class SegmentReader(IndexReader):
GZIP_CACHES = False
def __init__(self, storage, schema, segment):
self.storage = storage
self.schema = schema
self.segment = segment
if hasattr(self.segment, "uuid"):
self.uuid_string = str(self.segment.uuid)
else:
import uuid
self.uuid_string = str(uuid.uuid4())
# Term index
tf = storage.open_file(segment.termsindex_filename)
self.termsindex = TermIndexReader(tf)
# Term postings file, vector index, and vector postings: lazy load
self.postfile = None
self.vectorindex = None
self.vpostfile = None
# Stored fields file
sf = storage.open_file(segment.storedfields_filename, mapped=False)
self.storedfields = StoredFieldReader(sf)
# Field length file
self.fieldlengths = None
if self.schema.has_scorable_fields():
flf = storage.open_file(segment.fieldlengths_filename)
self.fieldlengths = LengthReader(flf, segment.doc_count_all())
# Copy methods from underlying segment
self.has_deletions = segment.has_deletions
self.is_deleted = segment.is_deleted
self.doc_count = segment.doc_count
# Postings file
self.postfile = self.storage.open_file(segment.termposts_filename,
mapped=False)
self.dc = segment.doc_count_all()
assert self.dc == self.storedfields.length
self.set_caching_policy()
self.is_closed = False
self._sync_lock = Lock()
def generation(self):
return self.segment.generation
def _open_vectors(self):
if self.vectorindex:
return
storage, segment = self.storage, self.segment
# Vector index
vf = storage.open_file(segment.vectorindex_filename)
self.vectorindex = TermVectorReader(vf)
# Vector postings file
self.vpostfile = storage.open_file(segment.vectorposts_filename,
mapped=False)
def __repr__(self):
return "%s(%s)" % (self.__class__.__name__, self.segment)
@protected
def __contains__(self, term):
return term in self.termsindex
def close(self):
self.storedfields.close()
self.termsindex.close()
if self.postfile:
self.postfile.close()
if self.vectorindex:
self.vectorindex.close()
if self.vpostfile:
self.vpostfile.close()
#if self.fieldlengths:
# self.fieldlengths.close()
self.caching_policy = None
self.is_closed = True
def doc_count_all(self):
return self.dc
@protected
def stored_fields(self, docnum):
schema = self.schema
return dict(item for item in self.storedfields[docnum].iteritems()
if item[0] in schema)
@protected
def all_stored_fields(self):
is_deleted = self.segment.is_deleted
sf = self.stored_fields
for docnum in xrange(self.segment.doc_count_all()):
if not is_deleted(docnum):
yield sf(docnum)
def field_length(self, fieldname):
return self.segment.field_length(fieldname)
@protected
def doc_field_length(self, docnum, fieldname, default=0):
if self.fieldlengths is None:
return default
return self.fieldlengths.get(docnum, fieldname, default=default)
def max_field_length(self, fieldname):
return self.segment.max_field_length(fieldname)
@protected
def has_vector(self, docnum, fieldname):
if self.schema[fieldname].vector:
self._open_vectors()
return (docnum, fieldname) in self.vectorindex
else:
return False
@protected
def __iter__(self):
schema = self.schema
for (fieldname, t), (totalfreq, _, postcount) in self.termsindex:
if fieldname not in schema:
continue
yield (fieldname, t, postcount, totalfreq)
def _test_field(self, fieldname):
if fieldname not in self.schema:
raise TermNotFound("No field %r" % fieldname)
if self.schema[fieldname].format is None:
raise TermNotFound("Field %r is not indexed" % fieldname)
@protected
def iter_from(self, fieldname, text):
schema = self.schema
self._test_field(fieldname)
for (fn, t), (totalfreq, _, postcount) in self.termsindex.items_from(
(fieldname, text)):
if fn not in schema:
continue
yield (fn, t, postcount, totalfreq)
@protected
def _term_info(self, fieldname, text):
self._test_field(fieldname)
try:
return self.termsindex[fieldname, text]
except KeyError:
raise TermNotFound("%s:%r" % (fieldname, text))
def doc_frequency(self, fieldname, text):
try:
return self._term_info(fieldname, text)[2]
except TermNotFound:
return 0
def frequency(self, fieldname, text):
try:
return self._term_info(fieldname, text)[0]
except TermNotFound:
return 0
def lexicon(self, fieldname):
# The base class has a lexicon() implementation that uses iter_from()
# and throws away the value, but overriding to use
# FileTableReader.keys_from() is much, much faster.
self._test_field(fieldname)
# If a field cache happens to already be loaded for this field, use it
# instead of loading the field values from disk
if self.fieldcache_loaded(fieldname):
fieldcache = self.fieldcache(fieldname)
it = iter(fieldcache.texts)
# The first value in fieldcache.texts is the default; throw it away
it.next()
return it
return self.expand_prefix(fieldname, '')
@protected
def expand_prefix(self, fieldname, prefix):
# The base class has an expand_prefix() implementation that uses
# iter_from() and throws away the value, but overriding to use
# FileTableReader.keys_from() is much, much faster.
self._test_field(fieldname)
if self.fieldcache_loaded(fieldname):
texts = self.fieldcache(fieldname).texts
i = bisect_left(texts, prefix)
while i < len(texts) and texts[i].startswith(prefix):
yield texts[i]
i += 1
else:
for fn, t in self.termsindex.keys_from((fieldname, prefix)):
if fn != fieldname or not t.startswith(prefix):
break
yield t
def postings(self, fieldname, text, scorer=None):
try:
offset = self.termsindex[fieldname, text][1]
except KeyError:
raise TermNotFound("%s:%r" % (fieldname, text))
format = self.schema[fieldname].format
if isinstance(offset, (int, long)):
postreader = FilePostingReader(self.postfile,
offset,
format,
scorer=scorer,
fieldname=fieldname,
text=text)
else:
docids, weights, values, maxwol, minlength = offset
postreader = ListMatcher(docids,
weights,
values,
format,
scorer,
maxwol=maxwol,
minlength=minlength)
deleted = self.segment.deleted
if deleted:
postreader = FilterMatcher(postreader, deleted, exclude=True)
return postreader
def vector(self, docnum, fieldname):
if fieldname not in self.schema:
raise TermNotFound("No field %r" % fieldname)
vformat = self.schema[fieldname].vector
if not vformat:
raise Exception("No vectors are stored for field %r" % fieldname)
self._open_vectors()
offset = self.vectorindex.get((docnum, fieldname))
if offset is None:
raise Exception("No vector found for document"
" %s field %r" % (docnum, fieldname))
return FilePostingReader(self.vpostfile,
offset,
vformat,
stringids=True)
# Field cache methods
def supports_caches(self):
return True
def set_caching_policy(self, cp=None, save=True, storage=None):
"""This method lets you control the caching policy of the reader. You
can either pass a :class:`whoosh.filedb.fieldcache.FieldCachingPolicy`
as the first argument, *or* use the `save` and `storage` keywords to
alter the default caching policy::
# Use a custom field caching policy object
reader.set_caching_policy(MyPolicy())
# Use the default caching policy but turn off saving caches to disk
reader.set_caching_policy(save=False)
# Use the default caching policy but save caches to a custom storage
from whoosh.filedb.filestore import FileStorage
mystorage = FileStorage("path/to/cachedir")
reader.set_caching_policy(storage=mystorage)
:param cp: a :class:`whoosh.filedb.fieldcache.FieldCachingPolicy`
object. If this argument is not given, the default caching policy
is used.
