maptiles/layers/barrier/barrier.yaml

layer:
  id: "barrier"
  description: |
    Barriers
  buffer_size: 4
  srs: +proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0 +y_0=0.0 +k=1.0 +units=m +nadgrids=@null +wktext +no_defs +over
  fields:
    subclass:
  datasource:
    geometry_field: geometry
    srid: 900913
    query: (SELECT geometry, subclass FROM layer_barrier(!bbox!, z(!scale_denominator!))) AS t
schema:
  - ./barrier.sql
datasources:
  - type: imposm3
    mapping_file: ./mapping.yaml