How to automate downloading attachment from Rest API GET response in SoapUI - groovy

Question

I am using SoapUI 5.5.0 and I am trying to automate the download of an .xls attachment from a Rest API GET response.
It does not appear in the attachment tab of the response.
I tried adding "Enable MTOM | true" but the request stop working with
it.
I tried some groovy scripts but I didn't get anything out of what I tried.
**RAW RESPONSE**
HTTP/1.1 201
Set-Cookie: Design_Authorization=VeryLongToken; Max-Age=93600; Expires=Tue, 12-Jan-2021 22:33:22 GMT; Path=/Redacted; HttpOnly
Set-Cookie: JSESSIONID=bunchofnumbers; Path=/Redacted; HttpOnly
Content-Disposition: attachment; filename=SoapUI_Export_DD_20210111_153209.xls
X-Content-Type-Options: nosniff
X-XSS-Protection: 1; mode=block
Cache-Control: no-cache, no-store, max-age=0, must-revalidate
Pragma: no-cache
Expires: 0
X-Frame-Options: DENY
Content-Type: application/vnd.ms-excel
Transfer-Encoding: chunked
After this, the response has a bunch of unreadable characters.
If I look at the XML tab I get this:
**XML RESPONSE**
<data contentType="application/vnd.ms-excel" contentLength="647680">0M8R4KGxGuEAAAAAAAAAAAAAAAAAAAAAOwADAP7/CQAGAAAAAAAAAAAAAAAKAAAAAAAAAAAAAAAAEAAA/v///wAAAAD+////AAAAAAEAAACAAAAAAAEAAIABAAAAAgAAgAIAAAADAACAAwAAAAQAAIAEAAD///...it's very long
Adding this here since I could not get a readable format in my thank you comment below.
I had a null error on the response.getProperty('Content-Disposition').split('=')[1] line.
Since I generate and store the name of the export earlier in the testcase, I get the property and then use it.
This is what I ended with:
import org.apache.commons.io.FileUtils
def testStep = testRunner.testCase.testSteps['test step name']
def response = testStep.testRequest.response
assert response.getContentType() == 'application/vnd.ms-excel'
def data = response.getRawResponseBody()
// define filepath/name
exportname = testRunner.testCase.getPropertyValue("exportName")
reportfolder = (System.getProperty("user.home") + File.separatorChar + "Documents" + File.separatorChar);
def filename = reportfolder + exportname +'.xls'
def file = new File(filename)
FileUtils.writeByteArrayToFile(file, data) `

Answer 1

The body of the response is the file. You have to extract it, something like this:
import org.apache.commons.io.FileUtils
def testStep = testRunner.testCase.testSteps['test step name']
def response = testStep.testRequest.response
assert response.getContentType() == 'application/vnd.ms-excel'
def data = response.getRawResponseBody()
// define some filename
def filename = response.getProperty('Content-Disposition').split('=')[1]
def file = new File(filename)
FileUtils.writeByteArrayToFile(file, data)