$ java -jar /path/to/plantuml.jar

# mac
$ brew install graphviz

# 通用安装方式
./autogen.sh
./configure --prefix=/usr --libdir=/usr/lib64
make -j
make install

# 单机
rate(request_count{label='value',...}[1m])
irate(request_count{label='value',...}[1m])  
# irate 比 rate 更能凸显瞬时值, 或者说 rate 比 irate 更平滑

# 所有机器
sum(rate(request_count{label='value',...}[1m]))

label_replace(query, "dest_label", "replacement", "src_label", "regex")

# 说明
query: 			 查询语句
dest_label:  替换后的 label 名称
replacement: 替换后的 label value 表达式, 支持正则查询后的分组
src_label:   需要替换的 label
regex:       需要替换的 label value 正则表达式

label_replace(up{job="node-exporter"}, "foo", "bar-$1", "job", "node-(.+)")
# 效果
up{foo="bar-exporter"}
# 说明
$1 = exporter

# 使用 time range
rate(label_replace(up{job="node-exporter"}, "foo", "bar-$1", "job", "node-(.+)")[1m:])

sum(rate(label_replace(no_fail_request{job=~"${cluster}"}, "private_ip_address", "$1", "instance", "(.*):8000$")[1m:]) * on (private_ip_address) group_left(zone) agent_status{instance_state="running",region="${cluster}"}) by (zone) / 
sum(rate(label_replace(total_request{job=~"${cluster}"}, "private_ip_address", "$1", "instance", "(.*):8000$")[1m:]) * on (private_ip_address) group_left(zone) agent_status{instance_state="running",region="${cluster}"}) by (zone)

avg(metric_name{] != 0) by (region)  # 对值为 0 的指标不进行 avg 计算
avg(metric_name{]) by (region) ！= 0  # 对值为 0 的结果不进行展示

# receiver
$ nc -l -p {port} > something.tar.gz < /dev/null
# sender
$ cat something.tar.gz | nc {server-ip} {port}

# example
nc -l -p 12345 > something.tar.gz < /dev/null
cat something.zip | nc 127.0.0.1 12345

$ cat msg
{
'localhost' => ['domain_name' => 'default', 'domain_type' => 'mobile'],
}

# 替换文件内容并打印
$ sed '/localhost/p; s/localhost/dev.ops/' msg
{
'localhost' => ['domain_name' => 'default', 'domain_type' => 'mobile'],
'dev.ops' => ['domain_name' => 'default', 'domain_type' => 'mobile'],
}

# 替换文件内容并将输出重定向到新文件
$ sed '/localhost/p; s/localhost/dev.ops/' msg > new_msg
$ cat new_msg
{
'localhost' => ['domain_name' => 'default', 'domain_type' => 'mobile'],
'dev.ops' => ['domain_name' => 'default', 'domain_type' => 'mobile'],
}
# 源文件并未更改
$ cat msg
{
'localhost' => ['domain_name' => 'default', 'domain_type' => 'mobile'],
}

# 在源文件修改并保存源文件至备份文件
$ sed -i 'msg_backup' '/localhost/p; s/localhost/dev.ops/' msg
$ ls
msg		msgmsg_backup	new_msg
# 打印源文件备份
$ cat msgmsg_backup
{
'localhost' => ['domain_name' => 'default', 'domain_type' => 'mobile'],
}
# 打印源文件
$ cat msg
{
'localhost' => ['domain_name' => 'default', 'domain_type' => 'mobile'],
'dev.ops' => ['domain_name' => 'default', 'domain_type' => 'mobile'],
}

# 直接修改源文件并且不保存备份
$ sed -i '/localhost/p; s/localhost/dev.worker/' msgmsg_backup
# $ sed -i '' '/localhost/p; s/localhost/dev.worker/' msgmsg_backup	# os x
$ cat msgmsg_backup
{
'localhost' => ['domain_name' => 'default', 'domain_type' => 'mobile'],
'dev.worker' => ['domain_name' => 'default', 'domain_type' => 'mobile'],
}

$ ls
msg		msgmsg_backup	new_msg

#### Other Examples
## 正则替换
$ cat script/config.sh
workers=6666
threads_compute=10
threads=101
$ sed -i "s/workers=[0-9]*/workers=9/" ./script/config.sh
$ cat script/config.sh
workers=9
threads_compute=10
threads=101

# group
sed -i "s/workers=([0-9]+)/\1/" /path/to/file

sed -i 's/head/heap/g' Heap.cpp
# sed -i '' 's/head/heap/g' Heap.cpp	# 不保留文件备份

sed '/localhost/p; s/localhost/dev.ops/' FILENAME

$ echo "hello wii." | sed -E 's/hello ([a-z]+).*/\1/'
wii
# OR
$ echo "hello wii." | sed 's/hello \([a-z]\+\).*/\1/'   # 注: 不同系统，+ 号的行为可能不一致，这条命令在 big sur (mac os) 中无法输出预想结果
wii

$ echo "hello wii." | sed -E 's/hi ([a-z]+).*/\1/'
hello wii.

$ echo "hello wii." | sed -E '/hi ([a-z]+).*/!d;s//\1/' 
# empty