python-oracledb/src/oracledb/impl/thin/connection.pyx

425 lines
17 KiB
Cython

#------------------------------------------------------------------------------
# Copyright (c) 2020, 2023, Oracle and/or its affiliates.
#
# This software is dual-licensed to you under the Universal Permissive License
# (UPL) 1.0 as shown at https://oss.oracle.com/licenses/upl and Apache License
# 2.0 as shown at http://www.apache.org/licenses/LICENSE-2.0. You may choose
# either license.
#
# If you elect to accept the software under the Apache License, Version 2.0,
# the following applies:
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# https://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#------------------------------------------------------------------------------
#------------------------------------------------------------------------------
# connection.pyx
#
# Cython file defining the thin Connection implementation class (embedded in
# thin_impl.pyx).
#------------------------------------------------------------------------------
cdef class ThinConnImpl(BaseConnImpl):
cdef:
object _statement_cache
uint32_t _statement_cache_size
object _statement_cache_lock
Protocol _protocol
str _server_version
uint32_t _session_id
uint32_t _serial_num
str _action
bint _action_modified
str _dbop
bint _dbop_modified
str _client_info
bint _client_info_modified
str _client_identifier
bint _client_identifier_modified
str _module
bint _module_modified
ThinPoolImpl _pool
bytes _ltxid
str _current_schema
bint _current_schema_modified
str _edition
str _internal_name
str _external_name
array.array _cursors_to_close
ssize_t _num_cursors_to_close
bint _drcp_enabled
bint _drcp_establish_session
double _time_in_pool
list _temp_lobs_to_close
uint32_t _temp_lobs_total_size
uint32_t _call_timeout
str _cclass
int _dbobject_type_cache_num
bytes _combo_key
str _connection_id
bint _is_pool_extra
def __init__(self, str dsn, ConnectParamsImpl params):
if not HAS_CRYPTOGRAPHY:
errors._raise_err(errors.ERR_NO_CRYPTOGRAPHY_PACKAGE)
BaseConnImpl.__init__(self, dsn, params)
self._protocol = Protocol()
cdef int _add_cursor_to_close(self, Statement stmt) except -1:
if self._num_cursors_to_close == TNS_MAX_CURSORS_TO_CLOSE:
errors._raise_err(errors.ERR_TOO_MANY_CURSORS_TO_CLOSE,
num_cursors=TNS_MAX_CURSORS_TO_CLOSE)
self._cursors_to_close[self._num_cursors_to_close] = stmt._cursor_id
self._num_cursors_to_close += 1
cdef int _adjust_statement_cache(self) except -1:
cdef Statement stmt
while len(self._statement_cache) > self._statement_cache_size:
stmt = <Statement> self._statement_cache.popitem(last=False)[1]
if stmt._in_use:
stmt._return_to_cache = False
elif stmt._cursor_id != 0:
self._add_cursor_to_close(stmt)
cdef int _connect_with_address(self, Address address,
Description description,
ConnectParamsImpl params,
str connect_string,
bint raise_exception) except -1:
"""
Internal method used for connecting with the given description and
address.
"""
cdef ConnectionCookie cookie
try:
cookie = self._protocol._connect_phase_one(self, params,
description, address,
connect_string)
except (exceptions.DatabaseError, socket.gaierror,
ConnectionRefusedError) as e:
if raise_exception:
errors._raise_err(errors.ERR_CONNECTION_FAILED, cause=e,
connection_id=description.connection_id)
return 0
except Exception as e:
errors._raise_err(errors.ERR_CONNECTION_FAILED, cause=e,
connection_id=description.connection_id)
self._drcp_enabled = description.server_type == "pooled"
if self._cclass is None:
self._cclass = description.cclass
if self._cclass is None and self._pool is not None \
and self._drcp_enabled:
gen_uuid = uuid.uuid4()
self._cclass = f"DPY:{base64.b64encode(gen_uuid.bytes).decode()}"
params._default_description.cclass = self._cclass
self._protocol._connect_phase_two(self, cookie, description, params)
cdef int _connect_with_description(self, Description description,
ConnectParamsImpl params,
bint final_desc) except -1:
"""
Internal method used for connecting with the given description.