:param save: save field caches to disk for re-use. If a caching policy
object is specified using `cp`, this argument is ignored.
:param storage: a custom :class:`whoosh.store.Storage` object to use
for saving field caches. If a caching policy object is specified
using `cp` or `save` is `False`, this argument is ignored.
"""
if not cp:
if save and storage is None:
storage = self.storage
else:
storage = None
cp = DefaultFieldCachingPolicy(self.segment.name, storage=storage)
if type(cp) is type:
cp = cp()
self.caching_policy = cp
def _fieldkey(self, fieldname):
return "%s/%s" % (self.uuid_string, fieldname)
def define_facets(self, name, qs, save=SAVE_BY_DEFAULT):
if name in self.schema:
raise Exception(
"Can't define facets using the name of a field (%r)" % name)
if self.fieldcache_available(name):
# Don't recreate the cache if it already exists
return
cache = self.caching_policy.get_class().from_lists(
qs, self.doc_count_all())
self.caching_policy.put(self._fieldkey(name), cache, save=save)
def fieldcache(self, fieldname, save=SAVE_BY_DEFAULT):
"""Returns a :class:`whoosh.filedb.fieldcache.FieldCache` object for
the given field.
:param fieldname: the name of the field to get a cache for.
:param save: if True (the default), the cache is saved to disk if it
doesn't already exist.
"""
key = self._fieldkey(fieldname)
fc = self.caching_policy.get(key)
if not fc:
fc = FieldCache.from_field(self, fieldname)
self.caching_policy.put(key, fc, save=save)
return fc
def fieldcache_available(self, fieldname):
"""Returns True if a field cache exists for the given field (either in
memory already or on disk).
"""
return self._fieldkey(fieldname) in self.caching_policy
def fieldcache_loaded(self, fieldname):
"""Returns True if a field cache for the given field is in memory.
"""
return self.caching_policy.is_loaded(self._fieldkey(fieldname))
def unload_fieldcache(self, name):
self.caching_policy.delete(self._fieldkey(name))
# Sorting and faceting methods
def key_fn(self, fields):
if isinstance(fields, basestring):
fields = (fields, )
if len(fields) > 1:
fcs = [self.fieldcache(fn) for fn in fields]
return lambda docnum: tuple(fc.key_for(docnum) for fc in fcs)
else:
return self.fieldcache(fields[0]).key_for
def sort_docs_by(self, fields, docnums, reverse=False):
keyfn = self.key_fn(fields)
return sorted(docnums, key=keyfn, reverse=reverse)
def key_docs_by(self, fields, docnums, limit, reverse=False, offset=0):
keyfn = self.key_fn(fields)
if limit is None:
# Don't bother sorting, the caller will do that
return [(keyfn(docnum), docnum + offset) for docnum in docnums]
else:
# A non-reversed sort (the usual case) is inefficient because we
# have to use nsmallest, but I can't think of a cleverer thing to
# do right now. I thought I had an idea, but I was wrong.
op = nlargest if reverse else nsmallest
return op(limit,
((keyfn(docnum), docnum + offset) for docnum in docnums))
class SegmentReader(IndexReader):
GZIP_CACHES = False
def __init__(self, storage, schema, segment):
self.storage = storage
self.schema = schema
self.segment = segment
if hasattr(self.segment, "uuid"):
self.uuid_string = str(self.segment.uuid)
else:
import uuid
self.uuid_string = str(uuid.uuid4())
# Term index
tf = storage.open_file(segment.termsindex_filename)
self.termsindex = TermIndexReader(tf)
# Term vector index, and vector postings: lazy load
self.vectorindex = None
self.vpostfile = None
# Stored fields file
sf = storage.open_file(segment.storedfields_filename, mapped=False)
self.storedfields = StoredFieldReader(sf)
# Field length file
self.fieldlengths = None
if self.schema.has_scorable_fields():
flf = storage.open_file(segment.fieldlengths_filename)
self.fieldlengths = LengthReader(flf, segment.doc_count_all())
# Copy info from underlying segment
self._has_deletions = segment.has_deletions()
self._doc_count = segment.doc_count()
# Postings file
self.postfile = self.storage.open_file(segment.termposts_filename,
mapped=False)
# Dawg file
self.dawg = None
if any(field.spelling for field in self.schema):
fname = segment.dawg_filename
if self.storage.file_exists(fname):
dawgfile = self.storage.open_file(fname, mapped=False)
self.dawg = DiskNode.load(dawgfile, expand=False)
self.dc = segment.doc_count_all()
assert self.dc == self.storedfields.length
self.set_caching_policy()
self.is_closed = False
self._sync_lock = Lock()
def has_deletions(self):
return self._has_deletions
def doc_count(self):
return self._doc_count
def is_deleted(self, docnum):
return self.segment.is_deleted(docnum)
def generation(self):
return self.segment.generation
def _open_vectors(self):
if self.vectorindex:
return
storage, segment = self.storage, self.segment
# Vector index
vf = storage.open_file(segment.vectorindex_filename)
self.vectorindex = TermVectorReader(vf)
# Vector postings file
self.vpostfile = storage.open_file(segment.vectorposts_filename,
mapped=False)
def __repr__(self):
return "%s(%s)" % (self.__class__.__name__, self.segment)
def __contains__(self, term):
return term in self.termsindex
def close(self):
self.storedfields.close()
self.termsindex.close()
if self.postfile:
self.postfile.close()
if self.vectorindex:
self.vectorindex.close()
if self.vpostfile:
self.vpostfile.close()
#if self.fieldlengths:
# self.fieldlengths.close()
self.caching_policy = None
self.is_closed = True
def doc_count_all(self):
return self.dc
def stored_fields(self, docnum):
assert docnum >= 0
schema = self.schema
return dict(item for item
in iteritems(self.storedfields[docnum])
if item[0] in schema)
def all_stored_fields(self):
is_deleted = self.segment.is_deleted
sf = self.stored_fields
for docnum in xrange(self.segment.doc_count_all()):
if not is_deleted(docnum):
yield sf(docnum)
def field_length(self, fieldname):
return self.segment.field_length(fieldname)
def min_field_length(self, fieldname):
return self.segment.min_field_length(fieldname)
def max_field_length(self, fieldname):
return self.segment.max_field_length(fieldname)
def doc_field_length(self, docnum, fieldname, default=0):
if self.fieldlengths is None:
return default
return self.fieldlengths.get(docnum, fieldname, default=default)
def has_vector(self, docnum, fieldname):
