uchardet/script/BuildLangModel.py
Jehan 3e5d37a6b5 BuildLangModel: process pages level per level.
I.e. horizontally or "breadth first" rather than vertical tree traversal.
This allows to make sure all the start pages in particular are searched,
when using max_page option.
2015-11-30 19:12:04 +01:00

447 lines
16 KiB
Python
Executable File

#!/bin/python3
# -*- coding: utf-8 -*-
# ##### BEGIN LICENSE BLOCK #####
# Version: MPL 1.1/GPL 2.0/LGPL 2.1
#
# The contents of this file are subject to the Mozilla Public License Version
# 1.1 (the "License"); you may not use this file except in compliance with
# the License. You may obtain a copy of the License at
# http://www.mozilla.org/MPL/
#
# Software distributed under the License is distributed on an "AS IS" basis,
# WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
# for the specific language governing rights and limitations under the
# License.
#
# The Original Code is Mozilla Universal charset detector code.
#
# The Initial Developer of the Original Code is
# Netscape Communications Corporation.
# Portions created by the Initial Developer are Copyright (C) 2001
# the Initial Developer. All Rights Reserved.
#
# Contributor(s):
# Jehan <jehan@girinstud.io>
#
# Alternatively, the contents of this file may be used under the terms of
# either the GNU General Public License Version 2 or later (the "GPL"), or
# the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
# in which case the provisions of the GPL or the LGPL are applicable instead
# of those above. If you wish to allow use of your version of this file only
# under the terms of either the GPL or the LGPL, and not to allow others to
# use your version of this file under the terms of the MPL, indicate your
# decision by deleting the provisions above and replace them with the notice
# and other provisions required by the GPL or the LGPL. If you do not delete
# the provisions above, a recipient may use your version of this file under
# the terms of any one of the MPL, the GPL or the LGPL.
#
# ##### END LICENSE BLOCK #####
# Third party modules.
import wikipedia
import importlib
import optparse
import datetime
import operator
import requests
import sys
import re
import os
# Custom modules.
import charsets.db
from charsets.codepoints import *
# Command line processing.
usage = 'Usage: {} <LANG-CODE>\n' \
'\nEx: `{} fr`'.format(__file__, __file__)
description = "Internal tool for uchardet to generate language data."
cmdline = optparse.OptionParser(usage, description = description)
cmdline.add_option('--max-page',
help = 'Maximum number of Wikipedia pages to parse (useful for debugging).',
action = 'store', type = 'int', dest = 'max_page', default = None)
cmdline.add_option('--max-depth',
help = 'Maximum depth when following links from start page (default: 2).',
action = 'store', type = 'int',
dest = 'max_depth', default = 2)
(options, langs) = cmdline.parse_args()
if len(langs) < 1:
print("Please select at least one language code.\n")
exit(1)
if len(langs) > 1:
print("This script is meant to generate data for one language at a time.\n")
exit(1)
lang = langs[0]
# Load the language data.
sys_path_backup = sys.path
current_dir = os.path.dirname(os.path.realpath(__file__))
sys.path = [current_dir + '/langs']
try:
lang = importlib.import_module(lang.lower())
except ImportError:
print('Unknown language code "{}": '
'file "langs/{}.py" does not exist.'.format(lang, lang.lower()))
exit(1)
sys.path = sys_path_backup
charsets = charsets.db.load(lang.charsets)
if not hasattr(lang, 'start_pages') or lang.start_pages is None or \
lang.start_pages == []:
