Module:WikidataIB

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This module is designed specifically to implement a mechanism which moves control of whether Wikidata values are used in an infobox from the template coder at the infobox design level to the editor at the article level. It should only be used inside an infobox.

Usage[edit]

The module provides these calls specifically for use in infoboxes at present:

  1. getValue
  2. getPreferredValue
  3. getSourcedValue
  4. getCoords
  5. getQualifierValue

The call getSourcedValue is kept for backwards compatibility as it is now redundant to getValue which can do the same job using the |onlysourced=true parameter.

There are also these utility calls:

  1. getLink
  2. getLabel
  3. getAT
  4. formatDate
  5. checkBlacklist

Generalised calls:

{{#invoke:WikidataIB |getValue |<PropertyID> |name=<fieldname> |suppressfields=<list of fields which will never display> |fetchwikidata=<list of fields to fetch values from Wikidata> |onlysourced=<yes/no> |noicon=<yes/no> |df=<dmy/mdy/y> |bc=<BC/BCE> |<local parameter>}}
{{#invoke:WikidataIB |getPreferredValue |<PropertyID> |name=<fieldname> |suppressfields=<list of fields which will never display> |fetchwikidata=<list of fields to fetch values from Wikidata> |onlysourced=<yes/no> |noicon=<yes/no> |df=<dmy/mdy/y> |bc=<BC/BCE> |<local parameter>}}
{{#invoke:WikidataIB |getSourcedValue |<PropertyID> |name=<fieldname> |suppressfields=<list of fields which will never display> |fetchwikidata=<list of fields to fetch values from Wikidata> |<local parameter>}}
{{#invoke:WikidataIB |getCoords |name=<fieldname> |suppressfields=<list of fields which will never display> |fetchwikidata=<list of fields to fetch values from Wikidata> |<local parameter>}}
{{#invoke:WikidataIB |getQualifierValue |<PropertyID> |pval=<ID of target value for the property> |qual=<qualifier ID for that target value> |name=<fieldname> |suppressfields=<list of fields which will never display> |fetchwikidata=<list of fields to fetch values from Wikidata> |onlysourced=<yes/no>}}

Function getValue[edit]

  • getValue can also take a named parameter |qid= which is the Wikidata ID for the article. This will not normally be used but is available for testing, although it makes the call expensive.
  • The property to be returned is passed in the first unnamed property.
  • The name of the field that this function is called from is passed in the named parameter |name=, which is first checked against a blacklist of fields that are never to be displayed, (i.e. the call must return nil in all circumstances). If the field is not on the blacklist, it is then checked against a whitelist. If the name of the field matches, the call will return any locally supplied value if it is supplied as the second unnamed parameter, or the Wikidata value otherwise.
  • The name is compulsory when the blacklist or whitelist is used, so the module returns nil if it is not supplied.
  • The blacklist is passed in the named parameter |suppressfields=
  • The whitelist is passed in the named parameter |fetchwikidata=

The getValue function will accept a boolean parameter onlysourced which will suppress return of Wikidata values that are unsourced or only sourced to Wikipedia. The absence of the parameter, an empty parameter (|onlysourced=) and the empty string ("") all default to true (i.e. only referenced values are returned). The values no, false and 0 are treated as false (i.e. all values are returned); any other value is true (although |onlysourced=yes is recommended for readability).

The getValue function will accept a boolean parameter noicon which will suppress the trailing "edit at Wikidata" icon for when the returned value is to be further processed by the infobox (e.g. a url). The absence of the parameter or an empty parameter (|noicon=) default to false (i.e. the icon is added). The empty string ("") and the values no, false and 0 are treated as false; any other value is true (although |noicon=true is recommended for readability).

In order to handle the requirement for dates in mdy, dmy or just year formats, getValue accepts a named parameter |df= that may take the values "dmy", "mdy", or "y" - default is "dmy".

As an article may require either of suffixes BC and BCE, getValue accepts a named parameter |bc= that may take the values "BC", or "BCE" - default is "BCE". Some test cases are shown at Module talk:WikidataIB #Calls to getValue for dates.

Formatting multiple returned values[edit]

  • |sorted=<yes|no> is a boolean passed to enable sorting of the values returned. No parameter, or an empty string, or "false", or "no", or "0" disables sorting. It's only a very dumb alphabetical sort and sorts linked values as "[[ ..."
  • |sep=<separator characters> allows the separator between multiple returned values to be defined. The default is ", " (comma plus normal space). If the separator has leading or trailing spaces, enclose it in double quotes (e.g. |sep=" - "). Any double quotes are stripped from the separator. The pipe character (|) must be escaped as {{!}}.
  • |list=<hlist|ubl> allows multiple returned values to be displayed as a horizontal list (|list=hlist), or a vertical unbulleted list (|list=ubl). These override the separator and do not display the 'pen icon' linked to "Edit at Wikidata"

Function getPreferredValue[edit]

The getPreferredValue function works exactly like getValue, taking the same parameters, but if any values for a property have the preferred rank set, it will only return those values.

