Fetch API proxy IP call: Fetch API proxy call tutorial

First, proxy IP in the end can do what?

Many people do not understand the actual use of proxy IP, in fact, this thing with the courier brother to help you pick up packages like. For example, when you use the Fetch API to do data capture, the site found that you frequently visit, directly to your IP shut down the small black house. At this time to change a proxy IP, equivalent to change a vest to continue to work.

A real case: an e-commerce company needs to monitor the price of competing products in real time, using their own servers to catch directly, less than half an hour to be blocked. After switching to a dynamic residential IP pool, the IP address is automatically switched every hour, and it was fine for three days in a row.

// Example of a basic Fetch request
fetch('https://目标网站.com/api')
  .then(response => response.json())
  .then(data => console.log(data));

Second, hand to teach you in the Fetch set of agents

Here is a pitfall to note: the browser environment Fetch does not support the direct setting of the proxy, you have to use the Node.js environment with the node-fetch library. Specific operation in three steps:

Step 1: Installation of Essential Toolkit

npm install node-fetch @vitalets/google-translate-api

Step 2: Configure proxy parameters (using ipipgo's Socks5 proxy as an example)

const fetch = require('node-fetch');
const { HttpsProxyAgent } = require('https-proxy-agent');

const agent = new HttpsProxyAgent('socks5://用户名:密码@gateway.ipipgo.com:端口号');

fetch('https://目标网站.com', {
  agent.
  headers: { 'User-Agent': 'Mozilla/5.0' }
});

Step 3: Don't be lazy about exception handling

It is recommended to add a retry mechanism to pause for 5 seconds when encountering a 429 status code and try again. ipipgo's API return header will have a remaining quota prompt, remember to handle this parameter.

III. Guide to avoiding pitfalls in real-world scenarios

Here are a few places where newbies often fall head over heels:

IV. First aid kit for common problems

Q: Why doesn't my proxy setting work?
A: First take the curl command to test proxy connectivity:curl -x socks5://proxy address -L destination URLIf you can't, you'll have to add a certificate to the agent configuration. If it passes but the code doesn't work, it's probably a certificate problem, so add it to the agent configurationrejectUnauthorized: false

Q: What should I do if the latency of overseas websites is too high?
A: change into ipipgo cross-border line, measured Hong Kong to the United States can pressure to 200ms or less. Don't be cheap and use a free proxy, the speed can be anxious to death.

Fifth, choose the right package to save heart and money

Here's the official recommended program directly from ipipgo:

• Dynamic residential (standard): Suitable for small and medium-sized crawlers, $7.67/GB is really not expensive!
• Static homes: Do account registration to raise the number of essential, 35 bucks can guarantee a month of stable
• Enterprise Dynamics: with IP rotation policy, automatic switching of time zone parameters

Lastly, a piece of cold knowledge: remember to randomize the request intervals when using proxy IPs, don't be as punctual as a robot. ipipgo client has a built-in random delay function, which is much less troublesome than writing your own setTimeout.