"""
cdef:
bint load_balance = description.load_balance
bint raise_exc = False
list address_lists = description.address_lists
uint32_t i, j, k, num_addresses, idx1, idx2
uint32_t num_attempts = description.retry_count + 1
uint32_t num_lists = len(address_lists)
AddressList address_list
str connect_string
Address address
# Retry connecting to the socket if an attempt fails and retry_count
# is specified in the connect string. If an attempt succeeds, return
# the socket and the valid address object.
connect_string = _get_connect_data(description, self._connection_id)
for i in range(num_attempts):
# iterate through each address_list in the description; if the
# description level load_balance is on, keep track of the least
# recently used address for subsequent connections; otherwise,
# iterate through the list in order; note that if source_route is
# enabled that only the first address list is examined as the rest
# are used for routing on the server
if description.source_route and num_lists > 0:
num_lists = 1
for j in range(num_lists):
if load_balance:
idx1 = (j + description.lru_index) % num_lists
else:
idx1 = j
# iterate through each address in an address_list; if the
# address_list level load_balance is on, keep track of the
# least recently used address for subsequent connections;
# otherwise, iterate through the list in order; note that if
# source_route is enabled that only the first address is
# examined and the rest are used for routing on the server
address_list = address_lists[idx1]
num_addresses = len(address_list.addresses)
if address_list.source_route and num_addresses > 0:
num_addresses = 1
for k in range(num_addresses):
if address_list.load_balance:
idx2 = (k + address_list.lru_index) % num_addresses
else:
idx2 = k
address = address_list.addresses[idx2]
if final_desc:
raise_exc = i == num_attempts - 1 \
and j == num_lists - 1 \
and k == num_addresses - 1
self._connect_with_address(address, description, params,
connect_string, raise_exc)
if self._protocol._in_connect:
continue
address_list.lru_index = (idx1 + 1) % num_addresses
description.lru_index = (idx2 + 1) % num_lists
return 0
time.sleep(description.retry_delay)
cdef int _connect_with_params(self, ConnectParamsImpl params) except -1:
"""
Internal method used for connecting with the given parameters.
"""
cdef:
DescriptionList description_list = params.description_list
list descriptions = description_list.descriptions
ssize_t i, idx, num_descriptions = len(descriptions)
Description description
bint final_desc = False
if description_list.source_route and num_descriptions > 0:
num_descriptions = 1
for i in range(num_descriptions):
if i == num_descriptions - 1:
final_desc = True
if description_list.load_balance:
idx = (i + description_list.lru_index) % num_descriptions
else:
idx = i
description = descriptions[idx]
self._connect_with_description(description, params, final_desc)
if not self._protocol._in_connect:
description_list.lru_index = (idx + 1) % num_descriptions
break
cdef Message _create_message(self, type typ):
"""
Creates a message object that is used to send a request to the database
and receive back its response.
"""
cdef Message message
message = typ.__new__(typ)
message._initialize(self)
return message
cdef int _force_close(self) except -1:
self._pool = None
if self._dbobject_type_cache_num > 0:
remove_dbobject_type_cache(self._dbobject_type_cache_num)
self._dbobject_type_cache_num = 0
self._protocol._force_close()
cdef Statement _get_statement(self, str sql, bint cache_statement):
"""
Get a statement from the statement cache, or prepare a new statement
for use. If a statement is already in use a copy will be made and
returned (and will not be returned to the cache). If a statement is
being executed for the first time after releasing a DRCP session, a
copy will also be made (and will not be returned to the cache) since it
is unknown at this point whether the original session or a new session
is going to be used.
"""
cdef Statement statement
with self._statement_cache_lock:
statement = self._statement_cache.get(sql)
if statement is None:
statement = Statement()
statement._prepare(sql)
if cache_statement and not self._drcp_establish_session \
and not statement._is_ddl \
and self._statement_cache_size > 0:
statement._return_to_cache = True
self._statement_cache[sql] = statement
self._adjust_statement_cache()
elif statement._in_use or not cache_statement \
or self._drcp_establish_session:
if not cache_statement:
del self._statement_cache[sql]
statement._return_to_cache = False
if statement._in_use or self._drcp_establish_session:
statement = statement.copy()
else:
self._statement_cache.move_to_end(sql)
statement._in_use = True
return statement
cdef int _reset_statement_cache(self) except -1:
"""
Reset the statement cache. This clears all statements and the list of
cursors that need to be cleared.
