class CertificateSearch(object):
""" Getting information about certificates issued by Ofgem requires accessing their webform.
This class provides a simple way of doing that.
Class that queries ofgem for certificate data. If it succeeds then
There are 2 generator methods that allow iterating through the returned data,
- each call to :func:`stations()` will return a list of :class:`Certificates` objects related to a single station.
- each call to :func:`certificates()` will return a single :class:`Certificates` object.
.. code::
>>> from pywind.ofgem.CertificateSearch import CertificateSearch
>>> ocs = CertificateSearch()
>>> ocs.start()
True
>>> ocs.set_period(201601)
True
>>> ocs.get_data()
True
>>> len(ocs)
4898
"""
START_URL = 'ReportViewer.aspx?ReportPath=/DatawarehouseReports/' + \
'CertificatesExternalPublicDataWarehouse&ReportVisibility=1&ReportCategory=2'
NSMAP = {'a': 'CertificatesExternalPublicDataWarehouse'}
def __init__(self, filename=None):
self.has_data = False
self.form = None
self.certificate_records = []
self.station_records = {}
if filename is not None:
self.parse_filename(filename)
else:
self.form = OfgemForm(self.START_URL)
def __len__(self):
return len(self.certificate_records)
def start(self):
""" Retrieve the form from Ofgem website so we can start updating it.
:returns: True or False
:rtype: bool
"""
if self.form is not None:
return self.form.get()
return True
def set_period(self, yearmonth):
""" Set the year and month for certificates.
:param yearmonth: Numeric period in YYYYMM format
:returns: True or False
:rtype: bool
"""
if not isinstance(yearmonth, int):
yearmonth = int(yearmonth)
year = int(yearmonth / 100)
if self._set_year(year) is False:
return False
return self._set_month(yearmonth % year)
def set_start_month(self, month):
""" Set the start month for certificates
:param month: Numeric month number
:rtype: bool
"""
return self.form.set_value("output period \"month from\"", MONTHS[month - 1])
def set_finish_month(self, month):
""" Set the finish month for certificates
:param month: Numeric month number
:rtype: bool
"""
return self.form.set_value("output period \"month to\"", MONTHS[month - 1])
def set_start_year(self, year):
""" Set the start year for certificates
:param year: Numeric year to be set
:rtype: bool
"""
return self.form.set_value("output period \"year from\"", str(year))
def set_finish_year(self, year):
""" Set the finish year for certificates
:param year: Numeric year to be set
:rtype: bool
"""
return self.form.set_value("output period \"year to\"", str(year))
def filter_technology(self, what):
""" Filter certificates by technology group """
return self.form.set_value('technology group', what)
def filter_generation_type(self, what):
""" Filter certificates by generation type """
return self.form.set_value('generation type', what)
def filter_scheme(self, what):
""" Filter certificates by scheme
:param what: Scheme abbreviation [REGO, RO]
:rtype: bool
"""
return self.form.set_value('scheme', what.upper())
def filter_generator_id(self, acc_no):
""" Filter certificates by generator id (accreditation number).
.. note::
Values supplied are upper cased automatically.
:param acc_no: Accreditation/Generation number
:rtype: bool
"""
return self.form.set_value('accreditation no', acc_no.upper())
def get_data(self):
""" Submit the form, get the results and parse them into :class:`Certificate` objects
:rtype: bool
"""
self.certificate_records = []
self.station_records = {}
if not self.form.submit():
return False
try:
xml = etree.fromstring(self.form.raw_data)
except XMLSyntaxError:
print("Invalid XML returned from Ofgem server.")
return False
for node in xml.xpath('.//a:Detail', namespaces=self.NSMAP):
cert = Certificates(node)
self.certificate_records.append(cert)
self.station_records.setdefault(cert.name, []).append(cert)
self.has_data = len(self.certificate_records) > 0
return self.has_data
def save_original(self, filename):
""" Save the downloaded certificate data into the filename provided.
:param filename: Filename to save the file to.
:rtype: bool
"""
return self.form.save_original(filename)
# Generators to access data
def rows(self):
""" Generator function that returns a station each time it is called.
:returns: A function that returns a dict containing information on one station.
:rtype: generator
"""
for cert in self.certificate_records:
yield {'CertificateRecord': cert.as_row()}
def certificates(self):
""" Generator that returns :class:`Certificates` objects.
