X-Git-Url: http://git.veekun.com/zzz-pokedex.git/blobdiff_plain/4fe48baffb5156027c6d186308998412554a6906..6ff4ec1d39cbccc5a50c2ecc7124074d1dd15455:/pokedex/lookup.py diff --git a/pokedex/lookup.py b/pokedex/lookup.py index dcc3e7a..69eedc4 100644 --- a/pokedex/lookup.py +++ b/pokedex/lookup.py @@ -1,135 +1,423 @@ # encoding: utf8 +from collections import namedtuple +import os, os.path +import pkg_resources +import random import re +import shutil 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.db import connect import pokedex.db.tables as tables +from pokedex.roomaji import romanize + +__all__ = ['open_index', 'lookup', 'random_lookup'] + +INTERMEDIATE_LOOKUP_RESULTS = 25 +MAX_LOOKUP_RESULTS = 10 # 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.Ability, + tables.Item, + tables.Move, tables.Pokemon, + tables.Type, ]: indexed_tables[cls.__tablename__] = cls -index_bits = {} -def get_index(session): - """Returns (index, speller). +def open_index(directory=None, session=None, recreate=False): + """Opens the whoosh index stored in the named directory and returns (index, + speller). If the index doesn't already exist, it will be created. + + `directory` + Directory containing the index. Defaults to a location within the + `pokedex` egg directory. - Creates an index if one does not exist. + `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. """ - if index_bits: - return index_bits['index'], index_bits['speller'] + # Defaults + if not directory: + directory = pkg_resources.resource_filename('pokedex', + 'data/whoosh-index') + + if not session: + 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! + try: + index = whoosh.index.open_dir(directory, indexname='MAIN') + spell_store = whoosh.filedb.filestore.FileStorage(directory) + speller = whoosh.spelling.SpellChecker(spell_store) + return index, speller + except whoosh.index.EmptyIndexError as e: + # Apparently not a real index. Fall out of the if 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) + - store = whoosh.store.RamStorage() + ### Create index 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, + 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 + forme_name=whoosh.fields.ID, ) - index = whoosh.index.Index(store, schema=schema, create=True) + index = whoosh.index.create_in(directory, schema=schema, indexname='MAIN') writer = 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 = [] for cls in indexed_tables.values(): q = session.query(cls) - # Only index base Pokémon formes - if hasattr(cls, 'forme_base_pokemon_id'): - q = q.filter_by(forme_base_pokemon_id=None) - 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) + # XXX need to give forme_name a dummy value because I can't search + # for explicitly empty fields. boo. + row_key = dict(table=unicode(cls.__tablename__), + row_id=unicode(row.id), + forme_name=u'XXX') + + def add(name, language, iso3166, score): + writer.add_document(name=name.lower(), display_name=name, + language=language, + iso3166=iso3166, + **row_key) + speller_entries.append((name.lower(), score)) + + # If this is a form, mark it as such + if getattr(row, 'forme_base_pokemon_id', None): + row_key['forme_name'] = row.forme_name + + name = row.name + add(name, None, u'us', 1) + + # Pokemon also get other languages + for foreign_name in getattr(row, 'foreign_names', []): + moonspeak = foreign_name.name + if 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, + 3) + + # Add Roomaji too + if foreign_name.language.name == 'Japanese': + roomaji = romanize(foreign_name.name) + add(roomaji, u'Roomaji', u'jp', 8) writer.commit() - ### Construct a spell-checker index + # 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 speller = whoosh.spelling.SpellChecker(index.storage) + speller.add_scored_words(speller_entries) - # 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() + return index, speller - index_bits['index'] = index - index_bits['speller'] = speller - index_bits['store'] = store - return index_bits['index'], index_bits['speller'] -def lookup(session, name, exact_only=False): - """Attempts to find some sort of object, given a database session and name. +class LanguageWeighting(whoosh.scoring.Weighting): + """A scoring class that forces otherwise-equal English results to come + before foreign results. + """ - Returns (objects, exact) where `objects` is a list of database objects, and - `exact` is True iff the given name matched the returned objects exactly. + def score(self, searcher, fieldnum, text, docnum, weight, QTF=1): + doc = searcher.stored_fields(docnum) + if doc['language'] == None: + # English (well, "default"); leave it at 1 + return weight + elif doc['language'] == u'Roomaji': + # Give Roomaji a bit of a boost, as it's most likely to be searched + return weight * 0.95 + else: + # Everything else can drop down the totem pole + return weight * 0.9 - This function ONLY does fuzzy matching if there are no exact matches. +rx_is_number = re.compile('^\d+$') - Formes are not returned; "Shaymin" will return only grass Shaymin. +LookupResult = namedtuple('LookupResult', + ['object', 'name', 'language', 'iso3166', 'exact']) - Currently recognizes: - - Pokémon names: "Eevee" - """ +def _parse_table_name(name): + """Takes a singular table name, table name, or table object and returns the + table