curl命令介绍与使用

curl，全称CommandLine URL 或 CommandLine Uniform Resource Locator，顾名思义，curl命令是在命令行方式下工作，利用URL的语法进行数据的传输或者文件的传输。

这个命令行工具现在多用于Unix和Linux操作系统，是一个开源的工具，功能十分强大。

下面是crul的官方网站，我们可以该网站获取该工具的最新版本，还有最全面的使用方法。

https://curl.haxx.se/
从官网我们可以知道，该工具支持以下30多种类型的传输方式，这当中包含多种协议。

DICT, FILE, FTP, FTPS, Gopher, HTTP, HTTPS, IMAP, IMAPS, LDAP, LDAPS, POP3, POP3S, RTMP, RTSP, SCP, SFTP, SMB, SMBS, SMTP, SMTPS, Telnet and TFTP. curl supports SSL certificates, HTTP POST, HTTP PUT, FTP uploading, HTTP form based upload, proxies, HTTP/2, cookies, user+password authentication (Basic, Plain, Digest, CRAM-MD5, NTLM, Negotiate and Kerberos), file transfer resume, proxy tunneling
最常使用的有FILE、FTP、HTTP、HTTPS等协议。

对于程序员在说，在我们开发远程服务的时候，比如http传输，SOCKET等网络编程时，这个工具能非常方便的作为你的验证工具和测试工具。

比如下面是最简单的用法，通过这种方式获取一个页面。我输入的www.baidu.com甚至还不是一个完整的URL，因为没有指明所用的协议，curl智能地进行了选择。

运行后，返回的是一个百度主页的HTML代码。

curl www.baidu.com

本文主要还是介绍curl的一般用法，详细用法请参阅官网。

前言

curl是利用URL语法在命令行方式下工作的开源文件传输工具。它被广泛应用在Unix、多种Linux发行版中，并且有DOS和Win32、Win64下的移植版本。在日常的开发和问题处理中，经常会使用curl命令来测试http接口，Windows/macOS环境上有很多接口测试的工具比如Postman，但这些工具在Linux平台上使用起来相对不那么便捷。有时候当我们要测试一些外部接口时，当本地无权调用测试路径时，需要将测试建立在Linux平台，除了封装简单的请求代码进行实现外，可通过curl工具实现。当然我们平时接触curl命令最多的地方还是在Linux环境，本来curl作为常用命令应该不用多介绍，但是在使用Jenkins API做数据迁移的过程中发现自己对curl相关的命令还是不熟悉，借这个机会重新梳理一些技巧。

curl简介

curl is a tool to transfer data from or to a server, using one of the supported protocols (DICT, FILE, FTP, FTPS, GOPHER, HTTP, HTTPS, IMAP, IMAPS, LDAP, LDAPS, POP3, POP3S, RTMP, RTSP, SCP, SFTP, SMB, SMBS, SMTP, SMTPS, TELNET and TFTP). The command is designed to work without user interaction.

curl offers a busload of useful tricks like proxy support, user authentication, FTP upload, HTTP post, SSL connections, cookies, file transfer resume, Metalink, and more. As you will see below, the number of features will make your head spin!

curl 支持你做很多事情。你可以把 curl 想象成一个精简的命令行网页浏览器。它支持几乎你能想到的所有协议，可以交互访问几乎所有在线内容。唯一和浏览器不同的是，curl 不会渲染接收到的相应信息。

curl常用命令

curl 是一个利用URL语法在命令行下工作的文件传输工具。它支持文件上传和下载，所以是综合传输工具，但按传统，习惯称 curl 为下载工具。其语法格式及常见参数含义如下，

