⚡ RapidMatchDomain ⚡

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A fast Lua library to check if a domain name in a list of domain names. Wildcards, subdomains and IP addresses supported. It has O(1) complexity meaning even with 2 million domains it doesn't lag a tiny bit more.

For example the library is ideal for security to see if domains and/or IP addresses are in a blocklist.

Installing

Installing via LuaRocks

Run $ luarocks install rapid-match-domain

Installing via Lit

Work in progess...

Instaling via Wally

Work in progess...

Installing standalone

Work in progess...

Usage

Requiring the library

To require the module use the following Lua code at the top of your script:

local rapidMatch = require("rapid-match-domain")

If you want you can use anything else than rapidMatch as the variable name for the library.

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Initialization of the domain List

The following Lua code initiates an empty table t to store a list of domain names:

local t = {}

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Adding domains to the List

The next piece of code adds the specified domain names to the existing list. This operation can be performed multiple times with different domain lists:

rapidMatch.addUrls(t, domains, true)

Parameters:

• t (table): The table storing the list of domain names.
• domains (table | string): A table or a newline seperated string containing the domain names to be added to the list.
• useSubdomains (boolean?) : A boolean telling if domains being matched againts the list would still match if they have extra subdomains. Default value is true.

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Matching a domain against the List

The final piece of code shows how to check if a domain matches any of the domain names in the list:

if rapidMatch.match(t, "www.example.com") then
-- The domain matches
end

Parameters:

• t (table): The table storing the list of domain names.
• "www.example.com" (string): The domain name to match against the list.

Returns:

• true if the domain matches any entry in the list.
• false if the domain does not match any entry in the list.

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Features

• 🔥 Wildcard support
• 🔍 Matching with and without subdomains
• 🌐 IPv4, full IPv6 addresses and portnumbers supported
• 🌍 Wildcards and subdomain support allow rudimentary IP range checking
• ⚡ Super simple implementation, no bloat, 80 lines of Lua in total
• ⏱️ Amount of domains in the list to be checked againts doesn't increase the complexity, will always be as fast as O(1) amount of domains in the checklist