Short Link Analysis

Oct 24, 2024#项目分析98

AI Translation

This post is translated from Chinese into English through AI.View Original

AI-generated summary

In most scenarios, long connections are used, leading to the creation of short links for various purposes, such as character limits on messaging platforms. **Short Link Generation:** 1. Using hash algorithms. 2. Using an ID generator. Both methods can utilize base algorithms to reduce length. **Hash Algorithm Generation:** This method may encounter hash collisions. The provided code demonstrates generating a short URL using SHA-256 encryption and base58 encoding, which avoids misleading characters. **ID Generator:** Short links can also be created using the Snowflake algorithm for ID generation. **Redirection:** Typically, a 302 redirect is used, as a 301 permanent redirect can leave a cache in the browser, affecting short link usage statistics. **References:** A brief discussion on short link design.

Currently, most scenarios use long connections, which have led to the creation of short links for various purposes (such as character limits on SMS platforms).

Short Link Generation#

Generated through hash algorithms

Generated through a number generator

Both can ultimately reduce length using base algorithms.

Hash Algorithm Generation#

Possible hash collisions

// 1.hash
func GenerateShortenUrl(initUrl, userID string) string {
  // Encrypted with 256
	urlSHA256 := sha256f(initUrl + userID)
	genNum := new(big.Int).SetBytes(urlSHA256).Uint64()
  // Base 58 excludes misleading letters o, O, I, l and +, /
  // Reduces character length
	return base58Encoded([]byte(fmt.Sprintf("%d", genNum)))[0:8]
}

func sha256f(input string) []byte {
	hashed := sha256.Sum256([]byte(input))
	return hashed[:]
}

func base58Encoded(input []byte) string {
	encoded, err := base58.BitcoinEncoding.Encode(input)
	if err != nil {
		fmt.Println(err.Error())
		os.Exit(1)
	}
	return string(encoded)
}

Number Generator Generation#

Generated ID using the Snowflake algorithm.

Redirection#

Generally redirected using 302, while 301 permanent redirection leaves a cache in the browser, making it impossible to gather statistics through short link access.

Reference#

Discussion on Short Link Design