Extension:TemplateData

**MediaWiki extensions manual**
TemplateData; Release status: stable
Implementation	Tag, API
Description	Allows to store, retrieve and visualise information about templates
Author(s)	Timo Tijhof, Moriel Schottlender, James Forrester, Trevor Parscal, Bartosz Dziewoński, Marielle Volz, ...
Latest version	0.1.2 (Continuous updates)
Compatibility policy	Snapshots releases along with MediaWiki. Master is not backward compatible.
PHP	5.4+
Database changes	No
License	GNU General Public License 2.0 or later
Download	Download extension ; Git [?]: Download Git master; browse repository (Phabricator · GitHub); commit history; repository contributors (GitHub); code review;
Help	Help:Extension:TemplateData
	Parameters $wgTemplateDataEditorNamespaces; $wgTemplateDataUseGUI;
	Tags ‎<templatedata>
	Hooks used EditPage::showEditForm:fields; EditPage::showEditForm:initial; MultiContentSave; OutputPageBeforeHTML; ParserFetchTemplateData; ParserFirstCallInit; ResourceLoaderRegisterModules;
Quarterly downloads	285 (Ranked 15th)
Public wikis using	6,971 (Ranked 24th)
	Translate the TemplateData extension if it is available at translatewiki.net
Issues	Open tasks · Report a bug

Translate this page

This extension comes with MediaWiki 1.35 and above. Thus you do not have to download it again. However, you still need to follow the other instructions provided.

The TemplateData extension introduces a ‎<templatedata> tag and an API which together allow editors to specify how templates and their parameters should be used. This information is available as a nicely-formatted table for end-users, and as a JSON API, which enables other systems (e.g. VisualEditor ) to build interfaces for working with templates. See Help:TemplateData for in-depth help.

Installation

Download and move the extracted TemplateData folder to your extensions/ directory.
Developers and code contributors should install the extension from Git instead, using:cd extensions/ git clone https://gerrit.wikimedia.org/r/mediawiki/extensions/TemplateData
Add the following code at the bottom of your LocalSettings.php file:
```
wfLoadExtension( 'TemplateData' );
```
Done – Navigate to Special:Version on your wiki to verify that the extension is successfully installed.

Editing data

The TemplateData extension works through having a ‎<templatedata> tag defined in the wikitext of a template page (optionally it can be transcluded from a different page as well). This is designed to be compatible with the common layout many wikis have of transcluding template documentation from a separate page (but is not required). This content of the ‎<templatedata> tag must be valid JSON using the format described below; note that all descriptions must be in plain text (no wikitext is accepted inside the template data).

When a ‎<templatedata> block is included on a page, the TemplateData extension performs the following checks when the page is being saved:

The contents must be valid JSON;
Each item within the JSON structure must be of the expected type as specified below (e.g. object, array, or a primitive); and
For those items which have a specified list of possible values (e.g. the type of a parameter), the value in the JSON object must match one of those values.

If any of these checks fails, the server will not be permitted saving and an error message will be displayed above the edit page.

For autovalue items, T4700 prevents subst: from working in any template that is added inside a tag, including ‎<ref> and ‎<gallery> tags. The TemplateData block will save correctly, but the resulting wikitext will not be parsed correctly when the template is used.

Please avoid using {{#tag:templatedata}} as it makes it impossible to use the template data editor.

Format

The below is a visualised version of the JSON data as defined on the template page enclosed by ‎<templatedata>‎</templatedata> tags. The formal specification is available in the TemplateData repository. Refer to Specification.md for the latest version.

TemplateData object

The TemplateData object is a JSON root element enclosed in a ‎<templatedata> element on the template page.

Key	Type	Description
`description`	InterfaceText or `null`	A brief description of the template. It must be in plain text. Once filled, it can be displayed as caption when editing a single template and perhaps in search results when users pick one of many. The default is `null`. → For more details see: description
`params`	Object containing Param objects	An object that maps each parameter name of the template to a corresponding Param object describing the properties of that parameter. → For more details see: params
`paramOrder`	Array containing parameter name strings	The logical order in which parameters should be displayed. The array contains each parameter key exactly once. Each string must be a valid key in the `params` object. → For more details see: paramOrder
`sets`	Array containing Set objects	An array containing set specifications. A set is a group of parameters that should be used together. The default is []. Note that the `sets` functionality is still in development.
`format`	string, either `inline` or `block`	How the template's wikitext representation SHOULD be laid out. The default is `inline`. See #Custom_formats for other custom formats.
`maps`	Object containing Map objects	An object that links a simplified name of a third party consumer of the template data (i.e. Citoid, Special:MyLanguage/Wikidata, etc.) to a map object that in turn links a name of a consumer parameter to one or more corresponding names of template parameters.