Comparison example[edit]

Fetching the name(s) of the Lua error in Module:Wikibase at line 27: attempt to index field 'wikibase' (a nil value). (P170) from Lua error in Module:Wikibase at line 27: attempt to index field 'wikibase' (a nil value). (Q29016906):

  • {{#invoke:WikidataIB |getValue |P170 |fetchwikidata=ALL |qid=Q29016906 |onlysourced=no}}Lua error at line 171: attempt to index field 'wikibase' (a nil value).
  • {{#invoke:WikidataIB |getPreferredValue |P170 |fetchwikidata=ALL |qid=Q29016906 |onlysourced=no}}Lua error at line 171: attempt to index field 'wikibase' (a nil value).

Function getSourcedValue[edit]

  • getSourcedValue works exactly as getValue does, but only returns values that have a reference to something other than a Wikipedia. That's not a guarantee of a reliable source, but it helps separate the wheat from the chaff.

Example of getSourcedValue[edit]

From Lua error in Module:Wikibase at line 27: attempt to index field 'wikibase' (a nil value). (Q151973):

Burton currently has four values for Lua error in Module:Wikibase at line 27: attempt to index field 'wikibase' (a nil value). (P106) on Wikidata:

Using getValue in Richard Burton:

  • {{#invoke:WikidataIB |getValue |P106 |name=occupation |fetchwikidata=ALL}} -> Lua error at line 171: attempt to index field 'wikibase' (a nil value).

Using getSourcedValue in Richard Burton:

  • {{#invoke:WikidataIB |getSourcedValue |P106 |name=occupation |fetchwikidata=ALL}} -> Lua error at line 171: attempt to index field 'wikibase' (a nil value).

Function getCoords[edit]

  • getCoords can also take a named parameter |qid= which is the Wikidata ID for the article. This will not normally be used but is available for testing, although it makes the call expensive.
  • The coordinates from Wikidata are parsed and passed to Template:Coord which returns the display as if it were called manually.
  • The name of the field that this function is called from is passed in the named parameter |name=, which is first checked against a blacklist of fields that are never to be displayed, (i.e. the call must return nil in all circumstances). If the field is not on the blacklist, it is then checked against a whitelist. If the name of the field matches, the call will return any locally supplied value if it is supplied as the unnamed parameter, or the Wikidata value otherwise.
  • The name is compulsory when the blacklist or whitelist is used, so the module returns nil if it is not supplied.
  • The blacklist is passed in the named parameter |suppressfields=
  • The whitelist is passed in the named parameter |fetchwikidata=

Function getQualifierValue[edit]

The getQualifierValue is for use when we want to fetch the value of a qualifier. We need to know the property and the value of the property that it qualifies. The parameters are:

  • The property ID passed in the unnamed parameter (or |1=)
  • The target value for that property in |pval=
  • The qualifier ID for that target value in |qual=
  • The name of the field where its called from to implement whitelisting and blacklisting of the property in
  • The list of fields to be fetched ("whitelist") in |fetchwikidata= - accepts |fetchwikidata=ALL to fetch all fields
  • Optional list of fields not to be displayed ("blacklist") in |suppressfields=
  • Optional boolean to specify whether only sourced values of the property are returned (defaults to "no") in |onlysourced=
  • Optional item ID for arbitrary access (expensive call!) in |qid=

Example of getQualifierValue[edit]

In Lua error in Module:Wikibase at line 27: attempt to index field 'wikibase' (a nil value). (Q1513315) there is a property Lua error in Module:Wikibase at line 27: attempt to index field 'wikibase' (a nil value). (P793), which has a value Lua error in Module:Wikibase at line 27: attempt to index field 'wikibase' (a nil value). (Q385378). That has two qualifiers, Lua error in Module:Wikibase at line 27: attempt to index field 'wikibase' (a nil value). (P580) and Lua error in Module:Wikibase at line 27: attempt to index field 'wikibase' (a nil value). (P582). To get the start date:

  • {{#invoke:WikidataIB |getQualifierValue |P793 |pval=Q385378 |qual=P580 |name=xyz |fetchwikidata=ALL }}

In South Pole Telescope it returns:

  • Lua error at line 171: attempt to index field 'wikibase' (a nil value).

Function getLink[edit]

getLink returns the label for a Qid wiki-linked to the local article (if the article exists). If label doesn't exist, it returns the Qid wiki-linked to the local article (if the article exists).

Function getLabel[edit]

getLabel returns the label for a Qid. If label doesn't exist, it returns the Qid. Note that this is the label given to the Wikidata entry in the same language as the current Wikipedia, if the label exists.

  • {{#invoke:WikidataIB |getLabel |Q29016906}}Lua error at line 110: attempt to index field 'wikibase' (a nil value).
  • {{#invoke:WikidataIB |getLabel |Q3621491}}Lua error at line 110: attempt to index field 'wikibase' (a nil value).

