As a Wikidata reuser, I want to have a canonical URI scheme for EntitySchemas in order to identify them as concepts and access them in various formats e.g. RDF.
**Problem:**
EntitySchemas at Wikidata reside at the URL `https://www.wikidata.org/wiki/EntitySchema:EXX`, but this is not a canonical URI.
In order to identify EntitySchemas as concepts in RDF etc. we should have a canonical URI (prefix) just as we have for Items, Properties, and Lexemes.
`entity/QXX` with a redirect to `wiki/Special:EntityData/QXX` is currently being used for Items, Properties, and Lexemes. To make a predictable URI scheme this is the preferred prefix for EntitySchemas.
Once the URI has been developed, it should redirect to the actual content, as is does for Items, Properties, and Lexemes.
The link to the Concept URI should also be added to the EntitySchema sidebar
{F36888114}
**BDD**
GIVEN an EntitySchema
AND a RDF / JSON export for an Item or Lexeme
WHEN an EntitySchema is referenced in a statement
THEN the reference is a concept URI
**Acceptance criteria:**
[ ] EntitySchemas have a defined concept URI
[ ] The EntitySchema concept URI redirects to the EntitySchema URL (if HTML representation is requested)
[ ] A link to the Concept URI is added to the EntitySchema sidebar
**Open questions:**
**Notes**
https://www.wikidata.org/wiki/Wikidata:Data_access#Linked_Data_Interface_(URI)
There is a way to represent EntitySchemas as RDF, but this will be approached in the future.
**Original ticket**
ShEx schemas at Wikidata reside at `https://www.wikidata.org/wiki/EntitySchema:Exxx`, but this is not a canonical URI. We should have a canonical URI (prefix), and I guess `http://www.wikidata.org/entity/` would do, just as for Items, Properties, and Lexemes.
Once a URI prefix has been found:
* it should be documented whereever necessary
* `http://www.wikidata.org/entity/Exxx` (or whatever prefix is chosen) should redirect to actual content, as for Items, Properties, and Lexemes.
A canonical URI would likely be required for T225701, and the shex-simple tool could probably make use of it as well for relative URI resolution to a predictable absolute URI.