def download(self):
params = self._getParams()
log.debug("params = %s" % (params,))
endpoint = params.get('ENDPOINT')
args = {}
args['identifier'] = params['LAYER']
args['bbox'] = tuple(params.get('BBOX').split(','))
args['format'] = params['FORMAT']
args['crs'] = params['CRS']
if (params.get('SINGLE_TIME',"").upper() == 'TRUE'):
args['time'] = [params.get('TIME')]
else:
args['time'] = [params.get('TIME'), params.get('TIME_END')]
wcs, layers = self._getWCSObj(endpoint)
log.debug("wcs.url = %s" % (wcs.url,))
assert args['identifier'] in layers
log.debug("args = %s" % (args,))
oldProxy = proxyFix(endpoint)
try:
output = wcs.getCoverage(**args)
except Exception, e:
log.exception("Exception occurred")
raise
def _getWCSMetadata(self, wcs, layer):
oldProxy = proxyFix(wcs.url)
try:
layerMetadata = wcs[layer]
bboxLimits = ','.join([str(x) for x in layerMetadata.boundingBoxWGS84])
timepositions = layerMetadata.timepositions
supportedFormats = layerMetadata.supportedFormats
supportedCRS = layerMetadata.supportedCRS
finally:
resetProxy(oldProxy)
return layerMetadata, bboxLimits, timepositions, supportedFormats, supportedCRS
def _getWcsData(params):
"""Performs WCS retrieval for a set of parameters.
@param params: parameters to use in WCS r equest
@return tuple (WCS response data, content header information)
"""
params = _getParams(params)
log.debug("params = %s" % (params,))
endpoint = params.get("ENDPOINT")
# Set OWSlib WCS parameters.
args = {}
layerId = params["LAYERS"].partition(",")[0]
args["identifier"] = layerId
# Get the bounding box values (W, S, E, N).
args["bbox"] = tuple(params.get("BBOX").split(","))
args["format"] = params["FORMAT"]
args["crs"] = params["CRS"]
args["time"] = params.get("TIME")
wcs, layers = _getWCSObj(endpoint)
log.debug("wcs.url = %s" % (wcs.url,))
if layerId not in layers:
raise Exception("Layer %s is not available for WCS download" % layerId)
# Find the dimension names for the layer, and if there are any request parameters with the same
# name as a dimension, use them as a GetCoverage argument.
layer = [x for x in wcs.items() if x[0] == layerId][0][1]
for dimensionName in [a.name.upper() for a in layer.axisDescriptions]:
log.debug("Checking for value for dimension %s" % dimensionName)
if dimensionName in params:
args[dimensionName] = params[dimensionName]
log.debug("Found value %s" % params[dimensionName])
log.debug("args = %s" % (args,))
# Perform the GetCoverage request.
oldProxy = proxyFix(endpoint)
try:
output = wcs.getCoverage(**args)
except Exception, e:
log.exception("Exception occurred")
raise
def _getWCSObj(self, endpoint):
oldProxy = proxyFix(endpoint)
try:
log.debug("wcs endpoint = %s" % (endpoint,))
getCapabilitiesEndpoint = parseEndpointString(endpoint,
{'Service':'WCS', 'Request':'GetCapabilities'})
log.debug("wcs endpoint = %s" % (getCapabilitiesEndpoint,))
#requires OWSLib with cookie support
wcs=WebCoverageService(getCapabilitiesEndpoint, version='1.0.0',cookies= request.headers.get('Cookie', ''))
layers = [x[0] for x in wcs.items()]
finally:
resetProxy(oldProxy)
return wcs, layers
def _getWCSObj(endpoint):
"""Contructs a WCS object for an endpoint.
@param endpoint: endpoint URL
@return WCS object
"""
oldProxy = proxyFix(endpoint)
try:
log.debug("wcs endpoint = %s" % (endpoint,))
getCapabilitiesEndpoint = parseEndpointString(endpoint, {"Service": "WCS", "Request": "GetCapabilities"})
log.debug("wcs endpoint = %s" % (getCapabilitiesEndpoint,))
# requires OWSLib with cookie support
wcs = WebCoverageService(getCapabilitiesEndpoint, version="1.0.0", cookies=request.headers.get("Cookie", ""))
layers = [x[0] for x in wcs.items()]
finally:
resetProxy(oldProxy)
return wcs, layers