# nginx 常用全局变量

| 变量       | 说明    |
| :--------   | :-----   | 
|$args       |请求中的参数，如www.123.com/1.php?a=1&b=2的$args就是a=1&b=2 |
|$content_length |HTTP请求信息里的"Content-Length" |
|$conten_type    |  HTTP请求信息里的"Content-Type"   |
|$document_root|nginx虚拟主机配置文件中的root参数对应的值|
|$document_uri|当前请求中不包含指令的URI，如www.123.com/1.php?a=1&b=2的$document_uri就是1.php,不包含后面的参数|
|$host|主机头，也就是域名|
|$http_user_agent|客户端的详细信息，也就是浏览器的标识，用curl -A可以指定|
|$http_cookie|客户端的cookie信息|
|$limit_rate|如果nginx服务器使用limit_rate配置了显示网络速率，则会显示，如果没有设置， 则显示0|
|$remote_addr|客户端的公网ip|
|$remote_port|客户端的port|
|$remote_user|如果nginx有配置认证，该变量代表客户端认证的用户名|
|$request_body_file|做反向代理时发给后端服务器的本地资源的名称|
|$request_method|请求资源的方式，GET/PUT/DELETE等|
|$request_filename|当前请求的资源文件的路径名称，相当于是$document_root/$document_uri的组合|
|$request_uri|请求的链接，包括$document_uri和$args|
|$scheme|请求的协议，如ftp,http,https|
|$server_protocol|客户端请求资源使用的协议的版本，如HTTP/1.0，HTTP/1.1，HTTP/2.0等|
|$server_addr|服务器IP地址|
|$server_name|服务器的主机名|
|$server_port|服务器的端口号|
|$uri|和$document_uri相同|
|$http_referer|客户端请求时的referer，通俗讲就是该请求是通过哪个链接跳过来的，用curl -e可以指定|
### $args
```bash
[root@localhost vhosts]# cat 123.com.conf
    server {
        listen       80;
        server_name  123.com;
        root   /data/wwwroot/123.com;
        index  index.html index.php;
        rewrite_log on;
        return 200 $args;
   }
[root@localhost vhosts]# curl -x127.0.0.1:80 123.com/2.html?a=1
a=1
[root@localhost vhosts]# curl -x127.0.0.1:80 123.com/2.html?a=1\&b-2
a=1&b-2
```
### $content_length
```bash
[root@localhost vhosts]# curl -x127.0.0.1:80 123.com/2.html?a=1\&b-2 -I
HTTP/1.1 200 OK
Server: nginx/1.23.1
Date: Thu, 18 Aug 2022 03:54:00 GMT
Content-Type: text/html
Content-Length: 7
Connection: keep-alive
```
### $document_root
```bash
[root@localhost vhosts]# cat 123.com.conf
    server {
        listen       80;
        server_name  123.com;
        root   /data/wwwroot/123.com;
        index  index.html index.php;
        rewrite_log on;
        return 200 $document_root;
   }
[root@localhost vhosts]# curl -x127.0.0.1:80 123.com/2.html
/data/wwwroot/123.com
```
### $http_user_agent
```bash
[root@localhost vhosts]# cat 123.com.conf
    server {
        listen       80;
        server_name  123.com;
        root   /data/wwwroot/123.com;
        index  index.html index.php;
        rewrite_log on;
        return 200 $http_user_agent;
   }
[root@localhost vhosts]# curl -A "fix" -x127.0.0.1:80 123.com/2.html
fix
```

## 实战
### 域名跳转(域名重定向)
#### 不带任何条件
```bash
server{
    listen 80;
    server_name www.aminglinux.com;
    rewrite /(.*) http://www.aming.com/$1 permanent;
    .......
    
}

# 测试
[root@localhost vhosts]# cat return.com.conf
    server {
        listen       80;
        server_name  return.com;
        root   /data/wwwroot/return.com;
        index  index.html index.php;
        rewrite /(.*) http://123.com/$1 permanent;
}
[root@localhost vhosts]# curl -x127.0.0.1:80 return.com/1.html -I
HTTP/1.1 301 Moved Permanently
Server: nginx/1.23.1
Date: Thu, 18 Aug 2022 04:43:25 GMT
Content-Type: text/html
Content-Length: 169
Connection: keep-alive
Location: http://123.com/1.html
```