if self.schema[fieldname].vector:
self._open_vectors()
return (docnum, fieldname) in self.vectorindex
else:
return False
def _test_field(self, fieldname):
if fieldname not in self.schema:
raise TermNotFound("No field %r" % fieldname)
if self.schema[fieldname].format is None:
raise TermNotFound("Field %r is not indexed" % fieldname)
def all_terms(self):
schema = self.schema
return ((fieldname, text) for fieldname, text
in self.termsindex.keys()
if fieldname in schema)
def terms_from(self, fieldname, prefix):
self._test_field(fieldname)
schema = self.schema
return ((fname, text) for fname, text
in self.termsindex.keys_from((fieldname, prefix))
if fname in schema)
def term_info(self, fieldname, text):
self._test_field(fieldname)
try:
return self.termsindex[fieldname, text]
except KeyError:
raise TermNotFound("%s:%r" % (fieldname, text))
def _texts_in_fieldcache(self, fieldname, prefix=''):
# The first value in a fieldcache is the default
texts = self.fieldcache(fieldname).texts[1:]
if prefix:
i = bisect_left(texts, prefix)
while i < len(texts) and texts[i].startswith(prefix):
yield texts[i]
i += 1
else:
for text in texts:
yield text
def expand_prefix(self, fieldname, prefix):
self._test_field(fieldname)
# If a fieldcache for the field is already loaded, we already have the
# values for the field in memory, so just yield them from there
if self.fieldcache_loaded(fieldname):
return self._texts_in_fieldcache(fieldname, prefix)
else:
return IndexReader.expand_prefix(self, fieldname, prefix)
def lexicon(self, fieldname):
self._test_field(fieldname)
# If a fieldcache for the field is already loaded, we already have the
# values for the field in memory, so just yield them from there
if self.fieldcache_loaded(fieldname):
return self._texts_in_fieldcache(fieldname)
else:
return IndexReader.lexicon(self, fieldname)
def __iter__(self):
schema = self.schema
return ((term, terminfo) for term, terminfo
in self.termsindex.items()
if term[0] in schema)
def iter_from(self, fieldname, text):
schema = self.schema
self._test_field(fieldname)
for term, terminfo in self.termsindex.items_from((fieldname, text)):
if term[0] not in schema:
continue
yield (term, terminfo)
def frequency(self, fieldname, text):
self._test_field(fieldname)
try:
return self.termsindex.frequency((fieldname, text))
except KeyError:
return 0
def doc_frequency(self, fieldname, text):
self._test_field(fieldname)
try:
return self.termsindex.doc_frequency((fieldname, text))
except KeyError:
return 0
def postings(self, fieldname, text, scorer=None):
try:
terminfo = self.termsindex[fieldname, text]
except KeyError:
raise TermNotFound("%s:%r" % (fieldname, text))
format = self.schema[fieldname].format
postings = terminfo.postings
if isinstance(postings, integer_types):
postreader = FilePostingReader(self.postfile, postings, format,
scorer=scorer,
term=(fieldname, text))
else:
docids, weights, values = postings
postreader = ListMatcher(docids, weights, values, format,
scorer=scorer, term=(fieldname, text),
terminfo=terminfo)
deleted = self.segment.deleted
if deleted:
postreader = FilterMatcher(postreader, deleted, exclude=True)
return postreader
def vector(self, docnum, fieldname):
if fieldname not in self.schema:
raise TermNotFound("No field %r" % fieldname)
vformat = self.schema[fieldname].vector
if not vformat:
raise Exception("No vectors are stored for field %r" % fieldname)
self._open_vectors()
try:
offset = self.vectorindex.get((docnum, fieldname))
except KeyError:
raise KeyError("No vector found for document "
"%s field %r" % (docnum, fieldname))
return FilePostingReader(self.vpostfile, offset, vformat,
stringids=True)
# DAWG methods
def has_word_graph(self, fieldname):
if fieldname not in self.schema:
return False
if not self.schema[fieldname].spelling:
return False
if self.dawg:
return fieldname in self.dawg
return False
def word_graph(self, fieldname):
if not self.has_word_graph(fieldname):
raise Exception("No word graph for field %r" % fieldname)
return self.dawg.edge(fieldname)
# Field cache methods
def supports_caches(self):
return True
def set_caching_policy(self, cp=None, save=True, storage=None):
"""This method lets you control the caching policy of the reader. You
can either pass a :class:`whoosh.filedb.fieldcache.FieldCachingPolicy`
as the first argument, *or* use the `save` and `storage` keywords to
alter the default caching policy::
# Use a custom field caching policy object
reader.set_caching_policy(MyPolicy())
# Use the default caching policy but turn off saving caches to disk
reader.set_caching_policy(save=False)
# Use the default caching policy but save caches to a custom
# storage
from whoosh.filedb.filestore import FileStorage
mystorage = FileStorage("path/to/cachedir")
reader.set_caching_policy(storage=mystorage)
:param cp: a :class:`whoosh.filedb.fieldcache.FieldCachingPolicy`
object. If this argument is not given, the default caching policy
is used.
:param save: save field caches to disk for re-use. If a caching policy
object is specified using `cp`, this argument is ignored.
:param storage: a custom :class:`whoosh.store.Storage` object to use
for saving field caches. If a caching policy object is specified
using `cp` or `save` is `False`, this argument is ignored.
"""
if not cp:
if save and storage is None:
storage = self.storage
else:
storage = None
cp = DefaultFieldCachingPolicy(self.segment.name, storage=storage)
if type(cp) is type:
cp = cp()
self.caching_policy = cp
def _fieldkey(self, fieldname):
return "%s/%s" % (self.uuid_string, fieldname)
def fieldcache(self, fieldname, save=SAVE_BY_DEFAULT):
"""Returns a :class:`whoosh.filedb.fieldcache.FieldCache` object for
the given field.
:param fieldname: the name of the field to get a cache for.
:param save: if True (the default), the cache is saved to disk if it
doesn't already exist.
"""
key = self._fieldkey(fieldname)
fc = self.caching_policy.get(key)
if not fc:
fc = FieldCache.from_field(self, fieldname)
self.caching_policy.put(key, fc, save=save)
return fc
def fieldcache_available(self, fieldname):
"""Returns True if a field cache exists for the given field (either in
memory already or on disk).
