Arksine 410db750c6 database: add annotations
Signed-off-by:  Eric Callahan <arksine.code@gmail.com>
2021-05-18 19:16:49 -04:00

492 lines
18 KiB
Python

# Mimimal database for moonraker storage
#
# Copyright (C) 2021 Eric Callahan <arksine.code@gmail.com>
#
# This file may be distributed under the terms of the GNU GPLv3 license.
from __future__ import annotations
import os
import json
import struct
import operator
import logging
from io import BytesIO
from functools import reduce
import lmdb
from utils import SentinelClass
# Annotation imports
from typing import (
TYPE_CHECKING,
Any,
ItemsView,
ValuesView,
Tuple,
Optional,
Union,
Dict,
List,
)
if TYPE_CHECKING:
from confighelper import ConfigHelper
from websockets import WebRequest
DBRecord = Union[int, float, bool, str, List[Any], Dict[str, Any]]
DBType = Optional[DBRecord]
DATABASE_VERSION = 1
MAX_NAMESPACES = 50
MAX_DB_SIZE = 200 * 2**20
RECORD_ENCODE_FUNCS = {
int: lambda x: b"q" + struct.pack("q", x),
float: lambda x: b"d" + struct.pack("d", x),
bool: lambda x: b"?" + struct.pack("?", x),
str: lambda x: b"s" + x.encode(),
list: lambda x: json.dumps(x).encode(),
dict: lambda x: json.dumps(x).encode(),
}
RECORD_DECODE_FUNCS = {
ord("q"): lambda x: struct.unpack("q", x[1:])[0],
ord("d"): lambda x: struct.unpack("d", x[1:])[0],
ord("?"): lambda x: struct.unpack("?", x[1:])[0],
ord("s"): lambda x: bytes(x[1:]).decode(),
ord("["): lambda x: json.load(BytesIO(x)),
ord("{"): lambda x: json.load(BytesIO(x)),
}
SENTINEL = SentinelClass.get_instance()
def getitem_with_default(item: Dict, field: Any) -> Any:
if field not in item:
item[field] = {}
return item[field]
class MoonrakerDatabase:
def __init__(self, config: ConfigHelper) -> None:
self.server = config.get_server()
self.namespaces: Dict[str, object] = {}
self.enable_debug = config.getboolean("enable_database_debug", False)
self.database_path = os.path.expanduser(config.get(
'database_path', "~/.moonraker_database"))
if not os.path.isdir(self.database_path):
os.mkdir(self.database_path)
self.lmdb_env = lmdb.open(self.database_path, map_size=MAX_DB_SIZE,
max_dbs=MAX_NAMESPACES)
with self.lmdb_env.begin(write=True, buffers=True) as txn:
# lookup existing namespaces
cursor = txn.cursor()
remaining = cursor.first()
while remaining:
key = bytes(cursor.key())
self.namespaces[key.decode()] = self.lmdb_env.open_db(key, txn)
remaining = cursor.next()
cursor.close()
if "moonraker" not in self.namespaces:
mrdb = self.lmdb_env.open_db(b"moonraker", txn)
self.namespaces["moonraker"] = mrdb
txn.put(b'database_version',
self._encode_value(DATABASE_VERSION),
db=mrdb)
