# encoding: utf8
+import os, os.path
+import random
import re
+import shutil
+import unicodedata
from sqlalchemy.sql import func
import whoosh
+import whoosh.filedb.filestore
+import whoosh.filedb.fileindex
+import whoosh.index
from whoosh.qparser import QueryParser
+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']
+
+
+rx_is_number = re.compile('^\d+$')
+
+LookupResult = namedtuple('LookupResult',
+ ['object', 'indexed_name', 'name', 'language', 'iso3166', 'exact'])
+
+class UninitializedIndex(object):
+ class UninitializedIndexError(Exception):
+ pass
-# 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
-indexed_tables = {}
-for cls in [
- tables.Pokemon,
- ]:
- indexed_tables[cls.__tablename__] = cls
+ def __nonzero__(self):
+ """Dummy object should identify itself as False."""
+ return False
-index_bits = {}
-def get_index(session):
- """Returns (index, speller).
+ def __bool__(self):
+ """Python 3000 version of the above. Future-proofing rules!"""
+ return False
- Creates an index if one does not exist.
+ 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.
"""
- if index_bits:
- return index_bits['index'], index_bits['speller']
+ 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 * 0.9
+ else:
+ # Everything else can drop down the totem pole
+ return weight * 0.8
+
- store = whoosh.store.RamStorage()
- schema = whoosh.fields.Schema(
- name=whoosh.fields.ID(stored=True),
- spelling_name=whoosh.fields.ID(stored=True),
- table=whoosh.fields.STORED,
- row_id=whoosh.fields.STORED,
- language_id=whoosh.fields.STORED,
+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
+ indexed_tables = dict(
+ (cls.__tablename__, cls)
+ for cls in (
+ tables.Ability,
+ tables.Item,
+ tables.Location,
+ tables.Move,
+ tables.Nature,
+ tables.Pokemon,
+ tables.Type,
+ )
)
- index = whoosh.index.Index(store, schema=schema, create=True)
- writer = index.writer()
- # Index every name in all our tables of interest
- for cls in indexed_tables.values():
- q = session.query(cls)
+ 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.
- # Only index base Pokémon formes
- if hasattr(cls, 'forme_base_pokemon_id'):
- q = q.filter_by(forme_base_pokemon_id=None)
+ `directory`
+ Directory containing the index. Defaults to a location within the
+ `pokedex` egg directory.
- for row in q.yield_per(5):
- name = row.name.lower()
- spelling_name = re.sub('[^a-z]', '', name)
- writer.add_document(name=name,
- spelling_name=spelling_name,
- table=cls.__tablename__,
- row_id=row.id)
+ `session`
+ Used for creating the index and retrieving objects. Defaults to an
+ attempt to connect to the default SQLite database installed by
+ `pokedex setup`.
+ """
- writer.commit()
+ # By the time this returns, self.index, self.speller, and self.session
+ # must be set
- ### Construct a spell-checker index
- speller = whoosh.spelling.SpellChecker(index.storage)
+ # If a directory was not given, use the default
+ if directory is None:
+ directory = get_default_index_dir()
- # Can't use speller.add_field because it tries to intuit a frequency, and
- # names are in an ID field, which seems to be immune to frequency.
- # Not hard to add everything ourselves, though
- reader = index.doc_reader()
- speller.add_words([ _['spelling_name'] for _ in reader ])
- reader.close()
+ self.directory = directory
- index_bits['index'] = index
- index_bits['speller'] = speller
- index_bits['store'] = store
- return index_bits['index'], index_bits['speller']
+ if session:
+ self.session = session
+ else:
+ self.session = connect()
-def lookup(session, name, exact_only=False):
- """Attempts to find some sort of object, given a database session and name.
+ # Attempt to open or create the 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
- Returns (objects, exact) where `objects` is a list of database objects, and
- `exact` is True iff the given name matched the returned objects exactly.
+ # 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."
+ )
- This function ONLY does fuzzy matching if there are no exact matches.
+ # Create speller, and done
+ spell_store = whoosh.filedb.filestore.FileStorage(directory)
+ self.speller = whoosh.spelling.SpellChecker(spell_store,
+ **self.SPELLER_OPTIONS)
- Formes are not returned; "Shaymin" will return only grass Shaymin.