#### 带条件
```bash
server{
    listen 80;
    server_name www.aminglinux.com aminglinux.com;
    if ($host != 'www.aminglinux.com')
    {
        rewrite /(.*) http://www.aminglinux.com/$1 permanent;
    }
    .......
    
}

# 测试
[root@localhost vhosts]# cat return.com.conf
    server {
        listen       80;
        server_name  return.com www.return.com;
        root   /data/wwwroot/return.com;
        index  index.html index.php;
        if ($host != return.com)
        {
        rewrite /(.*) http://123.com/$1 permanent;
        }
}
[root@localhost vhosts]# curl -x127.0.0.1:80 return.com -I
HTTP/1.1 403 Forbidden
Server: nginx/1.23.1
Date: Thu, 18 Aug 2022 04:48:31 GMT
Content-Type: text/html
Content-Length: 153
Connection: keep-alive

[root@localhost vhosts]# curl -x127.0.0.1:80 www.return.com -I
HTTP/1.1 301 Moved Permanently
Server: nginx/1.23.1
Date: Thu, 18 Aug 2022 04:48:38 GMT
Content-Type: text/html
Content-Length: 169
Connection: keep-alive
Location: http://123.com/
```

#### http跳转到https
```bash
server{
    listen 80;
    server_name www.aminglinux.com;
    rewrite /(.*) https://www.aminglinux.com/$1 permanent;
    .......
    
}

# 测试
[root@localhost vhosts]# cat return.com.conf
    server {
        listen       80;
        server_name  return.com www.return.com;
        root   /data/wwwroot/return.com;
        index  index.html index.php;
        rewrite /(.*) https://retrun.com/$1 permanent;
}

[root@localhost vhosts]# curl -x127.0.0.1:80 www.return.com -I
HTTP/1.1 301 Moved Permanently
Server: nginx/1.23.1
Date: Thu, 18 Aug 2022 04:51:39 GMT
Content-Type: text/html
Content-Length: 169
Connection: keep-alive
Location: https://retrun.com/
```
#### 域名访问二级目录
```bash
server{
    listen 80;
    server_name bbs.aminglinux.com;
    rewrite /(.*) http://www.aminglinux.com/bbs/$1 last;
    .......
    
}

# 测试
[root@localhost vhosts]# cat return.com.conf
    server {
        listen       80;
        server_name  return.com www.return.com;
        root   /data/wwwroot/return.com;
        index  index.html index.php;
        rewrite /(.*) http://retrun.com/123/$1 permanent;
}

[root@localhost vhosts]# curl -x127.0.0.1:80 www.return.com/1.html -I
HTTP/1.1 301 Moved Permanently
Server: nginx/1.23.1
Date: Thu, 18 Aug 2022 04:59:24 GMT
Content-Type: text/html
Content-Length: 169
Connection: keep-alive
Location: http://retrun.com/123/1.html
```

#### 静态请求分离
```bash
server{
    listen 80;
    server_name www.aminglinux.com;
    location ~* ^.+.(jpg|jpeg|gif|css|png|js)$
    {
        rewrite /(.*) http://img.aminglinux.com/$1 permanent;
    }

    .......
    
}
#或者：
server{
    listen 80;
    server_name www.aminglinux.com;
    if ( $uri ~* 'jpg|jpeg|gif|css|png|js$')
    {
        rewrite /(.*) http://img.aminglinux.com/$1 permanent;
    }

    .......
    
}

# 测试
[root@localhost vhosts]# !cat
cat return.com.conf
    server {
        listen       80;
        server_name  return.com www.return.com;
        root   /data/wwwroot/return.com;
        index  index.html index.php;
        if ($uri ~* 'jpg|css$')
        {
          rewrite /(.*) http://img.123.com/123/$1 permanent;
        }
}
[root@localhost vhosts]# curl -x127.0.0.1:80 www.return.com/1.html -I
HTTP/1.1 200 OK
Server: nginx/1.23.1
Date: Thu, 18 Aug 2022 05:08:56 GMT
Content-Type: text/html
Content-Length: 9
Last-Modified: Tue, 16 Aug 2022 05:33:08 GMT
Connection: keep-alive
ETag: "62fb2c14-9"
Accept-Ranges: bytes

[root@localhost vhosts]# curl -x127.0.0.1:80 www.return.com/1.html.jpg -I
HTTP/1.1 301 Moved Permanently
Server: nginx/1.23.1
Date: Thu, 18 Aug 2022 05:09:05 GMT
Content-Type: text/html
Content-Length: 169
Connection: keep-alive
Location: http://img.123.com/123/1.html.jpg

[root@localhost vhosts]# curl -x127.0.0.1:80 www.return.com/1.html.css -I
HTTP/1.1 301 Moved Permanently
Server: nginx/1.23.1
Date: Thu, 18 Aug 2022 05:09:10 GMT
Content-Type: text/html
Content-Length: 169
Connection: keep-alive
Location: http://img.123.com/123/1.html.css
```