"""
return self._fieldkey(fieldname) in self.caching_policy
def fieldcache_loaded(self, fieldname):
"""Returns True if a field cache for the given field is in memory.
"""
return self.caching_policy.is_loaded(self._fieldkey(fieldname))
def unload_fieldcache(self, name):
self.caching_policy.delete(self._fieldkey(name))
class SegmentReader(IndexReader):
GZIP_CACHES = False
def __init__(self, storage, schema, segment):
self.storage = storage
self.schema = schema
self.segment = segment
if hasattr(self.segment, "uuid"):
self.uuid_string = str(self.segment.uuid)
else:
import uuid
self.uuid_string = str(uuid.uuid4())
# Term index
tf = storage.open_file(segment.termsindex_filename)
self.termsindex = TermIndexReader(tf)
# Term vector index, and vector postings: lazy load
self.vectorindex = None
self.vpostfile = None
# Stored fields file
sf = storage.open_file(segment.storedfields_filename, mapped=False)
self.storedfields = StoredFieldReader(sf)
# Field length file
self.fieldlengths = None
if self.schema.has_scorable_fields():
flf = storage.open_file(segment.fieldlengths_filename)
self.fieldlengths = LengthReader(flf, segment.doc_count_all())
# Copy info from underlying segment
self._has_deletions = segment.has_deletions()
self._doc_count = segment.doc_count()
# Postings file
self.postfile = self.storage.open_file(segment.termposts_filename,
mapped=False)
# Dawg file
self.dawg = None
if any(field.spelling for field in self.schema):
fname = segment.dawg_filename
if self.storage.file_exists(fname):
dawgfile = self.storage.open_file(fname, mapped=False)
self.dawg = DiskNode.load(dawgfile, expand=False)
self.dc = segment.doc_count_all()
assert self.dc == self.storedfields.length
self.set_caching_policy()
self.is_closed = False
self._sync_lock = Lock()
def has_deletions(self):
return self._has_deletions
def doc_count(self):
return self._doc_count
def is_deleted(self, docnum):
return self.segment.is_deleted(docnum)
def generation(self):
return self.segment.generation
def _open_vectors(self):
if self.vectorindex:
return
storage, segment = self.storage, self.segment
# Vector index
vf = storage.open_file(segment.vectorindex_filename)
self.vectorindex = TermVectorReader(vf)
# Vector postings file
self.vpostfile = storage.open_file(segment.vectorposts_filename,
mapped=False)
def __repr__(self):
return "%s(%s)" % (self.__class__.__name__, self.segment)
def __contains__(self, term):
return term in self.termsindex
def close(self):
self.storedfields.close()
self.termsindex.close()
if self.postfile:
self.postfile.close()
if self.vectorindex:
self.vectorindex.close()
if self.vpostfile:
self.vpostfile.close()
#if self.fieldlengths:
# self.fieldlengths.close()
self.caching_policy = None
self.is_closed = True
def doc_count_all(self):
return self.dc
def stored_fields(self, docnum):
assert docnum >= 0
schema = self.schema
return dict(item for item in iteritems(self.storedfields[docnum])
if item[0] in schema)
def all_stored_fields(self):
is_deleted = self.segment.is_deleted
sf = self.stored_fields
for docnum in xrange(self.segment.doc_count_all()):
if not is_deleted(docnum):
yield sf(docnum)
def field_length(self, fieldname):
return self.segment.field_length(fieldname)
def min_field_length(self, fieldname):
return self.segment.min_field_length(fieldname)
def max_field_length(self, fieldname):
return self.segment.max_field_length(fieldname)
def doc_field_length(self, docnum, fieldname, default=0):
if self.fieldlengths is None:
return default
return self.fieldlengths.get(docnum, fieldname, default=default)
def has_vector(self, docnum, fieldname):
if self.schema[fieldname].vector:
self._open_vectors()
return (docnum, fieldname) in self.vectorindex
else:
return False
def _test_field(self, fieldname):
if fieldname not in self.schema:
raise TermNotFound("No field %r" % fieldname)
if self.schema[fieldname].format is None:
raise TermNotFound("Field %r is not indexed" % fieldname)
def all_terms(self):
schema = self.schema
return ((fieldname, text)
for fieldname, text in self.termsindex.keys()
if fieldname in schema)
def terms_from(self, fieldname, prefix):
self._test_field(fieldname)
schema = self.schema
return ((fname, text)
for fname, text in self.termsindex.keys_from((fieldname,
prefix))
if fname in schema)
def term_info(self, fieldname, text):
self._test_field(fieldname)
try:
return self.termsindex[fieldname, text]
except KeyError:
raise TermNotFound("%s:%r" % (fieldname, text))
def _texts_in_fieldcache(self, fieldname, prefix=''):
# The first value in a fieldcache is the default
texts = self.fieldcache(fieldname).texts[1:]
if prefix:
i = bisect_left(texts, prefix)
while i < len(texts) and texts[i].startswith(prefix):
yield texts[i]
i += 1
else:
for text in texts:
yield text
def expand_prefix(self, fieldname, prefix):
self._test_field(fieldname)
# If a fieldcache for the field is already loaded, we already have the
# values for the field in memory, so just yield them from there
if self.fieldcache_loaded(fieldname):
return self._texts_in_fieldcache(fieldname, prefix)
else:
return IndexReader.expand_prefix(self, fieldname, prefix)
def lexicon(self, fieldname):
self._test_field(fieldname)
# If a fieldcache for the field is already loaded, we already have the
# values for the field in memory, so just yield them from there
if self.fieldcache_loaded(fieldname):
return self._texts_in_fieldcache(fieldname)
else:
return IndexReader.lexicon(self, fieldname)
def __iter__(self):
schema = self.schema
return ((term, terminfo) for term, terminfo in self.termsindex.items()
if term[0] in schema)
def iter_from(self, fieldname, text):
schema = self.schema
self._test_field(fieldname)
for term, terminfo in self.termsindex.items_from((fieldname, text)):
if term[0] not in schema:
continue
yield (term, terminfo)
def frequency(self, fieldname, text):
self._test_field(fieldname)
try:
return self.termsindex.frequency((fieldname, text))
except KeyError:
return 0
def doc_frequency(self, fieldname, text):
self._test_field(fieldname)
try:
return self.termsindex.doc_frequency((fieldname, text))
except KeyError:
return 0
def postings(self, fieldname, text, scorer=None):
try:
terminfo = self.termsindex[fieldname, text]
except KeyError:
raise TermNotFound("%s:%r" % (fieldname, text))
format = self.schema[fieldname].format
postings = terminfo.postings
if isinstance(postings, integer_types):
postreader = FilePostingReader(self.postfile,
postings,
format,
scorer=scorer,
term=(fieldname, text))
else:
docids, weights, values = postings
postreader = ListMatcher(docids,
weights,
values,
format,
scorer=scorer,
term=(fieldname, text),
terminfo=terminfo)
deleted = self.segment.deleted
if deleted:
postreader = FilterMatcher(postreader, deleted, exclude=True)
return postreader
def vector(self, docnum, fieldname):
if fieldname not in self.schema:
raise TermNotFound("No field %r" % fieldname)
vformat = self.schema[fieldname].vector
if not vformat:
raise Exception("No vectors are stored for field %r" % fieldname)
self._open_vectors()
try:
offset = self.vectorindex.get((docnum, fieldname))
except KeyError:
raise KeyError("No vector found for document "
