# encoding: utf8
-from collections import namedtuple
import os, os.path
-import pkg_resources
import random
import re
import shutil
import whoosh.scoring
import whoosh.spelling
+from pokedex.util import namedtuple
+
from pokedex.db import connect
import pokedex.db.tables as tables
from pokedex.roomaji import romanize
+from pokedex.defaults import get_default_index_dir
__all__ = ['PokedexLookup']
LookupResult = namedtuple('LookupResult',
['object', 'indexed_name', 'name', 'language', 'iso3166', 'exact'])
+class UninitializedIndex(object):
+ class UninitializedIndexError(Exception):
+ pass
+
+ def __nonzero__(self):
+ """Dummy object should identify itself as False."""
+ return False
+
+ def __bool__(self):
+ """Python 3000 version of the above. Future-proofing rules!"""
+ return False
+
+ def __getattr__(self, *args, **kwargs):
+ raise self.UninitializedIndexError(
+ "The lookup index does not exist. Please use `pokedex setup` "
+ "or lookup.rebuild_index() to create it."
+ )
+
class LanguageWeighting(whoosh.scoring.Weighting):
"""A scoring class that forces otherwise-equal English results to come
before foreign results.
"""
+ def __init__(self, extra_weights={}, *args, **kwargs):
+ """`extra_weights` may be a dictionary of weights which will be
+ factored in.
+
+ Intended for use with spelling corrections, which come along with their
+ own weightings.
+ """
+ self.extra_weights = extra_weights
+ super(LanguageWeighting, self).__init__(*args, **kwargs)
+
def score(self, searcher, fieldnum, text, docnum, weight, QTF=1):
doc = searcher.stored_fields(docnum)
+
+ # Apply extra weight
+ weight = weight * self.extra_weights.get(text, 1.0)
+
if doc['language'] == None:
# English (well, "default"); leave it at 1
return weight
elif doc['language'] == u'Roomaji':
# Give Roomaji a little boost; it's most likely to be searched
- return weight * 0.95
+ return weight * 0.9
else:
# Everything else can drop down the totem pole
- return weight * 0.9
+ return weight * 0.8
class PokedexLookup(object):
INTERMEDIATE_LOOKUP_RESULTS = 25
MAX_LOOKUP_RESULTS = 10
+ # The speller only checks how much the input matches a word; there can be
+ # all manner of extra unmatched junk, and it won't affect the weighting.
+ # To compensate, greatly boost the weighting of matches at the beginning
+ # and end, so nearly-full-word-matches are much better
+ SPELLER_OPTIONS = dict(booststart=10.0, boostend=9.0)
+
# Dictionary of table name => table class.
# Need the table name so we can get the class from the table name after we
# retrieve something from the index
)
- def __init__(self, directory=None, session=None, recreate=False):
+ def __init__(self, directory=None, session=None):
"""Opens the whoosh index stored in the named directory. If the index
doesn't already exist, it will be created.
`pokedex` egg directory.
`session`
- If the index needs to be created, this database session will be
- used. Defaults to an attempt to connect to the default SQLite
- database installed by `pokedex setup`.
-
- `recreate`
- If set to True, the whoosh index will be created even if it already
- exists.
+ Used for creating the index and retrieving objects. Defaults to an
+ attempt to connect to the default SQLite database installed by
+ `pokedex setup`.
"""
# By the time this returns, self.index, self.speller, and self.session
# must be set
- # Defaults
- if not directory:
- directory = pkg_resources.resource_filename('pokedex',
- 'data/whoosh-index')
+ # If a directory was not given, use the default
+ if directory is None:
+ directory = get_default_index_dir()
+
+ self.directory = directory
if session:
self.session = session
self.session = connect()
# Attempt to open or create the index
- directory_exists = os.path.exists(directory)
- if directory_exists and not recreate:
- # Already exists; should be an index! Bam, done.
- try:
- self.index = whoosh.index.open_dir(directory, indexname='MAIN')
- spell_store = whoosh.filedb.filestore.FileStorage(directory)
- self.speller = whoosh.spelling.SpellChecker(spell_store)
- return
- except whoosh.index.EmptyIndexError as e:
- # Apparently not a real index. Fall out and create it
- pass
-
- # Delete and start over if we're going to bail anyway.
- if directory_exists and recreate:
- # Be safe and only delete if it looks like a whoosh index, i.e.,
- # everything starts with _
- if all(f[0] == '_' for f in os.listdir(directory)):
- shutil.rmtree(directory)
- directory_exists = False
-
- if not directory_exists:
- os.mkdir(directory)
-
-
- ### Create index
+ if not os.path.exists(directory) or not os.listdir(directory):
+ # Directory doesn't exist OR is empty; caller needs to use
+ # rebuild_index before doing anything. Provide a dummy object that
+ # complains when used
+ self.index = UninitializedIndex()
+ self.speller = UninitializedIndex()
+ return
+
+ # Otherwise, already exists; should be an index! Bam, done.
+ # Note that this will explode if the directory exists but doesn't
+ # contain an index; that's a feature
+ try:
+ self.index = whoosh.index.open_dir(directory, indexname='MAIN')
+ except whoosh.index.EmptyIndexError:
+ raise IOError(
+ "The index directory already contains files. "
+ "Please use a dedicated directory for the lookup index."
+ )
+
+ # Create speller, and done
+ spell_store = whoosh.filedb.filestore.FileStorage(directory)
+ self.speller = whoosh.spelling.SpellChecker(spell_store,
+ **self.SPELLER_OPTIONS)
+
+
+ def rebuild_index(self):
+ """Creates the index from scratch."""