### 防盗链
```bash
server{
    listen 80;
    server_name www.aminglinux.com;
    location ~* ^.+.(jpg|jpeg|gif|css|png|js|rar|zip|flv)$
    {
        valid_referers none blocked server_names *.aminglinux.com aminglinux.com *.aming.com aming.com;
        if ($invalid_referer)
        {
            rewrite /(.*) http://img.aminglinux.com/images/forbidden.png;
        }
    }

    .......
    
}
#说明：*这里是通配，跟正则里面的*不是一个意思，none指的是referer不存在的情况（curl -e 测试），
      blocked指的是referer头部的值被防火墙或者代理服务器删除或者伪装的情况，
      该情况下，referer头部的值不以http://或者https://开头（curl -e 后面跟的referer不以http://或者https://开头）。
#或者：
    location ~* ^.+.(jpg|jpeg|gif|css|png|js|rar|zip|flv)$
    {
        valid_referers none blocked server_names *.aminglinux.com *.aming.com aminglinux.com aming.com;
        if ($invalid_referer)
        {
            return 403;
        }
    }
```

### 伪静态
```bash
location /  {
    rewrite ^([^\.]*)/topic-(.+)\.html$ $1/portal.php?mod=topic&topic=$2 last;
    rewrite ^([^\.]*)/forum-(\w+)-([0-9]+)\.html$ $1/forum.php?mod=forumdisplay&fid=$2&page=$3 last;
    rewrite ^([^\.]*)/thread-([0-9]+)-([0-9]+)-([0-9]+)\.html$ $1/forum.php?mod=viewthread&tid=$2&extra=page%3D$4&page=$3 last;
    rewrite ^([^\.]*)/group-([0-9]+)-([0-9]+)\.html$ $1/forum.php?mod=group&fid=$2&page=$3 last;
    rewrite ^([^\.]*)/space-(username|uid)-(.+)\.html$ $1/home.php?mod=space&$2=$3 last;
    rewrite ^([^\.]*)/(fid|tid)-([0-9]+)\.html$ $1/index.php?action=$2&value=$3 last;
}
```
### rewrite多个条件的并且
```bash
location /{
    set $rule 0;
    if ($document_uri !~ '^/abc')
    {
        set $rule "${rule}1";
    }
    if ($http_user_agent ~* 'ie6|firefox')
    {
       set $rule "${rule}2";
    }
    if ($rule = "012")
    {
        rewrite /(.*) /abc/$1 redirect;
    }
}
```

--------------------------------------------

## location
### 安装第三方模块
echo-nginx-module
```bash
# 使用git安装模块
yum install -y git

# 克隆源码
cd /usr/local/src/
git clone https://github.com/openresty/echo-nginx-module.git
#或者下载源码上传到服务器
unzip echo-nginx-module-master.zip

# 进入nginx安装目录
cd nginx-1.23.1

# 查看nginx安装目录和已安装模块
nginx -V

# 加载第三方模块
./configure --prefix=/usr/local/nginx --with-http_ssl_module --add-module=/usr/local/src/echo-nginx-module

# 编译安装
make && make install

# 重启nginx
systemctl restart nginx

# 验证
server {
        listen 80;
        server_name lwz.com;
        root /data/www;
        index index.html index.php;

        location = "/10.html"
        {
                echo "10";
        }
}

# 请求
curl -x127.0.0.1:80 lwz.com/10.html
10
```

### location语法
nginx location语法规则：`location [=|~|~*|^~] /uri/ { … }`  
nginx的location匹配的变量是`$uri`  

|符号|说明|
|:--:|:--|
|=|表示精确匹配|
|^~	|表示uri以指定字符或字符串开头|
|~	|表示区分大小写的正则匹配|
|~*	|表示不区分大小写的正则匹配|
|/	|通用匹配，任何请求都会匹配到|

**优先级规则**  
= 高于 ^~ 高于 ~* 等于 ~ 高于 /

```bash
   location = "/12.jpg" { ... }
   如：
   www.aminglinux.com/12.jpg 匹配
   www.aminglinux.com/abc/12.jpg 不匹配
   
   location ^~ "/abc/" { ... }
   如：
   www.aminglinux.com/abc/123.html 匹配
   www.aminglinux.com/a/abc/123.jpg 不匹配
   
   location ~ "png" { ... }
   如：
   www.aminglinux.com/aaa/bbb/ccc/123.png 匹配
   www.aminglinux.com/aaa/png/123.html 匹配
   
   location ~* "png" { ... }
   如：
   www.aminglinux.com/aaa/bbb/ccc/123.PNG 匹配
   www.aminglinux.com/aaa/png/123.html 匹配
   
   location /admin/ { ... }
   如：
   www.aminglinux.com/admin/aaa/1.php 匹配
   www.aminglinux.com/123/admin/1.php 不匹配
```
> 小常识：   
> 有些资料上介绍location支持不匹配 !~，
如： `location !~ 'png'{ ... }`
这是错误的，location不支持 !~

> 如果有这样的需求，可以通过if来实现，
如： `if ($uri !~ 'png') { ... }`

> 注意：location优先级小于if