:returns: Certificates objects
:rtype: Certificates
"""
for cert in self.certificate_records:
yield cert
def stations(self):
""" Generator that returns a Return a list of stations related to the certificates """
for stat in sorted(self.station_records):
yield self.station_records[stat]
def parse_filename(self, filename):
"""Parse an Ofgem generated file of certificates. This parses downloaded Ofgem files.
:param filename: The filename to be parsed
:returns: True or False
:rtype: bool
"""
with open(filename, 'r') as xfh:
data = xfh.read()
xml = etree.fromstring(data)
for node in xml.xpath('.//a:Detail', namespaces=self.NSMAP):
cert = Certificates(node)
self.certificate_records.append(cert)
self.station_records.setdefault(cert.name, []).append(cert)
return len(self.certificate_records) > 0
# Internal functions
def _set_year(self, year):
""" Set both the start and finish year for certificates.
:param year: Numeric year to set
:rtype: bool
"""
if self.set_start_year(year) is False:
return False
return self.set_finish_year(year)
def _set_month(self, month):
""" Set both the start and finish months for certificates
:param month: Numeric month number
:returns: True or False
:rtype: bool
"""
if self.set_start_month(month) is False:
return False
return self.set_finish_month(month)
class StationSearch(object):
""" Performing a station search using the Ofgem website takes a while due to the 3.5M initial file and the
2M replies that are sent. Parsing these takes time, so patience is needed.
.. code::
>>> from pywind.ofgem.StationSearch import StationSearch
>>> oss = StationSearch()
>>> oss.start()
True
>>> oss.filter_name('griffin')
True
>>> oss.get_data()
True
>>> len(oss)
4
"""
START_URL = 'ReportViewer.aspx?ReportPath=/Renewables/Accreditation/' + \
'AccreditedStationsExternalPublic&ReportVisibility=1&ReportCategory=1'
def __init__(self):
self.form = OfgemForm(self.START_URL)
self.stations = []
def __len__(self):
""" len(...) returns the number of stations available. """
return len(self.stations)
def __getitem__(self, item):
""" Get a station by name. """
if 0 >= item < len(self.stations):
return self.stations[item]
def start(self):
""" Retrieve the form from Ofgem website so we can start updating it.
"""
if self.form is not None:
self.form.get()
def get_data(self):
""" Get data from form.
:rtype: bool
"""
if not self.form.submit():
return False
parser = XMLParser(huge_tree=True)
doc = etree.fromstring(self.form.raw_data, parser=parser)
# There are a few stations with multiple generator id's, separated by '\n' so
# capture them and add each as a separate entry.
for detail in doc.xpath("//*[local-name()='Detail']"):
stt = Station(detail)
if '\n' in stt.generator_id:
ids = [x.strip() for x in stt.generator_id.split('\n')]
stt.generator_id = ids[0]
for _id in ids[1:]:
_st = copy.copy(stt)
_st.generator_id = _id
self.stations.append(_st)
self.stations.append(stt)
return len(self.stations) > 0
def filter_technology(self, what):
""" Filter stations based on technology.
:rtype: bool
"""
return self.form.set_value("technology", what)
def filter_scheme(self, scheme):
""" Filter stations based on scheme they are members of.
:rtype: bool
"""
return self.form.set_value("scheme", scheme.upper())
def filter_name(self, name):
""" Filter stations based on name. The search will return all stations containing the supplied name.
:param name: The name to filter for
:rtype: bool
"""
return self.form.set_value("generating station search", name)
def filter_generator_id(self, accno):
""" Filter stations based on generator id.
:rtype: bool
"""
return self.form.set_value("accreditation search", accno)
def filter_organisation(self, org_name):
"""
Filter stations based on generator id.
:param org_name: Organisation name to filter
:rtype: bool
"""
return self.form.set_value("organisation search", org_name)
def save_original(self, filename):
""" Save the downloaded station data into the filename provided.
:param filename: Filename to save the file to.
:rtype: bool
"""
return self.form.save_original(filename)
def rows(self):
""" Generator to return dicts of station information.
:returns: Dict of station information
:rtype: dict
"""
for station in self.stations:
yield {'Station': station.as_row()}