+
schema = whoosh.fields.Schema(
name=whoosh.fields.ID(stored=True),
table=whoosh.fields.ID(stored=True),
display_name=whoosh.fields.STORED, # non-lowercased name
)
- self.index = whoosh.index.create_in(directory, schema=schema,
- indexname='MAIN')
+ if not os.path.exists(self.directory):
+ os.mkdir(self.directory)
+
+ self.index = whoosh.index.create_in(self.directory, schema=schema,
+ indexname='MAIN')
writer = self.index.writer()
# Index every name in all our tables of interest
- # speller_entries becomes a list of (word, score) tuples; the score is
- # 2 for English names, 1.5 for Roomaji, and 1 for everything else. I
- # think this biases the results in the direction most people expect,
- # especially when e.g. German names are very similar to English names
- speller_entries = []
+ speller_entries = set()
for cls in self.indexed_tables.values():
q = self.session.query(cls)
row_key = dict(table=unicode(cls.__tablename__),
row_id=unicode(row.id))
- def add(name, language, iso3166, score):
+ def add(name, language, iso3166):
normalized_name = self.normalize_name(name)
writer.add_document(
**row_key
)
- speller_entries.append((normalized_name, score))
+ speller_entries.add(normalized_name)
# Add the basic English name to the index
if cls == tables.Pokemon:
# Pokémon need their form name added
# XXX kinda kludgy
- add(row.full_name, None, u'us', 1)
+ add(row.full_name, None, u'us')
# If this is a default form, ALSO add the unadorned name,
# so 'Deoxys' alone will still do the right thing
if row.forme_name and not row.forme_base_pokemon_id:
- add(row.name, None, u'us', 1)
+ add(row.name, None, u'us')
else:
- add(row.name, None, u'us', 1)
+ add(row.name, None, u'us')
# Some things also have other languages' names
# XXX other language form names..?
continue
add(moonspeak, foreign_name.language.name,
- foreign_name.language.iso3166,
- 3)
+ foreign_name.language.iso3166)
# Add Roomaji too
if foreign_name.language.name == 'Japanese':
roomaji = romanize(foreign_name.name)
- add(roomaji, u'Roomaji', u'jp', 8)
+ add(roomaji, u'Roomaji', u'jp')
writer.commit()
# Construct and populate a spell-checker index. Quicker to do it all
# at once, as every call to add_* does a commit(), and those seem to be
# expensive
- self.speller = whoosh.spelling.SpellChecker(self.index.storage)
- self.speller.add_scored_words(speller_entries)
+ self.speller = whoosh.spelling.SpellChecker(self.index.storage, mingram=2,
+ **self.SPELLER_OPTIONS)
+ self.speller.add_words(speller_entries)
def normalize_name(self, name):
Returns None for a bogus name.
"""
+ # Table object
if hasattr(name, '__tablename__'):
return getattr(name, '__tablename__')
- elif name in self.indexed_tables:
- return name
- elif name + 's' in self.indexed_tables:
- return name + 's'
- else:
- # Bogus. Be nice and return dummy
- return None
+
+ # Table name
+ for table in self.indexed_tables.values():
+ if name in (table.__tablename__, table.__singlename__):
+ return table.__tablename__
+
+ # Bogus. Be nice and return dummy
+ return None
def _whoosh_records_to_results(self, records, exact=True):
"""Converts a list of whoosh's indexed records to LookupResult tuples
# Do different things depending what the query looks like
# Note: Term objects do an exact match, so we don't have to worry about
# a query parser tripping on weird characters in the input
+ try:
+ # Let Python try to convert to a number, so 0xff works
+ name_as_number = int(name, base=0)
+ except ValueError:
+ # Oh well
+ name_as_number = None
+
if '*' in name or '?' in name:
exact_only = True
query = whoosh.query.Wildcard(u'name', name)
- elif rx_is_number.match(name):
+ elif name_as_number is not None:
# Don't spell-check numbers!
exact_only = True
- query = whoosh.query.Term(u'row_id', name)
+ query = whoosh.query.Term(u'row_id', unicode(name_as_number))
else:
# Not an integer
query = whoosh.query.Term(u'name', name)
exact = False
results = []
- for suggestion in self.speller.suggest(
- name, self.INTERMEDIATE_LOOKUP_RESULTS):
-
- query = whoosh.query.Term('name', suggestion)
- results.extend(searcher.search(query))
+ fuzzy_query_parts = []
+ fuzzy_weights = {}
+ min_weight = [None]
+ for suggestion, _, weight in self.speller.suggestions_and_scores(name):
+ # Only allow the top 50% of scores; otherwise there will always
+ # be a lot of trailing junk
+ if min_weight[0] is None:
+ min_weight[0] = weight * 0.5
+ elif weight < min_weight[0]:
+ break
+
+ fuzzy_query_parts.append(whoosh.query.Term('name', suggestion))
+ fuzzy_weights[suggestion] = weight
+
+ if not fuzzy_query_parts:
+ # Nothing at all; don't try querying
+ return []
+
+ fuzzy_query = whoosh.query.Or(fuzzy_query_parts)
+ if type_term:
+ fuzzy_query = fuzzy_query & type_term
+
+ searcher.weighting = LanguageWeighting(extra_weights=fuzzy_weights)
+ results = searcher.search(fuzzy_query)
### Convert results to db objects
objects = self._whoosh_records_to_results(results, exact=exact)
projects / zzz-pokedex.git / blobdiff