# Protected Namespaces have read-only API access. Write access can
# be granted by enabling the debug option. Forbidden namespaces
# have no API access. This cannot be overridden.
self.protected_namespaces = set(self.get_item(
"moonraker", "database.protected_namespaces", ["moonraker"]))
self.forbidden_namespaces = set(self.get_item(
"moonraker", "database.forbidden_namespaces", []))
debug_counter: int = self.get_item(
"moonraker", "database.debug_counter", 0)
if self.enable_debug:
debug_counter += 1
self.insert_item("moonraker", "database.debug_counter",
debug_counter)
if debug_counter:
logging.info(f"Database Debug Count: {debug_counter}")
self.server.register_endpoint(
"/server/database/list", ['GET'], self._handle_list_request)
self.server.register_endpoint(
"/server/database/item", ["GET", "POST", "DELETE"],
self._handle_item_request)
def insert_item(self,
namespace: str,
key: Union[List[str], str],
value: DBType
) -> None:
key_list = self._process_key(key)
if namespace not in self.namespaces:
self.namespaces[namespace] = self.lmdb_env.open_db(
namespace.encode())
record = value
if len(key_list) > 1:
record = self._get_record(namespace, key_list[0], force=True)
if not isinstance(record, dict):
record = {}
logging.info(
f"Warning: Key {key_list[0]} contains a value of type "
f"{type(record)}. Overwriting with an object.")
item: Dict[str, Any] = reduce(getitem_with_default, key_list[1:-1],
record)
item[key_list[-1]] = value
if not self._insert_record(namespace, key_list[0], record):
logging.info(
f"Error inserting key '{key}' in namespace '{namespace}'")
def update_item(self,
namespace: str,
key: Union[List[str], str],
value: DBType
) -> None:
key_list = self._process_key(key)
record = self._get_record(namespace, key_list[0])
if len(key_list) == 1:
if isinstance(record, dict) and isinstance(value, dict):
record.update(value)
else:
assert value is not None
record = value
else:
try:
assert isinstance(record, dict)
item: Dict[str, Any] = reduce(
operator.getitem, key_list[1:-1], record)
except Exception:
raise self.server.error(
f"Key '{key}' in namespace '{namespace}' not found", 404)
if isinstance(item[key_list[-1]], dict) \
and isinstance(value, dict):
item[key_list[-1]].update(value)
else:
item[key_list[-1]] = value
if not self._insert_record(namespace, key_list[0], record):
logging.info(
f"Error updating key '{key}' in namespace '{namespace}'")
def delete_item(self,
namespace: str,
key: Union[List[str], str],
drop_empty_db: bool = False
) -> Any:
key_list = self._process_key(key)
val = record = self._get_record(namespace, key_list[0])
remove_record = True
if len(key_list) > 1:
try:
assert isinstance(record, dict)
item: Dict[str, Any] = reduce(
operator.getitem, key_list[1:-1], record)
val = item.pop(key_list[-1])
except Exception:
raise self.server.error(
f"Key '{key}' in namespace '{namespace}' not found", 404)
remove_record = False if record else True
if remove_record:
db = self.namespaces[namespace]
with self.lmdb_env.begin(write=True, buffers=True, db=db) as txn:
ret = txn.delete(key_list[0].encode())
cursor = txn.cursor()
if not cursor.first() and drop_empty_db:
txn.drop(db)
del self.namespaces[namespace]
else:
ret = self._insert_record(namespace, key_list[0], record)
if not ret:
logging.info(
f"Error deleting key '{key}' from namespace '{namespace}'")
return val
def get_item(self,
namespace: str,
key: Optional[Union[List[str], str]] = None,
default: Any = SENTINEL
) -> Any:
try:
if key is None:
return self._get_namespace(namespace)
key_list = self._process_key(key)
ns = self._get_record(namespace, key_list[0])
val = reduce(operator.getitem, key_list[1:], ns) # type: ignore
except Exception:
if not isinstance(default, SentinelClass):
return default
raise self.server.error(
f"Key '{key}' in namespace '{namespace}' not found", 404)
return val
def ns_length(self, namespace: str) -> int:
return len(self.ns_keys(namespace))
def ns_keys(self, namespace: str) -> List[str]:
