Validate fields in item assets, item assets defintion and collection assets; add link back to stac-spec

Author: m-mohr

README.md

@@ -7,6 +7,7 @@
 - **Extension [Maturity Classification](https://github.com/radiantearth/stac-spec/tree/master/extensions/README.md#extension-maturity):** Proposal
 - **Owner**: @your-gh-handles @person2
 
+This document explains the Template Extension to the [SpatioTemporal Asset Catalog](https://github.com/radiantearth/stac-spec) (STAC) specification.
 This is the place to add a short introduction.
 
 - Examples:
@@ -18,7 +19,8 @@ This is the place to add a short introduction.
 
 | Field Name  | Type                      | Description |
 | ----------- | ------------------------- | ----------- |
-| new_field   | [XYZ Object](#xyz-object) | **REQUIRED**. Describe the required field... |
+| new_field   | string                    | **REQUIRED**. Describe the required field... |
+| xyz         | [XYZ Object](#xyz-object) | Describe the field... |
 | another_one | \[number]                 | Describe the field... |
 
 ### Additional Field Information

examples/collection.json

@@ -1,6 +1,8 @@
 {
   "stac_version": "1.0.0-rc.1",
   "stac_extensions": [
+    "collection-assets",
+    "item-assets",
     "https://stac-extensions.github.io/template/v1.0.0/schema.json"
   ],
   "type": "Collection",
@@ -28,7 +30,8 @@
       ]
     }
   },
-  "new_field": {
+  "new_field": "test",
+  "xyz": {
     "x": 1,
     "y": 2,
     "z": 3
@@ -38,6 +41,17 @@
     2,
     3
   ],
+  "assets": {
+    "example": {
+      "href": "https://example.com/examples/file.xyz",
+      "new_field": "test"
+    }
+  },
+  "item_assets": {
+    "data": {
+      "new_field": "test"
+    }
+  },
   "summaries": {
     "datetime": {
       "minimum": "2015-06-23T00:00:00Z",
@@ -48,6 +62,10 @@
     {
       "href": "https://example.com/examples/collection.json",
       "rel": "self"
+    },
+    {
+      "href": "https://example.com/examples/item.json",
+      "rel": "item"
     }
   ]
 }

examples/item.json

@@ -40,7 +40,8 @@
   },
   "properties": {
     "datetime": "2020-12-11T22:38:32Z",
-    "new_field": {
+    "new_field": "test",
+    "xyz": {
       "x": 1,
       "y": 2,
       "z": 3
@@ -59,7 +60,8 @@
   ],
   "assets": {
     "data": {
-      "href": "https://example.com/examples/file.xyz"
+      "href": "https://example.com/examples/file.xyz",
+      "new_field": "test"
     }
   }
 }

json-schema/schema.json

@@ -5,35 +5,46 @@
   "description": "STAC Template Extension for STAC Items and STAC Collections.",
   "oneOf": [
     {
+      "$comment": "This is the schema for STAC Items.",
       "allOf": [
         {
           "type": "object",
           "required": [
-            "type"
+            "type",
+            "properties",
+            "assets"
           ],
           "properties": {
             "type": {
               "const": "Feature"
+            },
+            "properties": {
+              "allOf": [
+                {
+                  "required": [
+                    "new_field"
+                  ]
+                },
+                {
+                  "$ref": "#/definitions/fields"
+                }
+              ]
+            },
+            "assets": {
+              "type": "object",
+              "additionalProperties": {
+                "$ref": "#/definitions/fields"
+              }
             }
           }
         },
         {
           "$ref": "#/definitions/stac_extensions"
-        },
-        {
-          "type": "object",
-          "required": [
-            "properties"
-          ],
-          "properties": {
-            "properties": {
-              "$ref": "#/definitions/template"
-            }
-          }
         }
       ]
     },
     {
+      "$comment": "This is the schema for STAC Collections.",
       "allOf": [
         {
           "type": "object",
@@ -43,14 +54,26 @@
           "properties": {
             "type": {
               "const": "Collection"
+            },
+            "assets": {
+              "type": "object",
+              "additionalProperties": {
+                "$ref": "#/definitions/fields"
+              }
+            },
+            "item_assets": {
+              "type": "object",
+              "additionalProperties": {
+                "$ref": "#/definitions/fields"
+              }
             }
           }
         },
         {
           "$ref": "#/definitions/stac_extensions"
         },
         {
-          "$ref": "#/definitions/template"
+          "$ref": "#/definitions/fields"
         }
       ]
     }
@@ -70,14 +93,31 @@
         }
       }
     },
-    "template": {
+    "fields": {
+      "$comment": "Add your new fields here. Don't require them here, do that above in the item schema.",
       "type": "object",
-      "required": [
-        "new_field"
-      ],
       "properties": {
         "new_field": {
-          "$ref": "#/definitions/xyz_object"
+          "type": "string"
+        },
+        "xyz": {
+          "type": "object",
+          "required": [
+            "x",
+            "y",
+            "z"
+          ],
+          "properties": {
+            "x": {
+              "type": "number"
+            },
+            "y": {
+              "type": "number"
+            },
+            "z": {
+              "type": "number"
+            }
+          }
         }, 
         "another_one": {
           "type": "array", 
@@ -86,25 +126,6 @@
           }
         }
       }
-    },
-    "xyz_object": {
-      "type": "object",
-      "required": [
-        "x",
-        "y",
-        "z"
-      ],
-      "properties": {
-        "x": {
-          "type": "number"
-        },
-        "y": {
-          "type": "number"
-        },
-        "z": {
-          "type": "number"
-        }
-      }
     }
   }
 }