curl send HTTPPOST | form submit data practice

Teach you how to send POST request with curl proxy.

Brothers engaged in network development must have encountered this situation: they write the form submission script somehow blocked IP, or need to batch test the effect of access to different regions. At this time we have to ask the proxy IP this magic weapon, today we take our family ipipgo proxy service to give a chestnut, teach you how to use curl commands with the proxy IP submit form data.

Why do I have to use a proxy IP?

Take a real scenario: you want to test the loading speed of the website registration function in different regions, you can't really buy a plane ticket to run around, right? This time with ipipgo's dynamic residential IP, 1 minute to change a regional IP, sitting in front of the computer can simulate the national user registration. Another example is to do data collection, hanging on the high stash of agents, the target site simply can not see that you are operating with the machine.

Note the three points:

1. find a reliable proxy service provider (such as ipipgo) to get the API proxy address
2. Test proxy connectivity before formalizing use
3. Frequency of form submissions to resemble real-life operations

The correct posture of curl with proxy

Straight to the hard dishes, assuming you're going to head to http://example.com/submit传登录数据:

curl -x "http://user:pass@proxy.ipipgo.com:8080"
-d "username=test&password=123456"
-X POST http://example.com/submit

here are-x parameteris to specify a proxy server. ipipgo's proxy address format isUsername:Password@Gateway Address:PortThe first thing you need to do is to get the proxy protocols mixed up. Newcomers often make the mistake of confusing the proxy protocol, http proxy and socks5 proxy is written differently, we ipipgo background has a detailed sample code.

Real-world form submission process

Suppose you want to simulate user registration in three steps:

1. Get the latest proxy IP from the ipipgo backend (dynamic residential IP is recommended)
2. Test proxy connectivity: curl -x proxy address -I https://www.baidu.com
3. Formal submission of form data with CAPTCHA:

curl -x "http://user2023:sjYk9P@proxy.ipipgo.com:8899"
-d "mobile=13800138000&smscode=8848&nickname=Iron Egg"
-H "Content-Type: application/x-www-form-urlencoded"
-X POST http://target-site.com/register

Encountering CAPTCHA recognition problems? It is recommended to get the CAPTCHA with local IP first, then hang the proxy to submit, so that the success rate is higher. ipipgo's short-lived proxy is especially suitable for this kind of scenario which needs to change IP frequently.

Pitfalls you may encounter

Q: What can I do if the agent can't connect?
A: First check the whitelist settings, ipipgo need to bind the use of IP. and then test the proxy address and port is not copied wrong, novice often confuse _ and -.

Q: Submission data is blocked by the website?
A: two ways: 1. change ipipgo's high anonymous proxy 2. add User-Agent request header in curl, disguised as a browser access.

Q: What should I do if my agent is slow?
A：选物理距离近的节点，比如目标网站在北京就用华北机房。ipipgo后台可以按筛选节点，别傻乎乎用美国代理访问国内网站。

Why do you recommend ipipgo?

Experience with their own home use: their homeDynamic Residential IP PoolReally solid, did automated tests running for 12 hours straight without dropping out. The best thing is that there areRequest Retry MechanismThis is important for crawler scripts that need to run for a long time.

Recently releasedpay-per-use packageEspecially suitable for small projects, 10 dollars can use 500M traffic, better than those who must pay monthly. Stealing a trick: contact customer service and say the code word "CURL2023″ can receive a 3-day free trial, enough for you to test several projects.

Finally remind everyone: proxy IP is not a place outside the law, do serious business with ipipgo's compliant IP resources, do not move the brain. Form submission frequency control, don't get hung up on people's websites, by then the gods can't save them.