Check expected & unexpected HTTP headers

expected.txt

HTTP/1.1 200 OK
Content-Encoding: gzip

test.sh

#!/bin/bash
headers="$(curl -sS -IX GET -H "Accept-Encoding: gzip" www.bbc.com)"

# should not find any unmatched patterns
missingExpected="$(grep -oxFf expected.txt <<< $headers | grep -vxFf - expected.txt)"
expected=$?

# should not find any matched patterns
presentUnexpected="$(grep -oxFf unexpected.txt <<< $headers)"
unexpected=$?

[ "$expected" -eq 0 ] && echo -e "*** Missing expected: ***\n$missingExpected"
[ "$unexpected" -eq 0 ] && echo -e "*** Present unexpected: ***\n$presentUnexpected"

exit $((2 - $expected - $unexpected))

unexpected.txt

Server: nginx