webmap-import: Major refactoring.

1 files changed, 18 insertions, 139 deletions

diff --git a/common.py b/common.py
index acbb5d8..0bece11 100644
--- a/common.py
+++ b/common.py
@@ -56,6 +56,13 @@ class MissingConfiguration(Exception):
     def __init__(self, name : str) -> Never:
         super().__init__(f'Could not find configuration file {name}')
 
+class BadConfiguration(Exception):
+    """Exception raised when there is a bad configuration"""
+    def __init__(self, message : str, config_path : Optional[Path] = None) -> Never:
+        if config_path is not None:
+            message = str(config_path) + ': ' + message
+        super().__init__(message)
+
 def find_config(filename : str = 'config.yml', appname : str = 'webmap') -> Path:
     """Return the configuration file path"""
     dirs = [
@@ -77,8 +84,16 @@ def parse_config(path : Optional[Path] = None,
     with config_path.open(mode='r', encoding='utf-8') as fp:
         config = yaml.safe_load(fp)
 
-    # filter layers that are not of interest
     layers = config.get('layers', {})
+    for name, layerdefs in layers.items():
+        if isinstance(layerdefs, dict) and 'sources' not in layerdefs:
+            layers[name] = { 'sources': [layerdefs] }
+            for k in ('description', 'create', 'publish'):
+                if k in layerdefs:
+                    layers[name][k] = layerdefs.pop(k)
+            layerdefs = layers[name]
+
+    # filter layers that are not of interest
     if groupnames is not None:
         layernames = []
         layer_groups = config.get('layer-groups', {})
@@ -123,8 +138,8 @@ def parse_config(path : Optional[Path] = None,
         if isinstance(extent, list):
             config['extent'] = tuple(extent)
         if config.get('SRS', None) is None:
-            # pylint: disable-next=broad-exception-raised
-            raise Exception('Configured extent without SRS')
+            raise BadConfiguration('Configured extent without SRS',
+                                   config_path=config_path)
 
     return config
 
@@ -149,142 +164,6 @@ def format_time(ts : float, precision : int = 3) -> str:
     h, m = divmod(m, 60)
     return f'{h:02d}:{m:02d}:{s:0{w}.{precision}f}'
 