keys: List[str] = []
db = self.namespaces[namespace]
with self.lmdb_env.begin(db=db) as txn:
cursor = txn.cursor()
remaining = cursor.first()
while remaining:
keys.append(cursor.key().decode())
remaining = cursor.next()
return keys
def ns_values(self, namespace: str) -> ValuesView:
ns = self._get_namespace(namespace)
return ns.values()
def ns_items(self, namespace: str) -> ItemsView:
ns = self._get_namespace(namespace)
return ns.items()
def ns_contains(self, namespace: str, key: Union[List[str], str]) -> bool:
try:
key_list = self._process_key(key)
if len(key_list) == 1:
return key_list[0] in self.ns_keys(namespace)
ns = self._get_namespace(namespace)
reduce(operator.getitem, key_list[1:], ns)
except Exception:
return False
return True
def register_local_namespace(self,
namespace: str,
forbidden: bool = False
) -> None:
if namespace not in self.namespaces:
self.namespaces[namespace] = self.lmdb_env.open_db(
namespace.encode())
if forbidden:
if namespace not in self.forbidden_namespaces:
self.forbidden_namespaces.add(namespace)
self.insert_item(
"moonraker", "database.forbidden_namespaces",
list(self.forbidden_namespaces))
elif namespace not in self.protected_namespaces:
self.protected_namespaces.add(namespace)
self.insert_item("moonraker", "database.protected_namespaces",
list(self.protected_namespaces))
def wrap_namespace(self,
namespace: str,
parse_keys: bool = True
) -> NamespaceWrapper:
if namespace not in self.namespaces:
raise self.server.error(
f"Namespace '{namespace}' not found", 404)
return NamespaceWrapper(namespace, self, parse_keys)
def _process_key(self, key: Union[List[str], str]) -> List[str]:
try:
key_list = key if isinstance(key, list) else key.split('.')
except Exception:
key_list = []
if not key_list or "" in key_list:
raise self.server.error(f"Invalid Key Format: '{key}'")
return key_list
def _insert_record(self, namespace: str, key: str, val: DBType) -> bool:
db = self.namespaces[namespace]
if val is None:
return False
with self.lmdb_env.begin(write=True, buffers=True, db=db) as txn:
ret = txn.put(key.encode(), self._encode_value(val))
return ret
def _get_record(self,
namespace: str,
key: str,
force: bool = False
) -> DBRecord:
if namespace not in self.namespaces:
raise self.server.error(
f"Namespace '{namespace}' not found", 404)
db = self.namespaces[namespace]
with self.lmdb_env.begin(buffers=True, db=db) as txn:
value = txn.get(key.encode())
if value is None:
if force:
return {}
raise self.server.error(
f"Key '{key}' in namespace '{namespace}' not found", 404)
return self._decode_value(value)
def _get_namespace(self, namespace: str) -> Dict[str, Any]:
if namespace not in self.namespaces:
raise self.server.error(
f"Invalid database namespace '{namespace}'")
db = self.namespaces[namespace]
result = {}
with self.lmdb_env.begin(buffers=True, db=db) as txn:
cursor = txn.cursor()
cursor.first()
for db_key, value in cursor:
k = bytes(db_key).decode()
result[k] = self._decode_value(value)
return result
def _encode_value(self, value: DBRecord) -> bytes:
try:
enc_func = RECORD_ENCODE_FUNCS[type(value)]
return enc_func(value)
except Exception:
raise self.server.error(
f"Error encoding val: {value}, type: {type(value)}")
def _decode_value(self, bvalue: bytes) -> DBRecord:
fmt = bvalue[0]
try:
decode_func = RECORD_DECODE_FUNCS[fmt]
return decode_func(bvalue)
except Exception:
raise self.server.error(
f"Error decoding value {bvalue.decode()}, format: {chr(fmt)}")
async def _handle_list_request(self,
web_request: WebRequest
) -> Dict[str, List[str]]:
ns_list = set(self.namespaces.keys()) - self.forbidden_namespaces
return {'namespaces': list(ns_list)}
async def _handle_item_request(self,
web_request: WebRequest
) -> Dict[str, Any]:
action = web_request.get_action()
namespace = web_request.get_str("namespace")
if namespace in self.forbidden_namespaces:
raise self.server.error(
f"Read/Write access to namespace '{namespace}'"
" is forbidden", 403)
key: Any
valid_types: Tuple[type, ...]