Function getAT[edit]

getAT returns the article title for a Qid. If the article title doesn't exist, it returns nothing. Note that this is the title of the article in the current Wikipedia, if the interlanguage link exists in the Wikidata entry.

  • {{#invoke:WikidataIB |getAT |Q29016906}}Lua error at line 561: attempt to index field 'wikibase' (a nil value).
  • {{#invoke:WikidataIB |getAT |Q3621491}}Lua error at line 561: attempt to index field 'wikibase' (a nil value).

Function formatDate[edit]

formatDate accepts a datetime of the usual format from mw.wikibase.entity:formatPropertyValues, like "1 August 30 BCE" as parameter 1 and formats it according to the df (date format) and bc parameters.

  • {{#invoke:WikidataIB |formatDate | 1 August 30 BCE |bc=BCE |df=dmy}} → 1 August 30 BCE
  • {{#invoke:WikidataIB |formatDate | 1 August 30 BCE |bc=BC |df=mdy}} → August 1, 30 BC
  • df = "dmy" / "mdy" / "y" - default is "dmy"
  • bc = "BC" / "BCE" - default is "BCE"

Coding into an infobox[edit]

Typically, the getValue call will be invoked in an infobox definition, using appropriate template parameters. One simple implementation is given as an example in Template:Infobox book/Wikidata/Sandbox. As an illustration, the 'author' field in the infobox is coded like this:

| label2  = Author{{#if:{{{authors|}}}|s}}
|  data2  = {{#invoke:WikidataIB |getValue |P50 |name=author |fetchwikidata={{{fetchwikidata|}}} |suppressfields={{{suppressfields|}}} |{{{authors|{{{author|}}}}}} }}

The property to be fetched is the first unnamed parameter. In this case it is Lua error in Module:Wikibase at line 27: attempt to index field 'wikibase' (a nil value). (P50).

The name of the field is passed in |name= and that name is checked against the blacklist and the whitelist. To always suppress the author field in a particular article, an editor will set |suppressfields=author in the infobox. The author field will then never be displayed.

If the field is not blacklisted, then the infobox can be set to display a locally supplied value for author simply by setting |author=George Orwell, for example, in the infobox. It also accepts |authors=. If the name of the field is on the whitelist, e.g. |fetchwikidata=author; genre; pub_date; pages; dewey; congress, and the local value is not supplied, then the infobox will display the value retrieved from Wikidata. Any separators can be used, except | and {}.

As a shorthand, |fetchwikidata=ALL will fetch all of the fields that are not blacklisted, as long as no local value is already provided in the article for a given field.

Since Wikidata labels are normally lower case, the sentence case function from Module:String2 can be used to capitalise the first letter of the returned text, e.g.

Coodinates[edit]

The getCoords call will display the output of Template:Coord when supplied with the coordinates returned from Wikidata.There's an example in Template:Sandbox/Infobox biosphere reserve where it's coded like this:

|label20 = Coordinates
| data20 = {{#invoke:WikidataIB |getCoords |name=coordinates |suppressfields={{{suppressfields|}}} |fetchwikidata={{{fetchwikidata|}}} |{{{coordinates|}}} }}

Upgrading existing infoboxes[edit]

Since the parameter |fetchwikidata= is needed for any Wikidata functionality, an existing infobox may be replaced by an infobox incorporating these calls without any change whatsoever to any article. Each article using the new infobox can later be enabled by supplying |fetchwikidata=ALL, or a list of required fields for that article. At that point, the onus is on the editor enabling the functionality to check that no unwanted fields are now being displayed. If so, they can be added to a blacklist for the article by setting |suppressfields= to the list of unwanted fields.

Verifiability[edit]

Where it will always be essential for a particular field to only contain values that are referenced, use getValue, making sure that |onlysourced= is not set to 'false', '0' or 'no'. By default it will exclude values that are unsourced or only sourced to a Wikipedia, thus making the job of checking easier at the article level. If unsourced data is acceptable (!), set |onlysourced=true. As it is beyond my wit to produce an automated mechanism that knows whether an existing source is reliable or not in a given context, that job must still be performed at the article level by an editor familiar with the subject. It should always be done when first enabling Wikidata for that article.

Examples[edit]

This section is taken from Template:Infobox book/Wikidata/Sandbox/doc.

No Wikidata[edit]

{{Infobox book/Wikidata/Sandbox
| suppressfields =
| fetchwikidata  =
| name           = Animal Farm
| title_orig     = Animal Farm: A Fairy Story
| image          = Animal Farm - 1st edition.jpg
| image_size     = 200px
| caption        = First edition cover
| author         = [[George Orwell]]
| country        = United Kingdom
| language       = English
| genre          = Political satire
}}

Works as a non-aware infobox: only locally supplied parameters are displayed.

