# =================================================================
#
# Authors: Tom Kralidis <tomkralidis@gmail.com>
#
# Copyright (c) 2018 Tom Kralidis
#
# Permission is hereby granted, free of charge, to any person
# obtaining a copy of this software and associated documentation
# files (the "Software"), to deal in the Software without
# restriction, including without limitation the rights to use,
# copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the
# Software is furnished to do so, subject to the following
# conditions:
#
# The above copyright notice and this permission notice shall be
# included in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
# OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
# HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
# WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
# OTHER DEALINGS IN THE SOFTWARE.
#
# =================================================================
from collections import OrderedDict
import csv
import itertools
import logging
from pygeoapi.provider.base import (BaseProvider, ProviderQueryError,
ProviderItemNotFoundError)
LOGGER = logging.getLogger(__name__)
[docs]class CSVProvider(BaseProvider):
"""CSV provider"""
def __init__(self, provider_def):
"""
Initialize object
:param provider_def: provider definition
:returns: pygeoapi.provider.csv_.CSVProvider
"""
BaseProvider.__init__(self, provider_def)
self.geometry_x = provider_def['geometry']['x_field']
self.geometry_y = provider_def['geometry']['y_field']
self.fields = self.get_fields()
[docs] def get_fields(self):
"""
Get provider field information (names, types)
:returns: dict of fields
"""
LOGGER.debug('Treating all columns as string types')
with open(self.data) as ff:
LOGGER.debug('Serializing DictReader')
data_ = csv.DictReader(ff)
fields = {}
for f in data_.fieldnames:
fields[f] = 'string'
return fields
[docs] def _load(self, startindex=0, limit=10, resulttype='results',
identifier=None, bbox=[], datetime_=None, properties=[],
select_properties=[], skip_geometry=False):
"""
Load CSV data
:param startindex: starting record to return (default 0)
:param limit: number of records to return (default 10)
:param datetime_: temporal (datestamp or extent)
:param resulttype: return results or hit limit (default results)
:param properties: list of tuples (name, value)
:param select_properties: list of property names
:param skip_geometry: bool of whether to skip geometry (default False)
:returns: dict of GeoJSON FeatureCollection
"""
found = False
result = None
feature_collection = {
'type': 'FeatureCollection',
'features': []
}
with open(self.data) as ff:
LOGGER.debug('Serializing DictReader')
data_ = csv.DictReader(ff)
if resulttype == 'hits':
LOGGER.debug('Returning hits only')
feature_collection['numberMatched'] = len(list(data_))
return feature_collection
LOGGER.debug('Slicing CSV rows')
for row in itertools.islice(data_, startindex, startindex+limit):
feature = {'type': 'Feature'}
feature['id'] = row.pop(self.id_field)
if not skip_geometry:
feature['geometry'] = {
'type': 'Point',
'coordinates': [
float(row.pop(self.geometry_x)),
float(row.pop(self.geometry_y))
]
}
else:
feature['geometry'] = None
if self.properties or select_properties:
feature['properties'] = OrderedDict()
for p in set(self.properties) | set(select_properties):
try:
feature['properties'][p] = row[p]
except KeyError as err:
LOGGER.error(err)
raise ProviderQueryError()
else:
feature['properties'] = row
if identifier is not None and feature['id'] == identifier:
found = True
result = feature
feature_collection['features'].append(feature)
feature_collection['numberMatched'] = \
len(feature_collection['features'])
if identifier is not None and not found:
return None
elif identifier is not None and found:
return result
feature_collection['numberReturned'] = len(
feature_collection['features'])
return feature_collection
[docs] def query(self, startindex=0, limit=10, resulttype='results',
bbox=[], datetime_=None, properties=[], sortby=[],
select_properties=[], skip_geometry=False):
"""
CSV query
:param startindex: starting record to return (default 0)
:param limit: number of records to return (default 10)
:param resulttype: return results or hit limit (default results)
:param bbox: bounding box [minx,miny,maxx,maxy]
:param datetime_: temporal (datestamp or extent)
:param properties: list of tuples (name, value)
:param sortby: list of dicts (property, order)
:param select_properties: list of property names
:param skip_geometry: bool of whether to skip geometry (default False)
:returns: dict of GeoJSON FeatureCollection
"""
return self._load(startindex, limit, resulttype,
select_properties=select_properties,
skip_geometry=skip_geometry)
[docs] def get(self, identifier):
"""
query CSV id
:param identifier: feature id
:returns: dict of single GeoJSON feature
"""
item = self._load(identifier=identifier)
if item:
return item
else:
err = 'item {} not found'.format(identifier)
LOGGER.error(err)
raise ProviderItemNotFoundError(err)
def __repr__(self):
return '<CSVProvider> {}'.format(self.data)