def getMapunitFeaturesForBoundingBox(config, outputDir, bbox, tileBbox=False, t_srs='EPSG:4326',
tileDivisor=SSURGO_BBOX_TILE_DIVISOR,
keepOriginals=False,
overwrite=True,
nprocesses=None):
""" Query USDA Soil Data Mart for SSURGO MapunitPolyExtended features with a given bounding box.
Features will be written to one or more shapefiles, one file for each bboxTile tile,
stored in the specified output directory. The filename will be returned as a string.
Will fetch SSURGO tabular data (see ssurgolib.attributequery.ATTRIBUTE_LIST for a list
of attributes) and join those data to the features in the final shapefiles(s).
@note Will silently exit if features already exist.
@param config onfigParser containing the section 'GDAL/OGR' and option 'PATH_OF_OGR2OGR'
@param outputDir String representing the absolute/relative path of the directory into which features should be written
@param bbox A dict containing keys: minX, minY, maxX, maxY, srs, where srs='EPSG:4326'
@param tileBoundingBox True if bounding box should be tiled if extent exceeds featurequery.MAX_SSURGO_EXTENT
@param t_srs String representing the spatial reference system of the output shapefiles, of the form 'EPSG:XXXX'
@param tileDivisor Float representing amount by which to divide tile slides.
@param keepOriginals Boolean, if True original feature layers will be retained (otherwise they will be deleted)
@param overwrite Boolean, if True any existing files will be overwritten
@param nprocesses Integer representing number of processes to use for fetching SSURGO tiles in parallel (used only if bounding box needs to be tiled).
if None, multiprocessing.cpu_count() will be used.
@return A list of strings representing the name of the shapefile(s) to which the mapunit features were saved.
@exception IOError if output directory is not a directory
@exception IOError if output directory is not writable
@exception Exception if tileDivisor is not a postive float > 0.0.
@exception Exception if bounding box area is greater than MAX_SSURGO_EXTENT
@exception Exception if no MUKEYs were returned
"""
if type(tileDivisor) != float or tileDivisor <= 0.0:
raise Exception("Tile divisor must be a float > 0.0.")
if not os.path.isdir(outputDir):
raise IOError(errno.ENOTDIR, "Output directory %s is not a directory" % (outputDir,))
if not os.access(outputDir, os.W_OK):
raise IOError(errno.EACCES, "Not allowed to write to output directory %s" % (outputDir,))
outputDir = os.path.abspath(outputDir)
typeName = 'MapunitPolyExtended'
if tileBbox:
bboxes = tileBoundingBox(bbox, MAX_SSURGO_EXTENT, t_srs, tileDivisor)
sys.stderr.write("Dividing bounding box %s into %d tiles\n" % (str(bbox), len(bboxes)))
else:
bboxArea = calculateBoundingBoxArea(bbox, t_srs)
if bboxArea > MAX_SSURGO_EXTENT:
raise Exception("Bounding box area %.2f sq. km is greater than %.2f sq. km. You must tile the bounding box." % (bboxArea/1000/1000, MAX_SSURGO_EXTENT/1000/1000,))
bboxes = [bbox]
numTiles = len(bboxes)
assert(numTiles >= 1)
outFiles = []
if numTiles == 1:
# No tiling, fetch SSURGO features for bbox in the current process
geojsonFilename = _getMapunitFeaturesForBoundingBoxTile(config, outputDir, bboxes[0], typeName, 1, numTiles)
outFiles.append(geojsonFilename)
else:
# Fetch SSURGO feature tiles in parallel
if nprocesses is None:
nprocesses = multiprocessing.cpu_count()
assert(type(nprocesses) == int)
assert(nprocesses > 0)
# Start my pool
pool = multiprocessing.Pool( nprocesses )
tasks = []
# Build task list
i = 1
for bboxTile in bboxes:
tasks.append( (config, outputDir, bboxTile, typeName, i, numTiles) )
i += 1
# Send tasks to pool (i.e. fetch SSURGO features for each tile in parallel)
results = [pool.apply_async(_getMapunitFeaturesForBoundingBoxTile, t) for t in tasks]
# Get resulting filenames for each tile
for result in results:
outFiles.append(result.get())
pool.close()
pool.join()
# Join tiled data if necessary
if len(outFiles) > 1:
sys.stderr.write('Merging tiled features to single shapefile...')
