Module:Category handler
Template:Module rating This is the Category handler LUA module which is invoked in a number of MediaWiki-based WIKIs, including the venerable Wikipedia.
Dependencies
The following modules are required:
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-- --
-- CATEGORY HANDLER --
-- --
-- This module implements the {{category handler}} template in Lua, with a few improvements: all --
-- namespaces and all namespace aliases are supported, and namespace names are detected --
-- automatically for the local wiki. This module requires [[Module:Namespace detect]] and --
-- [[Module:Yesno]] to be available on the local wiki. It can be configured for different wikis --
-- by altering the values in the "cfg" table. --
-- --
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-- Configuration data --
-- Language-specific parameter names and values can be set here. --
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local cfg = {}
-- The following config values set the names of parameters that suppress categorisation. They are used
-- with Module:Yesno, and work as follows:
--
-- cfg.nocat:
-- Result of yesno(args[cfg.nocat]) Effect
-- true Categorisation is suppressed
-- false Categorisation is allowed, and the blacklist check is skipped
-- nil Categorisation is allowed
--
-- cfg.categories:
-- Result of yesno(args[cfg.categories]) Effect
-- true Categorisation is allowed, and the blacklist check is skipped
-- false Categorisation is suppressed
-- nil Categorisation is allowed
cfg.nocat = 'nocat'
cfg.categories = 'categories'
-- The parameter name for the legacy "category2" parameter. This skips the blacklist if set to the
-- cfg.category2Yes value, and suppresses categorisation if present but equal to anything other than
-- cfg.category2Yes or cfg.category2Negative.
cfg.category2 = 'category2'
cfg.category2Yes = 'yes'
cfg.category2Negative = '¬'
-- cfg.subpage is the parameter name to specify how to behave on subpages. cfg.subpageNo is the value to
-- specify to not categorise on subpages; cfg.only is the value to specify to only categorise on subpages.
cfg.subpage = 'subpage'
cfg.subpageNo = 'no'
cfg.subpageOnly = 'only'
-- The parameter for data to return in all namespaces.
cfg.all = 'all'
-- The parameter name for data to return if no data is specified for the namespace that is detected. This
-- must be the same as the cfg.other parameter in [[Module:Namespace detect]].
cfg.other = 'other'
-- The parameter name used to specify a page other than the current page; used for testing and
-- demonstration. This must be the same as the cfg.page parameter in [[Module:Namespace detect]].
cfg.page = 'page'
-- The categorisation blacklist. Pages that match Lua patterns in this list will not be categorised.
-- (However, see the explanation of cfg.nocat, cfg.categories and cfg.category2 for some exceptions.)
-- If the namespace name has a space in, it must be written with an underscore, e.g. "Wikipedia_talk".
-- Other parts of the title can have either underscores or spaces.
cfg.blacklist = {
'^Main Page$', -- don't categorise the main page.
-- Don't categorise the following pages or their subpages.
'^Wikipedia:Cascade%-protected items$',
'^Wikipedia:Cascade%-protected items/.*$',
'^User:UBX$', -- The userbox "template" space.
'^User:UBX/.*$',
'^User_talk:UBX$',
'^User_talk:UBX/.*$',
-- Don't categorise subpages of these pages, but allow
-- categorisation of the base page.
'^Wikipedia:Template messages/.+$',
'/[aA]rchive' -- Don't categorise archives.
}
-- This is a table of namespaces to categorise by default. They should be in the format of parameter
-- names accepted by [[Module:Namespace detect]].
cfg.defaultNamespaces = {
'main',
'file',
'help',
'category'
}
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-- End configuration data --
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-- Get dependent modules
local nsDetect = require('Module:Namespace detect')
local yesno = require('Module:Yesno')
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-- Local functions --
-- The following are internal functions, which we do not want to be accessible from other modules. --
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-- Find whether we need to return a category or not.
local function needsCategory(pageObject, args)
-- Don't categorise if the relevant options are set.
if yesno(args[cfg.nocat])
or yesno(args[cfg.categories]) == false
or (
args[cfg.category2]
and args[cfg.category2] ~= cfg.category2Yes
and args[cfg.category2] ~= cfg.category2Negative
)
then
return false
end
-- If there is no pageObject available, then that either means that we are over
-- the expensive function limit or that the title specified was invalid. Invalid
-- titles will probably only be a problem during testing, so we choose the best
-- fallback for being over the expensive function limit. The fallback behaviour
-- of the old template was to assume the page was not a subpage, so we will do
-- the same here.
if args[cfg.subpage] == cfg.subpageNo and pageObject and pageObject.isSubpage then
return false
end
if args[cfg.subpage] == cfg.subpageOnly
and (not pageObject or (pageObject and not pageObject.isSubpage))
then
return false
end
return true
end
-- Find whether we need to check the blacklist or not.
local function needsBlacklistCheck(args)
if yesno(args[cfg.nocat]) == false
or yesno(args[cfg.categories]) == true
or args[cfg.category2] == cfg.category2Yes
then
return false
else
return true
end
end
-- Find whether any namespace parameters have been specified.
