Jmeter Groovy Script to read and utilize header values

Question

I was using jmeter to load test services I need to use one of the response headers parameter value as input of next request. For this I am using JSR223 Sampler and write Grrovy Script to read parameters. I have used

**def headerList = prev.getResponseHeaders()
headerList.each(){
headersList.each{
   log.info it;
   if(it.equals("transactionRef"){
        log.info"Required Header: "it
        requiredHeader=it;
}**

The above code is not working also it is traversing character by character. Could someone help on this.

}

Answer 1

As per the JavaDoc SampleResult.getResponseHeaders() function returns response headers as a single String so if you want to get individual headers you need to split it by line separators first and then by colon to get name/value pairs.

Example code:

def headers = prev.getResponseHeaders().split('\n').inject([:]) { out, header ->
    if (header.contains(':')) {
        header.split(':').with {
            out[it[0].trim()] = it[1].trim()
        }
    }
    out
}

headers.each { header ->
    if (header.getKey() == 'transactionRef') {
        log.info('Required header value: ' + header.getValue())
    }
}

More information on Groovy scripting in JMeter: Apache Groovy - Why and How You Should Use It

---

P.S. Woudln't it be easier to go for Regular Expression Extractor? The relevant configuration would be something like:

Answer 2

Below are steps to add JSR223-based response header assertion:

1. Add a JSR223 Assertion on your sampler
2. Ensure language is groovy as we are going to use groovy
3. Add below script into the JSR223 script:

import java.util.HashMap;

def sanitizeResponseHaders() {
    def headers = new HashMap<String, String>();
    if(SampleResult.getHeadersSize() > 0) {
        def headersData = SampleResult.getResponseHeaders().split("\n");
        for(headerData: headersData) {
            if(headerData.contains(":")) {
                def header = headerData.split(":");
                headers.put(header[0].toLowerCase().trim(), header[1].toLowerCase().trim());        
            }
        }
    }
    return headers;
}

def assertHeader(headers, header, value) {
    if(!headers.get(header).equals(value)) {
        def msg = "Header assertion failed: " + header + " is not as expected " + value + " and actual value is " + headers.get(header);
         SampleResult.setSuccessful(false);
         SampleResult.setResponseMessage(msg);
        AssertionResult.setFailure(true);
        AssertionResult.setFailureMessage(msg);
        addLog(msg);    
    }
}

def addLog(msg) {
   log.info(msg);
}

def logHeaders(headers) {
    for(entry: headers.entrySet()) {
       addLog("header name: " + entry.getKey() + ", value: " + entry.getValue());   
    }
}

addLog("=========== Header assertion started ===============");
def headers = sanitizeResponseHaders();

//Add your own header assertion here
assertHeader(headers, "x-frame-options", "sameorigin");

logHeaders(headers);
addLog("============ Header assertion completed =============");

4. At Add your own header assertion here line, add your own assertion. To do that, just call assertHeader(headers, "your_own_header", "your_own_header_value"); method for each assertion.