"%s field %r" % (docnum, fieldname))
return FilePostingReader(self.vpostfile,
offset,
vformat,
stringids=True)
# DAWG methods
def has_word_graph(self, fieldname):
if fieldname not in self.schema:
return False
if not self.schema[fieldname].spelling:
return False
if self.dawg:
return fieldname in self.dawg
return False
def word_graph(self, fieldname):
if not self.has_word_graph(fieldname):
raise Exception("No word graph for field %r" % fieldname)
return self.dawg.edge(fieldname)
# Field cache methods
def supports_caches(self):
return True
def set_caching_policy(self, cp=None, save=True, storage=None):
"""This method lets you control the caching policy of the reader. You
can either pass a :class:`whoosh.filedb.fieldcache.FieldCachingPolicy`
as the first argument, *or* use the `save` and `storage` keywords to
alter the default caching policy::
# Use a custom field caching policy object
reader.set_caching_policy(MyPolicy())
# Use the default caching policy but turn off saving caches to disk
reader.set_caching_policy(save=False)
# Use the default caching policy but save caches to a custom
# storage
from whoosh.filedb.filestore import FileStorage
mystorage = FileStorage("path/to/cachedir")
reader.set_caching_policy(storage=mystorage)
:param cp: a :class:`whoosh.filedb.fieldcache.FieldCachingPolicy`
object. If this argument is not given, the default caching policy
is used.
:param save: save field caches to disk for re-use. If a caching policy
object is specified using `cp`, this argument is ignored.
:param storage: a custom :class:`whoosh.store.Storage` object to use
for saving field caches. If a caching policy object is specified
using `cp` or `save` is `False`, this argument is ignored.
"""
if not cp:
if save and storage is None:
storage = self.storage
elif not save:
storage = None
cp = DefaultFieldCachingPolicy(self.segment.name, storage=storage)
if type(cp) is type:
cp = cp()
self.caching_policy = cp
def _fieldkey(self, fieldname):
return "%s/%s" % (self.uuid_string, fieldname)
def fieldcache(self, fieldname, save=SAVE_BY_DEFAULT):
"""Returns a :class:`whoosh.filedb.fieldcache.FieldCache` object for
the given field.
:param fieldname: the name of the field to get a cache for.
:param save: if True (the default), the cache is saved to disk if it
doesn't already exist.
"""
key = self._fieldkey(fieldname)
fc = self.caching_policy.get(key)
if not fc:
fc = FieldCache.from_field(self, fieldname)
self.caching_policy.put(key, fc, save=save)
return fc
def fieldcache_available(self, fieldname):
"""Returns True if a field cache exists for the given field (either in
memory already or on disk).
"""
return self._fieldkey(fieldname) in self.caching_policy
def fieldcache_loaded(self, fieldname):
"""Returns True if a field cache for the given field is in memory.
"""
return self.caching_policy.is_loaded(self._fieldkey(fieldname))
def unload_fieldcache(self, name):
self.caching_policy.delete(self._fieldkey(name))
class SegmentReader(IndexReader):
GZIP_CACHES = False
def __init__(self, storage, schema, segment):
self.storage = storage
self.schema = schema
self.segment = segment
if hasattr(self.segment, "uuid"):
self.uuid_string = str(self.segment.uuid)
else:
import uuid
self.uuid_string = str(uuid.uuid4())
# Term index
tf = storage.open_file(segment.termsindex_filename)
self.termsindex = TermIndexReader(tf)
# Term postings file, vector index, and vector postings: lazy load
self.postfile = None
self.vectorindex = None
self.vpostfile = None
# Stored fields file
sf = storage.open_file(segment.storedfields_filename, mapped=False)
self.storedfields = StoredFieldReader(sf)
# Field length file
self.fieldlengths = None
if self.schema.has_scorable_fields():
flf = storage.open_file(segment.fieldlengths_filename)
self.fieldlengths = LengthReader(flf, segment.doc_count_all())
# Copy methods from underlying segment
self.has_deletions = segment.has_deletions
self.is_deleted = segment.is_deleted
self.doc_count = segment.doc_count
# Postings file
self.postfile = self.storage.open_file(segment.termposts_filename,
mapped=False)
self.dc = segment.doc_count_all()
assert self.dc == self.storedfields.length
self.set_caching_policy()
self.is_closed = False
self._sync_lock = Lock()
def generation(self):
return self.segment.generation
def _open_vectors(self):
if self.vectorindex:
return
storage, segment = self.storage, self.segment
# Vector index
vf = storage.open_file(segment.vectorindex_filename)
self.vectorindex = TermVectorReader(vf)
# Vector postings file
self.vpostfile = storage.open_file(segment.vectorposts_filename,
mapped=False)
def __repr__(self):
return "%s(%s)" % (self.__class__.__name__, self.segment)
@protected
def __contains__(self, term):
return term in self.termsindex
def close(self):
self.storedfields.close()
self.termsindex.close()
if self.postfile:
self.postfile.close()
if self.vectorindex:
self.vectorindex.close()
if self.vpostfile:
self.vpostfile.close()
#if self.fieldlengths:
# self.fieldlengths.close()
self.caching_policy = None
self.is_closed = True
def doc_count_all(self):
return self.dc
@protected
def stored_fields(self, docnum):
schema = self.schema
return dict(item for item
in self.storedfields[docnum].iteritems()
if item[0] in schema)
@protected
def all_stored_fields(self):
is_deleted = self.segment.is_deleted
sf = self.stored_fields
for docnum in xrange(self.segment.doc_count_all()):
if not is_deleted(docnum):
yield sf(docnum)
def field_length(self, fieldname):
return self.segment.field_length(fieldname)
@protected
def doc_field_length(self, docnum, fieldname, default=0):
if self.fieldlengths is None:
return default
return self.fieldlengths.get(docnum, fieldname, default=default)
def max_field_length(self, fieldname):
return self.segment.max_field_length(fieldname)
@protected
def has_vector(self, docnum, fieldname):
if self.schema[fieldname].vector:
self._open_vectors()
return (docnum, fieldname) in self.vectorindex
else:
return False
@protected
def __iter__(self):
schema = self.schema
for (fieldname, t), (totalfreq, _, postcount) in self.termsindex:
if fieldname not in schema:
continue
yield (fieldname, t, postcount, totalfreq)
def _test_field(self, fieldname):
if fieldname not in self.schema:
raise TermNotFound("No field %r" % fieldname)
if self.schema[fieldname].format is None:
raise TermNotFound("Field %r is not indexed" % fieldname)
@protected
def iter_from(self, fieldname, text):
schema = self.schema
self._test_field(fieldname)
for (fn, t), (totalfreq, _, postcount) in self.termsindex.items_from((fieldname, text)):
if fn not in schema:
continue
yield (fn, t, postcount, totalfreq)
@protected
def _term_info(self, fieldname, text):
self._test_field(fieldname)
try:
return self.termsindex[fieldname, text]
except KeyError:
raise TermNotFound("%s:%r" % (fieldname, text))
def doc_frequency(self, fieldname, text):
self._test_field(fieldname)
try:
return self._term_info(fieldname, text)[2]
except TermNotFound:
return 0
def frequency(self, fieldname, text):
self._test_field(fieldname)
try:
return self._term_info(fieldname, text)[0]
except TermNotFound:
return 0
def lexicon(self, fieldname):