Param object

Key Type Default Description

label

InterfaceText

null

A (very) brief name for the parameter. Try to keep under 20-ish characters.

→ For more details see: label

description

InterfaceText

null

A brief description of the parameter, for users to know which to pick from an option list.

→ For more details see: description

required

boolean

false

Whether the parameter is required for the template to work (true if this parameter must be specified).

→ For more details see: required

suggested

boolean

false

Whether the parameter is suggested for the template to be useful (true if this parameter should be specified).

→ For more details see: suggested

deprecated

boolean or string

false

Whether the parameter is deprecated. The value can be a string of instructions giving the user guidance what instead can be done, or be simply true.

→ For more details see: deprecated

aliases

Array containing strings

[]

List of aliases. An alias is an alternative name for the parameter that may be used instead of (not in addition to) the primary name. Aliases are not documented in a separate Parameter object. If they need more information, they should be in their own property marked "deprecated".

→ For more details see: aliases

default

InterfaceText

null

A fixed default value used by the template if no value is assigned to the parameter, or a description thereof.

→ For more details see: default

autovalue

string

null

A dynamically-generated default value in wikitext, such as today's date or the editing user's name; this will often involve wikitext substitution, such as {{subst:CURRENTYEAR}}.

→ For more details see: autovalue

example

InterfaceText

null

An example text for the parameter, to help users fill in the proper value.

→ For more details see: example

type

string

"unknown"

The type of the parameter, for (soft) type hinting. One of:

String Value	Type of Parameter
"unknown"	Assumed type if not set → For more details see: value ‘unknown’
"number"	Any numerical value (without decimal points or thousand separators) → For more details see: value ‘number’
"string"	Any textual value. May contain line breaks. → For more details see: value ‘string’
"line"	Short text field – use for names, labels, and other short-form fields. This is supposed to be text that is not expected to contain line breaks. → For more details see: value ‘line’
"boolean"	A boolean value ('1' for true, '0' for false, '' for unknown), see three-valued logic. → For more details see: value ‘boolean’
"date"	A date in ISO 8601 format, e.g. "2014-05-09" or "2014-05-09T16:01:12Z" → For more details see: value ‘date’
"url"	A URL, including protocol, e.g. "http://www.example.org", "https://example.org", or "//example.org". → For more details see: value ‘url’
"wiki-page-name"	A valid MediaWiki page name for the current wiki. Doesn't have to exist, but if not, should be a valid page name which could be created. → For more details see: value ‘wiki-page-name’
"wiki-file-name"	A valid MediaWiki file name for the current wiki. Doesn't have to exist, but if not, should be a valid file name which could be uploaded. Should not include the namespace (e.g. "Foo.svg" not "File:Foo.svg" or "Bild:Foo.svg"). → For more details see: value ‘wiki-file-name’
"wiki-template-name"	A valid MediaWiki Template name for the current wiki. → For more details see: value ‘wiki-template-name’
"wiki-user-name"	A valid MediaWiki user name for the current wiki. Doesn't have to exist, but if not, should be a valid user name which could be created. Should not include the namespace (e.g. "Foo" not "User:Foo" or "Usario:Foo"). → For more details see: value ‘wiki-user-name’
"content"	Page content in wikitext, such as text style, links, images, etc. → For more details see: value ‘content’
"unbalanced-wikitext"	Raw wikitext that should not be treated as standalone content because it is unbalanced – for example, templates concatenating incomplete wikitext as a bigger whole, such as `{{echo\|before=<u>\|after=</u>}}` → For more details see: value ‘unbalanced-wikitext’

→ For more details see: type

inherits

string

none
substituted

The name key of another parameter (must be a valid key in the params object). The current Parameter Object will inherit properties from the specified Parameter Object, with local properties overriding the inherited ones.

→ For more details see: inherits

suggestedvalues

Array containing strings

[]

An optional parameter property. Creates a list of parameter values to help users select the desired value. For the suggested values to be displayed as a combo box in VisualEditor, the parameter’s type must be set to one of the following: content, line, string, number, unknown or unbalanced wikitext.

→ For more details see: suggestedvalues

Set object

Key	Object or primitive type	Description
`label`	InterfaceText	A (very) brief name for the parameter set. Try to keep under 20-ish characters.
`params`	Array of strings	One or more names of parameters to include in the set (each must be a valid key in the `params` object). A parameter may be in multiple sets. Not every parameter must be in a set.

