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Version: 8.2511.x.x RR

Helpers

The Helpers.lua module is a collection of helper functions that are helpful for writing LuaFilter scripts.

Helpers.startsWith(stringToCheck, startsWith)​

Checks if a string (first parameter stringToCheck) starts with a given part (second parameter startsWith). Returns with "true", if either the string starts with the given part, or if both stringToCheck and startsWith are nil.

Helpers.endsWith(stringToCheck, endsWith)​

Checks if a string (first parameter stringToCheck) ends with a given part (second parameter endsWith). Returns with "true", if either the string ends with the given part, or if both stringToCheck and endsWith are nil.

Helpers.containsHost(url)​

Checks if a URL contains a schema/host prefix.

Helpers.trim(string)​

Returns a given string, with all leading and trailing whitespaces removed.

local result = Helpers.trim(" some string ")
-- result will contain "some string"

Helpers.getTrimmedLines(string)​

Splits a string into several lines. Returns with a table containing the lines.

local string = "foo bar\nbar foo\n"
local lines = Helpers.getTrimmedLines(string)
-- the table 'lines' will contain two strings, "foo bar" and "bar foo"

Helpers.normalize(uri)​

Normalizes a request URI.

local normalizedUri = Helpers.normalize("/a/b/../index.html")
-- normalizedUri will be "/a/index.html"

Helpers.noCase(string)​

Changes any character "x" in a string (both lower and upper case) into the pattern [xX]. Useful for case-insensitive search.

Helpers.tableLength(tab)​

Returns the number of table entries.

local table = {'some', 'string'}
local counter = Helpers.tableLength(table)
-- counter will be '2'

Helpers.luaEscape(string)​

Escapes every lua regex special character so that it can be used inside a lua regex.