script081

题目

注：题目来源于 SHELL24 nginx日志分析2-统计某个时间段的IP 。

假设 nginx 的日志我们存储在 nowcoder.txt 里，格式如下：

192.168.1.20 - - [21/Apr/2020:14:27:49 +0800] "GET /1/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0"
192.168.1.21 - - [21/Apr/2020:15:27:49 +0800] "GET /2/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0"
192.168.1.22 - - [21/Apr/2020:21:27:49 +0800] "GET /3/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0"
192.168.1.23 - - [21/Apr/2020:22:27:49 +0800] "GET /1/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0"
192.168.1.24 - - [22/Apr/2020:15:27:49 +0800] "GET /2/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0"
192.168.1.25 - - [22/Apr/2020:15:26:49 +0800] "GET /3/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0"
192.168.1.20 - - [23/Apr/2020:08:27:49 +0800] "GET /1/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0"
192.168.1.21 - - [23/Apr/2020:09:20:49 +0800] "GET /1/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0"
192.168.1.22 - - [23/Apr/2020:10:27:49 +0800] "GET /1/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0"
192.168.1.22 - - [23/Apr/2020:10:27:49 +0800] "GET /1/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0"
192.168.1.20 - - [23/Apr/2020:14:27:49 +0800] "GET /1/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0"
192.168.1.21 - - [23/Apr/2020:15:27:49 +0800] "GET /2/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0"
192.168.1.22 - - [23/Apr/2020:15:27:49 +0800] "GET /3/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0"
192.168.1.25 - - [23/Apr/2020:16:27:49 +0800] "GET /1/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0"
192.168.1.24 - - [23/Apr/2020:20:27:49 +0800] "GET /2/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0"
192.168.1.25 - - [23/Apr/2020:20:27:49 +0800] "GET /3/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0"
192.168.1.20 - - [23/Apr/2020:20:27:49 +0800] "GET /1/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0"
192.168.1.21 - - [23/Apr/2020:20:27:49 +0800] "GET /1/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0"
192.168.1.22 - - [23/Apr/2020:20:27:49 +0800] "GET /1/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0"
192.168.1.22 - - [23/Apr/2020:22:27:49 +0800] "GET /1/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0"
192.168.1.21 - - [23/Apr/2020:23:27:49 +0800] "GET /1/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0"

现在你需要统计2020年04月23日20-23点的去重IP访问量，你的脚本应该输出

5

脚本一

通过正则表达式提取2020年04月23日20-23点的记录行；然后通过 awk 命令提取第一列，即 IP 地址列；再通过 sort 命令排序；uniq 命令去重；最后 wc 命令统计行数，即访问量。

grep "23/Apr/2020:2[0-3]" nowcoder.txt | awk '{print $1}' | sort | uniq | wc -l

脚本二

跟脚本一原理一样，只不过第一步是通过 awk 命令完成的筛选。

awk '/23\/Apr\/2020:2[0-3]/{print $1}' nowcoder.txt | sort | uniq | wc -l

脚本三

#!/bin/bash

# 声明关联数组
declare -A map

# 循环读取文件中的每一行
while read line; do
	# 转换成数组
	a=($line)
	# 如果该行的日期是2020年04月23日20-23点，那么则将IP地址存入到关联数组中，并统计出现次数
	[[ ${a[3]} =~ 23/Apr/2020:2[0-2] ]] && ((map["${a[0]}"]++))
done < nowcoder.txt

# 最后打印关联数组的长度
printf "${#map[*]}"