-- Mappings is the table of parameter mappings taken from
-- [[Module:Namespace detect]].
local function nsParamsExist(mappings, args)
if args[cfg.all] or args[cfg.other] then
return true
end
for ns, params in pairs(mappings) do
for i, param in ipairs(params) do
if args[param] then
return true
end
end
end
return false
end
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-- Global functions --
-- The following functions are global, because we want them to be accessible from #invoke and --
-- from other Lua modules. --
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local p = {}
-- Find if a string matches the blacklist. Returns the match if one is found, or nil otherwise.
-- Input should be a page title with a namespace prefix, e.g. "Wikipedia talk:Articles for deletion".
function p.matchesBlacklist(page)
if type(page) ~= 'string' then return end
for i, pattern in ipairs(cfg.blacklist) do
local match = mw.ustring.match(page, pattern)
if match then
return match
end
end
end
-- The main structure of the module. Checks whether we need to categorise,
-- and then passes the relevant arguments to [[Module:Namespace detect]].
function p._main(args)
-- Get the page object and argument mappings from
-- [[Module:Namespace detect]], to save us from having to rewrite the
-- code.
local pageObject = nsDetect.getPageObject(args[cfg.page])
local mappings = nsDetect.getParamMappings()
if not needsCategory(pageObject, args) then return end
local ret = ''
-- Check blacklist if necessary.
if not needsBlacklistCheck(args) or not p.matchesBlacklist(pageObject.prefixedText) then
if not nsParamsExist(mappings, args) then
-- No namespace parameters exist; basic usage. Pass args[1] to
-- [[Module:Namespace detect]] using the default namespace
-- parameters, and return the result.
local ndargs = {}
for _, ndarg in ipairs(cfg.defaultNamespaces) do
ndargs[ndarg] = args[1]
end
ndargs.page = args.page
ndargs.demospace = args.demospace
local ndresult = nsDetect.main(ndargs)
if ndresult then
ret = ret .. ndresult
end
else
-- Namespace parameters exist; advanced usage.
-- If the all parameter is specified, return it.
local all = args.all
if type(all) == 'string' then
ret = ret .. all
end
-- Get the arguments to pass to [[Module:Namespace detect]].
local ndargs = {}
for ns, params in pairs(mappings) do
for _, param in ipairs(params) do
ndargs[param] = args[param] or args[cfg.other] or nil
end
end
ndargs.other = args.other
ndargs.page = args.page
ndargs.demospace = args.demospace
local data = nsDetect.main(ndargs)
-- Work out what to return based on the result of the namespace detect call.
local datanum = tonumber(data)
if type(datanum) == 'number' then
-- "data" is a number, so return that positional parameter.
-- Remove non-positive integer values, as only positive integers
-- from 1-10 were used with the old template.
if datanum > 0 and math.floor(datanum) == datanum then
local dataArg = args[datanum]
if type(dataArg) == 'string' then
ret = ret .. dataArg
end
end
else
-- "data" is not a number, so return it as it is.
if type(data) == 'string' then
ret = ret .. data
end
end
end
end
return ret
end
function p.main(frame)
-- If called via #invoke, use the args passed into the invoking
-- template, or the args passed to #invoke if any exist. Otherwise
-- assume args are being passed directly in.
local origArgs
if frame == mw.getCurrentFrame() then
origArgs = frame:getParent().args
for k, v in pairs(frame.args) do
origArgs = frame.args
break
end
else
origArgs = frame
end
-- Trim whitespace and remove blank arguments for the following args:
-- 1, 2, 3 etc., "nocat", "categories", "subpage", and "page".
local args = {}
for k, v in pairs(origArgs) do
if type(v) == 'string' then
v = mw.text.trim(v) -- Trim whitespace.
end
if type(k) == 'number'
or k == cfg.nocat
or k == cfg.categories
or k == cfg.subpage
or k == cfg.page
then
if v ~= '' then
args[k] = v
end
else
args[k] = v
end
end
-- Lower-case "nocat", "categories", "category2", and "subpage". These
-- parameters are put in lower case whenever they appear in the old
-- template, so we can just do it once here and save ourselves some work.
local lowercase = {cfg.nocat, cfg.categories, cfg.category2, cfg.subpage}
for _, v in ipairs(lowercase) do
local argVal = args[v]
if type(argVal) == 'string' then
args[v] = mw.ustring.lower(argVal)
end
end
return p._main(args)
end
return p