Module:URL

This Lua module is used in MediaWiki:Titleblacklist-custom-URL.
Changes to it can cause immediate changes to the Wikipedia user interface.
To avoid major disruption, any changes should be tested in the module's /sandbox or /testcases subpages, or in your own module sandbox. The tested changes can be added to this page in a single edit. Please discuss changes on the talk page before implementing them.

This module implements {{URL}} and {{URL2}}. Please see the template page for documentation.

Lua interface

The p._url(url, text, msg) function may be used by other Lua modules. It returns a formatted Wikitext for the given URL, made suitable for line wrapping using . It takes the following parameters:

url: REQUIRED. The URL to format.
text: OPTIONAL. Display text to put in the Wikitext link. Defaults to a pretty version of the URL.
msg: OPTIONAL. String. If content is false, n or N, do not emit a help message (using {{tlx}}) when URL is not given.

Example

The following module emits a prettified link to log the user out. It will wrap correctly to most widths.

local url = require('Module:URL')._url
local p = {}

p.main = function(frame)
    return url("https://en.wikipedia.org/wiki/Special:UserLogout")
end

return p

local p = {}
 
function trim(s)
    if s == nil then return '' end
    return (s:gsub("^%s*(.-)%s*$", "%1"))
end

function startsWith(s, prefix)
    return (s:find(prefix, 1, true)) == 1
end

function split(s, sep) -- string split function for a single-character separator
    local ret = {}
    local n = 1
    for w in s:gmatch("([^" .. sep .. "]*)") do
        ret[n] = ret[n] or w  -- only set once (so the blank after a string is ignored)
        if w == '' then n = n + 1 end -- step forwards on a blank but not a string
    end
    return ret
end

function rest(tbl, start) -- get the elements of the table beginning at the specified starting index
    local ret = {}
    if start > #tbl then
        return ret
    end
    for i = start, #tbl do
        ret[i - start + 1] = tbl[i]
    end
    return ret
end

function p._url(url, text)
    local lcUrl = url:lower()
    if not startsWith(lcUrl, 'http://') and not startsWith(lcUrl, 'https://') and not startsWith(lcUrl, 'ftp://') then
        url = 'http://' .. url
    end
    
    if text == '' then
        local comps = split(url, '/')
        local host = comps[3]:lower()
        local path = table.concat(rest(comps, 4), '/')

        text = host
        if path ~= '' then
            text = text .. '/' .. path
        end
    end
    
    return string.format('<span class="url">[%s %s]</span>', url, text)
end

function p.url(frame)
    local url = trim(frame.args[1])
    local text = trim(frame.args[2])

    if url == '' then
        return frame:expandTemplate{ title = 'tlx', args = { 'URL', "''example.com''", "''optional display text''" } }
    end
    
    return p._url(url, text)
end

return p

Lua interface

Example

See also