Find layers using default styles and generate independent styles for each

fixup_styles.py

#!/usr/bin/env python

from geoserver.catalog import Catalog

from itertools import cycle, izip
import re

_punc = re.compile(r"[\.:]") #regex for punctuation that confuses restconfig
_foregrounds = ["#ffbbbb", "#bbffbb", "#bbbbff", "#ffffbb", "#bbffff", "#ffbbff"]
_backgrounds = ["#880000", "#008800", "#000088", "#888800", "#008888", "#880088"]
_marks = ["square", "circle", "star", "cross", "x", "triangle"]
_style_contexts = izip(cycle(_foregrounds), cycle(_backgrounds), cycle(_marks))

def _add_sld_boilerplate(symbolizer):
    """
    Wrap an XML snippet representing a single symbolizer in the approperiate
    elements to make it a valid SLD which applies that symbolizer to all features,
    including format strings to allow interpolating a "name" variable in.
    """
    return """
<StyledLayerDescriptor version="1.0.0" xmlns="http://www.opengis.net/sld" xmlns:ogc="http://www.opengis.net/ogc"
  xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://www.opengis.net/sld http://schemas.opengis.net/sld/1.0.0/StyledLayerDescriptor.xsd">
  <NamedLayer>
    <Name>%(name)s</Name>
    <UserStyle>
    <Name>%(name)s</Name>
      <FeatureTypeStyle>
        <Rule>
""" + symbolizer + """
        </Rule>
      </FeatureTypeStyle>
    </UserStyle>
  </NamedLayer>
</StyledLayerDescriptor>
"""

_raster_template = """
<RasterSymbolizer>
    <Opacity>1.0</Opacity>
</RasterSymbolizer>
"""

_polygon_template = """
<PolygonSymbolizer>
  <Fill>
    <CssParameter name="fill">%(bg)s</CssParameter>
  </Fill>
  <Stroke>
    <CssParameter name="stroke">%(fg)s</CssParameter>
  </Stroke>
</PolygonSymbolizer>
"""


_line_template = """
<LineSymbolizer> 
  <Stroke>
    <CssParameter name="stroke">%(bg)s</CssParameter>
  </Stroke>
</LineSymbolizer>
<LineSymbolizer>
  <Stroke>
    <CssParameter name="stroke">%(fg)s</CssParameter>
    <CssParameter name="stroke-dasharray">2 2</CssParameter>
  </Stroke>
</LineSymbolizer>
"""

_point_template = """
<PointSymbolizer>
  <Graphic>
    <Mark>
      <WellKnownName>%(mark)s</WellKnownName>
      <Fill>
        <CssParameter name="fill">%(bg)s</CssParameter>
      </Fill>
      <Stroke>
        <CssParameter name="stroke">%(fg)s</CssParameter>
      </Stroke>
    </Mark>
    <Size>10</Size>
  </Graphic>
</PointSymbolizer>
"""

_style_templates = dict(
    raster = _add_sld_boilerplate(_raster_template),
    polygon = _add_sld_boilerplate(_polygon_template),
    line = _add_sld_boilerplate(_line_template),
    point = _add_sld_boilerplate(_point_template)
)

def _style_name(lyr):
    return _punc.sub("_", lyr.name)

if __name__ == "__main__":
    cat = Catalog("http://localhost:8080/geoserver/rest", "admin", "geoserver")
    for lyr in cat.get_layers():
        if lyr.default_style.name in _style_templates:
            print lyr, "uses a default style, generating a new one"
            name = lyr.name
            fg, bg, mark = _style_contexts.next()
            sld = _style_templates[lyr.default_style.name] % dict(name=name, fg=fg, bg=bg, mark=mark)
            style = cat.create_style(name, sld)
            lyr.default_style = cat.get_style(name)
            cat.save(lyr)