STAC and coverages endpoints are duplicated in OpenAPI page

[pont-us]

For compatibility with a range of clients, STAC and coverages endpoints need to support URLs both with and without a trailing slash. Due to time pressure during OGC Testbed-19, this was implemented very simplistically by adding an extra api.route decorator to the implementations, e.g.

@api.route(PATH_PREFIX + "/collections")
@api.route(PATH_PREFIX + "/collections/")
class CatalogCollectionsHandler(ApiHandler[StacContext]):
    …

In source code this is non-DRY, and in deployment it has the unfortunate effect of duplicating the generated OpenAPI documentation for every endpoint:

Slash / no-slash handling should be implemented in a way that avoids cut-and-paste source code and duplicated OpenAPI entries.

[forman]

My preferred solution:

@api.route("ogc/collections/{collectionId}/coverage", slash=True)
class CoveragesCoverageHandler(ApiHandler[CoveragesContext]):
    ...

where slash=True adds an internal (!) second route with a trailing slash or it causes a redirect. For implementation https://www.tornadoweb.org/en/stable/web.html#tornado.web.addslash and https://www.tornadoweb.org/en/stable/web.html#tornado.web.removeslash might be useful.