This script adds additional header on request header only if spcific host request is issued

burp_additonal_request_header_extension.py

from burp import IBurpExtender
from burp import IHttpListener

class BurpExtender(IBurpExtender, IHttpListener):
    def registerExtenderCallbacks(self, callbacks):
        self._callbacks = callbacks
        self._helpers = callbacks.getHelpers()
        callbacks.setExtensionName("Homemade Extension")
        callbacks.registerHttpListener(self)
        return

    def processHttpMessage(self, toolFlag, messageIsRequest, currentRequest):
        if not messageIsRequest:
            return

        # header
        requestInfo = self._helpers.analyzeRequest(currentRequest)
        headers = requestInfo.getHeaders()
        headersArray = list(headers)

        # body
        bodyBytes = currentRequest.getRequest()[requestInfo.getBodyOffset():]
        bodyStr = self._helpers.bytesToString(bodyBytes)

        # add X-TORIPIYO header to request header only if request is to "toripiyo.hatenablog.com" host
        url = requestInfo.getUrl()
        host = url.getHost()
        # print host # for debug
        
        if host == ('toripiyo.hatenablog.com'):

            # set new headers
            newHeader = "X-TORIPIYO: piyopiyo"
            headersArray.append(newHeader)

        # set new request
        newRequest = self._helpers.buildHttpMessage(headersArray, bodyStr)
        currentRequest.setRequest(newRequest)

        return