{{Infobox book/Wikidata/Sandbox
| name           = Animal Farm
| title_orig     = Animal Farm: A Fairy Story
| image          = Animal Farm - 1st edition.jpg
| image_size     = 200px
| caption        = First edition cover
| author         = [[George Orwell]]
| country        = United Kingdom
| language       = English
| genre          = Political satire
}}

The blacklist and whitelist can be omitted if unused

All Wikidata[edit]

{{Infobox book/Wikidata/Sandbox
| suppressfields = 
| fetchwikidata  = author; genre; pub_date; pages; dewey; congress
}}

Fetches all of its values from Wikidata.

{{Infobox book/Wikidata/Sandbox
| fetchwikidata  = ALL
}}

As shorthand, the |fetchwikidata= can be set to ALL to fetch all available fields. Any of them can be suppressed by |suppressfields=, or overridden by supplying a local value.

Never display genre[edit]

{{Infobox book/Wikidata/Sandbox
| suppressfields = genre
| fetchwikidata  = author; genre; pub_date; pages; dewey; congress
}}

The genre field will always be suppressed, even if a local value is supplied.

{{Infobox book/Wikidata/Sandbox
| suppressfields = genre
| fetchwikidata  = author; genre; pub_date; pages; dewey; congress
| genre          = Political satire
}}

Local override[edit]

{{Infobox book/Wikidata/Sandbox
| fetchwikidata  = author; genre; pub_date; pages; dewey; congress
| genre          = Political satire
}}

The genre field is set to display "Political satire", no matter what is stored in Wikidata.

{{Infobox book/Wikidata/Sandbox
| fetchwikidata  = ALL
| genre          = Novel
}}

The genre field is set to display "Novel", no matter what is stored in Wikidata.

Don't fetch genre[edit]

{{Infobox book/Wikidata/Sandbox
| suppressfields = 
| fetchwikidata  = author; pub_date; pages; dewey; congress
}}

The genre field will not be fetched from Wikidata.

Coordinates[edit]

{{Sandbox/Infobox biosphere reserve
| fetchwikidata = ALL
}}

Displays coordinates when used in an article where Wikidata has coordinates.

See also[edit]


-- Module to try out use of a blacklist and whitelist for infobox fields
-- can take a named parameter |qid which is the Wikidata ID for the article. This will not normally be used
-- Fields in blacklist are never to be displayed, i.e. module must return nil in all circumstances
-- Fields in whitelist return local value if it exists or the Wikidata value otherwise
-- The name of the field that this function is called from is passed in named parameter |name
-- The name is compulsory when blacklist or whitelist is used, so the module returns nil if it is not supplied
-- blacklist is passed in named parameter |suppressfields
-- whitelist is passed in named parameter |fetchwikidata

local p = {}

local i18n =
{
    ["errors"] =
    {
        ["property-not-found"] = "Property not found.",
        ["entity-not-found"] = "Wikidata entity not found.",
        ["unknown-claim-type"] = "Unknown claim type.",
        ["unknown-entity-type"] = "Unknown entity type.",
        ["qualifier-not-found"] = "Qualifier not found.",
        ["site-not-found"] = "Wikimedia project not found.",
		["unknown-datetime-format"] = "Unknown datetime format.",
		["local-article-not-found"] = "Article is available on Wikidata, but not on Wikipedia"
    },
    ["months"] =
    {
    	"January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December"
    }
}

-------------------------------------------------------------------------------
-- Private functions
-------------------------------------------------------------------------------

-------------------------------------------------------------------------------
-- formatDate takes a datetime of the usual format from mw.wikibase.entity:formatPropertyValues
-- like "1 August 30 BCE" as parameter 1 and formats it according to the df (date format) and bc parameters
-- df = ["dmy" / "mdy" / "y"] default will be "dmy"
-- bc = ["BC" / "BCE"] default will be "BCE"
-- first the local version
local format_Date = function(datetime, dateformat, bc)
	local datetime = datetime or "1 August 30 BCE" -- in case of nil value
	-- chop off multiple vales and/or any hours, mins, etc.
	-- keep anything before punctuation - we just want a single date:
	local dateval = string.match( datetime, "[%w ]+")
	
	local dateformat = string.lower(dateformat or "dmy") -- default to dmy
	
	local bc = string.upper(bc or "") -- can't use nil for bc
	-- we only want to accept two possibilities: BC or default to BCE
	if bc=="BC" then
		bc = "&nbsp;BC" -- prepend the space. **internationalise later**
	else
		bc = "&nbsp;BCE"
	end
	
	local postchrist = true -- start by assuming no BCE
	local dateparts = {}
	for word in string.gmatch(dateval, "%w+") do
		if word == "BCE" or word == "BC" then -- **internationalise later**
			postchrist = false
		else
			-- we'll keep the parts that are not 'BCE' in a table
			dateparts[#dateparts + 1] =  word
		end
	end
	if postchrist then bc = "" end -- set AD dates to no suffix **internationalise later**
	
	local sep = "&nbsp;" -- separator is nbsp
	local fdate = table.concat(dateparts, "&nbsp;") -- formatted date defaults to same order as input
	