# 语法
curl [option] [url]# 最简单的使用，获取服务器内容，默认将输出打印到标准输出中(STDOUT)中。
curl http://www.centos.org# 添加-v参数可以看到详细解析过程，通常用于debug
curl -v http://www.centos.org# curl发送Get请求
curl URL
curl URL -O 文件绝对路径# curl发送post请求# 请求主体用json格式
curl -X POST -H 'content-type: application/json' -d @json文件绝对路径 URL
curl -X POST -H 'content-type: application/json' -d 'json内容' URL
# 请求主体用xml格式
curl -X POST -H 'content-type: application/xml' -d @xml文件绝对路径 URL
curl -X POST -H 'content-type: application/xml' -d 'xml内容' URL# 设置cookies
curl URL --cookie "cookie内容"
curl URL --cookie-jar cookie文件绝对路径# 设置代理字符串
curl URL --user-agent "代理内容"
curl URL -A "代理内容"# curl限制带宽
curl URL --limit-rate 速度# curl认证
curl -u user:pwd URL
curl -u user URL# 只打印http头部信息
curl -I URL
curl -head URL# 末尾参数
--progress  显示进度条
--silent    不现实进度条# 不需要修改/etc/hosts，curl直接解析ip请求域名
# 将 http://example.com 或 https://example.com 请求指定域名解析的IP为127.0.0.1
curl --resolve example.com:80:127.0.0.1 http://example.com/
curl --resolve example.com:443:127.0.0.1 https://example.com/

curl接口测试

curl 可以很方便地完成对 REST API 的调用场景，比如：设置 Header，指定 HTTP 请求方法，指定 HTTP 消息体，指定权限认证信息等。通过 -v 选项也能输出 REST 请求的所有返回信息。curl 功能很强大，有很多参数，这里列出 REST 测试常用的参数：

-X/--request [GET|POST|PUT|DELETE|…]  指定请求的 HTTP 方法
-H/--header                           指定请求的 HTTP Header
-d/--data                             指定请求的 HTTP 消息体（Body）
-v/--verbose                          输出详细的返回信息
-u/--user                             指定账号、密码
-b/--cookie                           读取 cookie  # 典型的测试命令为：
curl -v -X POST -H "Content-Type: application/json" http://127.0.0.1:8080/user -d'{"username":"admin","password":"admin1234"}'...# 测试get请求
curl http://www.linuxidc.com/login.cgi?user=test001&password=123456# 测试post请求
curl -d "user=nickwolfe&password=12345" http://www.linuxidc.com/login.cgi# 请求主体用json格式
curl -X POST -H 'content-type: application/json' -d @json文件绝对路径 URL
curl -X POST -H 'content-type: application/json' -d 'json内容' URL# 请求主体用xml格式
curl -X POST -H 'content-type: application/xml' -d @xml文件绝对路径 URL
curl -X POST -H 'content-type: application/xml' -d 'xml内容' URL# 发送post请求时需要使用-X选项，除了使用POST外，还可以使用http规范定义的其它请求谓词，如PUT,DELETE等
curl -XPOST url#发送post请求时，通常需要指定请求体数据。可以使用-d或--data来指定发送的请求体。
curl -XPOST -d "name=leo&age=12" url# 如果需要对请求数据进行urlencode,可以使用下面的方式：
curl -XPOST --data-urlencode "name=leo&age=12" url# 此外发送post请求还可以有如下几种子选项：
–data-raw
–data-ascii
–data-binary

使用curl和Jenkins REST API

# To retrieve the job config.xml
curl -X GET '<jenkinshost>/job/<jobname>/config.xml' -u username:API_TOKEN -o <jobname>.xml# to use this config to create a new job
curl -s -XPOST '<jenkinshost>/createItem?name=<jobname>' -u username:API_TOKEN --data-binary @<jobname>.xml -H "Content-Type:text/xml"# get all jenkins jobs
curl -X GET '<jenkinshost>/api/json?pretty=true' -u username:API_TOKEN -o jobs.json# get jenkins view
curl -X GET '<jenkinshost>/view/<viewname>/api/json' -u username:API_TOKEN -o view.json

