curl的使用

curl是一个命令行工具和库，用于通过URL传输数据

支持的通信协议非常多：

　　DICT, FILE, FTP, FTPS, Gopher, HTTP, HTTPS, IMAP, IMAPS, LDAP, LDAPS, MQTT, POP3, POP3S, RTMP, RTMPS, RTSP, SCP, SFTP, SMB, SMBS, SMTP, SMTPS, Telnet and TFTP. curl supports SSL certificates, HTTP POST, HTTP PUT等等

1.安装

Ubuntu上安装

sudo apt install curl

centos上安装

sudo yum install curl

windows上

安装git，Git Bash 自带 cURL 

2.使用

（1）直接请求URL

eg：

$ curl http://wttr.in/

 （2）直接请求URL

-o参数将服务器的回应保存成文件

eg：

$ curl -o aa.txt http://wttr.in/

会将刚才输出的内容，保存到 aa.txt中

保存图片

$ curl -o tmp.png 'https://img2020.cnblogs.com/blog/798214/202006/798214-20200612102237381-1152081887.png'

-s 参数禁用进度表

$ curl -o tmp.png 'https://img2020.cnblogs.com/blog/798214/202006/798214-20200612102237381-1152081887.png' -s

--process-bar 参数让进度表显示为进度条

$ curl -o tmp.png 'https://img2020.cnblogs.com/blog/798214/202006/798214-20200612102237381-1152081887.png' --progress-bar

 -i 参数显示 Response Headers 信息

$  curl -i -X GET  http://localhost:8080/user/detail?id=1 -s
HTTP/1.1 200
Access-Control-Allow-Methods: GET,POST,OPTIONS,PUT,DELETE
Vary: Origin
Vary: Access-Control-Request-Method
Vary: Access-Control-Request-Headers
Content-Type: application/json
Transfer-Encoding: chunked
Date: Mon, 15 Jun 2020 04:34:01 GMT

{"code":200,"message":"SUCCESS","data":{"id":1,"name":"admin","nickName":"超管","email":"admin@qq.com","mobile":"13612345678","status":1}}

-I 只显示 Response Headers 信息

$ curl -I -X GET http://localhost:8080/user/detail?id=1 -s
HTTP/1.1 200
Access-Control-Allow-Methods: GET,POST,OPTIONS,PUT,DELETE
Vary: Origin
Vary: Access-Control-Request-Method
Vary: Access-Control-Request-Headers
Content-Type: application/json
Transfer-Encoding: chunked
Date: Mon, 15 Jun 2020 04:32:13 GMT

-X 指定请求方式

GET

$ curl -X GET http://localhost:8080/user/detail?id=1 -s
{"code":200,"message":"SUCCESS","data":{"id":1,"name":"admin","nickName":"超管","email":"admin@qq.com","mobile":"13612345678","status":1}}

POST

参数为form数据

$ curl -X POST -d "id=1" http://localhost:8080/user/detail -s
{"code":200,"message":"SUCCESS","data":{"id":1,"name":"admin","nickName":"超管","email":"admin@qq.com","mobile":"13612345678","status":1}}

多个参数

$ curl -X POST -d "id=1&change=1" http://localhost:8080/user/detail -s
{"code":200,"message":"SUCCESS","data":{"id":1,"name":"admin","nickName":"超管","email":"admin@qq.com","mobile":"13612345678","status":1}}

参数为json数据

$ curl -H "Content-Type: application/json" -X POST -d '{"name":"abc","nickName":"abc123"}' http://localhost:8080/user/add -s
{"code":200,"message":"SUCCESS","data":{"id":33,"name":"abc","nickName":"abc123","email":null,"mobile":null,"status":null}}

-d或--data用来指定传递的数据

-H用来指定Header，有四种方式

application/x-www-form-urlencoded：默认的形式，即key1=value1&key2=value2的形式
multipart/form-data：使用表单上传文件时使用这个形式
application/json：提交JSON格式的数据
text/xml：提交XML格式的数据

-F参数用来向服务器上传二进制文件

$ curl -H "multipart/form-data" -X POST -F "file=@test.ifc" http://localhost:8080/upload/fullFile -s
{"code":200,"message":"上传成功","data":{"id":14,"name":"20200615122911704.txt","size":15778,"status":1,"uploadTime":"2020-06-15 12:29:11"}}