Help:Map Data/en

Map data allows users to store GeoJSON data on wiki, similar to images. Other wikis may use this data to draw on top of the maps, together with other map customizations.

To create a new map data, go to Wikimedia Commons, and create a new page in the Data namespace with the .map suffix, such as. Feel free to experiment by creating pages with the Sandbox/&lt;username>/ prefix. For now, page content can only be edited in the raw JSON format. Eventually, we hope there will be a powerful editor to simplify GeoJSON creation (you can enable the c:User:0x010C/KartoEditor gadget to edit them directly or use the geojson website and then copy the GeoJSON data).

Data licensing
All data in the  namespace must licensed under one of the following licences: The default license is empty string (e.g invalid license) and when a user tries to save page with invalid license, they will be notified of the allowed licenses.
 * CC0-1.0
 * CC-BY versions: CC-BY-1.0, CC-BY-2.0, CC-BY-2.5, CC-BY-3.0, CC-BY-4.0, CC-BY-4.0+
 * CC-BY-SA versions: CC-BY-SA-1.0, CC-BY-SA-2.0, CC-BY-SA-2.5, CC-BY-SA-3.0, CC-BY-SA-4.0, CC-BY-SA-4.0+
 * ODbL-1.0

Top-level fields
Map data has several required and optional top-level elements:
 * The required  field must always be set to one of the allowed string values, e.g.   (see ).
 * The optional  field must be set to a localized string value - an object with at least one key-value, where the key is a language code (e.g. "en"), and the value is a description string.
 * The optional  field must be a Wiki markup string value that describes the source of the map data.
 * The optional  field must be an integer between 0 and 18. This value is only used for displaying map on its own page, not when including it in the articles.
 * The optional  and   fields specify the center of the map when displaying it on its own page, not when including it in the articles.
 * The required  field must be set to the valid GeoJSON content. Per GeoJSON specification,   field may be set for every Feature object. The map data will use all of the Simple Style properties, such as ,  ,   (color), and others. Additionally, the   and   fields may be either strings or localized string objects (similar to the localized type in tabular data). This allows the same map data to appear differently depending on the user's language.

Usage

 * Use  and   tags to show a map together with the custom map data defined in the .map page. For that, add this wiki markup (or similar
 * While not a very common usage scenario, a Lua script on any wiki can get map data by calling . The function returns data in almost the same format as the original JSON, except that all localized strings will be converted to regular strings, and the license field will also include a localized license name. To get the data in another language, pass language code as the second parameter. To get the data in the original, unmodified form, use "_" as the language code.

Examples
 { "type": "ExternalData", "service": "page", "title": "Neighbourhoods/New York City.map" }

Restrictions and gotchas

 * Each string value except the  must be no more than 400 symbols long. Special characters like new lines   and tabs   are not allowed.
 * The overall size of the page may not exceed 2MB.
 * Retrieving lines or shapes via Wikidata IDs within a data page will cause the map to break when it is called via maplink or mapframe. A workaround is to add the IDs directly in the maplink or mapframe code:

The sources are drawn in the order in which they are listed in the code - in the example above, the geoshape from Wikidata will appear beneath the components from the data page. This would be reversed if the data page was called before the Wikidata ID.