curl help

curl --help
Usage: curl [options...] <url>
Options: (H) means HTTP/HTTPS only, (F) means FTP only--anyauth       Pick "any" authentication method (H)-a, --append        Append to target file when uploading (F/SFTP)--basic         Use HTTP Basic Authentication (H)--cacert FILE   CA certificate to verify peer against (SSL)--capath DIR    CA directory to verify peer against (SSL)-E, --cert CERT[:PASSWD]  Client certificate file and password (SSL)--cert-status   Verify the status of the server certificate (SSL)--cert-type TYPE  Certificate file type (DER/PEM/ENG) (SSL)--ciphers LIST  SSL ciphers to use (SSL)--compressed    Request compressed response (using deflate or gzip)-K, --config FILE   Read config from FILE--connect-timeout SECONDS  Maximum time allowed for connection--connect-to HOST1:PORT1:HOST2:PORT2 Connect to host (network level)-C, --continue-at OFFSET  Resumed transfer OFFSET-b, --cookie STRING/FILE  Read cookies from STRING/FILE (H)-c, --cookie-jar FILE  Write cookies to FILE after operation (H)--create-dirs   Create necessary local directory hierarchy--crlf          Convert LF to CRLF in upload--crlfile FILE  Get a CRL list in PEM format from the given file-d, --data DATA     HTTP POST data (H)--data-raw DATA  HTTP POST data, '@' allowed (H)--data-ascii DATA  HTTP POST ASCII data (H)--data-binary DATA  HTTP POST binary data (H)--data-urlencode DATA  HTTP POST data url encoded (H)--delegation STRING  GSS-API delegation permission--digest        Use HTTP Digest Authentication (H)--disable-eprt  Inhibit using EPRT or LPRT (F)--disable-epsv  Inhibit using EPSV (F)--dns-servers   DNS server addrs to use: 1.1.1.1;2.2.2.2--dns-interface  Interface to use for DNS requests--dns-ipv4-addr  IPv4 address to use for DNS requests, dot notation--dns-ipv6-addr  IPv6 address to use for DNS requests, dot notation-D, --dump-header FILE  Write the received headers to FILE--egd-file FILE  EGD socket path for random data (SSL)--engine ENGINE  Crypto engine (use "--engine list" for list) (SSL)--expect100-timeout SECONDS How long to wait for 100-continue (H)-f, --fail          Fail silently (no output at all) on HTTP errors (H)--fail-early    Fail on first transfer error, do not continue--false-start   Enable TLS False Start.-F, --form CONTENT  Specify HTTP multipart POST data (H)--form-string STRING  Specify HTTP multipart POST data (H)--ftp-account DATA  Account data string (F)--ftp-alternative-to-user COMMAND  String to replace "USER [name]" (F)--ftp-create-dirs  Create the remote dirs if not present (F)--ftp-method [MULTICWD/NOCWD/SINGLECWD]  Control CWD usage (F)--ftp-pasv      Use PASV/EPSV instead of PORT (F)-P, --ftp-port ADR  Use PORT with given address instead of PASV (F)--ftp-skip-pasv-ip  Skip the IP address for PASV (F)--ftp-pret      Send PRET before PASV (for drftpd) (F)--ftp-ssl-ccc   Send CCC after authenticating (F)--ftp-ssl-ccc-mode ACTIVE/PASSIVE  Set CCC mode (F)--ftp-ssl-control  Require SSL/TLS for FTP login, clear for transfer (F)-G, --get           Send the -d data with a HTTP GET (H)-g, --globoff       Disable URL sequences and ranges using {} and []-H, --header LINE   Pass custom header LINE to server (H)-I, --head          Show document info only-h, --help          This help text--hostpubmd5 MD5  Hex-encoded MD5 string of the host public key. (SSH)-0, --http1.0       Use HTTP 1.0 (H)--http1.1       Use HTTP 1.1 (H)--http2         Use HTTP 2 (H)--http2-prior-knowledge  Use HTTP 2 without HTTP/1.1 Upgrade (H)--ignore-content-length  Ignore the HTTP Content-Length header-i, --include       Include protocol headers in the output (H/F)-k, --insecure      Allow connections to SSL sites without certs (H)--interface INTERFACE  Use network INTERFACE (or address)-4, --ipv4          Resolve name to IPv4 address-6, --ipv6          Resolve name to IPv6 address-j, --junk-session-cookies  Ignore session cookies read from