sys.stderr.flush()
shpFilepath = mergeFeatureLayers(config, outputDir, outFiles, typeName,
outFormat=OGR_SHAPEFILE_DRIVER_NAME,
keepOriginals=keepOriginals,
t_srs=t_srs,
overwrite=overwrite)
shpFilename = os.path.basename(shpFilepath)
sys.stderr.write('done\n')
else:
# Convert GeoJSON to shapefile
filepath = outFiles[0]
sys.stderr.write('Converting SSURGO features from GeoJSON to shapefile format...')
sys.stderr.flush()
shpFilename = convertGeoJSONToShapefile(config, outputDir, filepath, typeName, t_srs=t_srs)
os.unlink(filepath)
sys.stderr.write('done\n')
return shpFilename
def getMapunitFeaturesForBoundingBox(config, outputDir, bbox, tileBbox=False, t_srs='EPSG:4326'):
""" Query USDA Soil Data Mart for SSURGO MapunitPolyExtended features with a given bounding box.
Features will be written to one or more shapefiles, one file for each bboxTile tile,
stored in the specified output directory. The filename will be returned as a string.
Will fetch SSURGO tabular data (see ssurgolib.attributequery.ATTRIBUTE_LIST for a list
of attributes) and join those data to the features in the final shapefiles(s).
@note Will silently exit if features already exist.
@param config onfigParser containing the section 'GDAL/OGR' and option 'PATH_OF_OGR2OGR'
@param outputDir String representing the absolute/relative path of the directory into which features should be written
@param bbox A dict containing keys: minX, minY, maxX, maxY, srs, where srs='EPSG:4326'
@param tileBoundingBox True if bounding box should be tiled if extent exceeds featurequery.MAX_SSURGO_EXTENT
@param t_srs String representing the spatial reference system of the output shapefiles, of the form 'EPSG:XXXX'
@return A list of strings representing the name of the shapefile(s) to which the mapunit features were saved.
@exception IOError if output directory is not a directory
@exception IOError if output directory is not writable
@exception Exception if bounding box area is greater than MAX_SSURGO_EXTENT
@exception Exception if no MUKEYs were returned
"""
if not os.path.isdir(outputDir):
raise IOError(errno.ENOTDIR, "Output directory %s is not a directory" % (outputDir,))
if not os.access(outputDir, os.W_OK):
raise IOError(errno.EACCES, "Not allowed to write to output directory %s" % (outputDir,))
outputDir = os.path.abspath(outputDir)
typeName = 'MapunitPolyExtended'
if tileBbox:
bboxes = tileBoundingBox(bbox, MAX_SSURGO_EXTENT)
sys.stderr.write("Dividing bounding box %s into %d tiles\n" % (str(bbox), len(bboxes)))
else:
if calculateBoundingBoxArea(bbox, t_srs) > MAX_SSURGO_EXTENT:
raise Exception("Bounding box area is greater than %f sq. meters" % (MAX_SSURGO_EXTENT,))
bboxes = [bbox]
outFiles = []
for bboxTile in bboxes:
minX = bboxTile['minX']; minY = bboxTile['minY']; maxX = bboxTile['maxX']; maxY = bboxTile['maxY']
bboxLabel = str(minX) + "_" + str(minY) + "_" + str(maxX) + "_" + str(maxY)
gmlFilename = "%s_bbox_%s-attr.gml" % (typeName, bboxLabel)
gmlFilepath = os.path.join(outputDir, gmlFilename)
if not os.path.exists(gmlFilepath):
sys.stderr.write("Fetching SSURGO data for sub bboxTile %s\n" % bboxLabel)
wfs = WebFeatureService(WFS_URL, version='1.0.0')
filter = "<Filter><BBOX><PropertyName>Geometry</PropertyName> <Box srsName='EPSG:4326'><coordinates>%f,%f %f,%f</coordinates> </Box></BBOX></Filter>" % (minX, minY, maxX, maxY)
gml = wfs.getfeature(typename=(typeName,), filter=filter, propertyname=None)
# Write intermediate GML to a file
intGmlFilename = "%s_bbox_%s.gml" % (typeName, bboxLabel)
intGmlFilepath = os.path.join(outputDir, intGmlFilename)
out = open(intGmlFilepath, 'w')
out.write(gml.read())
out.close()
# Parse GML to get list of MUKEYs
gmlFile = open(intGmlFilepath, 'r')
ssurgoFeatureHandler = SSURGOFeatureHandler()
xml.sax.parse(gmlFile, ssurgoFeatureHandler)
gmlFile.close()
mukeys = ssurgoFeatureHandler.mukeys
if len(mukeys) < 1:
raise Exception("No SSURGO features returned from WFS query. SSURGO GML format may have changed.\nPlease contact the developer.")
