A #swagger #geojson geometry description

geometry_geojson.yaml

#MIT License
#
#Copyright (c) 2017 Daniele Andreis
#Permission is hereby granted, free of charge, to any person obtaining a copy
#of this software and associated documentation files (the "Software"), to deal
#in the Software without restriction, including without limitation the rights
#to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
#copies of the Software, and to permit persons to whom the Software is
#furnished to do so, subject to the following conditions:
#
#
#The above copyright notice and this permission notice shall be included in all
#copies or substantial portions of the Software.
#
#THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
#IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
#FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
#AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
#LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
#OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
#SOFTWARE.

swagger: '2.0'
info:
  version: "1.0.0"
  title: GeoJSON geometry
  description: An example of swagger file for a geographic API. It contains the geometry definitions
  termsOfService: "no"
  contact: 
    name:  Daniele Andreis
    email: daniele.andreis@gmail.com
    url: ""
  license: 
    name: MIT
    url: https://opensource.org/licenses/mit-license.php
externalDocs: 
  description: find more info here
  url: http://geojson.org/geojson-spec.html#geometry-objects
schemes:
  - http
host: myHost
basePath: /v1
consumes:
  - "application/json"
produces: 
  - "application/json"

securityDefinitions:
  UserSecurity:
    type: basic
  # AdminSecurity:
  #   type: basic
  # MediaSecurity:
  #   type: basic
#globalmente e' userSecurity ma posso cambiare localmente

security:
  - UserSecurity: [] 

paths:
  /geometries:
    get:
      summary: GeoJSON geometry array
      description: 
      responses:
        200:
          description: Successful response
          schema:
             type: array
             items:
               $ref: "#/definitions/Geometry<Collection"
        
        400:
          $ref: "#/responses/BadRequest400ErrorResponse"
        401:
          $ref: "#/responses/Unauthorized401ErrorResponse"
        500:
          $ref: "#/responses/Standard500ErrorResponse"
          
    post:
      summary: Create new geometry
      description: 
      parameters:
        - name: geom
          in: body
          required: true
          schema:
            $ref: "#/definitions/Geometry"
      responses:
        201:
          description: new geometry created 
        400:
          $ref: "#/responses/BadRequest400ErrorResponse"
        401:
          $ref: "#/responses/Unauthorized401ErrorResponse"
        403:
          $ref: "#/responses/Forbidden403ErrorResponse"
        500:
          $ref: "#/responses/Standard500ErrorResponse"
     
definitions:
  Error:
    required:
      - code
      - message
    properties:
      code:
        type: string
      message:
        type: string   
        
  Geometry:
    type: object
    description: GeoJSon geometry
    discriminator: type
    required:
      - type
    externalDocs:
      url: http://geojson.org/geojson-spec.html#geometry-objects
    properties:
      type:
        type: string
        enum:
        - Point
        - LineString
        - Polygon
        - MultiPoint
        - MultiLineString
        - MultiPolygon
        description: the geometry type
  
  Point2D:
    type: array
    maxItems: 2
    minItems: 2
    items:
      type: number
  
  
  Point:
    type: object
    description: GeoJSon geometry
    externalDocs:
      url: http://geojson.org/geojson-spec.html#id2
    allOf:
      - $ref: "#/definitions/Geometry"
      - properties:
          coordinates:
            $ref: '#/definitions/Point2D'
    
  LineString:
    type: object
    description: GeoJSon geometry
    externalDocs:
      url: http://geojson.org/geojson-spec.html#id3
    allOf:
      - $ref: "#/definitions/Geometry"
      - properties:
          coordinates:
            type: array
            items:
              $ref: '#/definitions/Point2D'

  Polygon:
    type: object
    description: GeoJSon geometry
    externalDocs:
      url: http://geojson.org/geojson-spec.html#id4
    allOf:
      - $ref: "#/definitions/Geometry"
      - properties:
          coordinates:
            type: array
            items:
              type: array
              items:
                $ref: '#/definitions/Point2D'
      
  MultiPoint:
    type: object
    description: GeoJSon geometry
    externalDocs:
      url: http://geojson.org/geojson-spec.html#id5
    allOf:
      - $ref: "#/definitions/Geometry"
      - properties:
          coordinates:
            type: array
            items:
              $ref: '#/definitions/Point2D'
            
 MultiLineString:
    type: object
    description:GeoJSon geometry
    externalDocs:
      url: http://geojson.org/geojson-spec.html#id6
    allOf:
      - $ref: "#/definitions/Geometry"   
      - properties:
          coordinates:
            type: array
            items:
              type: array
              items:
                $ref: '#/definitions/Point2D'
      
      
  MultiPolygon:
    type: object
    description:GeoJSon geometry
    externalDocs:
      url: http://geojson.org/geojson-spec.html#id6
    allOf:
      - $ref: "#/definitions/Geometry"
      - properties:
          coordinates:
            type: array
            items:
              type: array
              items:
                type: array
                items:
                  $ref: '#/definitions/Point2D'
      
  GeometryCollection:
    type: object
    description:GeoJSon geometry collection
    required:
     - type
     - geometries
    externalDocs:
      url: http://geojson.org/geojson-spec.html#geometrycollection
    properties:
      type:
        type: string
        enum:
        - GeometryCollection
        description: 
      geometries:
          type: array
          items:
            $ref: '#/definitions/Geometry'

 responses:
  Standard500ErrorResponse:
    description: An unexpected error occured.
    schema:
      $ref: "#/definitions/Error"
      
  BadRequest400ErrorResponse:
    description: The JSON is not valid
    schema:
      $ref: "#/definitions/Error"
 
  Unauthorized401ErrorResponse:
    description: The request requires an user authentication
    schema:
      $ref: "#/definitions/Error"
      
  Forbidden403ErrorResponse:
    description: the access is not allowed
    schema:
      $ref: "#/definitions/Error"
      
  # NotFound404ErrorResponse:
  #   description: not found check the path or the query
  #   schema:
  #     $ref: "#/definitions/Error"
      
  # Ok200Response:
  #   description: Eyerything is working
  #   schema:
  #     $ref: "#/definitions/OK"

  # Create201Response:
  #   description:  New resource has been created
  #   schema:
  #     $ref: "#/definitions/OK"

  # Delete204Response:
  #   description: The resource was successfully deleted
  #   schema:
#     $ref: "#/definitions/OK"

Here is an OpenAPI 3 definition of the RFC-7946 GeoJSON objects specification:
https://gist.github.com/zit0un/3ac0575eb0f3aabdc645c3faad47ab4a
It includes Features and FeatureCollection as well as inheritance between the different objects.
You might want to check it and update your file if you need.

Thank you for helping me not start from scratch ;)