How do I do a website health check using CURL command

Question

I'm trying to monitor a website using curl but the output doesn't seem to work, please see commands below:

#!/bin/bash

varDate=$(date '+%Y-%m-%d %H:%M:%S')
varCurlError=$(curl -sSf https://website.com > /dev/null)
varHttpCode=$(curl -Is https://website.com | head -n 1)
varResponseTime=$(curl -s -w '%{time_total}' -o /dev/null website.com)
varOutput="$varDate | $varCurlError | $varHttpCode | $varResponseTime"
echo $varOutput

The output looks like this:

 | 0.07323 18:51:40 | | HTTP/1.1 200 OK

What can I change or add to fix the output.

Much appreciated.

Answer 1

#!/bin/bash
varDate=$(date '+%Y-%m-%d %H:%M:%S')
varCurlError=$(curl -sSf https://website.com  2>&1 >/dev/null)
varHttpCode=$(curl -Is https://website.com | head -n 1)
varResponseTime=$(curl -s -w '%{time_total}' -o /dev/null website.com | tr -d \\r )
varOutput="$varDate | $varCurlError | $varHttpCode | $varResponseTime"
echo $varOutput

There are two corrections:

1. tr -d \r was added as per glenn jackman. The CR is causing your varResponseTime to be printed at the beginning of the line. The tr command deletes the CR.
2. You need to first redirect stderr to stdout before you close file descriptor 1 in your varCurlError statement. Now, errors reported by curl to stderr will be sent to stdout (and captured by your $() enclosure). The output curl sends to stdout will go to the bitbucket. Order is important . >/dev/null 2>&1 doesn't work - it sends stdout and stderr to /dev/null.

Answer 2

@glenn jackman is correct about the need to pipe the curl output to | tr -d '\r' | tr -d '\r' That is, change your code to

#!/bin/bash
varDate=$(date '+%Y-%m-%d %H:%M:%S' | tr -d '\r')
varCurlError=$(curl -sSf https://website.com | tr -d '\r' > /dev/null)
varHttpCode=$(curl -Is https://website.com | tr -d '\r' | head -n 1)
varResponseTime=$(curl -s -w '%{time_total}' -o /dev/null website.com | tr -d '\r')
varOutput="$varDate | $varCurlError | $varHttpCode | $varResponseTime"
echo "$varOutput"

Answer 3

It can be done with wget so you see if you can get any data and it can be simple like this:

#!/bin/bash
dt=$(date '+%d/%m/%Y %H:%M:%S');
wget domain/yourindex
if [ -f /home/$USER/yourindex ] ; then
#echo $dt GOOD  >> /var/log/fix.log
echo GOOD >/dev/null 2>&1
else
#counter measures like sudo systemctl restart php7.2-fpm.service && sudo systemctl restart nginx
echo $dt BROKEN >> /var/log/fix.log
fi
rm login*
exit