example dataset for GeoJSON provider

pygeoapi-config.yml

@@ -90,3 +90,25 @@ datasets:
             type: Elasticsearch
             url: http://localhost:9200/index/type
             id_field: id_
+    lakes:
+        type: Polygon
+        title: Large Lakes
+        abstract: lakes of the world, public domain
+        keywords: lakes
+        crs:
+            - CRS84
+        links:
+            - type: information
+              url: http://www.naturalearthdata.com/
+            - type: download
+              url: http://www.naturalearthdata.com/
+        extents:
+            spatial:
+                bbox: [-180,-90,180,90]
+            temporal:
+                begin: 2011-11-11
+                end: now  # or empty
+        data:
+            type: GeoJSON
+            url: file://data/ne_110m_lakes.geojson
+            id_field: null  # null indicates use feature enumeration

pygeoapi/provider/geojson.py

@@ -96,9 +96,22 @@ class GeoJSONProvider(BaseProvider):
         collection = EMPTY_COLLECTION.copy()
 
         all_data = self._load()
-        for feature in all_data['features']:
-            if feature[self.id_field]:
-                collection['features'].append(feature)
+
+        if self.id_field:
+            # Use id field
+            for feature in all_data['features']:
+                if feature[self.id_field] == identifier:
+                    collection['features'].append(feature)
+        else:
+            # Use enumeration, zero-indexed
+            for i, feature in enumerate(all_data['features']):
+                if i == identifier:
+                    collection['features'].append(feature)
+
+        # assert that one and only one feature returned
+        n_features = len(collection['features'])
+        if n_features != 1:
+            raise RuntimeError('Expected 1 feature, got {}'.format(n_features))
 
         return collection