file (H)--keepalive-time SECONDS  Wait SECONDS between keepalive probes--key KEY       Private key file name (SSL/SSH)--key-type TYPE  Private key file type (DER/PEM/ENG) (SSL)--krb LEVEL     Enable Kerberos with security LEVEL (F)--libcurl FILE  Dump libcurl equivalent code of this command line--limit-rate RATE  Limit transfer speed to RATE-l, --list-only     List only mode (F/POP3)--local-port RANGE  Force use of RANGE for local port numbers-L, --location      Follow redirects (H)--location-trusted  Like '--location', and send auth to other hosts (H)--login-options OPTIONS  Server login options (IMAP, POP3, SMTP)-M, --manual        Display the full manual--mail-from FROM  Mail from this address (SMTP)--mail-rcpt TO  Mail to this/these addresses (SMTP)--mail-auth AUTH  Originator address of the original email (SMTP)--max-filesize BYTES  Maximum file size to download (H/F)--max-redirs NUM  Maximum number of redirects allowed (H)-m, --max-time SECONDS  Maximum time allowed for the transfer--metalink      Process given URLs as metalink XML file--negotiate     Use HTTP Negotiate (SPNEGO) authentication (H)-n, --netrc         Must read .netrc for user name and password--netrc-optional  Use either .netrc or URL; overrides -n--netrc-file FILE  Specify FILE for netrc-:, --next          Allows the following URL to use a separate set of options--no-alpn       Disable the ALPN TLS extension (H)-N, --no-buffer     Disable buffering of the output stream--no-keepalive  Disable keepalive use on the connection--no-npn        Disable the NPN TLS extension (H)--no-sessionid  Disable SSL session-ID reusing (SSL)--noproxy       List of hosts which do not use proxy--ntlm          Use HTTP NTLM authentication (H)--ntlm-wb       Use HTTP NTLM authentication with winbind (H)--oauth2-bearer TOKEN  OAuth 2 Bearer Token (IMAP, POP3, SMTP)-o, --output FILE   Write to FILE instead of stdout--pass PASS     Pass phrase for the private key (SSL/SSH)--path-as-is    Do not squash .. sequences in URL path--pinnedpubkey FILE/HASHES Public key to verify peer against (SSL)--post301       Do not switch to GET after following a 301 redirect (H)--post302       Do not switch to GET after following a 302 redirect (H)--post303       Do not switch to GET after following a 303 redirect (H)--preproxy [PROTOCOL://]HOST[:PORT] Proxy before HTTP(S) proxy-#, --progress-bar  Display transfer progress as a progress bar--proto PROTOCOLS  Enable/disable PROTOCOLS--proto-default PROTOCOL  Use PROTOCOL for any URL missing a scheme--proto-redir PROTOCOLS   Enable/disable PROTOCOLS on redirect-x, --proxy [PROTOCOL://]HOST[:PORT]  Use proxy on given port--proxy-anyauth  Pick "any" proxy authentication method (H)--proxy-basic   Use Basic authentication on the proxy (H)--proxy-digest  Use Digest authentication on the proxy (H)--proxy-cacert FILE CA certificate to verify peer against for proxy (SSL)--proxy-capath DIR CA directory to verify peer against for proxy (SSL)--proxy-cert CERT[:PASSWD] Client certificate file and password for proxy (SSL)--proxy-cert-type TYPE Certificate file type (DER/PEM/ENG) for proxy (SSL)--proxy-ciphers LIST SSL ciphers to use for proxy (SSL)--proxy-crlfile FILE Get a CRL list in PEM format from the given file for proxy--proxy-insecure Allow connections to SSL sites without certs for proxy (H)--proxy-key KEY Private key file name for proxy (SSL)--proxy-key-type TYPE Private key file type for proxy (DER/PEM/ENG) (SSL)--proxy-negotiate  Use HTTP Negotiate (SPNEGO) authentication on the proxy (H)--proxy-ntlm    Use NTLM authentication on the proxy (H)--proxy-header LINE Pass custom header LINE to proxy (H)--proxy-pass PASS Pass phrase for the private key for proxy (SSL)--proxy-ssl-allow-beast Allow security flaw to improve interop for proxy (SSL)--proxy-tlsv1   Use TLSv1 for proxy (SSL)--proxy-tlsuser USER TLS username for proxy--proxy-tlspassword STRING TLS password