Testing HTTP Redirects

test_http_redirects.sh

# The check_url recursive function
check_url() {
    THIS_URL="${1}"
    HTTP_RESP_CODE=$(curl -ksI "${THIS_URL}" | grep -i 'HTTP/' | cut -d' ' -f 2)
    echo "${THIS_URL} -> ${HTTP_RESP_CODE}"
    
    if [ "${HTTP_RESP_CODE}" == "301" ] ||  [ "${HTTP_RESP_CODE}" == "302" ]
    then
        HTTP_LOC=$(curl -ksI ${1} | grep -i 'Location: ' | cut -d'_' -f 2)
        HTTP_REDIRECT=$(echo "${HTTP_LOC}" | tail -c +11 | tr -d '\r' | tr -d '\n')
        check_url "${HTTP_REDIRECT}"
    fi
}

# Test a single URL
check_url "http://example.com"

# Test a list of URLs
URL_LIST="
http://example.com
http://google.com
http://www.google.com
"

echo "${URL_LIST}" | while read EACH_URL
do
    if [[ "${EACH_URL}" == "" ]]; then continue; fi
    
    echo "-----------------${EACH_URL}-----------------"
    check_url "${EACH_URL}"
    echo "----------------------------------"
done


# Construct a list of URLs to test from the first column of a .csv file
BASE_URL="https://example.com"
FILENAME="example-redirects.csv"
URL_LIST=$(cat ${FILENAME} | perl -pe 's#^(.*),.*$#'${BASE_URL}'$1#g') # Extract first column from .csv file