	-- if we have day month year, check dateformat
	if #dateparts == 3 then
		if dateformat == "y" then
			fdate = dateparts[3]
		elseif dateformat == "mdy" then
			fdate = dateparts[2] .. sep .. dateparts[1] .. "," .. sep .. dateparts[3]
		end
	elseif #dateparts == 2 and dateformat == "y" then
		fdate = dateparts[2]
	end
	
	return fdate .. bc
end

-------------------------------------------------------------------------------
-- parseParam takes a (string) parameter, e.g. from the list of frame arguments,
-- and makes "false", "no", and "0" into the (boolean) false
-- it makes the empty string and nil into the (boolean) value passed as default
-- allowing the parameter to be true or false by default.
local parseParam = function(param, default)
	if param and (#param > 0) then
		param = param:lower()
		if (param == "false") or (param == "no") or (param == "0") then
			return false
		else
			return true
		end
	else
		return default
	end
end

-------------------------------------------------------------------------------
-- The label in a Wikidata item is subject to vulnerabilities 
-- that an attacker might try to exploit.
-- It needs to be 'sanitised' by removing any wikitext before use.
-- If it doesn't exist, just return the id for the item
local labelOrId = function (id)
	local label = mw.wikibase.label(id)
	if label then
		return mw.text.nowiki(label)
	else
		return id
	end
end

-------------------------------------------------------------------------------
-- sourced takes a table representing a statement that may or may not have references
-- it counts how many references are sourced to something not contianing the word "wikipedia"
-- the reference string "ref" is available for debugging
-- it returns a boolean = true if there are any sourced references.
local sourced = function(claim)
	local refs = 0
	if claim.references then
		for kr, vr in pairs(claim.references) do
			local ref = mw.wikibase.renderSnaks(vr.snaks)
			if not ref:find("Wikipedia") then refs = refs + 1 end
		end
	end
	return refs > 0
end

-- parseInput processes the Q-id , the blacklist and the whitelist
-- if an input parameter is supplied, it returns that and ends the call.
-- it returns a boolean indicating whether or not the call should continue
-- and an object containing all of the Wikidata for the Qid supplied or the current page
local parseInput = function(frame, input_parm, property_id)
	-- can take a named parameter |qid which is the Wikidata ID for the article.
	-- This will not normally be used because it's an expensive call.
	local qid = frame.args.qid
	if qid and (#qid == 0) then qid = nil end
	
	-- The blacklist is passed in named parameter |suppressfields
	local blacklist = frame.args.suppressfields
	
	-- The whitelist is passed in named parameter |fetchwikidata
	local whitelist = frame.args.fetchwikidata
	
	-- The name of the field that this function is called from is passed in named parameter |name
	local fieldname = frame.args.name
	if blacklist then
		-- The name is compulsory when blacklist is used, so return nil if it is not supplied
		if not fieldname or (#fieldname == 0) then return false, nil, nil end
		-- If this field is on the blacklist, then return nil
		if blacklist:find(fieldname) then return false, nil, nil end
	end
	
	-- If we got this far then we're not on the blacklist
	-- The blacklist overrides any locally supplied parameter as well
	-- If a non-blank input parameter was supplied return it
	if input_parm then return false, input_parm, nil end
	
	-- Otherwise see if this field is on the whitelist:
	if not (whitelist and (whitelist == 'ALL' or whitelist:find(fieldname))) then
		-- not on the whitelist so just return what should be a nil input parameter
		return false, input_parm, nil
	end
	
	-- See what's on Wikidata:
	local entity = mw.wikibase.getEntityObject(qid)
	if entity and entity.claims then
		local props = entity.claims[property_id]
		if props and props[1] then 
			return true, entity, props
		end
	end
	-- no property on Wikidata
	return false, input_parm, nil
end

local function _getvalue(frame, entity, props, filter, propertyID) 
	-- onlysourced is a boolean passed to return only values sourced to other than Wikipedia
	-- if nothing or an empty string is passed set it true
	-- if "false" or "no" or "0" is passed set it false
	local onlysrc = parseParam(frame.args.onlysourced, true)
	
	-- noicon is a boolean passed to suppress the trailing "edit at Wikidata" icon
	-- for use when the value is processed further by the infobox
	-- if nothing or an empty string is passed set it false
	-- if "false" or "no" or "0" is passed set it false
	local noic = parseParam(frame.args.noicon, false)
	
	-- wdlinks is a boolean passed to enable links to Wikidata when no article exists
	-- if nothing or an empty string is passed set it false
	-- if "false" or "no" or "0" is passed set it false
	local wdl = parseParam(frame.args.wdlinks, false)
	
	-- sorted is a boolean passed to enable sorting of the values returned
	-- if nothing or an empty string is passed set it false
	-- if "false" or "no" or "0" is passed set it false
	local sorted = parseParam(frame.args.sorted, false)
	
	-- separator is a string that is used to separate multiple returned values
	-- if nothing or an empty string is passed set it to the default
	-- any double-quotes " are stripped out, so that spaces may be passed
	-- e.g. |sep=" - "
	local sepdefault = ", " -- **internationalise later**
	local separator = frame.args.sep or ""
	separator = string.gsub(separator, '"', '')
	if #separator == 0 then
		separator = sepdefault
	end
	
