"""
Collect codes of
`railway viaducts <http://www.railwaycodes.org.uk/tunnels/tunnels0.shtm>`_.
"""
import copy
import itertools
import os
import re
import urllib.parse
import pandas as pd
from pyhelpers.dir import cd, validate_input_data_dir
from pyhelpers.store import load_pickle, save_pickle
from pyhelpers.text import find_similar_str
from pyrcs.utils import cd_dat, get_catalogue, get_last_updated_date, homepage_url
[docs]class Viaducts:
"""
A class for collecting railway viaducts.
:param data_dir: name of data directory, defaults to ``None``
:type data_dir: str, None
:param update: whether to check on update and proceed to update the package data,
defaults to ``False``
:type update: bool
**Example**::
>>> from pyrcs.other_assets import Viaducts
>>> viaducts = Viaducts()
>>> print(viaducts.Name)
Railway viaducts
>>> print(viaducts.SourceURL)
http://www.railwaycodes.org.uk/viaducts/viaducts0.shtm
"""
def __init__(self, data_dir=None, update=False):
"""
Constructor method.
"""
self.Name = 'Railway viaducts'
self.Key = 'Viaducts'
self.LUDKey = 'Last updated date'
self.HomeURL = homepage_url()
self.SourceURL = urllib.parse.urljoin(self.HomeURL, '/viaducts/viaducts0.shtm')
self.Catalogue = \
get_catalogue(self.SourceURL, update=update, confirmation_required=False)
self.P1Key, self.P2Key, self.P3Key, self.P4Key, self.P5Key, self.P6Key = \
list(self.Catalogue.keys())[1:]
self.Date = get_last_updated_date(self.SourceURL, parsed=True, as_date_type=False)
self.DataDir = validate_input_data_dir(data_dir) if data_dir \
else cd_dat("other-assets", self.Key.lower())
self.CurrentDataDir = copy.copy(self.DataDir)
[docs] def cdd_viaducts(self, *sub_dir, **kwargs):
"""
Change directory to package data directory and sub-directories (and/or a file).
The directory for this module: ``"\\dat\\other-assets\\viaducts"``.
:param sub_dir: sub-directory or sub-directories (and/or a file)
:type sub_dir: str
:param kwargs: optional parameters of
`os.makedirs <https://docs.python.org/3/library/os.html#os.makedirs>`_,
e.g. ``mode=0o777``
:return: path to the backup data directory for ``Viaducts``
:rtype: str
:meta private:
"""
path = cd(self.DataDir, *sub_dir, mkdir=True, **kwargs)
return path
[docs] def collect_railway_viaducts_by_page(self, page_no, update=False, verbose=False):
"""
Collect data of railway viaducts for a given page number from source web page.
:param page_no: page number;
valid values include ``1``, ``2``, ``3``, ``4``, ``5``, and ``6``
:type page_no: int, str
:param update: whether to check on update and proceed to update the package data,
defaults to ``False``
:type update: bool
:param verbose: whether to print relevant information in console
as the function runs, defaults to ``False``
:type verbose: bool
:return: railway viaducts data of the given ``page_no`` and
date of when the data was last updated
:rtype: dict
**Example**::
>>> from pyrcs.other_assets import Viaducts
>>> viaducts = Viaducts()
>>> viaducts_1 = viaducts.collect_railway_viaducts_by_page(page_no=1)
>>> type(viaducts_1)
<class 'dict'>
>>> print(list(viaducts_1.keys()))
['Page 1 (A-C)', 'Last updated date']
"""
assert page_no in range(1, 7), \
"Valid \"page_no\" must be one of 1, 2, 3, 4, 5, and 6."
page_name = find_similar_str(str(page_no), list(self.Catalogue.keys()))
pickle_filename = re.sub(
r"[()]", "", re.sub(r"[ -]", "-", page_name)).lower() + ".pickle"
path_to_pickle = self.cdd_viaducts(pickle_filename)
if os.path.isfile(path_to_pickle) and not update:
page_railway_viaducts = load_pickle(path_to_pickle)
else:
url = self.Catalogue[page_name]
try:
last_updated_date = get_last_updated_date(url)
except Exception as e:
print("Failed to find the last updated date for viaducts data of "
"{}. {}".format(page_name, e))
last_updated_date = None
try:
header, viaducts_table = \
pd.read_html(url, na_values=[''], keep_default_na=False)
viaducts_table.columns = header.columns.to_list()
viaducts_table.fillna('', inplace=True)
except Exception as e:
print("Failed to collect viaducts data of {}. {}".format(page_name, e))
viaducts_table = None
page_railway_viaducts = {page_name: viaducts_table,
self.LUDKey: last_updated_date}
save_pickle(page_railway_viaducts, path_to_pickle, verbose=verbose)
return page_railway_viaducts
[docs] def fetch_railway_viaducts(self, update=False, pickle_it=False, data_dir=None,
verbose=False):
"""
Fetch data of railway viaducts from local backup.
:param update: whether to check on update and proceed to update the package data,
defaults to ``False``
:type update: bool
:param pickle_it: whether to replace the current package data
with newly collected data, defaults to ``False``
:type pickle_it: bool
:param data_dir: name of package data folder, defaults to ``None``
:type data_dir: str, None
:param verbose: whether to print relevant information in console
as the function runs, defaults to ``False``
:type verbose: bool
:return: railway viaducts data and date of when the data was last updated
:rtype: dict
**Example**::
>>> from pyrcs.other_assets import Viaducts
>>> viaducts = Viaducts()
>>> viaducts_data = viaducts.fetch_railway_viaducts()
>>> type(viaducts_data)
<class 'dict'>
>>> print(list(viaducts_data.keys()))
['Viaducts', 'Last updated date']
>>> viaducts_dat = viaducts_data['Viaducts']
>>> type(viaducts_dat)
<class 'dict'>
>>> print(list(viaducts_dat.keys()))
['Page 1 (A-C)',
'Page 2 (D-G)',
'Page 3 (H-K)',
'Page 4 (L-P)',
'Page 5 (Q-S)',
'Page 6 (T-Z)']
"""
verbose_ = False if data_dir or not verbose else True
codes = [self.collect_railway_viaducts_by_page(page_no, update, verbose=verbose_)
for page_no in range(1, 7)]
railways_viaducts_data = {
self.Key: {next(iter(x)): next(iter(x.values())) for x in codes},
self.LUDKey:
max(next(itertools.islice(iter(x.values()), 1, 2)) for x in codes)}
if pickle_it and data_dir:
self.CurrentDataDir = validate_input_data_dir(data_dir)
path_to_pickle = os.path.join(
self.CurrentDataDir, self.Key.lower().replace(" ", "-") + ".pickle")
save_pickle(railways_viaducts_data, path_to_pickle, verbose=verbose)
return railways_viaducts_data