# The base class has a lexicon() implementation that uses iter_from()
# and throws away the value, but overriding to use
# FileTableReader.keys_from() is much, much faster.
self._test_field(fieldname)
# If a field cache happens to already be loaded for this field, use it
# instead of loading the field values from disk
if self.fieldcache_loaded(fieldname):
fieldcache = self.fieldcache(fieldname)
it = iter(fieldcache.texts)
# The first value in fieldcache.texts is the default; throw it away
it.next()
return it
return self.expand_prefix(fieldname, '')
@protected
def expand_prefix(self, fieldname, prefix):
# The base class has an expand_prefix() implementation that uses
# iter_from() and throws away the value, but overriding to use
# FileTableReader.keys_from() is much, much faster.
self._test_field(fieldname)
if self.fieldcache_loaded(fieldname):
texts = self.fieldcache(fieldname).texts
i = bisect_left(texts, prefix)
while i < len(texts) and texts[i].startswith(prefix):
yield texts[i]
i += 1
else:
for fn, t in self.termsindex.keys_from((fieldname, prefix)):
if fn != fieldname or not t.startswith(prefix):
break
yield t
def postings(self, fieldname, text, scorer=None):
self._test_field(fieldname)
format = self.schema[fieldname].format
try:
offset = self.termsindex[fieldname, text][1]
except KeyError:
raise TermNotFound("%s:%r" % (fieldname, text))
if isinstance(offset, (int, long)):
postreader = FilePostingReader(self.postfile, offset, format,
scorer=scorer, fieldname=fieldname,
text=text)
else:
docids, weights, values, maxwol, minlength = offset
postreader = ListMatcher(docids, weights, values, format, scorer,
maxwol=maxwol, minlength=minlength)
deleted = self.segment.deleted
if deleted:
postreader = FilterMatcher(postreader, deleted, exclude=True)
return postreader
def vector(self, docnum, fieldname):
if fieldname not in self.schema:
raise TermNotFound("No field %r" % fieldname)
vformat = self.schema[fieldname].vector
if not vformat:
raise Exception("No vectors are stored for field %r" % fieldname)
self._open_vectors()
offset = self.vectorindex.get((docnum, fieldname))
if offset is None:
raise Exception("No vector found for document"
" %s field %r" % (docnum, fieldname))
return FilePostingReader(self.vpostfile, offset, vformat, stringids=True)
# Field cache methods
def supports_caches(self):
return True
def set_caching_policy(self, cp=None, save=True, storage=None):
"""This method lets you control the caching policy of the reader. You
can either pass a :class:`whoosh.filedb.fieldcache.FieldCachingPolicy`
as the first argument, *or* use the `save` and `storage` keywords to
alter the default caching policy::
# Use a custom field caching policy object
reader.set_caching_policy(MyPolicy())
# Use the default caching policy but turn off saving caches to disk
reader.set_caching_policy(save=False)
# Use the default caching policy but save caches to a custom storage
from whoosh.filedb.filestore import FileStorage
mystorage = FileStorage("path/to/cachedir")
reader.set_caching_policy(storage=mystorage)
:param cp: a :class:`whoosh.filedb.fieldcache.FieldCachingPolicy`
object. If this argument is not given, the default caching policy
is used.
:param save: save field caches to disk for re-use. If a caching policy
object is specified using `cp`, this argument is ignored.
:param storage: a custom :class:`whoosh.store.Storage` object to use
for saving field caches. If a caching policy object is specified
using `cp` or `save` is `False`, this argument is ignored.
"""
if not cp:
if save and storage is None:
storage = self.storage
else:
storage = None
cp = DefaultFieldCachingPolicy(self.segment.name, storage=storage)
if type(cp) is type:
cp = cp()
self.caching_policy = cp
def _fieldkey(self, fieldname):
return "%s/%s" % (self.uuid_string, fieldname)
def define_facets(self, name, qs, save=SAVE_BY_DEFAULT):
if name in self.schema:
raise Exception("Can't define facets using the name of a field (%r)" % name)
if self.fieldcache_available(name):
# Don't recreate the cache if it already exists
return
cache = self.caching_policy.get_class().from_lists(qs, self.doc_count_all())
self.caching_policy.put(self._fieldkey(name), cache, save=save)
def fieldcache(self, fieldname, save=SAVE_BY_DEFAULT):
"""Returns a :class:`whoosh.filedb.fieldcache.FieldCache` object for
the given field.
:param fieldname: the name of the field to get a cache for.
:param save: if True (the default), the cache is saved to disk if it
doesn't already exist.
"""
key = self._fieldkey(fieldname)
fc = self.caching_policy.get(key)
if not fc:
fc = FieldCache.from_field(self, fieldname)
self.caching_policy.put(key, fc, save=save)
return fc
def fieldcache_available(self, fieldname):
"""Returns True if a field cache exists for the given field (either in
memory already or on disk).
"""
return self._fieldkey(fieldname) in self.caching_policy
def fieldcache_loaded(self, fieldname):
"""Returns True if a field cache for the given field is in memory.