	-- list is a string that may be "", "hlist" or "ubl"
	-- this controls whether multiple values are output as comma-separated
	-- as a horizontal list (hlist) or unbulleted list (ubl)
	local list = frame.args.list or ""
	if list~="hlist" and list~="ubl" then list = "" end
	
	-- So now we have something to return: deal with (1) a Wikibase-entity; (3) a date; (3) anything else
	local lang = mw.language.getContentLanguage().code
	local thisQid = entity.id
	-- table 'out' is going to to store the return value(s):
	local out = {}
	local icon = " [[File:Blue pencil.svg |frameless |text-top |10px |alt=Edit this on Wikidata |link=https://www.wikidata.org/wiki/" .. thisQid .. "?uselang=" .. lang .. "#" .. propertyID .. "|Edit this on Wikidata]]"
	if props[1].mainsnak.datatype == "wikibase-item" then
		-- it's wiki-linked value, so output as link if possible
		for k, v in pairs(props) do
			if filter(v) and ((onlysrc == false) or sourced(v)) then -- has valid refs or all values required
				if v.mainsnak.snaktype == "somevalue" then -- check for value is unknown
					out[#out + 1] = "Unknown"
				else
					local qnumber = "Q" .. v.mainsnak.datavalue.value["numeric-id"]
					local sitelink = mw.wikibase.sitelink(qnumber)
					local label = labelOrId(qnumber)
					if sitelink then
						out[#out + 1] = "[[" .. sitelink .. "|" .. label .. "]]"
					else
						-- no sitelink, so check first for a redirect with that label
						local artitle = mw.title.new(label, 0)
						if artitle.id > 0 then
							if artitle.isRedirect then
								-- no sitelink, but there's a redirect with the same title as the label
								-- let's link to that
								out[#out + 1] = "[[" .. label .. "|" .. label .. "]]"
							else
								-- no sitelink and not a redirect but an article exists with the same title as the label
								-- that's probably a dab page, so output the plain label
								out[#out + 1] = label
							end
						else
							-- no article or redirect with the same title as the label
							if wdl then
								-- show that there's a Wikidata entry available
								out[#out + 1] = "[[:d:Q" .. v.mainsnak.datavalue.value["numeric-id"] .. "|" .. label .. "]]&nbsp;<span title='" .. i18n["errors"]["local-article-not-found"] .. "'>[[File:Wikidata-logo.svg|16px|alt=|link=]]</span>"
							else
								-- no wikidata links required, so just give the plain label
								out[#out + 1] = label
							end
						end
					end
				end
			end
		end
	elseif props[1].mainsnak.datatype == "time" then
		-- it's a date value, so output according to formatting preferences
		for k, v in pairs(props) do
			-- check for references, and count valid references
			if filter(v) and ((onlysrc == false) or sourced(v)) then
				if v.mainsnak.snaktype == "somevalue" then -- check for value is unknown
					out[#out + 1] = "Unknown"
				else
					local timestamp = v.mainsnak.datavalue.value.time
					-- A year can be stored like this: "+1872-00-00T00:00:00Z",
					-- which is processed here as if it were the day before "+1872-01-01T00:00:00Z",
					-- and that's the last day of 1871, so the year is wrong.
					-- So fix the month 0, day 0 timestamp to become 1 January instead:
					timestamp = timestamp:gsub("%-00%-00T", "-01-01T")
					local dateprecision = v.mainsnak.datavalue.value.precision
					local dateformat = "y"
					local fpvdate = tonumber(timestamp:sub(2, 5))
					if timestamp:sub(1, 1) == "-" then
						fpvdate = fpvdate .. " BCE"
					end
					if dateprecision > 9 then -- add month
						fpvdate = i18n.months[tonumber(timestamp:sub(7, 8))] .. " " .. fpvdate
						dateformat = frame.args.df
					end
					if dateprecision > 10 then -- add day
							fpvdate = tonumber(timestamp:sub(10, 11)) .. " " .. fpvdate
					end
					out[#out+1] = format_Date(fpvdate, dateformat, frame.args.bc)
				end -- check for unknown value
			end -- check for sourced
		end -- loop through k-v pairs
	else
		-- not a linkable article title or a date
		-- this needs to be expanded to cater for multiple values
		local reflist = ""
		local refs = 0
		for k, v in pairs(props) do
			-- check for references,
			-- construct a reference list for debugging
			-- and count valid references
			if v.references then
				for kr, vr in pairs(v.references) do
					local ref = mw.wikibase.renderSnaks(vr.snaks)
					reflist = reflist .. " <span style='color:#0DD;'>" .. ref .. "</span>"
					if not ref:find("Wikipedia") then refs = refs + 1 end
				end
			end
		end
		local propertyValue = entity:formatPropertyValues(propertyID).value
		if (refs > 0) or (onlysrc == false) then -- has valid refs or all values required
			out[#out+1] = propertyValue
		end
	end
	