# Get attributes (ksat, texture, %clay, %silt, and %sand) for all components in MUKEYS
attributes = getParentMatKsatTexturePercentClaySiltSandForComponentsInMUKEYs(mukeys)
# Compute weighted average of soil properties across all components in each map unit
avgAttributes = computeWeightedAverageKsatClaySandSilt(attributes)
# Convert GML to GeoJSON so that we can add fields easily (GDAL 1.10+ validates GML schema
# and won't let us add fields)
tmpGeoJSONFilename = convertGMLToGeoJSON(config, outputDir, intGmlFilepath, typeName)
tmpGeoJSONFilepath = os.path.join(outputDir, tmpGeoJSONFilename)
# Join map unit component-averaged soil properties to attribute table in GML file
# gmlFile = open(intGmlFilepath, 'r')
# joinedGmlStr = joinSSURGOAttributesToFeaturesByMUKEY(gmlFile, typeName, avgAttributes)
# gmlFile.close()
tmpGeoJSONFile = open(tmpGeoJSONFilepath, 'r')
geojson = json.load(tmpGeoJSONFile)
tmpGeoJSONFile.close()
joinSSURGOAttributesToFeaturesByMUKEY_GeoJSON(geojson, typeName, avgAttributes)
# Write Joined GeoJSON to a file
out = open(tmpGeoJSONFilepath, 'w')
json.dump(geojson, out)
out.close()
# Convert GeoJSON to shapefile
filename = os.path.splitext(intGmlFilename)[0]
shpFilename = convertGeoJSONToShapefile(config, outputDir, tmpGeoJSONFilepath, filename, t_srs=t_srs)
# Delete intermediate files
os.unlink(intGmlFilepath)
os.unlink(tmpGeoJSONFilepath)
outFiles.append(shpFilename)
# TODO: join tiled data if tileBbox
return outFiles
def getMapunitFeaturesForBoundingBox(config, outputDir, bbox, tileBbox=False, t_srs='EPSG:4326',
tileDivisor=SSURGO_BBOX_TILE_DIVISOR,
keepOriginals=False,
overwrite=True,
nprocesses=None):
""" Query USDA Soil Data Mart for SSURGO MapunitPolyExtended features with a given bounding box.
Features will be written to one or more shapefiles, one file for each bboxTile tile,
stored in the specified output directory. The filename will be returned as a string.
Will fetch SSURGO tabular data (see ssurgolib.attributequery.ATTRIBUTE_LIST for a list
of attributes) and join those data to the features in the final shapefiles(s).
@note Will silently exit if features already exist.
@param config onfigParser containing the section 'GDAL/OGR' and option 'PATH_OF_OGR2OGR'
@param outputDir String representing the absolute/relative path of the directory into which features should be written
@param bbox A dict containing keys: minX, minY, maxX, maxY, srs, where srs='EPSG:4326'
@param tileBoundingBox True if bounding box should be tiled if extent exceeds featurequery.MAX_SSURGO_EXTENT
@param t_srs String representing the spatial reference system of the output shapefiles, of the form 'EPSG:XXXX'
@param tileDivisor Float representing amount by which to divide tile slides.
