Groovy RESTClient returns inconsistent type on response handler

Question

I am attempting to write my own response handlers for Groovy's RESTClient (which wraps around HttpBuilder). I want to always print the response body if one is returned. However, I cannot find a consistent way to do it.

Typically a custom response handler would look like this:

def client = new RESTClient(url)

client.handler.success = { resp, reader ->
     //do stuff
}

client.handler.failure = { resp, reader ->
     //do stuff
     throw new Exception("HTTP call failed. Status code: ${resp.getStatus()}")
}

However, what I noticed is that the variable "reader" can have a different class depending on the response. I've seen the reader be of type groovy.util.slurpersupport.NodeChild or org.apache.http.conn.EofSensorInputStream. I want it to be a predictable class so I can actually call the methods on this object. What's going on here?

Answer 1

Setting the content type to ANY and changing the HttpBuilder content parsers to the text parser fixed the issue. The type of reader in the response handler is now always java.io.InputStreamReader.

Before:

def headerMap = [:]
//populate headers
def response = client.get("headers":headerMap)

After:

client.parser.'application/xml' = client.parser.'text/plain'
client.parser.'application/xhtml+xml' = client.parser.'text/plain'
client.parser.'application/atom+xml' = client.parser.'text/plain'
client.parser.'application/json' = client.parser.'text/plain'
client.parser.'text/html' = client.parser.'text/plain'
client.parser.'application/x-www-form-urlencoded' = client.parser.'text/plain'
def headerMap = [:]
//populate headers
def response = client.get("headers":headerMap, contentType:groovyx.net.http.ContentType.ANY)