Maps structure

Maps is a single data structure that goes multiple levels deep. It became common to call the second level a “map object”.

Key	Type	Default	Description
name of consumer	object	{}	An object that links a name of a consumer to a map object that in turn links a name of a consumer parameter to one or more corresponding names of template parameters. The names of the template parameters can be specified either as a string (one name), an array of strings (several names), or an array of arrays of strings (several sets of names); each of these strings must be a valid key in the `params` object elsewhere in the same template's TemplateData. A specific template parameter may be in multiple maps, and it may be used in the values of multiple keys in a given map, but not every template parameter must be in a map. A shortened example from English Wikipedia's Template:Cite_news#TemplateData illustrates the structure of map objects. { "proveit": { "main": "title", "textarea": [ "quote" ] }, "citoid": { "title": "title", "url": "url", "publisher": "publisher", "publicationTitle": "work", "date": "date", "ISSN": [ "issn" ], "ISBN": [ "isbn" ], "contributor": "others", "author": [ [ "first", "last" ], [ "first2", "last2" ], [ "first9", "last9" ] ], "editor": [ [ "editor-first", "editor-last" ] ] } }

InterfaceText (string or object)

A free-form plain-text string (i.e. no wikitext or HTML) in the content-language of the wiki, or an object containing those strings keyed by language code.

The default value for all InterfaceText fields is null.

String type

If it is a string, it must contain a non-localized string in the content language of the local wiki.

Object type

If it is an object, the object must have this mapping:

Key	Type	Description
Wikipedia language code	string	Localized string for users of that interface language.

Example of object mapping:

Key	Value
"en"	"Welcome to Wikipedia"
"de"	"Willkommen bei Wikipedia"
"fr"	"Bienvenue sur Wikipédia"
"nl"	"Welkom op Wikipedia"
"it"	"Benvenuti su Wikipedia"
"es"	"Bienvenidos a Wikipedia"
"ru"	"Добро пожаловать в Википедию"

Example

An example TemplateData structure as specified within wikitext on a template page.

<templatedata>
{
    "description": "Label unsigned comments in a conversation.",
    "params": {
        "user": {
            "label": "User's name",
            "type": "wiki-user-name",
            "required": true,
            "description": "User name of person who forgot to sign their comment.",
            "aliases": ["1"]
        },
        "date": {
            "label": "Date",
            "suggested": true,
            "description": {
                "en": "Timestamp of when the comment was posted, in YYYY-MM-DD format."
            },
            "aliases": ["2"],
            "autovalue": "{{subst:#time:Y-m-d}}"
        },
        "year": {
            "label": "Year",
            "type": "number"
        },
        "month": {
            "label": "Month",
            "inherits": "year"
        },
        "day": {
            "label": "Day",
            "inherits": "year"
        },
        "comment": {
            "required": false
        }
    },
    "sets": [
        {
            "label": "Date",
            "params": ["year", "month", "day"]
        }
    ],
    "maps": {
        "ExampleConsumer": {
            "foo": "user",
            "bar": ["year", "month", "day"],
            "quux": [
                "date",
                ["day", "month"],
                ["month", "year"],
                "year"
            ]
        }
    }
}
</templatedata>

Below is how the above example would be displayed on the template page:

Label unsigned comments in a conversation.

Template parameters[Edit template data]
Parameter		Description	Type	Status
User's name	`user` `1`	User name of person who forgot to sign their comment.	User	required
Date	`date` `2`	Timestamp of when the comment was posted, in YYYY-MM-DD format. Auto value `{{subst:#time:Y-m-d}}`	Unknown	suggested
Year	`year`	no description	Number	optional
Month	`month`	no description	Number	optional
Day	`day`	no description	Number	optional
comment	`comment`	no description	Unknown	optional

API

See the generated help at Special:ApiHelp/templatedata. A sample invocation (formatted for human readability) is:

api.php?action=templatedata&titles=Template:Cite%20web&format=json [try in ApiSandbox]

This returns the template data for Template:Cite web. The ‎<templatedata>...‎</templatedata> block for this template is on its transcluded template documentation page, en:Template:Cite web/doc.

Additions and changes to JSON as received from the API

The JSON structure provided in response to an API HTTP get request is significantly different than that which is defined in the ‎<templatedata>...‎</templatedata> block. In response to the API request, extension TemplateData makes the following changes to the JSON object:

Adds two wrapping objects:
1. An overall Pages Object containing one or more Page Objects
2. An object with a numeric key: a Page Object
Additions/changes to the actual TemplateData Object
1. Add the title key with the name of the page from which the data was requested (e.g. "Template:Cite web").
2. Add the sets key
3. Change all TemplateText occurrences that are just strings to objects with a single key for the current wiki's Wikipedia language code
4. Remove all inherits keys.
  - Add all properties from parameter from which an inheritance is defined which are not superseded by explicitly defined keys in the inheritor's Parameter Object.
5. Add default values for all keys in each Parameter Object which have not been explicitly defined or inherited.