@param keepOriginals Boolean, if True original feature layers will be retained (otherwise they will be deleted)
@param overwrite Boolean, if True any existing files will be overwritten
@param nprocesses Integer representing number of processes to use for fetching SSURGO tiles in parallel (used only if bounding box needs to be tiled).
if None, multiprocessing.cpu_count() will be used.
@return A list of strings representing the name of the shapefile(s) to which the mapunit features were saved.
@exception IOError if output directory is not a directory
@exception IOError if output directory is not writable
@exception Exception if tileDivisor is not a postive float > 0.0.
@exception Exception if bounding box area is greater than MAX_SSURGO_EXTENT
@exception Exception if no MUKEYs were returned
"""
if type(tileDivisor) != float or tileDivisor <= 0.0:
raise Exception("Tile divisor must be a float > 0.0.")
if not os.path.isdir(outputDir):
raise IOError(errno.ENOTDIR, "Output directory %s is not a directory" % (outputDir,))
if not os.access(outputDir, os.W_OK):
raise IOError(errno.EACCES, "Not allowed to write to output directory %s" % (outputDir,))
outputDir = os.path.abspath(outputDir)
typeName = 'MapunitPolyExtended'
if tileBbox:
bboxes = tileBoundingBox(bbox, MAX_SSURGO_EXTENT, t_srs, tileDivisor)
sys.stderr.write("Dividing bounding box %s into %d tiles\n" % (str(bbox), len(bboxes)))
else:
bboxArea = calculateBoundingBoxArea(bbox, t_srs)
if bboxArea > MAX_SSURGO_EXTENT:
raise Exception("Bounding box area %.2f sq. km is greater than %.2f sq. km. You must tile the bounding box." % (bboxArea/1000/1000, MAX_SSURGO_EXTENT/1000/1000,))
bboxes = [bbox]
numTiles = len(bboxes)
assert(numTiles >= 1)
outFiles = []
if numTiles == 1:
# No tiling, fetch SSURGO features for bbox in the current process
geojsonFilename = _getMapunitFeaturesForBoundingBoxTile(config, outputDir, bboxes[0], typeName, 1, numTiles)
outFiles.append(geojsonFilename)
else:
# Fetch SSURGO feature tiles in parallel
if nprocesses is None:
nprocesses = multiprocessing.cpu_count()
assert(type(nprocesses) == int)
assert(nprocesses > 0)
# Start my pool
pool = multiprocessing.Pool( nprocesses )
tasks = []
# Build task list
i = 1
for bboxTile in bboxes:
tasks.append( (config, outputDir, bboxTile, typeName, i, numTiles) )
i += 1
# Send tasks to pool (i.e. fetch SSURGO features for each tile in parallel)
results = [pool.apply_async(_getMapunitFeaturesForBoundingBoxTile, t) for t in tasks]
# Get resulting filenames for each tile
for result in results:
outFiles.append(result.get())
pool.close()
pool.join()
# Join tiled data if necessary
if len(outFiles) > 1:
sys.stderr.write('Merging tiled features to single shapefile...')
sys.stderr.flush()
shpFilepath = mergeFeatureLayers(config, outputDir, outFiles, typeName,
outFormat=OGR_SHAPEFILE_DRIVER_NAME,
keepOriginals=keepOriginals,
t_srs=t_srs,
overwrite=overwrite)
shpFilename = os.path.basename(shpFilepath)
sys.stderr.write('done\n')
else:
# Convert GeoJSON to shapefile
filepath = outFiles[0]
sys.stderr.write('Converting SSURGO features from GeoJSON to shapefile format...')
sys.stderr.flush()
shpFilename = convertGeoJSONToShapefile(config, outputDir, filepath, typeName, t_srs=t_srs)
os.unlink(filepath)
sys.stderr.write('done\n')
return shpFilename