-# pylint: disable-next=invalid-name, redefined-builtin
-def gdalVersionMin(gdal, maj : int = 0, min : int = 0, rev : int = 0) -> bool:
-    """Return a boolean indicating whether the installer GDAL version is
-       greater than or equal to the provider (maj, min, rev) triplet."""
-
-    if maj < 1 or (maj == 1 and min < 10):
-        # GDAL_VERSION_NUM() macro was changed in 1.10.  That version
-        # was released in 2013 so we blindly assume the installer
-        # version is more recent
-        return True
-
-    version_cur = int(gdal.VersionInfo())
-    # cf. GDAL_COMPUTE_VERSION(maj,min,rev) in gcore/gdal_version.h.in
-    version_min = maj*1000000 + min*10000 + rev*100
-    return version_min <= version_cur
-
-# pylint: disable-next=invalid-name
-def gdalGetMetadataItem(obj, k : str) -> bool:
-    """Wrapper around gdal.MajorObject.GetMetadataItem(name)."""
-
-    v = obj.GetMetadataItem(k)
-    if v is not None and isinstance(v, str):
-        return v.upper() == 'YES'
-
-    return False
-
-def escape_identifier(identifier : str) -> str:
-    """Escape the given identifier, cf.
-    swig/python/gdal-utils/osgeo_utils/samples/validate_gpkg.py:_esc_id()."""
-
-    if '\x00' in identifier:
-        # pylint: disable-next=broad-exception-raised
-        raise Exception(f'Invalid identifier "{identifier}"')
-
-    # SQL:1999 delimited identifier
-    return '"' + identifier.replace('"', '""') + '"'
-
-# pylint: disable-next=invalid-name,dangerous-default-value
-def gdalSetOpenExArgs(gdal, option_dict : Optional[dict[str, Any]] = {}, flags : int = 0):
-    """Return a pair kwargs and driver to use with gdal.OpenEx()."""
-
-    kwargs = { 'nOpenFlags': gdal.OF_VECTOR | flags }
-
-    fmt = option_dict.get('format', None)
-    if fmt is None:
-        drv = None
-    else:
-        drv = gdal.GetDriverByName(fmt)
-        if drv is None:
-            # pylint: disable-next=broad-exception-raised
-            raise Exception(f'Unknown driver name "{fmt}"')
-        if not gdalGetMetadataItem(drv, gdal.DCAP_VECTOR):
-            # pylint: disable-next=broad-exception-raised
-            raise Exception(f'Driver "{drv.ShortName}" has no vector capabilities')
-        kwargs['allowed_drivers'] = [ drv.ShortName ]
-
-    oo = option_dict.get('open-options', None)
-    if oo is not None:
-        kwargs['open_options'] = [ k + '=' + str(v) for k, v in oo.items() ]
-    return kwargs, drv
-
-# pylint: disable-next=invalid-name
-def getSRS(osr, srs_str : Optional[str]):
-    """Return the decoded Spatial Reference System."""
-
-    if srs_str is None:
-        return None
-
-    srs = osr.SpatialReference()
-    if srs_str.startswith('EPSG:'):
-        code = int(srs_str.removeprefix('EPSG:'))
-        srs.ImportFromEPSG(code)
-    else:
-        # pylint: disable-next=broad-exception-raised
-        raise Exception(f'Unknown SRS {srs_str}')
-
-    logging.debug('Default SRS: "%s" (%s)', srs.ExportToProj4(), srs.GetName())
-    return srs
-
-# pylint: disable-next=invalid-name
-def getExtent(extent : tuple[float, float, float, float] | list[float], srs = None):
-    """Convert extent [minX, minY, maxX, maxY] into a polygon and assign the
-    given SRS.  Return a pair with the densified and non-densified extent.
-    Like apps/ogr2ogr_lib.cpp, the former is obtained by segmentizing the
-    polygon to make sure it is sufficiently densified when transforming to
-    source layer SRS for spatial filtering."""
-
-    if extent is None:
-        return None, None
-
-    if not isinstance(extent, (list, tuple)) or len(extent) != 4:
-        # pylint: disable-next=broad-exception-raised
-        raise Exception(f'Invalid extent {extent}')
-    if srs is None:
-        # pylint: disable-next=broad-exception-raised
-        raise Exception('Configured extent but no SRS')
-
-    logging.debug('Configured extent in %s: %s',
-        srs.GetName(), ', '.join(map(str, extent)))
-
-    from osgeo import ogr, osr # pylint: disable=import-outside-toplevel
-    ogr.UseExceptions()
-
-    ring = ogr.Geometry(ogr.wkbLinearRing)
-    ring.AddPoint_2D(extent[0], extent[1])
-    ring.AddPoint_2D(extent[2], extent[1])
-    ring.AddPoint_2D(extent[2], extent[3])
-    ring.AddPoint_2D(extent[0], extent[3])
-    ring.AddPoint_2D(extent[0], extent[1])
-
-    polygon = ogr.Geometry(ogr.wkbPolygon)
-    polygon.AddGeometry(ring)
-
-    # we expressed extent as minX, minY, maxX, maxY (easting/northing
-    # ordered, i.e., in traditional GIS order)
-    srs2 = srs.Clone()
-    srs2.SetAxisMappingStrategy(osr.OAMS_TRADITIONAL_GIS_ORDER)
-    polygon.AssignSpatialReference(srs2)
-    if not srs2.IsSame(srs):
-        polygon.TransformTo(srs)
-
-    # densify the rectangle to avoid issues when reprojecting to the
-    # source layer SRS, cf. apps/ogr2ogr_lib.cpp:ApplySpatialFilter()
-    polygon_dense = polygon.Clone()
-    segment_distance_metre = 10 * 1000
-    if srs.IsGeographic():
-        # pylint: disable-next=invalid-name
-        dfMaxLength = segment_distance_metre / math.radians(srs.GetSemiMajor())
-        polygon_dense.Segmentize(dfMaxLength)
-    elif srs.IsProjected():
-        # pylint: disable-next=invalid-name
-        dfMaxLength = segment_distance_metre / srs.GetLinearUnits()
-        polygon_dense.Segmentize(dfMaxLength)
-
-    return polygon_dense, polygon
-
 
 ######
 # The function definitions below are taken from cpython's source code