#!/bin/bash
# refer: https://www.baeldung.com/linux/check-website-availablilty and https://curl.se/mail/archive-2022-04/0027.html
trap "exit 1" TERM
export TOP_PID=$$
STDOUTFILE=".tempCurlStdOut" # temp file to store stdout
> $STDOUTFILE # cleans the file content
# Argument parsing follows our specification
for i in "$@"; do
case $i in
# http*)
# WEBPAGE="${i#*=}"
# shift
# ;;
-n=*|--notWantedContent=*)
NOTWANTEDCONTENT="${i#*=}"
shift
;;
-r=*|--requiredContent=*)
REQUIREDCONTENT="${i#*=}"
shift
;;
-e=*|--email=*)
EMAIL="${i#*=}"
shift
;;
-s|--silent)
SILENT=true
shift
;;
-t|--testTcpPortOnly)
TESTTCPPORTONLY=true
shift
;;
# *)
# >&2 echo "Unknown option: $i" # stderr
# exit 1
# ;;
*)
WEBPAGE="${i#*=}"
shift
;;
*)
;;
esac
done
if test -z "$WEBPAGE"; then
>&2 echo "Missing required URL" # stderr
exit 1;
fi
function tcp_port_is_open {
local exit_status_code
# curl -t '' --connect-timeout 2 -s telnet://"$1:$2" </dev/null
URL=${WEBPAGE#*//*}
curl -t '' --connect-timeout 2 -s telnet://"$URL" </dev/null
exit_status_code=$?
case $exit_status_code in
49) return 0 ;;
*) return "$exit_status_code" ;;
esac
}
function stdOutput {
if ! test "$SILENT" = true; then
echo "$1"
fi
}
function stdError {
if ! test "$SILENT" = true; then
>&2 echo "$1" # stderr
fi
if ! test -z "$EMAIL"; then
echo -e "Subject: $WEBPAGE is not working\n\nThe error is: $1" | msmtp $EMAIL
fi
kill -s TERM $TOP_PID # abort the script execution
}
if tcp_port_is_open > /dev/null 2>&1 ; then
if test "$TESTTCPPORTONLY" = true; then
stdOutput "TCP port is open -> OK"
else
# stdOutput "Internet connectivity OK"
HTTPCODE=$(curl --max-time 5 --silent --write-out %{response_code} --output "$STDOUTFILE" "$WEBPAGE")
CONTENT=$(<$STDOUTFILE) # if there are no errors, this is the HTML code of the web page
if test $HTTPCODE -eq 200; then
stdOutput "HTTP STATUS CODE $HTTPCODE -> OK"
else
stdError "HTTP STATUS CODE $HTTPCODE -> Has something gone wrong?"
fi
if ! test -z "$NOTWANTEDCONTENT"; then
if echo "$CONTENT" | grep -iq "$NOTWANTEDCONTENT"; then # case insensitive check
stdError "Not wanted content '$NOTWANTEDCONTENT'"
fi
fi
if ! test -z "$REQUIREDCONTENT"; then
if ! echo "$CONTENT" | grep -iq "$REQUIREDCONTENT"; then # case insensitive check
stdError "Required content '$REQUIREDCONTENT' is absent"
fi
fi
if echo "$WEBPAGE" | grep -iq "https"; then # case insensitive check
EXPIREDATE=$(curl --max-time 5 --verbose --head --stderr - "$WEBPAGE" | grep "expire date" | cut -d":" -f 2- | date -f - "+%s")
DAYS=$(( ($EXPIREDATE - $(date "+%s")) / (60*60*24) )) # days remaining to expiration
if test $DAYS -gt 7; then
stdOutput "No need to renew the SSL certificate. It will expire in $DAYS days."
else
if test $DAYS -gt 0; then
stdError "The SSL certificate should be renewed as soon as possible ($DAYS remaining days)."
else
stdError "The SSL certificate IS ALREADY EXPIRED!"
fi
fi
fi
fi
else
stdError "TCP port is close -> Has something gone wrong?"
exit 1
fi
例子：
liujia@moni:~/check$ ./c.sh anqun.org:3389 -t
TCP port is close -> Has something gone wrong?
liujia@moni:~/check$ ./c.sh anqun.org:3390 -t
TCP port is open -> OK
liujia@moni:~/check$ ./c.sh http://anqun.org:80
HTTP STATUS CODE 200 -> OK
liujia@moni:~/check$ ./c.sh https://anqun.org:443
TCP port is close -> Has something gone wrong?
liujia@moni:~/check$ ./c.sh https://liujia.anqun.org:443
HTTP STATUS CODE 200 -> OK
No need to renew the SSL certificate. It will expire in 59 days.
liujia@moni:~/check$ ./c.sh https://hy.anqun.org:443 -e=i@liujia.anqun.org
TCP port is close -> Has something gone wrong?