- Currently recognizes:
- - Pokémon names: "Eevee"
- """
+ def rebuild_index(self):
+ """Creates the index from scratch."""
- exact = True
-
- # Alas! We have to make three attempts to find anything with this index.
- # First: Try an exact match for a name in the index.
- # Second: Try an exact match for a stripped-down name in the index.
- # Third: Get spelling suggestions.
- # The spelling module apparently only indexes *words* -- that is, [a-z]+.
- # So we have a separate field that contains the same name, stripped down to
- # just [a-z]+.
- # Unfortunately, exact matches aren't returned as spelling suggestions, so
- # we also have to do a regular index match against this separate field.
- # Otherwise, 'nidoran' will never match anything
- index, speller = get_index(session)
-
- # Look for exact name
- parser = QueryParser('name', schema=index.schema)
- results = index.find(name.lower(), parser=parser)
-
- if not exact_only:
- # Look for a match with a reduced a-z name
- if not results:
- parser = QueryParser('spelling_name', schema=index.schema)
- results = index.find(name.lower(), parser=parser)
-
- # Look for some fuzzy matches
- if not results:
- results = []
+ schema = whoosh.fields.Schema(
+ name=whoosh.fields.ID(stored=True),
+ table=whoosh.fields.ID(stored=True),
+ row_id=whoosh.fields.ID(stored=True),
+ language=whoosh.fields.STORED,
+ iso3166=whoosh.fields.STORED,
+ display_name=whoosh.fields.STORED, # non-lowercased name
+ )
+
+ 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 = set()
+ for cls in self.indexed_tables.values():
+ q = self.session.query(cls)
+
+ for row in q.yield_per(5):
+ row_key = dict(table=unicode(cls.__tablename__),
+ row_id=unicode(row.id))
+
+ def add(name, language, iso3166):
+ normalized_name = self.normalize_name(name)
+
+ writer.add_document(
+ name=normalized_name, display_name=name,
+ language=language, iso3166=iso3166,
+ **row_key
+ )
+
+ 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')
+
+ # 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')
+ else:
+ add(row.name, None, u'us')
+
+ # Some things also have other languages' names
+ # XXX other language form names..?
+ for foreign_name in getattr(row, 'foreign_names', []):
+ moonspeak = foreign_name.name
+ if row.name == moonspeak:
+ # Don't add the English name again as a different
+ # language; no point and it makes spell results
+ # confusing
+ continue
+
+ add(moonspeak, foreign_name.language.name,
+ foreign_name.language.iso3166)
+
+ # Add Roomaji too
+ if foreign_name.language.name == 'Japanese':
+ roomaji = romanize(foreign_name.name)
+ 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, mingram=2,
+ **self.SPELLER_OPTIONS)
+ self.speller.add_words(speller_entries)
+
+
+ def normalize_name(self, name):
+ """Strips irrelevant formatting junk from name input.
+
+ Specifically: everything is lowercased, and accents are removed.
+ """
+ # http://stackoverflow.com/questions/517923/what-is-the-best-way-to-remove-accents-in-a-python-unicode-string
+ # Makes sense to me. Decompose by Unicode rules, then remove combining
+ # characters, then recombine. I'm explicitly doing it this way instead
+ # of testing combining() because Korean characters apparently
+ # decompose! But the results are considered letters, not combining
+ # characters, so testing for Mn works well, and combining them again
+ # makes them look right.
+ nkfd_form = unicodedata.normalize('NFKD', unicode(name))
+ name = u"".join(c for c in nkfd_form
+ if unicodedata.category(c) != 'Mn')
+ name = unicodedata.normalize('NFC', name)
+
+ name = name.strip()
+ name = name.lower()
+
+ return name
+
+
+ def _apply_valid_types(self, name, valid_types):
+ """Combines the enforced `valid_types` with any from the search string
+ itself and updates the query.
+
+ For example, a name of 'a,b:foo' and valid_types of b,c will search for
+ only `b`s named "foo".
