POST error when sending JSON data in Grinder

Question

The requirement is to make a POST request to a particular URL with a given JSON payload. The URL will only respond if the payload is correct and the request is via POST.

This is my code:

request1 = HTTPRequest()
control = HTTPPluginControl.getConnectionDefaults()
httpUtilities = HTTPPluginControl.getHTTPUtilities()
control.setProxyServer("proxy.example.com", 1234)

payload = JSONObject({
  "uaaURL": "https://com-example.something.com",
  "sampleID": "admin",
  "sampleSecret": "password",
  "sampleID2": "example-sample-el",
  "sampleSecret2": "ssenjsoemal/+11=",
  "username": "test",
  "someAttributes": {
    "Groups": [
      "example_com-abc"
    ],
    "attribute": [
      "value1"
    ]
  }
})
payload = str(payload)

url = "https://example-something.com:6443/getvalues"
headers = [
    NVPair('Content-Type', 'application/json'),
    NVPair('Charset', 'UTF-8'),]

class TestRunner:
    def __call__(self):
        result = request1.POST(url, payload, headers)
        print payload, headers

Now the issue with this is that my POST request gives me a 403 forbidden. However, when I use the same payload and send the request using DHC, it gives me a 200. So I'm sure of the payload and the link I'm connecting to. The proxy also I've tested in another script and works fine. Besides, if the proxy didn't work, I wouldn't get a 403 either. Lastly, I'm parsing it as a string because POST requires the second argument to be string that it will internally convert into byte[].

I'm really not able to understand what's happening so any insight would be immensely helpful. Thanks in advance

EDIT: Fiddler's catch of DHC's Request

POST https://example-something.com:6443/getvalues HTTP/1.1
Host: example-something.com:6444
Connection: keep-alive
Content-Length: 688
Origin: chrome-extension://aejoelaoggembcahagimdiliamlcdmfm
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/53.0.2785.116 Safari/537.36
Content-Type: application/json
Accept: */*
Accept-Encoding: gzip, deflate, br
Accept-Language: en-US,en;q=0.8

{
                "uaaURL": "https://com-example.something.com",
                "sampleID": "admin",
                "sampleSecret": "password",
                "sampleID2": "example-sample-el",
                "sampleSecret2": "ssenjsoemal/+11=",
                "username": "test",
                "someAttributes": {
                                "Groups": [
                                  "example_com-abc"
                                ],
                                "attribute": [
                                  "value1"
                                ]
                }
}

I even edited my Grinder request headers to so

headers = (
    NVPair('Content-Type', 'application/json'),
    NVPair('Charset','UTF-8'),
    NVPair('Accept', '*/*'),
    NVPair('Accept-Encoding', 'gzip, deflate, br'),
    NVPair('Accept-Language', 'en-US,en;q=0.8'),
    NVPair('Connection', 'keep-alive'),
    )

Answer 1

The issue was that Grinder was not able to access the port. It had nothing to do with the JSON. The URL, which runs on port 6443 was the problem and Grinder couldn't access that (don't know why). I changed my URL itself to run on the default port 8080 and instantly my script worked. Thanks for the help!

Answer 2

Best guess? You are likely missing a header with some credential information to pass a proxy/firewall/access gate to the application. Your REST Client, DHC, likely is passing this additional data but grinder is not. Grab a proxy (Fiddler, Charles, etc...) and check out the handshake from DHC to your destination and then match that with Grinder. My guess is you will find the delta.