def mmi_to_shapefile(self, force_flag=False):
"""Convert grid.xml's mmi column to a vector shp file using ogr2ogr.
An ESRI shape file will be created.
:param force_flag: bool (Optional). Whether to force the regeneration
of the output file. Defaults to False.
:return: Path to the resulting tif file.
:rtype: str
Example of the ogr2ogr call we generate::
ogr2ogr -select mmi -a_srs EPSG:4326 mmi.shp mmi.vrt mmi
.. note:: It is assumed that ogr2ogr is in your path.
"""
LOGGER.debug('mmi_to_shapefile requested.')
shp_path = os.path.join(self.output_dir,
'%s-points.shp' % self.output_basename)
# Short circuit if the tif is already created.
if os.path.exists(shp_path) and force_flag is not True:
return shp_path
# Ensure the vrt mmi file exists (it will generate csv too if needed)
vrt_path = self.mmi_to_vrt(force_flag)
# now generate the tif using default interpolation options
binary_list = which('ogr2ogr')
LOGGER.debug('Path for ogr2ogr: %s' % binary_list)
if len(binary_list) < 1:
raise CallGDALError(
tr('ogr2ogr could not be found on your computer'))
# Use the first matching gdalwarp found
binary = binary_list[0]
command = (('%(ogr2ogr)s -overwrite -select mmi -a_srs EPSG:4326 '
'%(shp)s %(vrt)s mmi') % {
'ogr2ogr': binary,
'shp': shp_path,
'vrt': vrt_path
})
LOGGER.info('Created this ogr command:\n%s' % command)
# Now run ogr2ogr ...
# noinspection PyProtectedMember
self._run_command(command)
# Lastly copy over the standard qml (QGIS Style file) for the mmi.tif
qml_path = os.path.join(self.output_dir,
'%s-points.qml' % self.output_basename)
source_qml = resources_path('converter_data', 'mmi-shape.qml')
shutil.copyfile(source_qml, qml_path)
return shp_path
def _clip_raster_layer(
layer, extent, cell_size=None, extra_keywords=None):
"""Clip a Hazard or Exposure raster layer to the extents provided.
The layer must be a raster layer or an exception will be thrown.
.. note:: The extent *must* be in EPSG:4326.
The output layer will always be in WGS84/Geographic.
:param layer: A valid QGIS raster layer in EPSG:4326
:type layer: QgsRasterLayer
:param extent: An array representing the exposure layer
extents in the form [xmin, ymin, xmax, ymax]. It is assumed
that the coordinates are in EPSG:4326 although currently
no checks are made to enforce this.
or:
A QgsGeometry of type polygon.
**Polygon clipping currently only supported for vector datasets.**
:type extent: list(float), QgsGeometry
:param cell_size: Cell size (in GeoCRS) which the layer should
be resampled to. If not provided for a raster layer (i.e.
theCellSize=None), the native raster cell size will be used.
:type cell_size: float
:returns: Output clipped layer (placed in the system temp dir).
:rtype: QgsRasterLayer
:raises: InvalidProjectionError - if input layer is a density
layer in projected coordinates. See issue #123.
"""
if not layer or not extent:
message = tr('Layer or Extent passed to clip is None.')
raise InvalidParameterError(message)
if layer.type() != QgsMapLayer.RasterLayer:
message = tr(
'Expected a raster layer but received a %s.' %
str(layer.type()))
raise InvalidParameterError(message)
working_layer = layer.source()
# Check for existence of keywords file
base, _ = os.path.splitext(working_layer)
keywords_path = base + '.keywords'
message = tr(
'Input file to be clipped "%s" does not have the '
'expected keywords file %s' % (
working_layer,
keywords_path
))
verify(os.path.isfile(keywords_path), message)
# Raise exception if layer is projected and refers to density (issue #123)
# FIXME (Ole): Need to deal with it - e.g. by automatically reprojecting
# the layer at this point and setting the native resolution accordingly
# in its keywords.
keywords = read_file_keywords(keywords_path)
if 'datatype' in keywords and keywords['datatype'] == 'count':
if str(layer.crs().authid()) != 'EPSG:4326':
# This layer is not WGS84 geographic
message = (
'Layer %s represents count but has spatial reference "%s". '
'Count layers must be given in WGS84 geographic coordinates, '
'so please reproject and try again. For more information, see '
'issue https://github.com/AIFDR/inasafe/issues/123' % (
working_layer,
layer.crs().toProj4()
))
raise InvalidProjectionError(message)
# We need to provide gdalwarp with a dataset for the clip
# because unlike gdal_translate, it does not take projwin.
clip_kml = extent_to_kml(extent)
# Create a filename for the clipped, resampled and reprojected layer
handle, filename = tempfile.mkstemp('.tif', 'clip_', temp_dir())
os.close(handle)
os.remove(filename)
# If no cell size is specified, we need to run gdalwarp without
# specifying the output pixel size to ensure the raster dims
# remain consistent.
binary_list = which('gdalwarp')
LOGGER.debug('Path for gdalwarp: %s' % binary_list)
if len(binary_list) < 1:
raise CallGDALError(
tr('gdalwarp could not be found on your computer'))
# Use the first matching gdalwarp found
binary = binary_list[0]
if cell_size is None:
command = (
'"%s" -q -t_srs EPSG:4326 -r near -cutline %s -crop_to_cutline '
'-ot Float64 -of GTiff "%s" "%s"' % (
binary,
clip_kml,
working_layer,
filename))
else:
command = (
'"%s" -q -t_srs EPSG:4326 -r near -tr %s %s -cutline %s '
'-crop_to_cutline -ot Float64 -of GTiff "%s" "%s"' % (
binary,
repr(cell_size),
repr(cell_size),
clip_kml,
working_layer,
filename))
LOGGER.debug(command)
result = QProcess().execute(command)
# For QProcess exit codes see
# http://qt-project.org/doc/qt-4.8/qprocess.html#execute
if result == -2: # cannot be started
message_detail = tr('Process could not be started.')
message = tr(
'<p>Error while executing the following shell command:'
'</p><pre>%s</pre><p>Error message: %s'
% (command, message_detail))
raise CallGDALError(message)
elif result == -1: # process crashed
message_detail = tr('Process crashed.')
message = tr(
'<p>Error while executing the following shell command:</p>'
'<pre>%s</pre><p>Error message: %s' % (command, message_detail))
raise CallGDALError(message)
# .. todo:: Check the result of the shell call is ok
keyword_io = KeywordIO()
keyword_io.copy_keywords(layer, filename, extra_keywords=extra_keywords)
base_name = '%s clipped' % layer.name()
layer = QgsRasterLayer(filename, base_name)
return layer