+
+ Returns `(name, merged_valid_types, term)`, where `name` has had any type
+ prefix stripped, `merged_valid_types` combines the original
+ `valid_types` with the type prefix, and `term` is a query term for
+ limited to just the allowed types. If there are no type restrictions
+ at all, `term` will be None.
+ """
+
+ # Remove any type prefix (pokemon:133) first
+ user_valid_types = []
+ if ':' in name:
+ prefix_chunk, name = name.split(':', 1)
+ name = name.strip()
+
+ prefixes = prefix_chunk.split(',')
+ user_valid_types = [_.strip() for _ in prefixes]
+
+ # Merge the valid types together. Only types that appear in BOTH lists
+ # may be used.
+ # As a special case, if the user asked for types that are explicitly
+ # forbidden, completely ignore what the user requested
+ combined_valid_types = []
+ if user_valid_types and valid_types:
+ combined_valid_types = list(
+ set(user_valid_types) & set(combined_valid_types)
+ )
+
+ if not combined_valid_types:
+ # No overlap! Just use the enforced ones
+ combined_valid_types = valid_types
+ else:
+ # One list or the other was blank, so just use the one that isn't
+ combined_valid_types = valid_types + user_valid_types
+
+ if not combined_valid_types:
+ # No restrictions
+ return name, [], None
+
+ # Construct the term
+ type_terms = []
+ final_valid_types = []
+ for valid_type in combined_valid_types:
+ table_name = self._parse_table_name(valid_type)
+
+ # Quietly ignore bogus valid_types; more likely to DTRT
+ if table_name:
+ final_valid_types.append(valid_type)
+ type_terms.append(whoosh.query.Term(u'table', table_name))
+
+ return name, final_valid_types, whoosh.query.Or(type_terms)
+
+
+ def _parse_table_name(self, name):
+ """Takes a singular table name, table name, or table object and returns
+ the table name.
+
+ Returns None for a bogus name.
+ """
+ # Table object
+ if hasattr(name, '__tablename__'):
+ return getattr(name, '__tablename__')
+
+ # 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
+ containing database objects.
+ """
+ # XXX this 'exact' thing is getting kinda leaky. would like a better
+ # way to handle it, since only lookup() cares about fuzzy results
+ seen = {}
+ results = []
+ for record in records:
+ # Skip dupes
+ seen_key = record['table'], record['row_id']
+ if seen_key in seen:
+ continue
+ seen[seen_key] = True
+
+ cls = self.indexed_tables[record['table']]
+ obj = self.session.query(cls).get(record['row_id'])
+
+ results.append(LookupResult(object=obj,
+ indexed_name=record['name'],
+ name=record['display_name'],
+ language=record['language'],
+ iso3166=record['iso3166'],
+ exact=exact))
+
+ return results
+
+
+ def lookup(self, input, valid_types=[], exact_only=False):
+ """Attempts to find some sort of object, given a name.
+
+ Returns a list of named (object, name, language, iso3166, exact)
+ tuples. `object` is a database object, `name` is the name under which
+ the object was found, `language` and `iso3166` are the name and country
+ code of the language in which the name was found, and `exact` is True
+ iff this was an
+ exact match.
+
+ This function currently ONLY does fuzzy matching if there are no exact
+ matches.
+
+ Formes are not returned unless requested; "Shaymin" will return only
+ grass Shaymin.
+
+ Extraneous whitespace is removed with extreme prejudice.
+
+ Recognizes:
+ - Names: "Eevee", "Surf", "Run Away", "Payapa Berry", etc.
+ - Foreign names: "Iibui", "Eivui"
+ - Fuzzy names in whatever language: "Evee", "Ibui"
+ - IDs: "133", "192", "250"
+ Also:
+ - Type restrictions. "type:psychic" will only return the type. This
+ is how to make ID lookup useful. Multiple type specs can be entered
+ with commas, as "move,item:1". If `valid_types` are provided, any
+ type prefix will be ignored.
+ - Alternate formes can be specified merely like "wash rotom".
+
+ `input`
+ Name of the thing to look for.
+
+ `valid_types`
+ A list of table objects or names, e.g., `['pokemon', 'moves']`. If
+ this is provided, only results in one of the given tables will be
+ returned.