"""
return self.caching_policy.is_loaded(self._fieldkey(fieldname))
def unload_fieldcache(self, name):
self.caching_policy.delete(self._fieldkey(name))
# Sorting and faceting methods
def key_fn(self, fields):
if isinstance(fields, basestring):
fields = (fields, )
if len(fields) > 1:
fcs = [self.fieldcache(fn) for fn in fields]
return lambda docnum: tuple(fc.key_for(docnum) for fc in fcs)
else:
return self.fieldcache(fields[0]).key_for
def sort_docs_by(self, fields, docnums, reverse=False):
keyfn = self.key_fn(fields)
return sorted(docnums, key=keyfn, reverse=reverse)
def key_docs_by(self, fields, docnums, limit, reverse=False, offset=0):
keyfn = self.key_fn(fields)
if limit is None:
# Don't bother sorting, the caller will do that
return [(keyfn(docnum), docnum + offset) for docnum in docnums]
else:
# A non-reversed sort (the usual case) is inefficient because we
# have to use nsmallest, but I can't think of a cleverer thing to
# do right now. I thought I had an idea, but I was wrong.
op = nlargest if reverse else nsmallest
return op(limit, ((keyfn(docnum), docnum + offset)
for docnum in docnums))
class SegmentReader(IndexReader):
def __init__(self, storage, schema, segment, generation=None):
self.storage = storage
self.schema = schema
self.segment = segment
self._generation = generation
# Term index
tf = storage.open_file(segment.termsindex_filename)
self.termsindex = TermIndexReader(tf)
# Term postings file, vector index, and vector postings: lazy load
self.postfile = None
self.vectorindex = None
self.vpostfile = None
# Stored fields file
sf = storage.open_file(segment.storedfields_filename, mapped=False)
self.storedfields = StoredFieldReader(sf)
# Field length file
self.fieldlengths = None
if self.schema.has_scorable_fields():
flf = storage.open_file(segment.fieldlengths_filename)
self.fieldlengths = LengthReader(flf, segment.doc_count_all())
# Copy methods from underlying segment
self.has_deletions = segment.has_deletions
self.is_deleted = segment.is_deleted
self.doc_count = segment.doc_count
# Postings file
self.postfile = self.storage.open_file(segment.termposts_filename,
mapped=False)
self.dc = segment.doc_count_all()
assert self.dc == self.storedfields.length
self.is_closed = False
self._sync_lock = Lock()
def _open_vectors(self):
if self.vectorindex: return
storage, segment = self.storage, self.segment
# Vector index
vf = storage.open_file(segment.vectorindex_filename)
self.vectorindex = TermVectorReader(vf)
# Vector postings file
self.vpostfile = storage.open_file(segment.vectorposts_filename,
mapped=False)
def __repr__(self):
return "%s(%s)" % (self.__class__.__name__, self.segment)
@protected
def __contains__(self, term):
return term in self.termsindex
def generation(self):
return self._generation
def close(self):
self.storedfields.close()
self.termsindex.close()
if self.postfile:
self.postfile.close()
if self.vectorindex:
self.vectorindex.close()
#if self.fieldlengths:
# self.fieldlengths.close()
self.is_closed = True
def doc_count_all(self):
return self.dc
def field(self, fieldname):
return self.schema[fieldname]
def scorable(self, fieldname):
return self.schema[fieldname].scorable
def scorable_names(self):
return self.schema.scorable_names()
def vector_names(self):
return self.schema.vector_names()
def format(self, fieldname):
return self.schema[fieldname].format
def vector_format(self, fieldname):
return self.schema[fieldname].vector
@protected
def stored_fields(self, docnum):
schema = self.schema
return dict(item for item in self.storedfields[docnum].iteritems()
if item[0] in schema)
@protected
def all_stored_fields(self):
is_deleted = self.segment.is_deleted
sf = self.stored_fields
for docnum in xrange(self.segment.doc_count_all()):
if not is_deleted(docnum):
yield sf(docnum)
def field_length(self, fieldname):
return self.segment.field_length(fieldname)
@protected
def doc_field_length(self, docnum, fieldname, default=0):
if self.fieldlengths is None: return default
return self.fieldlengths.get(docnum, fieldname, default=default)
def max_field_length(self, fieldname):
return self.segment.max_field_length(fieldname)
@protected
def has_vector(self, docnum, fieldname):
self._open_vectors()
return (docnum, fieldname) in self.vectorindex
@protected
def __iter__(self):
schema = self.schema
for (fieldname, t), (totalfreq, _, postcount) in self.termsindex:
if fieldname not in schema:
continue
yield (fieldname, t, postcount, totalfreq)
def _test_field(self, fieldname):
if fieldname not in self.schema:
raise TermNotFound("No field %r" % fieldname)
if self.schema[fieldname].format is None:
raise TermNotFound("Field %r is not indexed" % fieldname)
@protected
def iter_from(self, fieldname, text):
schema = self.schema
self._test_field(fieldname)
for (fn, t), (totalfreq, _, postcount) in self.termsindex.items_from(
(fieldname, text)):
if fn not in schema:
continue
yield (fn, t, postcount, totalfreq)
@protected
def _term_info(self, fieldname, text):
self._test_field(fieldname)
try:
return self.termsindex[(fieldname, text)]
except KeyError:
raise TermNotFound("%s:%r" % (fieldname, text))
def doc_frequency(self, fieldname, text):
self._test_field(fieldname)
try:
return self._term_info(fieldname, text)[2]
except TermNotFound:
return 0
def frequency(self, fieldname, text):
self._test_field(fieldname)
try:
return self._term_info(fieldname, text)[0]
except TermNotFound:
return 0
def lexicon(self, fieldname):
# The base class has a lexicon() implementation that uses iter_from()
# and throws away the value, but overriding to use
# FileTableReader.keys_from() is much, much faster.
self._test_field(fieldname)
return self.expand_prefix(fieldname, '')
@protected
def expand_prefix(self, fieldname, prefix):
