def __init__(self, name, create=False, analyzer=None):
# XXX FIXME: we should really try opening the db here, so that
# any errors are caught immediately rather than waiting for the
# first time we try to do something...
ReadOnlyIndex.__init__(self, name)
self.name = name
if create:
self.flags = xapian.DB_CREATE_OR_OPEN
else:
self.flags = xapian.DB_OPEN
self.analyzer = analyzer or StandardAnalyzer()
self.lockFile = FilesystemLock(os.path.join(self.name, XAPWRAP_LOCK_FILENAME))
class Index(ReadOnlyIndex):
def __init__(self, name, create=False, analyzer=None):
# XXX FIXME: we should really try opening the db here, so that
# any errors are caught immediately rather than waiting for the
# first time we try to do something...
ReadOnlyIndex.__init__(self, name)
self.name = name
if create:
self.flags = xapian.DB_CREATE_OR_OPEN
else:
self.flags = xapian.DB_OPEN
self.analyzer = analyzer or StandardAnalyzer()
self.lockFile = FilesystemLock(os.path.join(self.name, XAPWRAP_LOCK_FILENAME))
def _setupDB(self):
""" really get a xapian database object """
# xapian expects directories! self.name should refer to a
# directory. if it doesn't exist, we'll make one.
if not os.path.exists(self.name):
os.mkdir(self.name)
# try to acquire a lock file
if not self.lockFile.lock():
owningPid = os.readlink(self.lockFile.name)
errorMsg = "cannot acquire lock file for xapian index %s" "because it is owned by process %s" % (
self.name,
owningPid,
)
log(errorMsg)
raise DatabaseLockError(errorMsg)
xapLockFilePath = os.path.join(self.name, XAPIAN_LOCK_FILENAME)
if os.path.exists(xapLockFilePath):
log("Stale database lock found in %s. Deleting it now." % xapLockFilePath)
os.remove(xapLockFilePath)
# actually try to open a xapian DB
try:
try:
self.db = ExceptionTranslater.openIndex(False, self.name, self.flags)
except DatabaseCorruptionError, e:
# the index is trashed, so there's no harm in blowing it
# away and starting from scratch
log("Xapian index at %s is corrupted and will be destroyed" % self.name)
if self.lockFile.locked:
self.lockFile.unlock()
for idxFname in glob.glob(os.path.join(self.name, "*")):
os.remove(idxFname)
self.db = ExceptionTranslater.openIndex(False, self.name, self.flags)
finally:
if self.db is None and self.lockFile.locked:
self.lockFile.unlock()
def __del__(self):
self.close()
def close(self):
# this is important! the only way to get xapian to release the
# db lock is to call the db object's destructor. that won't
# happen until nobody is holding a reference to the db
# object. unfortunately, the query parser holds a reference to
# it, so the query parser must also go away. do not hold
# references to these objects anywhere but here.
# enquire objects and mset objects hold a reference to the db,
# so if any of them are left alive, the db will not be reclaimed
if self.db is not None:
ReadOnlyIndex.close(self)
# the islink test is needed in case the index directory has
# been deleted before we close was called.
if self.lockFile.locked and os.path.islink(self.lockFile.name):
self.lockFile.unlock()
# there is no point in checking if the lock file is still
# around right here: it will only be deleted when xapian's
# destructor runs, but python defers running destructors
# until after exception handling is complete. since this
# code will often get called from an exception handler, we
# have to assume that the lock file's removal will be
# delayed at least until after this method exits
def get_document(self, uid):
return self._get_document(uid)
# methods that modify db state
def index(self, doc):
self.setupDB()
if hasattr(doc, "uid") and doc.uid:
uid = int(doc.uid)
doc.sortFields.append(SortKey("uid", uid))
doc.keywords.append(Keyword("uid", str(uid)))
xapDoc = doc.toXapianDocument(self.indexValueMap, self.prefixMap)
self.replace_document(uid, xapDoc)
else:
# We need to know the uid of the doc we're going to add
# before we add it so we can setup appropriate uid sorting
# values. But, another thread could potentially insert a
# document at that uid after we determine the last uid, but
# before we manage the insertion. Yay race conditions! So we
# try to add the document and then check that it ended up at
# the right uid. If it did not, we update it with the
# correct uid sort values.
uid = self.get_lastdocid() + 1
doc.sortFields.append(SortKey("uid", uid))
doc.keywords.append(Keyword("uid", str(uid)))
xapDoc = doc.toXapianDocument(self.indexValueMap, self.prefixMap)
newUID = self.add_document(xapDoc)
if newUID != uid:
doc.sortFields.append(SortKey("uid", newUID))
doc.keywords.append(Keyword("uid", str(newUID)))
xapDoc = doc.toXapianDocument(self.indexValueMap, self.prefixMap)
self.replace_document(newUID, xapDoc)
# a simpler alternative would be to add an empty document
# and then replace it. the problem with that strategy is
# that it kills performance since xapian performs an
# implicit flush when you replace a document that was added
# but not yet committed to disk.
self.amountIndexedSinceLastFlush += len(doc)
if self.amountIndexedSinceLastFlush > MAX_DATA_INDEXED_BETWEEN_FLUSHES:
self.flush()
return uid
def add_document(self, doc):
return self.db.add_document(doc)
add_document = makeProtectedDBMethod(add_document)
def replace_document(self, uid, doc):
return self.db.replace_document(uid, doc)
replace_document = makeProtectedDBMethod(replace_document)
def delete_document(self, docID):
return self.db.delete_document(docID)
delete_document = makeProtectedDBMethod(delete_document)