def _get_item(self, value_key: str, local_db: Shelf) -> Optional[Any]:
version_key = f"{value_key}_{constants.DB_ITEM_VERSION_SUFFIX}"
default_version = Version("0.0.0")
current_version = self._current_versions[version_key]
actual_version = (checked_cast(Version, local_db[version_key])
if version_key in local_db else default_version)
return local_db.get(
value_key) if actual_version >= current_version else None
class ShelfDatabase(database.Database):
"""ShelfDatabase is a thread-safe implementation of the
journal.database.Database interface which uses python Shelve for the
underlying persistence.
Attributes:
lock (threading.RLock): A reentrant lock to ensure threadsafe access.
shelf (shelve.Shelf): The underlying shelf database.
"""
def __init__(self, filename, flag):
"""Constructor for the ShelfDatabase class.
Args:
filename (str): The filename of the database file.
flag (str): a flag indicating the mode for opening the database.
Refer to the documentation for anydbm.open().
"""
super(ShelfDatabase, self).__init__()
self._lock = RLock()
self._shelf = Shelf(anydbm.open(filename, flag))
def __len__(self):
with self._lock:
return len(self._shelf)
def __contains__(self, key):
with self._lock:
return key in self._shelf
def get(self, key):
"""Retrieves a value associated with a key from the database
Args:
key (str): The key to retrieve
"""
with self._lock:
return self._shelf.get(key, default=None)
def set(self, key, value):
"""Sets a value associated with a key in the database
Args:
key (str): The key to set.
value (str): The value to associate with the key.
"""
with self._lock:
self._shelf[key] = value
def delete(self, key):
"""Removes a key:value from the database
Args:
key (str): The key to remove.
"""
with self._lock:
del self._shelf[key]
def sync(self):
"""Ensures that pending writes are flushed to disk
"""
with self._lock:
self._shelf.sync()
def close(self):
"""Closes the connection to the database
"""
with self._lock:
self._shelf.close()
def keys(self):
"""Returns a list of keys in the database
"""
with self._lock:
return self._shelf.keys()
def get(self, key, default=None):
with self._lock:
return Shelf.get(self, key, default)
class ShelfDatabase(database.Database):
"""ShelfDatabase is a thread-safe implementation of the
sawtooth_validator.database.Database interface which uses python Shelve
for the underlying persistence.
Attributes:
lock (threading.RLock): A reentrant lock to ensure threadsafe access.
shelf (shelve.Shelf): The underlying shelf database.
"""
def __init__(self, filename, flag):
"""Constructor for the ShelfDatabase class.
Args:
filename (str): The filename of the database file.
flag (str): a flag indicating the mode for opening the database.
Refer to the documentation for anydbm.open().
"""
super(ShelfDatabase, self).__init__()
self._lock = RLock()
self._shelf = Shelf(dbm.open(filename, flag))
def __len__(self):
with self._lock:
return len(self._shelf)
def __contains__(self, key):
with self._lock:
return key in self._shelf
def get(self, key):
"""Retrieves a value associated with a key from the database
Args:
key (str): The key to retrieve
"""
with self._lock:
return self._shelf.get(key, default=None)
def set(self, key, value):
"""Sets a value associated with a key in the database
Args:
key (str): The key to set.
value (str): The value to associate with the key.
"""
with self._lock:
self._shelf[key] = value
def delete(self, key):
"""Removes a key:value from the database
Args:
key (str): The key to remove.
"""
with self._lock:
del self._shelf[key]
def sync(self):
"""Ensures that pending writes are flushed to disk
"""
with self._lock:
self._shelf.sync()
def close(self):
"""Closes the connection to the database
"""
with self._lock:
self._shelf.close()
def keys(self):
"""Returns a list of keys in the database
"""
with self._lock:
return self._shelf.keys()
def get(self, key, default=None):
with self._lock:
return Shelf.get(self, key, default)