curl命令通过代理访问资源

生产环境中IDC托管的服务器或者云主机通常不具备访问外网权限，部署开源软件一般都是在赋予外网权限的开发机（网关机）下载后再分发到相应集群，操作起来非常不方便。如果开发机启用了http或者socket代理服务，那么我们可以很方便地使用curl命令通过代理服务器访问外网资源下载所需软件或者补丁包。

系统管理员提供的代理详细信息如下：

IP: 202.54.1.1
Port: 3128
Username: foo
Password: bar

IP: 202.54.1.1

Port: 3128

Username: foo

Password: bar

该代理设置在Google Chrome 和 Firefox 浏览器工作的很好。但是，我要如何将其应用到curl命令上呢？我要如何让curl命令使用我在谷歌浏览器上的代理设置呢？

诸如curl 、wget 、lynx 命令等许多 Linux 和 Unix 命令行工具都会使用名为 http_proxy、https_proxy、ftp_proxy 的环境变量来查找代理详细信息。它允许用户通过代理服务器（使用或者不使用用户名/密码）连接基于文本的会话和应用。本文将演示代理服务器环境下如何通过curl命令行界面执行 HTTP/HTTPS 请求。

Unix和Linux下curl命令设置代理语法

语法如下：

## Set the proxy address of your uni/company/vpn network ## 
export http_proxy=http://your-ip-address:port/
 
## http_proxy with username and password 
export http_proxy=http://user:password@your-proxy-ip-address:port/
 
## HTTPS version ##
export https_proxy=https://your-ip-address:port/
export https_proxy=https://user:password@your-proxy-ip-address:port/

## Set the proxy address of your uni/company/vpn network ##

export http_proxy=http://your-ip-address:port/

## http_proxy with username and password

export http_proxy=http://user:password@your-proxy-ip-address:port/

## HTTPS version ##

export https_proxy=https://your-ip-address:port/

export https_proxy=https://user:password@your-proxy-ip-address:port/

另一个方式是使用curl命令的-x选项，该选项允许用户使用指定的代理设置：

curl -x <[protocol://][user:password@]proxyhost[:port]> url
--proxy <[protocol://][user:password@]proxyhost[:port]> url
--proxy http://user:password@Your-Ip-Here:Port url
-x http://user:password@Your-Ip-Here:Port url

curl -x <[protocol://][user:password@]proxyhost[:port]> url

--proxy <[protocol://][user:password@]proxyhost[:port]> url

--proxy http://user:password@Your-Ip-Here:Port url

-x http://user:password@Your-Ip-Here:Port url

Linux使用curl 命令实现代理访问演示

首先设置http_proxy：

## proxy server, 202.54.1.1, port: 3128, user: foo, password: bar ##
export http_proxy=http://foo:bar@202.54.1.1:3128/
export https_proxy=$http_proxy
## Use the curl command ##
curl -I https://www.cyberciti.biz
curl -v -I https://www.cyberciti.biz

## proxy server, 202.54.1.1, port: 3128, user: foo, password: bar ##

export http_proxy=http://foo:bar@202.54.1.1:3128/

export https_proxy=$http_proxy

## Use the curl command ##

curl -I https://www.cyberciti.biz

curl -v -I https://www.cyberciti.biz

示例输出：

* Rebuilt URL to: www.cyberciti.biz/
*   Trying 202.54.1.1...
* Connected to 1202.54.1.1 (202.54.1.1) port 3128 (#0)
* Proxy auth using Basic with user 'foo'
> HEAD HTTP://www.cyberciti.biz/ HTTP/1.1
> Host: www.cyberciti.biz
> Proxy-Authorization: Basic x9VuUml2xm0vdg93MtIz
> User-Agent: curl/7.43.0
> Accept: */*
> Proxy-Connection: Keep-Alive
> 
< HTTP/1.1 200 OK
HTTP/1.1 200 OK
< Server: nginx
Server: nginx
< Date: Sun, 17 Jan 2016 11:49:21 GMT
Date: Sun, 17 Jan 2016 11:49:21 GMT
< Content-Type: text/html; charset=UTF-8
Content-Type: text/html; charset=UTF-8
< Vary: Accept-Encoding
Vary: Accept-Encoding
< X-Whom: Dyno-l1-com-cyber
X-Whom: Dyno-l1-com-cyber
< Vary: Cookie
Vary: Cookie
< Link: <http://www.cyberciti.biz/wp-json/>; rel="https://api.w.org/"
Link: <http://www.cyberciti.biz/wp-json/>; rel="https://api.w.org/"
< X-Frame-Options: SAMEORIGIN
X-Frame-Options: SAMEORIGIN
< X-Content-Type-Options: nosniff
X-Content-Type-Options: nosniff
< X-XSS-Protection: 1; mode=block
X-XSS-Protection: 1; mode=block
< X-Cache: MISS from server1
X-Cache: MISS from server1
< X-Cache-Lookup: MISS from server1:3128
X-Cache-Lookup: MISS from server1:3128
< Connection: keep-alive
Connection: keep-alive
 
< 
* Connection #0 to host 10.12.249.194 left intact

* Rebuilt URL to: www.cyberciti.biz/

* Trying 202.54.1.1...