name. - exact = True + Returns None for a bogus name. + """ + if hasattr(name, '__tablename__'): + return getattr(name, '__tablename__') + elif name in indexed_tables: + return name + elif name + 's' in indexed_tables: + return name + 's' + else: + # Bogus. Be nice and return dummy + return None - # 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 = [] - exact = False - - for suggestion in speller.suggest(name, 3): - results.extend( index.find(suggestion, parser=parser) ) - - # Convert results to db objects - objects = [] +def _whoosh_records_to_results(records, session, 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 = {} - for result in results: - # Skip dupe results - seen_key = result['table'], result['row_id'] + 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 = indexed_tables[result['table']] - obj = session.query(cls).get(result['row_id']) - objects.append(obj) + cls = indexed_tables[record['table']] + obj = session.query(cls).get(record['row_id']) + + results.append(LookupResult(object=obj, + name=record['display_name'], + language=record['language'], + iso3166=record['iso3166'], + exact=exact)) + + return results + + +def lookup(input, valid_types=[], session=None, indices=None, exact_only=False): + """Attempts to find some sort of object, given a database session and 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. + + `session` + A database session to use for retrieving objects. As with get_index, + if this is not provided, a connection to the default database will be + attempted. + + `indices` + Tuple of index, speller as returned from `open_index()`. Defaults to + a call to `open_index()`. + + `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. + """ + + if not session: + session = connect() + + if indices: + index, speller = indices + else: + index, speller = open_index() + + name = unicode(input).strip().lower() + exact = True + form = None + + # Remove any type prefix (pokemon:133) before constructing a query + if ':' in name: + prefix_chunk, name = name.split(':', 1) + name = name.strip() + + if not valid_types: + # Only use types from the query string if none were explicitly + # provided + prefixes = prefix_chunk.split(',') + valid_types = [_.strip() for _ in prefixes] + + # Random lookup + if name == 'random': + return random_lookup(indices=(index, speller), + session=session, + valid_types=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 + if '*' in name or '?' in name: + exact_only = True + query = whoosh.query.Wildcard(u'name', name) + elif rx_is_number.match(name): + # Don't spell-check numbers! + exact_only = True + query = whoosh.query.Term(u'row_id', name) + else: + # Not an integer + query = whoosh.query.Term(u'name', name) \ + & whoosh.query.Term(u'forme_name', u'XXX') + + # If there's a space in the input, this might be a form + if ' ' in name: + form, formless_name = name.split(' ', 1) + form_query = whoosh.query.Term(u'name', formless_name) \ + & whoosh.query.Term(u'forme_name', form) + query = query | form_query + + ### Filter by type of object + type_terms = [] + for valid_type in valid_types: + table_name = _parse_table_name(valid_type) + type_terms.append(whoosh.query.Term(u'table', table_name)) + + if type_terms: + query = query & whoosh.query.Or(type_terms) + + + ### Actual searching + searcher = index.searcher() + searcher.weighting = LanguageWeighting() # XXX kosher? docs say search() + # takes a weighting kw but it + # certainly does not + results = searcher.search(query, limit=INTERMEDIATE_LOOKUP_RESULTS) + + # Look for some fuzzy matches if necessary + if not exact_only and not results: + exact = False + results = [] + + for suggestion in speller.suggest(name, INTERMEDIATE_LOOKUP_RESULTS): + query = whoosh.query.Term('name', suggestion) + results.extend(searcher.search(query)) + + ### Convert results to db objects + objects = _whoosh_records_to_results(results, session, 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[:MAX_LOOKUP_RESULTS] + + +def random_lookup(valid_types=[], session=None, indices=None): + """Takes similar arguments as `lookup()`, but returns a random lookup + result from one of the provided `valid_types`. + """ + + tables = [] + for valid_type in valid_types: + table_name = _parse_table_name(valid_type) + if table_name: + tables.append(indexed_tables[table_name]) + + if not tables: + tables = 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 + total = 0 + partitions = [] + for table in tables: + count = 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 lookup(unicode(n), valid_types=[ partitions[0][0] ], + indices=indices, session=session) + +def prefix_lookup(prefix, session=None, indices=None): + """Returns terms starting with the given exact prefix. + + No special magic is currently done with the name; type prefixes are not + recognized. + + `session` and `indices` are treated as with `lookup()`. + """ + + if not session: + session = connect() + + if indices: + index, speller = indices + else: + index, speller = open_index() + + query = whoosh.query.Prefix(u'name', prefix.lower()) + + searcher = index.searcher() + searcher.weighting = LanguageWeighting() + results = searcher.search(query) # XXX , limit=MAX_LOOKUP_RESULTS) - return objects, exact + return _whoosh_records_to_results(results, session)