# Let's start with the main page, assuming it should have links
# to relevant pages. In locale wikipedia, this page is usually redirected
# to a relevant page.
print("Warning: no `start_pages` set for '{}'. Using ['Main_Page'].\n"
" If you don't get good data, it is advised to set a "
"start_pages` variable yourself.".format(lang.code))
lang.start_pages = ['Main_Page']
if not hasattr(lang, 'wikipedia_code') or lang.wikipedia_code is None:
lang.wikipedia_code = lang.code
if not hasattr(lang, 'clean_wikipedia_content') or lang.clean_wikipedia_content is None:
lang.clean_wikipedia_content = None
if hasattr(lang, 'case_mapping'):
lang.case_mapping = bool(lang.case_mapping)
else:
lang.case_mapping = False
if not hasattr(lang, 'alphabet') or lang.alphabet is None:
lang.alphabet = None
if lang.alphabet is not None:
if lang.use_ascii:
lang.alphabet += [chr(l) for l in range(65, 91)] + [chr(l) for l in range(97, 123)]
if lang.case_mapping:
lang.alphabet = list(set([ l.lower() for l in lang.alphabet ]))
lang.alphabet = list(set(lang.alphabet))
# Starting processing.
wikipedia.set_lang(lang.wikipedia_code)
visited_pages = []
# The full list of letter characters.
# The key is the unicode codepoint,
# and the value is the occurrence count.
characters = {}
# Sequence of letters.
# The key is the couple (char1, char2) in unicode codepoint,
# the value is the occurrence count.
sequences = {}
prev_char = None
def process_text(text, clean_text, case_mapping):
global charsets
global characters
global sequences
global prev_char
if clean_text is not None:
content = clean_text(text)
# Clean multiple spaces. Newlines and such are normalized to spaces,
# since they have basically a similar role in the purpose of uchardet.
content = re.sub(r'\s+', ' ', content)
if case_mapping:
content = content.lower()
# In python 3, strings are UTF-8.
# Looping through them return expected characters.
for char in content:
is_letter = False
if ord(char) in characters:
characters[ord(char)] += 1
is_letter = True
else:
# We save the character if it is at least in one of the
# language encodings and its not a special character.
for charset in charsets:
# Does the character exist in the charset?
codepoint = char.encode(charset, 'ignore')
if codepoint == b'':
continue
# ord() is said to return the unicode codepoint.
# But it turns out it also gives the codepoint for other
# charsets if I turn the string to encoded bytes first.
# Not sure if that is a bug or expected.
codepoint = ord(codepoint)
if charsets[charset].charmap[codepoint] == LET:
characters[ord(char)] = 1
is_letter = True
break
if is_letter:
if prev_char is not None:
if (prev_char, ord(char)) in sequences:
sequences[(prev_char, ord(char))] += 1
else:
sequences[(prev_char, ord(char))] = 1
prev_char = ord(char)
else:
prev_char = None
def visit_pages(titles, depth, lang, logfd):
global visited_pages
global options
if len(titles) == 0:
return
next_titles = []
for title in titles:
if options.max_page is not None and \
len(visited_pages) > options.max_page:
return
if title in visited_pages:
continue
visited_pages += [title]
try:
page = wikipedia.page(title)
except (wikipedia.exceptions.PageError,
wikipedia.exceptions.DisambiguationError):
# Let's just discard a page when I get an exception.
continue
logfd.write("\n{} (revision {})".format(title, page.revision_id))
process_text(page.content,
lang.clean_wikipedia_content,
lang.case_mapping)
next_titles += page.links
if depth >= options.max_depth:
return
visit_pages (next_titles, depth + 1, lang, logfd)
build_log = current_dir + '/BuildLangModelLogs/LangFrenchModel.log'
logfd = open(build_log, 'w')
logfd.write('= Logs of language model for {} ({}) =\n'.format(lang.name, lang.code))
logfd.write('\n- Generated by {}'.format(os.path.basename(__file__)))
logfd.write('\n- Started: {}'.format(str(datetime.datetime.now())))
logfd.write('\n- Maximum depth: {}'.format(options.max_depth))
if options.max_page is not None:
logfd.write('\n- Max number of pages: {}'.format(options.max_page))
logfd.write('\n\n== Parsed pages ==\n')
try:
visit_pages(lang.start_pages, 0, lang, logfd)
except requests.exceptions.ConnectionError:
print('Error: connection to Wikipedia failed. Aborting\n')
exit(1)
logfd.write('\n\n== End of Parsed pages ==')
logfd.write('\n\n- Wikipedia parsing ended at: {}\n'.format(str(datetime.datetime.now())))
