def current_data(**kwargs):
""" Get current data from the Feature table. """
# find the ID of the latest file
latest_file = session.query(OSMfile).order_by(
OSMfile.creation_date).all()[-1]
# get current features (features from the last file)
list_current = session.query(Feature).filter(and_(
Feature.all_tags[kwargs['fkey']] == kwargs['fvalue']),
Feature.file_id == latest_file.id,
Feature.osm_version >= kwargs['osm_version']).order_by(
Feature.osm_version).all()
return list_current
def count_inserts(**kwargs):
""" Counts the number of tag insertions. """
# get current data
list_current = current_data(**kwargs)
for i, current in enumerate(list_current):
# select all version of the feature
features = session.query(Feature).filter(
Feature.osm_id == current.osm_id).order_by(
Feature.osm_version).all()
# initialize counter
total = 0
if len(features) >= 2:
for i, feature in enumerate(features):
if i != 0:
previous = features[i - 1]
if feature.all_tags != previous.all_tags:
# go through all tags
for key in feature.all_tags:
if not previous.all_tags.has_key(key):
total += 1
# save results to the DB
save_result(kwargs['job_op_id'], current.osm_id, total)
def find_feature(osm_id, osm_version, osm_timestamp):
""" Fetches the existing feature. """
return session.query(Feature).filter(and_(
Feature.osm_id == osm_id,
Feature.osm_version == osm_version,
Feature.osm_timestamp == osm_timestamp)).first()
def count_geom_changes(**kwargs):
""" Counts the number of geometric changes. """
# get current data
list_current = current_data(**kwargs)
for i, current in enumerate(list_current):
if current.osm_version >= kwargs['osm_version']:
# select features based on the osm_id
features = session.query(Feature).filter(
Feature.osm_id == current.osm_id).order_by(
Feature.osm_version).all()
# initialize counter
total = 0
if len(features) >= 2:
for i, feature in enumerate(features):
if i != 0:
previous_geom = find_geom(features[i - 1])
current_geom = find_geom(feature)
if not previous_geom.almost_equals(current_geom):
total += 1
# save results to the DB
save_result(kwargs['job_op_id'], current.osm_id, total)
def time_boundary(**kwargs):
""" Sets the time boundary between up-to-date features and outdated
features. """
# find the ID of the latest file
latest_file = session.query(OSMfile).order_by(OSMfile.id).all()[-1]
# get current features (features from the last file)
features = session.query(Feature).filter(and_(
Feature.all_tags[kwargs['fkey']] == kwargs['fvalue']),
Feature.file_id == latest_file.id).order_by(
Feature.osm_timestamp).all()
# find the index of the median timestamp
idx = int(len(features) / 2)
return convert_timestamp(features[idx].osm_timestamp)
def count_updates(**kwargs):
""" Counts the number of modified tags or the number of modifications to a
certain tag of interest. """
# get current data
list_current = current_data(**kwargs)
# find TOI
try:
tag = kwargs['tag_of_interest']
except KeyError:
tag = None
for i, current in enumerate(list_current):
# select features based on the osm_id
features = session.query(Feature).filter(
Feature.osm_id == current.osm_id).order_by(
Feature.osm_version).all()
# initialize counter
total = 0
if len(features) >= 2:
for i, feature in enumerate(features):
if i != 0:
previous = features[i - 1]
# if no tag was specified
if not tag:
for key in feature.all_tags:
# go through all tags
if previous.all_tags.has_key(key) and \
feature.all_tags.has_key(key) and \
previous.all_tags[key] != feature.all_tags[key]:
total += 1
# if a tag was specified
else:
# check the specified tag
if previous.all_tags.has_key(tag) and \
feature.all_tags.has_key(tag) and \
previous.all_tags[tag] != feature.all_tags[tag]:
total += 1
# save results to the DB
save_result(kwargs['job_op_id'], current.osm_id, total)
def count_deletions(**kwargs):
""" Counts the number of deleted tags. """
# get current data
list_current = current_data(**kwargs)
# check if any specific tag was specified
try:
tag = kwargs['tag_of_interest']
except KeyError:
tag = None
for i, current in enumerate(list_current):
# select features based on the osm_id
features = session.query(Feature).filter(
Feature.osm_id == current.osm_id).order_by(
Feature.osm_version).all()
# initialize counter
total = 0
if len(features) >= 2:
for i, feature in enumerate(features):
if i != 0:
previous = features[i - 1]
# if no tag was specified
if tag == None:
# go through all tags
for key in previous.all_tags:
if previous.all_tags.has_key(key) == True and \
feature.all_tags.has_key(key) == False:
total += 1
# if a tag was specified
else:
# check the specified tag
if previous.all_tags.has_key(tag) == True and \
feature.all_tags.has_key(tag) == False:
total += 1
# save results to the DB
save_result(kwargs['job_op_id'], current.osm_id, total)
def save_result(job_operation_id, osm_id, value):
""" Save the result into an Hstore.
For more info visit: http://stackoverflow.com/questions/28331046/\
why-does-sqlalchemy-initialize-hstore-field-as-null """
# checks the existence of the job->operation combination
exists = session.query(Result).filter(
Result.job_operation_id == job_operation_id).first()
# saves new results
if not exists:
new_result = Result()
new_result.job_operation_id = job_operation_id
new_result.results[osm_id] = str(value)
session.add(new_result)
# updates existing results
else:
exists.results[osm_id] = str(value)
session.flush()
def find_file(date):
""" Fetches the existing file. """
return session.query(OSMfile).filter(OSMfile.creation_date == date).first()
def main(**kwargs):
# create a new job
job = Job(kwargs['new_job'])
for key in kwargs:
# find operations
if key[:3] == 'op_':
# check for an existing operation
existing_operation = session.query(Operation).filter(
Operation.func_name == key[3:]).first()
# define JobOperation parameters
job_oper = JobOperation(';'.join([str(kwargs[a]) for a in kwargs
if kwargs[a] != True]))
# define new operation
if not existing_operation:
job_oper.operation = Operation(key[3:])
# use existing operation
else:
job_oper.operation = existing_operation
# add job and operatios to DB
job.operations.append(job_oper)
session.add_all([job, job_oper])
session.flush()
for assoc in job.operations:
# ignore output function
if assoc.operation.func_name != 'geojson':
# initialize counter functions
if assoc.operation.func_name[:5] == 'count':
operation = getattr(operations.counters,
assoc.operation.func_name)
# initialize change functions
elif assoc.operation.func_name[:6] == 'change':
operation = getattr(operations.changes,
assoc.operation.func_name)
# initialize currency functions
elif assoc.operation.func_name[:8] == 'currency':
operation = getattr(operations.currency,
assoc.operation.func_name)
# initialize geometry functions
elif assoc.operation.func_name[:4] == 'geom':
operation = getattr(operations.geometry,
assoc.operation.func_name)
# test the existence of a tag of interest (TOI)
try:
operation(
job_op_id=assoc.id,
fkey=kwargs['fkey'],
fvalue=kwargs['fvalue'],
osm_version=kwargs['osm_version'],
tag_of_interest=kwargs['tag_of_interest'])
except KeyError:
operation(
job_op_id=assoc.id,
fkey=kwargs['fkey'],
fvalue=kwargs['fvalue'],
osm_version=kwargs['osm_version'])
session.flush()
# create a GeoJSON output file
if kwargs['op_geojson']:
create_GeoJSON(job, kwargs)