# The base class has an expand_prefix() implementation that uses
# iter_from() and throws away the value, but overriding to use
# FileTableReader.keys_from() is much, much faster.
self._test_field(fieldname)
for fn, t in self.termsindex.keys_from((fieldname, prefix)):
if fn != fieldname or not t.startswith(prefix):
return
yield t
def postings(self, fieldname, text, exclude_docs=frozenset(), scorer=None):
self._test_field(fieldname)
format = self.format(fieldname)
try:
offset = self.termsindex[(fieldname, text)][1]
except KeyError:
raise TermNotFound("%s:%r" % (fieldname, text))
if self.segment.deleted and exclude_docs:
exclude_docs = self.segment.deleted | exclude_docs
elif self.segment.deleted:
exclude_docs = self.segment.deleted
postreader = FilePostingReader(self.postfile,
offset,
format,
scorer=scorer,
fieldname=fieldname,
text=text)
if exclude_docs:
postreader = ExcludeMatcher(postreader, exclude_docs)
return postreader
def vector(self, docnum, fieldname):
if fieldname not in self.schema:
raise TermNotFound("No field %r" % fieldname)
vformat = self.vector_format(fieldname)
if not vformat:
raise Exception("No vectors are stored for field %r" % fieldname)
self._open_vectors()
offset = self.vectorindex.get((docnum, fieldname))
if offset is None:
raise Exception("No vector found"
" for document %s field %r" % (docnum, fieldname))
return FilePostingReader(self.vpostfile,
offset,
vformat,
stringids=True)
class SegmentReader(IndexReader):
def __init__(self, storage, schema, segment, generation=None):
self.storage = storage
self.schema = schema
self.segment = segment
self._generation = generation
# Term index
tf = storage.open_file(segment.termsindex_filename)
self.termsindex = TermIndexReader(tf)
# Term postings file, vector index, and vector postings: lazy load
self.postfile = None
self.vectorindex = None
self.vpostfile = None
# Stored fields file
sf = storage.open_file(segment.storedfields_filename, mapped=False)
self.storedfields = StoredFieldReader(sf)
# Field length file
self.fieldlengths = None
if self.schema.has_scorable_fields():
flf = storage.open_file(segment.fieldlengths_filename)
self.fieldlengths = LengthReader(flf, segment.doc_count_all())
# Copy methods from underlying segment
self.has_deletions = segment.has_deletions
self.is_deleted = segment.is_deleted
self.doc_count = segment.doc_count
# Postings file
self.postfile = self.storage.open_file(segment.termposts_filename,
mapped=False)
self.dc = segment.doc_count_all()
assert self.dc == self.storedfields.length
self.is_closed = False
self._sync_lock = Lock()
def _open_vectors(self):
if self.vectorindex: return
storage, segment = self.storage, self.segment
# Vector index
vf = storage.open_file(segment.vectorindex_filename)
self.vectorindex = TermVectorReader(vf)
# Vector postings file
self.vpostfile = storage.open_file(segment.vectorposts_filename,
mapped=False)
def __repr__(self):
return "%s(%s)" % (self.__class__.__name__, self.segment)
@protected
def __contains__(self, term):
return term in self.termsindex
def generation(self):
return self._generation
def close(self):
self.storedfields.close()
self.termsindex.close()
if self.postfile:
self.postfile.close()
if self.vectorindex:
self.vectorindex.close()
#if self.fieldlengths:
# self.fieldlengths.close()
self.is_closed = True
def doc_count_all(self):
return self.dc
def field(self, fieldname):
return self.schema[fieldname]
def scorable(self, fieldname):
return self.schema[fieldname].scorable
def scorable_names(self):
return self.schema.scorable_names()
def vector_names(self):
return self.schema.vector_names()
def format(self, fieldname):
return self.schema[fieldname].format
def vector_format(self, fieldname):
return self.schema[fieldname].vector
@protected
def stored_fields(self, docnum):
schema = self.schema
return dict(item for item
in self.storedfields[docnum].iteritems()
if item[0] in schema)
@protected
def all_stored_fields(self):
is_deleted = self.segment.is_deleted
sf = self.stored_fields
for docnum in xrange(self.segment.doc_count_all()):
if not is_deleted(docnum):
yield sf(docnum)
def field_length(self, fieldname):
return self.segment.field_length(fieldname)
@protected
def doc_field_length(self, docnum, fieldname, default=0):
if self.fieldlengths is None: return default
return self.fieldlengths.get(docnum, fieldname, default=default)
def max_field_length(self, fieldname):
return self.segment.max_field_length(fieldname)
@protected
def has_vector(self, docnum, fieldname):
self._open_vectors()
return (docnum, fieldname) in self.vectorindex
@protected
def __iter__(self):
schema = self.schema
for (fieldname, t), (totalfreq, _, postcount) in self.termsindex:
if fieldname not in schema:
continue
yield (fieldname, t, postcount, totalfreq)
def _test_field(self, fieldname):
if fieldname not in self.schema:
raise TermNotFound("No field %r" % fieldname)
if self.schema[fieldname].format is None:
raise TermNotFound("Field %r is not indexed" % fieldname)
@protected
def iter_from(self, fieldname, text):
schema = self.schema
self._test_field(fieldname)
for (fn, t), (totalfreq, _, postcount) in self.termsindex.items_from((fieldname, text)):
if fn not in schema:
continue
yield (fn, t, postcount, totalfreq)
@protected
def _term_info(self, fieldname, text):
self._test_field(fieldname)
try:
return self.termsindex[(fieldname, text)]
except KeyError:
raise TermNotFound("%s:%r" % (fieldname, text))
def doc_frequency(self, fieldname, text):
self._test_field(fieldname)
try:
return self._term_info(fieldname, text)[2]
except TermNotFound:
return 0
def frequency(self, fieldname, text):
self._test_field(fieldname)
try:
return self._term_info(fieldname, text)[0]
except TermNotFound:
return 0
def lexicon(self, fieldname):
# The base class has a lexicon() implementation that uses iter_from()
# and throws away the value, but overriding to use
# FileTableReader.keys_from() is much, much faster.
self._test_field(fieldname)
return self.expand_prefix(fieldname, '')
@protected
def expand_prefix(self, fieldname, prefix):
# The base class has an expand_prefix() implementation that uses
# iter_from() and throws away the value, but overriding to use
# FileTableReader.keys_from() is much, much faster.
self._test_field(fieldname)
for fn, t in self.termsindex.keys_from((fieldname, prefix)):
if fn != fieldname or not t.startswith(prefix):
return
yield t
def postings(self, fieldname, text, exclude_docs=frozenset(), scorer=None):
self._test_field(fieldname)
format = self.format(fieldname)
try:
offset = self.termsindex[(fieldname, text)][1]
except KeyError:
raise TermNotFound("%s:%r" % (fieldname, text))
if self.segment.deleted and exclude_docs:
exclude_docs = self.segment.deleted | exclude_docs
elif self.segment.deleted:
exclude_docs = self.segment.deleted
postreader = FilePostingReader(self.postfile, offset, format,
scorer=scorer, fieldname=fieldname,
text=text)
if exclude_docs:
postreader = ExcludeMatcher(postreader, exclude_docs)
return postreader
def vector(self, docnum, fieldname):
if fieldname not in self.schema:
raise TermNotFound("No field %r" % fieldname)
vformat = self.vector_format(fieldname)
if not vformat:
raise Exception("No vectors are stored for field %r" % fieldname)
self._open_vectors()
offset = self.vectorindex.get((docnum, fieldname))
if offset is None:
raise Exception("No vector found"
" for document %s field %r" % (docnum, fieldname))
return FilePostingReader(self.vpostfile, offset, vformat, stringids=True)