def update_document(self, **fields):
self._check_state()
_unique_cache = self._unique_cache
# Check which of the supplied fields are unique
unique_fields = [
name for name, field in self.schema.items()
if name in fields and field.unique
]
if not unique_fields:
raise IndexingError("None of the fields in %r"
" are unique" % fields.keys())
# Delete documents matching the unique terms
delset = set()
for name in unique_fields:
field = self.schema[name]
text = field.to_text(fields[name])
# If we've seen an update_document with this unique field before...
if name in _unique_cache:
# Get the cache for this field
term2docnum = _unique_cache[name]
# If the cache is None, that means we've seen this field once
# before but didn't cache it the first time. Cache it now.
if term2docnum is None:
# Read the first document number found for every term in
# this field and cache the mapping from term to doc num
term2docnum = {}
s = self.searcher()
term2docnum = dict(s.first_ids(name))
s.close()
_unique_cache[name] = term2docnum
# Look up the cached document number for this term
if text in term2docnum:
delset.add(term2docnum[text])
else:
# This is the first time we've seen an update_document with
# this field. Mark it by putting None in the cache for this
# field, but don't cache it. We'll only build the cache if we
# see an update_document on this field again. This is to
# prevent caching a field even when the user is only going to
# call update_document once.
reader = self.searcher().reader()
try:
delset.add(reader.postings(name, text).id())
_unique_cache[name] = None
except TermNotFound:
pass
finally:
reader.close()
# Delete the old docs
for docnum in delset:
self.delete_document(docnum)
# Add the given fields
self.add_document(**fields)
def delete_document(self, docnum, delete=True):
self._check_state()
if docnum >= sum(seg.doccount for seg in self.segments):
raise IndexingError("No document ID %r in this index" % docnum)
segment, segdocnum = self._segment_and_docnum(docnum)
segment.delete_document(segdocnum, delete=delete)
def _check_state(self):
if self.is_closed:
raise IndexingError("This writer is closed")