########### CHARACTERS ###########
# Character ratios.
ratios = {}
n_char = len(characters)
occurrences = sum(characters.values())
logfd.write("\n{} characters appeared {} times.\n".format(n_char, occurrences))
for char in characters:
ratios[char] = characters[char] / occurrences
#logfd.write("Character '{}' usage: {} ({} %)\n".format(chr(char),
# characters[char],
# ratios[char] * 100))
sorted_ratios = sorted(ratios.items(), key=operator.itemgetter(1),
reverse=True)
# Accumulated ratios of the frequent chars.
accumulated_ratios = 0
# If there is no alphabet defined, we just use the first 64 letters, which was
# the original default.
# If there is an alphabet, we make sure all the alphabet characters are in the
# frequent list, and we stop then. There may therefore be more or less than
# 64 frequent characters depending on the language.
if lang.alphabet is None:
freq_count = 64
else:
freq_count = 0
for order, (char, ratio) in enumerate(sorted_ratios):
if len(lang.alphabet) == 0:
break
if chr(char) in lang.alphabet:
lang.alphabet.remove(chr(char))
freq_count += 1
else:
if len(lang.alphabet) > 0:
print("Error: alphabet characters are absent from data collection"
"\n Please check the configuration or the data."
"\n Missing characters: {}".format(", ".join(lang.alphabet)))
exit(1)
logfd.write('\nFirst {} characters:'.format(freq_count))
for order, (char, ratio) in enumerate(sorted_ratios):
if order >= freq_count:
break
logfd.write("\n[{:2}] Char {}: {} %".format(order, chr(char), ratio * 100))
accumulated_ratios += ratio
logfd.write("\n\nThe first {} characters have an accumulated ratio of {}.\n".format(freq_count, accumulated_ratios))
with open(current_dir + '/header-template.cpp', 'r') as header_fd:
c_code = header_fd.read()
c_code += '\n/********* Language model for: {} *********/\n\n'.format(lang.name)
c_code += '/**\n * Generated by {}\n'.format(os.path.basename(__file__))
c_code += ' * On: {}\n'.format(str(datetime.datetime.now()))
c_code += ' **/\n'
c_code += \
"""
/* Character Mapping Table:
* ILL: illegal character.
* CTR: control character specific to the charset.
* RET: carriage/return.
* SYM: symbol (punctuation) that does not belong to word.
* NUM: 0 - 9.
*
* Other characters are ordered by probabilities
* (0 is the most common character in the language).
*
* Orders are generic to a language. So the codepoint with order X in
* CHARSET1 maps to the same character as the codepoint with the same
* order X in CHARSET2 for the same language.
* As such, it is possible to get missing order. For instance the
* ligature of 'o' and 'e' exists in ISO-8859-15 but not in ISO-8859-1
* even though they are both used for French. Same for the euro sign.