if action != "GET":
if namespace in self.protected_namespaces and \
not self.enable_debug:
raise self.server.error(
f"Write access to namespaces '{namespace}'"
" is forbidden", 403)
key = web_request.get("key")
valid_types = (list, str)
else:
key = web_request.get("key", None)
valid_types = (list, str, type(None))
if not isinstance(key, valid_types):
raise self.server.error(
"Value for argument 'key' is an invalid type: "
f"{type(key).__name__}")
if action == "GET":
val = self.get_item(namespace, key)
elif action == "POST":
val = web_request.get("value")
self.insert_item(namespace, key, val)
elif action == "DELETE":
val = self.delete_item(namespace, key, drop_empty_db=True)
return {'namespace': namespace, 'key': key, 'value': val}
def close(self) -> None:
# log db stats
msg = ""
with self.lmdb_env.begin() as txn:
for db_name, db in self.namespaces.items():
stats = txn.stat(db)
msg += f"\n{db_name}:\n"
msg += "\n".join([f"{k}: {v}" for k, v in stats.items()])
logging.info(f"Database statistics:\n{msg}")
self.lmdb_env.sync()
self.lmdb_env.close()
class NamespaceWrapper:
def __init__(self,
namespace: str,
database: MoonrakerDatabase,
parse_keys: bool
) -> None:
self.namespace = namespace
self.db = database
# If parse keys is true, keys of a string type
# will be passed straight to the DB methods.
self.parse_keys = parse_keys
def insert(self, key: Union[List[str], str], value: DBType) -> None:
if isinstance(key, str) and not self.parse_keys:
key = [key]
self.db.insert_item(self.namespace, key, value)
def update_child(self, key: Union[List[str], str], value: DBType) -> None:
if isinstance(key, str) and not self.parse_keys:
key = [key]
self.db.update_item(self.namespace, key, value)
def update(self, value: Dict[str, Any]) -> None:
val_keys = set(value.keys())
new_keys = val_keys - set(self.keys())
update_keys = val_keys - new_keys
for key in update_keys:
self.update_child([key], value[key])
for key in new_keys:
self.insert([key], value[key])
def get(self,
key: Union[List[str], str],
default: Any = None
) -> Any:
if isinstance(key, str) and not self.parse_keys:
key = [key]
return self.db.get_item(self.namespace, key, default)
def delete(self, key: Union[List[str], str]) -> Any:
if isinstance(key, str) and not self.parse_keys:
key = [key]
return self.db.delete_item(self.namespace, key)
def __len__(self) -> int:
return self.db.ns_length(self.namespace)
def __getitem__(self, key: Union[List[str], str]) -> Any:
return self.get(key, default=SENTINEL)
def __setitem__(self,
key: Union[List[str], str],
value: DBType
) -> None:
self.insert(key, value)
def __delitem__(self, key: Union[List[str], str]):
self.delete(key)
def __contains__(self, key: Union[List[str], str]) -> bool:
if isinstance(key, str) and not self.parse_keys:
key = [key]
return self.db.ns_contains(self.namespace, key)
def keys(self) -> List[str]:
return self.db.ns_keys(self.namespace)
def values(self) -> ValuesView:
return self.db.ns_values(self.namespace)
def items(self) -> ItemsView:
return self.db.ns_items(self.namespace)
def pop(self,
key: Union[List[str], str],
default: Any = SENTINEL
) -> Any:
try:
val = self.delete(key)
except Exception:
if isinstance(default, SentinelClass):
raise
val = default
return val
def clear(self) -> None:
keys = self.keys()
for k in keys:
try:
self.delete([k])
except Exception:
pass
def load_component(config: ConfigHelper) -> MoonrakerDatabase:
return MoonrakerDatabase(config)