+
+ `exact_only`
+ If True, only exact matches are returned. If set to False (the
+ default), and the provided `name` doesn't match anything exactly,
+ spelling correction will be attempted.
+ """
+
+ name = self.normalize_name(input)
+ exact = True
+ form = None
+
+ # Pop off any type prefix and merge with valid_types
+ name, merged_valid_types, type_term = \
+ self._apply_valid_types(name, valid_types)
+
+ # Random lookup
+ if name == 'random':
+ return self.random_lookup(valid_types=merged_valid_types)
+
+ # 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 name_as_number is not None:
+ # Don't spell-check numbers!
+ exact_only = True
+ query = whoosh.query.Term(u'row_id', unicode(name_as_number))
+ else:
+ # Not an integer
+ query = whoosh.query.Term(u'name', name)
+
+ if type_term:
+ query = query & type_term
+
+
+ ### Actual searching
+ searcher = self.index.searcher()
+ # XXX is this kosher? docs say search() takes a weighting arg, but it
+ # certainly does not
+ searcher.weighting = LanguageWeighting()
+ results = searcher.search(query,
+ limit=self.INTERMEDIATE_LOOKUP_RESULTS)
+
+ # Look for some fuzzy matches if necessary
+ if not exact_only and not results:
exact = False
+ results = []
+
+ 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)
+
+ # Only return up to 10 matches; beyond that, something is wrong. We
+ # strip out duplicate entries above, so it's remotely possible that we
+ # should have more than 10 here and lost a few. The speller returns 25
+ # to give us some padding, and should avoid that problem. Not a big
+ # deal if we lose the 25th-most-likely match anyway.
+ return objects[:self.MAX_LOOKUP_RESULTS]
+
+
+ def random_lookup(self, valid_types=[]):
+ """Returns a random lookup result from one of the provided
+ `valid_types`.
+ """
+
+ tables = []
+ for valid_type in valid_types:
+ table_name = self._parse_table_name(valid_type)
+ if table_name:
+ tables.append(self.indexed_tables[table_name])
+
+ if not tables:
+ # n.b.: It's possible we got a list of valid_types and none of them
+ # were valid, but this function is guaranteed to return
+ # *something*, so it politely selects from the entire index isntead
+ tables = self.indexed_tables.values()
+
+ # Rather than create an array of many hundred items and pick randomly
+ # from it, just pick a number up to the total number of potential
+ # items, then pick randomly from that, and partition the whole range
+ # into chunks. This also avoids the slight problem that the index
+ # contains more rows (for languages) for some items than others.
+ # XXX ought to cache this (in the index?) if possible
+ total = 0
+ partitions = []
+ for table in tables:
+ count = self.session.query(table).count()
+ total += count
+ partitions.append((table, count))
+
+ n = random.randint(1, total)
+ while n > partitions[0][1]:
+ n -= partitions[0][1]
+ partitions.pop(0)
+
+ return self.lookup(unicode(n), valid_types=[ partitions[0][0] ])
+
+ def prefix_lookup(self, prefix, valid_types=[]):
+ """Returns terms starting with the given exact prefix.
+
+ Type prefixes are recognized, but no other name munging is done.
+ """
+
+ # Pop off any type prefix and merge with valid_types
+ prefix, merged_valid_types, type_term = \
+ self._apply_valid_types(prefix, valid_types)
- for suggestion in speller.suggest(name, 3):
- results.extend( index.find(suggestion, parser=parser) )
+ query = whoosh.query.Prefix(u'name', self.normalize_name(prefix))
- # Convert results to db objects
- objects = []
- seen = {}
- for result in results:
- # Skip dupe results
- seen_key = result['table'], result['row_id']
- if seen_key in seen:
- continue
- seen[seen_key] = True
+ if type_term:
+ query = query & type_term
- cls = indexed_tables[result['table']]
- obj = session.query(cls).get(result['row_id'])
- objects.append(obj)
+ searcher = self.index.searcher()
+ searcher.weighting = LanguageWeighting()
+ results = searcher.search(query) # XXX , limit=self.MAX_LOOKUP_RESULTS)
- return objects, exact
+ return self._whoosh_records_to_results(results)
projects / zzz-pokedex.git / blobdiff