*/
"""
for charset in charsets:
charset_c = charset.replace('-', '_').title()
CTOM_str = 'static const unsigned char {}_CharToOrderMap[]'.format(charset_c)
CTOM_str += ' =\n{'
for line in range(0, 16):
CTOM_str += '\n '
for column in range(0, 16):
cp = line * 16 + column
cp_type = charsets[charset].charmap[cp]
if cp_type == ILL:
CTOM_str += 'ILL,'
elif cp_type == RET:
CTOM_str += 'RET,'
elif cp_type == CTR:
CTOM_str += 'CTR,'
elif cp_type == SYM:
CTOM_str += 'SYM,'
elif cp_type == NUM:
CTOM_str += 'NUM,'
else: # LET
uchar = bytes([cp]).decode(charset)
if lang.case_mapping and uchar.isupper():
uchar = uchar.lower()
for order, (char, ratio) in enumerate(sorted_ratios):
if char == ord(uchar):
CTOM_str += '{:3},'.format(order)
break
else:
CTOM_str += '{:3},'.format(n_char)
n_char += 1
CTOM_str += ' /* {:X}X */'.format(line)
CTOM_str += '\n};\n/*'
CTOM_str += 'X0 X1 X2 X3 X4 X5 X6 X7 X8 X9 XA XB XC XD XE XF'
CTOM_str += ' */\n\n'
c_code += CTOM_str
########### SEQUENCES ###########
ratios = {}
occurrences = sum(sequences.values())
ratio_512 = 0
ratio_1024 = 0
sorted_seqs = sorted(sequences.items(), key=operator.itemgetter(1),
reverse=True)
for order, ((c1, c2), count) in enumerate(sorted_seqs):
if order < 512:
ratio_512 += count
elif order < 1024:
ratio_1024 += count
else:
break
ratio_512 /= occurrences
ratio_1024 /= occurrences
logfd.write("\n{} sequences found.\n".format(len(sorted_seqs)))
c_code += """
/* Model Table:
* Total sequences: {}
* First 512 sequences: {}
* Next 512 sequences (512-1024): {}
* Rest: {}
* Negative sequences: TODO""".format(len(sorted_seqs),
ratio_512,
ratio_1024,
1 - ratio_512 - ratio_1024)
logfd.write("\nFirst 512 (typical positive ratio): {}".format(ratio_512))
logfd.write("\nNext 512 (512-1024): {}".format(ratio))
logfd.write("\nRest: {}".format(1 - ratio_512 - ratio_1024))
c_code += "\n */\n"
language_c = lang.name.replace('-', '_').title()
LM_str = 'static const PRUint8 {}LangModel[]'.format(language_c)
LM_str += ' =\n{'
for line in range(0, freq_count):
LM_str += '\n '
for column in range(0, freq_count):
# Let's not make too long lines.
if freq_count > 40 and column == int(freq_count / 2):
LM_str += '\n '
first_order = int(line)
second_order = column
if first_order < len(sorted_ratios) and second_order < len(sorted_ratios):
(first_char, _) = sorted_ratios[first_order]
(second_char, _) = sorted_ratios[second_order]
if (first_char, second_char) in sequences:
for order, (seq, _) in enumerate(sorted_seqs):
if seq == (first_char, second_char):
if order < 512:
LM_str += '3,'
elif order < 1024:
LM_str += '2,'
else:
LM_str += '1,'
break
else:
pass # impossible!
LM_str += '0,'
else:
LM_str += '0,'
else:
# It may indeed happen that we find less than 64 letters used for a
# given language.
LM_str += '0,'
LM_str += '\n};\n'
c_code += LM_str
for charset in charsets:
charset_c = charset.replace('-', '_').title()
SM_str = '\n\nconst SequenceModel {}{}Model ='.format(charset_c, language_c)
SM_str += '\n{\n '
SM_str += '{}_CharToOrderMap,\n {}LangModel,'.format(charset_c, language_c)
SM_str += '\n {},'.format(freq_count)
SM_str += '\n (float){},'.format(ratio_512)
SM_str += '\n {},'.format('PR_TRUE' if lang.use_ascii else 'PR_FALSE')
SM_str += '\n "{}"'.format(charset)
SM_str += '\n};'
c_code += SM_str
lang_model_file = current_dir + '/../src/LangModels/LangFrenchModel.cpp'
with open(lang_model_file, 'w') as cpp_fd:
cpp_fd.write(c_code)
logfd.write('\n\n- Processing end: {}\n'.format(str(datetime.datetime.now())))
logfd.close()
print("The following language model file has been generated: {}"
"\nThe build log is available in: {}"
"\nTest them and commit them.".format(lang_model_file, build_log))