	-- if there's anything to return, then return a list
	-- comma-separated by default, but may be specified by the sep parameter
	-- optionally specify a hlist or 
	if #out > 0 then
		if sorted then table.sort(out) end
		if list == "hlist" then
			return frame:expandTemplate{title = 'Hlist', args = out}
		elseif list == "ubl" then
			return frame:expandTemplate{title = 'Unbulleted list', args = out}
		else
			if noic then
				return table.concat(out, separator)
			else
				return table.concat(out, separator) .. icon
			end
		end
	else
		return nil -- no items had valid reference
	end
end
-------------------------------------------------------------------------------
-- Public functions
-------------------------------------------------------------------------------
-- getValue is used to get a value, or a comma separated list of them if multiple values exist
--

p.getValue = function(frame)
	local propertyID = mw.text.trim(frame.args[1] or "")
	
	-- There may be a local parameter supplied, if it's blank, set it to nil
	local input_parm =  mw.text.trim(frame.args[2] or "")
	if input_parm and (#input_parm == 0) then input_parm = nil end
	local success, errorOrEntity, props = parseInput(frame, input_parm, propertyID)
	if not success then
		return errorOrEntity
	else
		entity = errorOrEntity
	end
	local function filter(claim)
		return true
	end
	return _getvalue(frame, entity, props, filter, propertyID)
end
-------------------------------------------------------------------------------
-- getPreferredValue is used to get a value, or a comma separated list of them if multiple values exist
-- If preferred ranks are set, it will return those values, otherwise values with normal ranks
--
p.getPreferredValue = function(frame)
	local propertyID = mw.text.trim(frame.args[1] or "")
	
	-- There may be a local parameter supplied, if it's blank, set it to nil
	local input_parm =  mw.text.trim(frame.args[2] or "")
	if input_parm and (#input_parm == 0) then input_parm = nil end
	local success, errorOrEntity, props = parseInput(frame, input_parm, propertyID)
	if not success then
		return errorOrEntity
	else
		entity = errorOrEntity
	end
	local prefflag = false
	for k, v in pairs(props) do
		if v.rank == "preferred" then 
			prefflag = true 
			break
		end
	end
	local function filter(claim)
		return claim.rank == "preferred" or prefflag == false
	end
	return _getvalue(frame, entity, props, filter, propertyID)
end

-------------------------------------------------------------------------------
-- getSourcedValue is used to get a value, or a comma separated list of them if multiple values exist
-- but only values that are sourced are returned
-- redundant to getValue with onlysourced=true but kept for backwards compatibility
-- now defined via getValue
--
p.getSourcedValue = function(frame)
	frame.args.onlysourced = "yes"
	return p.getValue(frame)
end


-------------------------------------------------------------------------------
-- getCoords is used to get coordinates for display in an infobox
-- whitelist and blacklist are implemented
-- optional 'display' parameter is allowed, defaults to "inline, title"
--
p.getCoords = function(frame)
	local propertyID = "P625"
	local input_parm =  mw.text.trim(frame.args[1] or "")
	if input_parm and (#input_parm == 0) then input_parm = nil end
	
	-- if there is a 'display' parameter supplied, use it
	-- otherwise default to "inline, title"
	local disp = frame.args.display
	if (not disp) or (#disp == 0) then
		disp = "inline, title"
	end
	
	local success, errorOrEntity = parseInput(frame, input_parm, property_id)
	if not success then
		return errorOrEntity
	else
		local entity = errorOrEntity
		local lat_long = {}
		local coords = entity:formatPropertyValues(propertyID).value
		-- the latitude and longitude are returned like this: nn°nn&#39;nn.n&#34;
		-- using html entities with hex values really screws up parsing the numbers - thanks devs
		local lat = mw.ustring.match(coords, "^[^,]*")  -- everything from the start to before the comma
		local long = mw.ustring.match(coords, "[^ ]*$") -- everything from after the space to the end
		lat = lat:gsub("&#%d%d;", ":")                  -- clean out the html entities
		long = long:gsub("&#%d%d;", ":")                -- clean out the html entities
		-- read the latitude numbers into a table
		for num in mw.ustring.gmatch(lat, "%d+%.?%d*") do
  			lat_long[#lat_long + 1] = num
		end
		-- add the N/S
		lat_long[#lat_long + 1] = lat:sub(-1)
		-- read the longitude numbers into a table
		for num in mw.ustring.gmatch(long, "%d+%.?%d*") do
			lat_long[#lat_long + 1] = num
		end
		-- add E/W for long
		lat_long[#lat_long + 1] = long:sub(-1)
		-- add named parameter for display
		lat_long["display"] = disp
		-- invoke template Coord with the values stored in the table
		return frame:expandTemplate{title = 'coord', args = lat_long}
	end
end