Visualised differences in a TemplateData JSON object delivered by the API

JSON Root
Key	Type	Description
`pages`	Page Object	The Page object (contains one key which is the page number). If multiple pages were requested at one time there will be multiple Page Objects.

Page Object
Key	Type	Description
(page number)	TemplateData Object	The TemplateData Object containing the information payload. The key is a static page number for the template page from which the JSON data was requested.

TemplateData Object (added by API)
The following key is added to the root of the JSON object which is enclosed in `‎<templatedata>` tags on the template page.
Key	Type	Description
`title`	string	The page name of the template (e.g. "Template:Cite web"). This key is not contained in the JSON structure on the template page. It is added to the structure by the MediaWiki software in route to delivery via the API.
`sets`	Array containing Set Objects	An array containing set specifications. A set is a group of parameters that should be used together. If this does not exist on the template page it is added as an empty array to the structure provided by the API.

Parameter Objects from API
Key	Type	Description
`label`	InterfaceText	translated to InterfaceText object, if not already in that format.
`required`	boolean	If not defined, default value of false added.
`description`	InterfaceText or `null`	If defined as a string, converted to a InterfaceText object. If not defined, key is added with a `null` value.
`deprecated`	boolean or string	If not defined, default value of false added.
`aliases`	Array of strings	If not defined, a default empty array is assigned (i.e. [] ).
`default`	string	If not defined, default of "" is assigned.
`type`	string	If not defined, default of "unknown" is assigned.
`inherits`	(removed)	This key is removed and all inherited keys are added. Keys defined for the current parameter take precedence and any keys not defined on either the current param, or the one from which it inherits are given the default value.

InterfaceText (Object or `null`):
An object containing strings keyed by language code.
Key	Object or primitive type	Description
Object (containing localized strings by Wikipedia language code) If a TemplateData field on the template page contains a string, not an object with localized strings, MediaWiki translates it into an InterfaceText Object with a string assigned to the key name of the source Wikipedia Wikipedia language code. The default for all InterfaceText fields is `null`.
(Wiki language code)	string	Localized string for users of that interface language.

Example of JSON object provided by API

The response to an API request for the TemplateData structure in the Example section (above) can be seen:

In HTML format: https://www.mediawiki.org/w/api.php?action=templatedata&titles=Extension:TemplateData&format=jsonfm
As delivered by the API: https://www.mediawiki.org/w/api.php?action=templatedata&titles=Extension:TemplateData

Configuration

Variable	Default	Description
`$wgTemplateDataUseGUI`	`true`	Experimental dialog interface to edit templatedata JSON
`$wgTemplateDataEditorNamespaces`	`[ 10 ]`	The namespaces in which the template data editor appears when creating or editing a page. (task T189989)

TemplateData Release status: stable

Implementation	Tag , API
Description	Allows to store, retrieve and visualise information about templates
Author(s)	Timo Tijhof, Moriel Schottlender, James Forrester, Trevor Parscal, Bartosz Dziewoński, Marielle Volz, ...
Latest version	0.1.2 (Continuous updates)
Compatibility policy	Snapshots releases along with MediaWiki. Master is not backward compatible.
PHP	5.4+
Database changes	No
License	GNU General Public License 2.0 or later
Download	Download extension Git ^[?]: Download Git master browse repository (Phabricator · GitHub) commit history repository contributors (GitHub) code review
Help	Help:Extension:TemplateData
Parameters $wgTemplateDataEditorNamespaces $wgTemplateDataUseGUI
Tags `‎<templatedata>`
Hooks used EditPage::showEditForm:fields EditPage::showEditForm:initial MultiContentSave OutputPageBeforeHTML ParserFetchTemplateData ParserFirstCallInit ResourceLoaderRegisterModules
Quarterly downloads	285 (Ranked 15^th)
Public wikis using	6,971 (Ranked 24^th)
Translate the TemplateData extension if it is available at translatewiki.net
Issues	Open tasks · Report a bug

Installation

Editing data

Format

TemplateData object

Param object

Set object

Maps structure

InterfaceText (string or object)

String type

Object type

Example

API

Additions and changes to JSON as received from the API

Visualised differences in a TemplateData JSON object delivered by the API

Example of JSON object provided by API

Configuration

See also