Response message:Server response should contain 'Connection' header with value 'Upgrade'

[Former user]

Hi, I am facing the issue "Response message: Server response should contain 'Connection' header with value 'Upgrade'" when trying to open the web socket connection.

I have followed your socket.io-chatserversample.jmx, the initial HTTP Request was successful but WebSocket open connection fails - response body and response headers both are empty.

can you please help me to understand and fix this issue.

[Peter Doornbosch]

• did you use “option 1” or “option 2”?
• in the results for “Websocket Open Connection”, select “Request” tab → “Request body” tab. It should display the Connect URL, what is its value?

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[Stalin Gunasekaran N]

I have found the issue in file WebSocketClient.java line number 500

if (! "upgrade".equals(getLowerCase(serverHeaders.get("Connection"))))  // According to RFC 6455 section 4.1, client must match case-insensative
      throw new HttpUpgradeException("Server response should contain 'Connection' header with value 'Upgrade'");*/

in my case the key 'Connection' has value “Upgrade, Upgrade”

as we check for only “upgrade” it throws the exception

which is added from the if block

do {
    line = httpReader.readLine();
    log.debug("<< " + line);
    if (line != null) {
        String[] values = line.split(":", 2);
        if (values.length > 1) {
            String key = values[0];
            String value = values[1].trim();
            if (serverHeaders.containsKey(key)) {
                log.debug("-- if SH" + key + "," + value);
                serverHeaders.put(key, serverHeaders.get(key) + ", " + value);
            } else {
                log.debug("-- else SH" + key + "," + value);
                serverHeaders.put(key, value);
            }
        }
    }
}
while (line != null && line.trim().length() > 0);  

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[Peter Doornbosch]

Well, you’re right that the plugin does not handle multi-value header correctly, but a server sending a connection header with twice the same value sounds as a bug as well; at least it is quite silly.

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[Ewelina Kalemba]

Stalin and how did you fix this error?

[Stalin Gunasekaran N]

@Ewelina Kalemba

Hi, I have changed the below line to check for “contains” instead of “equals”

WebSocketClient.java line number 500

from

if (! "upgrade".equals(getLowerCase(serverHeaders.get("Connection"))))

to

if(!(getLowerCase(serverHeaders.get("Connection"))).contains(“upgrade”))

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[Ewelina Kalemba]

thx:D

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