Add SQL and default value support for layers

omtgen.py

@@ -2,6 +2,7 @@
 """
 Usage:
   omtgen tm2source <tileset> [--host=<host>] [--port=<port>] [--database=<dbname>] [--user=<user>] [--password=<pw>]
+  omtgen dump-sql <tileset>
   omtgen --help
   omtgen --version
 Options:
@@ -13,6 +14,7 @@ Options:
   --user=<user>       PostGIS user.
   --password=<pw>     PostGIS password.
 """
+import os
 import sys
 import yaml
 import collections
@@ -22,17 +24,17 @@ DbParams = collections.namedtuple('DbParams', ['dbname', 'host', 'port',
                                                'password', 'user'])
 
 
-def generate_layer(layer_def, db_params):
+def generate_layer(layer_def, layer_defaults, db_params):
     layer = layer_def['layer']
     datasource = layer['datasource']
     tm2layer = {
         'id': layer['id'],
         'description': layer['description'],
-        'srs': layer['srs'],
+        'srs': layer.get('srs', layer_defaults['srs']),
         'properties': {
             'buffer-size': layer['buffer_size']
         },
-        'fields': layer['fields'],
+        'fields': layer.get('fields', []),
         'Datasource': {
           'extent': [-20037508.34, -20037508.34, 20037508.34, 20037508.34],
           'geometry_field': datasource.get('geometry_field', 'geom'),
@@ -40,7 +42,7 @@ def generate_layer(layer_def, db_params):
           'key_field_as_attribute': datasource.get('key_field_as_attribute', ''),
           'max_size': datasource.get('max_size', 512),
           'port': db_params.port,
-          'srid': datasource['srid'],
+          'srid': datasource.get('srid', layer_defaults['datasource']['srid']),
           'table': datasource['query'],
           'type': 'postgis',
           'host': db_params.host,
@@ -52,15 +54,37 @@ def generate_layer(layer_def, db_params):
     return tm2layer
 
 
-def generate_tm2source(tileset_filename, db_params):
-    with open(tileset_filename, 'r') as stream:
+def parse_tileset(filename):
+    with open(filename, 'r') as stream:
         try:
-            tileset = yaml.load(stream)['tileset']
+            return yaml.load(stream)['tileset']
         except yaml.YAMLError as e:
-            print('Could not parse ' + tileset_filename)
+            print('Could not parse ' + filename)
             print(e)
             sys.exit(403)
 
+
+def collect_sql(tileset_filename):
+    tileset = parse_tileset(tileset_filename)
+    print(tileset)
+    sql = ''
+    for layer_filename in tileset['layers']:
+        with open(layer_filename, 'r') as stream:
+            try:
+                layer_def = yaml.load(stream)
+                for sql_filename in layer_def['schema']:
+                    with open(os.path.join(os.path.dirname(layer_filename), sql_filename), 'r') as stream:
+                        sql += stream.read()
+            except yaml.YAMLError as e:
+                print('Could not parse ' + layer_filename)
+                print(e)
+                sys.exit(403)
+    return sql
+
+
+def generate_tm2source(tileset_filename, db_params):
+    tileset = parse_tileset(tileset_filename)
+    layer_defaults = tileset['defaults']
     tm2 = {
         'attribution': tileset['attribution'],
         'center': tileset['center'],
@@ -75,7 +99,7 @@ def generate_tm2source(tileset_filename, db_params):
         with open(layer_filename, 'r') as stream:
             try:
                 layer_def = yaml.load(stream)
-                tm2layer = generate_layer(layer_def, db_params)
+                tm2layer = generate_layer(layer_def, layer_defaults, db_params)
                 tm2['Layer'].append(tm2layer)
             except yaml.YAMLError as e:
                 print('Could not parse ' + layer_filename)
@@ -96,3 +120,6 @@ if __name__ == '__main__':
         )
         tm2 = generate_tm2source(args['<tileset>'], db_params)
         print(yaml.dump(tm2))
+    if args.get('dump-sql'):
+        sql = collect_sql(args['<tileset>'])
+        print(sql)