Dump CDB into the current directory using `wget`

dumpcdb.lua

#!/usr/bin/env luajit
-- See https://content.minetest.net/help/api/
local http_request = require"http.request"
local lunajson = require"lunajson"

do
	-- URI escaping utilities
	-- See https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/encodeURI

	local uri_unescaped_chars = {}
	for char in ("-_.!~*'()"):gmatch(".") do
		uri_unescaped_chars[char] = true
	end
	local function add_unescaped_range(from, to)
		for byte = from:byte(), to:byte() do
			uri_unescaped_chars[string.char(byte)] = true
		end
	end
	add_unescaped_range("0", "9")
	add_unescaped_range("a", "z")
	add_unescaped_range("A", "Z")

	local function encode(str, allowed_chars)
		return str:gsub(".", function(char)
			if allowed_chars[char] then
				return char
			end
			return ("%%%02X"):format(char:byte())
		end)
	end

	function string:encode_uri_component()
		return encode(self, uri_unescaped_chars)
	end
end

local function get_body(uri)
	local headers, stream = assert(http_request.new_from_uri(uri):go())
	local body, err = stream:get_body_as_string()
	if not body then
		print(err)
		return
	end
	if headers:get":status" ~= "200" then
	    print(body)
		return
	end
	return body
end
local packages = lunajson.decode(get_body"https://content.minetest.net/api/packages/")
for index, package in ipairs(packages) do
	local path = package.author:encode_uri_component() .. "/" .. package.name
	print("Downloading releases of " .. path .. ": " .. index .. " of " .. #packages)
	local releases = lunajson.decode(get_body("https://content.minetest.net/api/packages/" .. path .. "/releases/"))
	for _, release in ipairs(releases) do
		assert(not (path:find"'" or release.url:find"'" or release.release_date:find"'"))
		os.execute(("mkdir -p '%s'"):format(path))
		os.execute(("wget --tries 10 -P '%s' -O '%s.zip' 'https://content.minetest.net%s'"):format(path, release.release_date, release.url))
	end
end