly to spring environments where slf4j is used (as it was my case).
As such, when slf4j is used make sure that the following two things happen :

1. There is no commons-logging library in your classpath : this can be done by adding the exclusion descriptors in your pom :

           <exclusions><exclusion>
               <groupId>commons-logging</groupId>
               <artifactId>commons-logging</artifactId>
           </exclusion>
       </exclusions>
   

2. The log4j.properties file is stored somewhere in the classpath where spring can find/see it. If you have problems with this, a last resort solution would be to put the log4j.properties file in the default package (not a good practice but just to see that things work as you expect)