for proxy--proxy-tlsauthtype STRING TLS authentication type for proxy (default SRP)--proxy-service-name NAME  SPNEGO proxy service name--service-name NAME  SPNEGO service name-U, --proxy-user USER[:PASSWORD]  Proxy user and password--proxy1.0 HOST[:PORT]  Use HTTP/1.0 proxy on given port-p, --proxytunnel   Operate through a HTTP proxy tunnel (using CONNECT)--pubkey KEY    Public key file name (SSH)-Q, --quote CMD     Send command(s) to server before transfer (F/SFTP)--random-file FILE  File for reading random data from (SSL)-r, --range RANGE   Retrieve only the bytes within RANGE--raw           Do HTTP "raw"; no transfer decoding (H)-e, --referer       Referer URL (H)-J, --remote-header-name  Use the header-provided filename (H)-O, --remote-name   Write output to a file named as the remote file--remote-name-all  Use the remote file name for all URLs-R, --remote-time   Set the remote file's time on the local output-X, --request COMMAND  Specify request command to use--resolve HOST:PORT:ADDRESS  Force resolve of HOST:PORT to ADDRESS--retry NUM   Retry request NUM times if transient problems occur--retry-connrefused  Retry on connection refused (use with --retry)--retry-delay SECONDS  Wait SECONDS between retries--retry-max-time SECONDS  Retry only within this period--sasl-ir       Enable initial response in SASL authentication-S, --show-error    Show error. With -s, make curl show errors when they occur-s, --silent        Silent mode (don't output anything)--socks4 HOST[:PORT]  SOCKS4 proxy on given host + port--socks4a HOST[:PORT]  SOCKS4a proxy on given host + port--socks5 HOST[:PORT]  SOCKS5 proxy on given host + port--socks5-hostname HOST[:PORT]  SOCKS5 proxy, pass host name to proxy--socks5-gssapi-service NAME  SOCKS5 proxy service name for GSS-API--socks5-gssapi-nec  Compatibility with NEC SOCKS5 server-Y, --speed-limit RATE  Stop transfers below RATE for 'speed-time' secs-y, --speed-time SECONDS  Trigger 'speed-limit' abort after SECONDS (default: 30)--ssl           Try SSL/TLS (FTP, IMAP, POP3, SMTP)--ssl-reqd      Require SSL/TLS (FTP, IMAP, POP3, SMTP)-2, --sslv2         Use SSLv2 (SSL)-3, --sslv3         Use SSLv3 (SSL)--ssl-allow-beast  Allow security flaw to improve interop (SSL)--ssl-no-revoke    Disable cert revocation checks (WinSSL)--stderr FILE   Where to redirect stderr (use "-" for stdout)--suppress-connect-headers  Suppress proxy CONNECT response headers--tcp-nodelay   Use the TCP_NODELAY option--tcp-fastopen  Use TCP Fast Open-t, --telnet-option OPT=VAL  Set telnet option--tftp-blksize VALUE  Set TFTP BLKSIZE option (must be >512)--tftp-no-options  Do not send TFTP options requests-z, --time-cond TIME   Transfer based on a time condition-1, --tlsv1         Use >= TLSv1 (SSL)--tlsv1.0       Use TLSv1.0 (SSL)--tlsv1.1       Use TLSv1.1 (SSL)--tlsv1.2       Use TLSv1.2 (SSL)--tlsv1.3       Use TLSv1.3 (SSL)--tls-max VERSION  Use TLS up to VERSION (SSL)--trace FILE    Write a debug trace to FILE--trace-ascii FILE  Like --trace, but without hex output--trace-time    Add time stamps to trace/verbose output--tr-encoding   Request compressed transfer encoding (H)-T, --upload-file FILE  Transfer FILE to destination--url URL       URL to work with-B, --use-ascii     Use ASCII/text transfer-u, --user USER[:PASSWORD]  Server user and password--tlsuser USER  TLS username--tlspassword STRING  TLS password--tlsauthtype STRING  TLS authentication type (default: SRP)--unix-socket PATH    Connect through this Unix domain socket--abstract-unix-socket PATH Connect to an abstract Unix domain socket-A, --user-agent STRING  Send User-Agent STRING to server (H)-v, --verbose       Make the operation more talkative-V, --version       Show version number and quit-w, --write-out FORMAT  Use output FORMAT after completion--xattr         Store metadata in extended file attributes-q, --disable       Disable .curlrc (must be first parameter)