Added the OSM [ref](http://wiki.openstreetmap.org/wiki/Key:ref) tag of the runway/taxiway so that they can be displayed in styles.

layers/aeroway/aeroway.yaml

@@ -6,6 +6,7 @@ layer:
       other airport related polygons can be found in the **aeroway** layer.
   buffer_size: 4
   fields:
+    ref: The OSM [`ref`](http://wiki.openstreetmap.org/wiki/Key:ref) tag of the runway/taxiway.
     class:
       description: |
           The original value of the [`aeroway`](http://wiki.openstreetmap.org/wiki/Key:aeroway) tag.
@@ -18,7 +19,7 @@ layer:
       - apron
   datasource:
     geometry_field: geometry
-    query: (SELECT geometry, class FROM layer_aeroway(!bbox!, z(!scale_denominator!))) AS t
+    query: (SELECT geometry, ref, class FROM layer_aeroway(!bbox!, z(!scale_denominator!))) AS t
 schema:
   - ./layer.sql
 datasources:

layers/aeroway/layer.sql

@@ -2,25 +2,25 @@
 -- etldoc:     label="layer_aeroway |<z11> z11|<z12> z12|<z13> z13|<z14_> z14+" ];
 
 CREATE OR REPLACE FUNCTION layer_aeroway(bbox geometry, zoom_level int)
-RETURNS TABLE(geometry geometry, class text) AS $$
+RETURNS TABLE(geometry geometry, class text, ref text) AS $$
-    SELECT geometry, aeroway AS class FROM (
+    SELECT geometry, aeroway AS class, ref FROM (
         -- etldoc:  osm_aeroway_linestring -> layer_aeroway:z11
         -- etldoc:  osm_aeroway_linestring -> layer_aeroway:z12
         -- etldoc:  osm_aeroway_linestring -> layer_aeroway:z13
         -- etldoc:  osm_aeroway_linestring -> layer_aeroway:z14_
-        SELECT geometry, aeroway
+        SELECT geometry, aeroway, ref
         FROM osm_aeroway_linestring WHERE zoom_level >= 11
         UNION ALL
         -- etldoc:  osm_aeroway_polygon_gen2 -> layer_aeroway:z12
-        SELECT geometry, aeroway
+        SELECT geometry, aeroway, ref
         FROM osm_aeroway_polygon_gen2 WHERE zoom_level = 12
         UNION ALL
         -- etldoc:  osm_aeroway_polygon_gen1 -> layer_aeroway:z13
-        SELECT geometry, aeroway
+        SELECT geometry, aeroway, ref
         FROM osm_aeroway_polygon_gen1 WHERE zoom_level = 13
         UNION ALL
         -- etldoc:  osm_aeroway_polygon -> layer_aeroway:z14_
-        SELECT geometry, aeroway
+        SELECT geometry, aeroway, ref
         FROM osm_aeroway_polygon WHERE zoom_level >= 14
     ) AS zoom_levels
     WHERE geometry && bbox;

layers/aeroway/mapping.yaml

@@ -16,11 +16,18 @@ generalized_tables:
     source: aeroway_polygon
     sql_filter: area>power(ZRES12,2)
     tolerance: ZRES13
+
+ref_field: &ref
+  key: ref
+  name: ref
+  type: string
+
 tables:
   # etldoc: imposm3 -> osm_aeroway_polygon
   aeroway_polygon:
     type: polygon
     fields:
+    - *ref
     - name: osm_id
       type: id
     - name: geometry
@@ -45,6 +52,7 @@ tables:
   aeroway_linestring:
     type: linestring
     fields:
+    - *ref
     - name: osm_id
       type: id
     - name: geometry