add conformance table

README.md

@@ -6,41 +6,35 @@ This repository contains a linter for OGC Features and Geometries JSON (JSON-FG)
 
 The linter rules are based on JSON-FG requirements classes [Core](https://docs.ogc.org/DRAFTS/21-045.html#rc_core), [3D](https://docs.ogc.org/DRAFTS/21-045.html#rc_3d) and [Features types and Schemas](https://docs.ogc.org/DRAFTS/21-045.html#rc_types-schemas). In addition, the linter does some consistency checks that are useful but not based on explicit requirements.
 
-In addition to requirements that can be validated with the JSON-FG JSON Schema, the following rules are also implemented. When based on JSON-FG requirements or recommendations this is stated in the list.
+The following table gives an overview of supported JSON-FG requirements. The codes in the Rules column are the 
+requirement names as listed in the OGC standard document. The table mentions separate sub requirements (e.g. "A", "B") only when some are and some are not supported.
+
+| Rule                                      | Supported | Description |
+| :-----------------------------------------| :--------:| ----------- |
+| /req/core/schema-valid                    | **yes**   | JSON Schema validation |
+| /rec/core/properties                      | no        | GeoJSON compatibility mode |
+| /req/core/metadata                        | **yes**   | Presence of conformance statement |
+| /req/core/instant                         | **yes**   | Valid dates / times in instants |
+| /req/core/interval                        | **yes**   | Valid dates / times in intervals |
+| /req/core/instant-and-interval            | **yes**   | Consistancy between instant and interval |
+| interval start is before interval end     | **yes**   | This is checked in addition to the official requirements |
+| /req/core/utc                             | **yes**   | Always UTC ("Z") timezone |
+| /req/core/coordinate-dimension            | **yes**   | All positions in a geometry have the same dimension |
+| /req/core/geometry-wgs84                  | **yes**   | WGS84 geometries within range |
+| /req/core/geom-valid                      | no        | Validity  of geometries |
+| /req/core/place                           | **yes**   | No valid GeoJSON geometries in `place` |
+| /req/core/geometry-collection             | **yes**   | All coordinates in a collection have the same CRS |
+| /req/core/fallback - A                    | **yes**   | Geometries in `geometry`  and `place` are not the same |
+| /req/core/fallback - B                    | no        | GeoJSOn compatibility is indicated in when the document is a GET response |
+| /req/core/axis-order                      | no        | Conformance to OGC axis order policy |
+| /rec/core/place-crs                       | no        | Coordinates in `place` within range of the used CRS |
+| /req/3d/metadata                          | **yes**   | Presence of conformance statement for 3D geometries |
+| /req/3d/coordinate-dimension              | **yes**   | All positions in a 3D geometry have 3 dimensions |
+| /req/3d/geom-valid                        | no        | Valid 3D geometries |
+| /req/types-schemas/metadata               | **yes**   | Presence of metadata conformance statement |
+| /req/types-schemas/feature-type           | **yes**   | Presence of `featureType` |
+| /req/types-schemas/geometry-dimension     | no        | Valid value of `geometryDimension` |
+| /rec/types-schemas/homogeneous-collection | no        | `featureType`  and `geometryDimension` stated on collection level when all are the same |
+| /req/types-schemas/feature-schemas        | no        | Referenced schemas must conform to OGC API Features part 5: Schemas |
+| /req/types-schemas/single-feature-schema  | no        | Consistency between feature schema and feature type |
 
-### time
-
-- Requirement 4B-C: validate type consistency for "interval" ends.
-- Requirement 5A-E: validate consistency between "date", "timestamp" and "interval".
-- Validate that interval start is before interval end ([spec issue](https://github.com/opengeospatial/ogc-feat-geo-json/issues/122)).
-
-### conformsTo (can be HTTP URI or Safe CURIE):
-
-- Validate that conformance with Core is stated - this must always be set
-- give a warning, if 3D conformance is stated but neither Polyhedron, MultiPolyhedron, Prism, nor MultiPrism is used
-- validate that 3D conformance is stated if Polyhedron, MultiPolyhedron, Prism, or MultiPrism geometries are present
-- give a warning, if Feature Types and Schemas conformance is stated but "featureType" is not used
-- validate that Feature Types and Schemas conformance is stated if "featureType" is present
-
-### all geometries:
-
-- Requirement 7: validate that all coordinates have the same dimension
-- Requirement 8A-B: validate that coordinates in the "geometry" member are within WGS84 bounds
-- Requirement 9: validate all GeoJSON geometries including embedded ones in a Prism using a library that supports Simple Features validation
-- Requirement 10: validate that there are no point, line string or polygon geometries in WGS 84 longitude/latitude in "place"
-- Requirement 11: validate that all coordinates within a geometry collection in a "place" member are in the same CRS
-- Requirement 12A: if both "geometry" and "place" are not null, validate that their values are not identical
-- Requirement 2 give a warning if positions in coordinates are outside the valid range for the CRS
-- validate that the coordinate dimension is consistent with the CRS (this is not currently a requirement, but makes sense as an additional test)
-- Requirement 10: validate that the geometries are consistent with the stated geometry dimension
-
-### 3D geometries:
-
-- Requirement 15: validate that Polyhedron and MultiPolyhedron geometries have a coordinate dimension of 3.
-- Requirement 16: validate for Polyhedron geometries that each shell is a composite and closed; voids must be in the outer shell
-
-### feature types and schemas:
-
-- Recommendation 3a: give a warning if all features in a feature collection have the same feature type and the feature type information is not specified on the collection.
-- Recommendation 3b: give a warning if all geometries in a feature collection have the same dimension and geometryDimension is not stated on the collection level.
-- Requirement 21: if a single feature schema is referenced, validate that all "featureType" members declare a single feature type and have the same value.