tests/gold_tests/headers/forwarded-observer.py

'''
Extract the protocol information from the FORWARDED headers and store it in a log file for later verification.
'''
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#  to you under the Apache License, Version 2.0 (the
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#
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import re

log = open('forwarded.log', 'w')

regexByEqualUuid = re.compile(r'^by=_[0-9a-f-]+$')

byCount = 0
byEqualUuid = "__INVALID__"

def observe(headers):

    global byCount
    global byEqualUuid

    seen = False
    for h in headers.items():
        if h[0].lower() == "forwarded":

            content = h[1]

            if content.startswith("by="):

                byCount += 1

                if ((byCount == 4) or (byCount == 5)) and regexByEqualUuid.match(content):  # "by" should give UUID

                    # I don't think there is a way to know what UUID traffic_server generates, so I just do a crude format
                    # check and make sure the same value is used consistently.

                    byEqualUuid = content

            content = content.replace(byEqualUuid, "__BY_EQUAL_UUID__", 1)

            log.write(content + "\n")
            seen = True

    if not seen:
        log.write("FORWARDED MISSING\n")
    log.write("-\n")
    log.flush()


Hooks.register(Hooks.ReadRequestHook, observe)