* Connected to 1202.54.1.1 (202.54.1.1) port 3128 (#0)

* Proxy auth using Basic with user 'foo'

> HEAD HTTP://www.cyberciti.biz/ HTTP/1.1

> Host: www.cyberciti.biz

> Proxy-Authorization: Basic x9VuUml2xm0vdg93MtIz

> User-Agent: curl/7.43.0

> Accept: */*

> Proxy-Connection: Keep-Alive

< HTTP/1.1 200 OK

HTTP/1.1 200 OK

< Server: nginx

Server: nginx

< Date: Sun, 17 Jan 2016 11:49:21 GMT

Date: Sun, 17 Jan 2016 11:49:21 GMT

< Content-Type: text/html; charset=UTF-8

Content-Type: text/html; charset=UTF-8

< Vary: Accept-Encoding

Vary: Accept-Encoding

< X-Whom: Dyno-l1-com-cyber

X-Whom: Dyno-l1-com-cyber

< Vary: Cookie

Vary: Cookie

< Link: <http://www.cyberciti.biz/wp-json/>; rel="https://api.w.org/"

Link: <http://www.cyberciti.biz/wp-json/>; rel="https://api.w.org/"

< X-Frame-Options: SAMEORIGIN

X-Frame-Options: SAMEORIGIN

< X-Content-Type-Options: nosniff

X-Content-Type-Options: nosniff

< X-XSS-Protection: 1; mode=block

X-XSS-Protection: 1; mode=block

< X-Cache: MISS from server1

X-Cache: MISS from server1

< X-Cache-Lookup: MISS from server1:3128

X-Cache-Lookup: MISS from server1:3128

< Connection: keep-alive

Connection: keep-alive

* Connection #0 to host 10.12.249.194 left intact

在接下来这个例子中，我将下载一个pdf文件：

$ export http_proxy="vivek:myPasswordHere@10.12.249.194:3128/"
$ curl -v -O http://dl.cyberciti.biz/pdfdownloads/b8bf71be9da19d3feeee27a0a6960cb3/569b7f08/cms/631.pdf

1 2	$ export http_proxy="vivek:myPasswordHere@10.12.249.194:3128/" $ curl -v -O http://dl.cyberciti.biz/pdfdownloads/b8bf71be9da19d3feeee27a0a6960cb3/569b7f08/cms/631.pdf

或者使用-x选项：

curl -x 'http://vivek:myPasswordHere@10.12.249.194:3128' -v -O https://dl.cyberciti.biz/pdfdownloads/b8bf71be9da19d3feeee27a0a6960cb3/569b7f08/cms/631.pdf

1	curl -x 'http://vivek:myPasswordHere@10.12.249.194:3128' -v -O https://dl.cyberciti.biz/pdfdownloads/b8bf71be9da19d3feeee27a0a6960cb3/569b7f08/cms/631.pdf

示例输出：

如何在Unix上通过curl使用指定代理服务器

$ curl -x http://prox_server_vpn:3128/ -I https://www.cyberciti.biz/faq/howto-nginx-customizing-404-403-error-page/

1	$ curl -x http://prox_server_vpn:3128/ -I https://www.cyberciti.biz/faq/howto-nginx-customizing-404-403-error-page/

如何使用socks协议

语法和http/https代理是一样的：

curl -x socks5://[user:password@]proxyhost[:port]/ url
curl --socks5 192.168.1.254:3099 https://www.cyberciti.biz/

1 2	curl -x socks5://[user:password@]proxyhost[:port]/ url curl --socks5 192.168.1.254:3099 https://www.cyberciti.biz/

如何配置并设置curl使其代理永久生效

使用 vim 等文本编辑器更新/编辑~/.curlrc 文件：

$ vi ~/.curlrc

1	$ vi ~/.curlrc

追加以下内容：

proxy = server1.cyberciti.biz:3128
proxy-user = "foo:bar"

1 2	proxy = server1.cyberciti.biz:3128 proxy-user = "foo:bar"

保存并关闭文件。另一种方式是在 ~/.bashrc 文件中创建一个别名：

## alias for curl command 
## set proxy-server and port, the syntax is
## alias curl="curl -x {your_proxy_host}:{proxy_port}"
alias curl="curl -x server1.cyberciti.biz:3128"

## alias for curl command

## set proxy-server and port, the syntax is

## alias curl="curl -x {your_proxy_host}:{proxy_port}"

alias curl="curl -x server1.cyberciti.biz:3128"

需要记住的是，代理字符串中可以通过protocol://前缀来指定不同的代理协议。通过socks4://、socks4a://、socks5://或socks5h://指定所使用的 SOCKS 版本。未指定代理协议的情况下，http:// 和其他所有协议都将被默认视为 HTTP 代理。如果代理字符串中未指定端口号，则默认为 1080。-x 选项将会覆盖环境变量中现有的代理设置。如果环境变量中已经设置了代理，用户可以通过将代理设置为""来进行覆盖。更多信息请参阅curl命令手册。