-------------------------------------------------------------------------------
-- getQualifierValue is used to get a formatted value of a qualifier
-- 
-- The call needs:	a property (the unnamed parameter or 1=)
-- 					a target value for that property (pval=)
--					a qualifier for that target value (qual=)
-- The usual whitelisting and blacklisting of the property is implemented
-- The boolean onlysourced= parameter can be set to return nothing
-- when the property is unsourced (or only sourced to Wikipedia)
-- 
p.getQualifierValue = function(frame)
	local propertyID = mw.text.trim(frame.args[1] or "")

	-- The PropertyID of the target value of the property
	-- whose qualifier is to be returned is passed in named parameter |pval=
	local propvalue = frame.args.pval
	
	-- The PropertyID of the qualifier
	-- whose value is to be returned is passed in named parameter |qual=
	local qualifierID = frame.args.qual

	-- onlysourced is a boolean passed to return qualifiers
	-- only when property values are sourced to something other than Wikipedia
	-- if nothing or an empty string is passed set it false
	-- if "false" or "no" or 0 is passed set it false
	local onlysrc = parseParam(frame.args.onlysourced,false)
	
	local success, errorOrEntity, props = parseInput(frame,nil, propertyID)
	if not success then
		return errorOrEntity
	else
		local entity = errorOrEntity
		-- Scan through the values of the property
		-- we want something like property is P793, significant event (in propertyID)
		-- whose value is something like Q385378, construction (in propvalue)
		-- then we can return the value(s) of a qualifier such as P580, start time (in qualifierID)
		for k1, v1 in pairs(props) do
			if v1.mainsnak.snaktype == "value" and v1.mainsnak.datavalue.type == "wikibase-entityid" then
				-- It's a wiki-linked value, so check if it's the target (in propvalue)
				-- and if it has qualifiers
				if v1.mainsnak.datavalue.value.id == propvalue and v1.qualifiers then
					if (onlysrc == true) and not sourced(v1) then
						return
					end
					-- if we've got this far, we have a (sourced) claim with qualifiers
					-- which matches the target, so find the value(s) of the qualifier we want
					local quals = v1.qualifiers[qualifierID]
					local out = {}
					if quals then
						if quals[1].datatype == "wikibase-item" then
							for k2, v2 in pairs(quals) do
								local valueID = v2.datavalue.value.id
								local sitelink = mw.wikibase.sitelink(valueID)
								local label = labelOrId(valueID)
								if sitelink then
									out[#out + 1] = "[[" .. sitelink .. "|" .. label .. "]]"
								else
									out[#out + 1] = "[[:d:" .. valueID .. "|" .. label .. "]]&nbsp;<span title='" .. i18n["errors"]["local-article-not-found"] .. "'>[[File:Wikidata-logo.svg|16px|alt=|link=]]</span>"
								end
							end
							return table.concat(out, ", ")
						else
							return mw.wikibase.renderSnaks(quals)
						end
					end
				end
			end -- of loop through values of propertyID
		end
	end
	return nil
end

-------------------------------------------------------------------------------
-- getLink returns the label for a Qid wiki-linked to the local article (if the article exists)
-- if label doesn't exist, it returns the Qid wiki-linked to the local article (if the article exists)
--
p.getLink = function(frame)
	local itemID = mw.text.trim(frame.args[1] or "")
	if itemID == "" then return end
	local sitelink = mw.wikibase.sitelink(itemID)
	local label = labelOrId(itemID)
	if sitelink then
		return "[[" .. sitelink .. "|" .. label .. "]]"
	else
		return label
	end
end


-------------------------------------------------------------------------------
-- getLabel returns the label for a Qid
-- if label doesn't exist, it returns the Qid
--
p.getLabel = function(frame)
	local itemID = mw.text.trim(frame.args[1] or "")
	if itemID == "" then return end
	return labelOrId(itemID)
end


-------------------------------------------------------------------------------
-- getAT returns the article title for a Qid
-- or nothing if it doesn't exist
--
p.getAT = function(frame)
	local itemID = mw.text.trim(frame.args[1] or "")
	if itemID == "" then return end
	return mw.wikibase.sitelink(itemID)
end


-------------------------------------------------------------------------------
-- formatDate is a wrapper to export the private function format_Date
--
p.formatDate = function(frame)
	return format_Date(frame.args[1], frame.args.df, frame.args.bc)
end

-------------------------------------------------------------------------------
-- checkBlacklist allows a test to check whether a named field is suppressed
-- {{#if:{{#invoke:WikidataIB |checkBlacklist |name=Joe |suppressfields=Dave; Joe; Fred}} | not blacklisted | blacklisted}}
-- displays "blacklisted"
-- {{#if:{{#invoke:WikidataIB |checkBlacklist |name=Jim |suppressfields=Dave; Joe; Fred}} | not blacklisted | blacklisted}}
-- displays "not blacklisted"
--
p.checkBlacklist = function(frame)
	local blacklist = frame.args.suppressfields
	local fieldname = frame.args.name
	if blacklist and fieldname then
		if blacklist:find(fieldname) then return nil end
		return true
	end
end


return p