count 50x error in nginx error log

50x.sh

#!/bin/bash
# By notsobad

f=$1

if [ "$f" = "" ]; then
	echo "Usage: $0 LOG_FILE" 1>&2
	echo "like: $0 /var/log/nginx/www.xxx.com_log-20160313"
	echo "or: $0 /var/log/nginx/www.xxx.com_log-20160313.gz"
	exit 1
fi

echo "$f" | grep -q ".gz$" && {
	cmd="zcat $f"
} || {
	cmd="cat $f"
}


$cmd | awk '{
	i = 0
	if($9 ~ "^50"){
		url = $7
		i = index(url, "?")
		if(i >= 1){
			url = substr(url, 0, i - 1)
		}
		arr[url] += 1
	}
}
END{
	for(i in arr){
		print(i, arr[i])
	}
}' | sort -n -k2 -r

Wow, nice job! Thanks!