"""
with self._statement_cache_lock:
self._statement_cache.clear()
self._num_cursors_to_close = 0
cdef int _return_statement(self, Statement statement) except -1:
"""
Return the statement to the statement cache, if applicable. If the
statement must not be returned to the statement cache, add the cursor
id to the list of cursor ids to close on the next round trip to the
database. Clear all bind variables and fetch variables in order to
ensure that unnecessary references are not retained.
"""
cdef:
ThinVarImpl var_impl
BindInfo bind_info
if statement._bind_info_list is not None:
for bind_info in statement._bind_info_list:
bind_info._bind_var_impl = None
if statement._fetch_var_impls is not None:
for var_impl in statement._fetch_var_impls:
var_impl._values = [None] * var_impl.num_elements
with self._statement_cache_lock:
if statement._return_to_cache:
statement._in_use = False
elif statement._cursor_id != 0:
self._add_cursor_to_close(statement)
def cancel(self):
self._protocol._break_external()
def change_password(self, str old_password, str new_password):
cdef ChangePasswordMessage message
message = self._create_message(ChangePasswordMessage)
message.password = old_password.encode()
message.newpassword = new_password.encode()
self._protocol._process_single_message(message)
def close(self, bint in_del=False):
try:
self._protocol._close(self)
except (ssl.SSLError, exceptions.DatabaseError):
pass
def commit(self):
cdef Message message
message = self._create_message(CommitMessage)
self._protocol._process_single_message(message)
def connect(self, ConnectParamsImpl params):
params._check_credentials()
self._connection_id = base64.b64encode(secrets.token_bytes(16)).decode()
self._connect_with_params(params)
self._statement_cache = collections.OrderedDict()
self._statement_cache_size = params.stmtcachesize
self._statement_cache_lock = threading.Lock()
self._dbobject_type_cache_num = create_new_dbobject_type_cache(self)
self._cursors_to_close = array.array('I')
array.resize(self._cursors_to_close, TNS_MAX_CURSORS_TO_CLOSE)
self.invoke_session_callback = True
def create_cursor_impl(self):
return ThinCursorImpl.__new__(ThinCursorImpl, self)
def create_temp_lob_impl(self, DbType dbtype):
return ThinLobImpl._create(self, dbtype)
def get_call_timeout(self):
return self._call_timeout
def get_current_schema(self):
return self._current_schema
def get_edition(self):
return self._edition
def get_external_name(self):
return self._external_name
def get_internal_name(self):
return self._internal_name
def get_is_healthy(self):
return self._protocol._socket is not None \
and not self._protocol._read_buf._session_needs_to_be_closed
def get_ltxid(self):
return self._ltxid or b''
def get_stmt_cache_size(self):
return self._statement_cache_size
def get_type(self, object conn, str name):
cdef ThinDbObjectTypeCache cache = \
get_dbobject_type_cache(self._dbobject_type_cache_num)
return cache.get_type(conn, name)
def get_version(self):
return self._server_version
def ping(self):
cdef Message message
message = self._create_message(PingMessage)
self._protocol._process_single_message(message)
def rollback(self):
cdef Message message
message = self._create_message(RollbackMessage)
self._protocol._process_single_message(message)
def set_action(self, str value):
self._action = value
self._action_modified = True
def set_call_timeout(self, uint32_t value):
timeout = None if value == 0 else value / 1000
self._protocol._socket.settimeout(timeout)
self._call_timeout = value
def set_client_identifier(self, str value):
self._client_identifier = value
self._client_identifier_modified = True
def set_client_info(self, str value):
self._client_info = value
self._client_info_modified = True
def set_current_schema(self, value):
self._current_schema = value
self._current_schema_modified = True
def set_dbop(self, str value):
self._dbop = value
self._dbop_modified = True
def set_external_name(self, value):
self._external_name = value
def set_internal_name(self, value):
self._internal_name = value
def set_module(self, str value):
self._module = value
self._module_modified = True
# setting the module by itself results in an error so always force the
# action to be set as well (which eliminates this error)
self._action_modified = True
def set_stmt_cache_size(self, uint32_t value):
self._statement_cache_size = value
self._adjust_statement_cache()