# encoding: utf8
+import os, os.path
+import pkg_resources
import re
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.spelling
+from pokedex.db import connect
import pokedex.db.tables as tables
# Dictionary of table name => table class.
# 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).
-
- Creates an index if one does not exist.
+# Dictionary of extra keys to file types of objects under, e.g. Pokémon can
+# also be looked up purely by number
+extra_keys = {
+ tables.Move: [
+ lambda row: u"move %d" % row.id,
+ ],
+ tables.Pokemon: [
+ lambda row: unicode(row.id),
+ ],
+}
+
+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.
+
+ `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='pokedex')
+ speller = whoosh.index.open_dir(directory, indexname='spelling')
+ return index, speller
+ except whoosh.index.EmptyIndexError as e:
+ # Apparently not a real index. Fall out of the if and create it
+ pass
+
+ 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,
+ language=whoosh.fields.STORED,
)
- index = whoosh.index.Index(store, schema=schema, create=True)
+ index = whoosh.index.create_in(directory, schema=schema,
+ indexname='pokedex')
writer = index.writer()
# Index every name in all our tables of interest
+ speller_entries = []
for cls in indexed_tables.values():
q = session.query(cls)
q = q.filter_by(forme_base_pokemon_id=None)
for row in q.yield_per(5):
+ row_key = dict(table=cls.__tablename__, row_id=row.id)
+
+ # Spelling index only indexes strings of letters, alas, so we
+ # reduce every name to this to make the index work. However, exact
+ # matches are not returned, so e.g. 'nidoran' would neither match
+ # exactly nor fuzzy-match. Solution: add the spelling-munged name
+ # as a regular index row too.
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)
+ writer.add_document(name=name, **row_key)
+
+ speller_entries.append(name)
+
+ for extra_key_func in extra_keys.get(cls, []):
+ extra_key = extra_key_func(row)
+ writer.add_document(name=extra_key, **row_key)
writer.commit()
- ### Construct a spell-checker index
- speller = whoosh.spelling.SpellChecker(index.storage)
+ # 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, indexname='spelling')
+ speller.add_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):
+def lookup(name, session=None, exact_only=False):
"""Attempts to find some sort of object, given a database session and name.
Returns (objects, exact) where `objects` is a list of database objects, and
Currently recognizes:
- Pokémon names: "Eevee"
+
+ `name`
+ Name of the thing to look for.
+
+ `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.
+
+ `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()
+
+ index, speller = open_index()
+
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)
+ # Look for exact name. A Term object does an exact match, so we don't have
+ # to worry about a query parser tripping on weird characters in the input
+ searcher = index.searcher()
+ query = whoosh.query.Term('name', name.lower())
+ results = searcher.search(query)
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
+ results = []
for suggestion in speller.suggest(name, 3):
- results.extend( index.find(suggestion, parser=parser) )
+ query = whoosh.query.Term('name', suggestion)
+ results.extend(searcher.search(query))
# Convert results to db objects
objects = []