在OrientDB pyorient 的使用中发现，如果因为执行非法的语句（比如 select * from xxxxxxxx, xxxxxxxx 是一个不存在的class）导致OrientDB Server 解析失败（com.orientechnologies.orient.core.exception.OQueryParsingException: Error on parsing query), pyorient 会抛出 MemoryError。 此时pyorient client 就不能正常使用，会“阻塞”当前进程，需要重新初始化client 才可以继续使用。
具体示例如下：
# filename: test.py
import logging
from tornado.options import parse_command_line
import pyorient
cmdb_port = 2424
cmdb_url = "db-vip"
db_username = "root"
db_password = "root"
db_name = "cmdb_test"
client = pyorient.OrientDB(cmdb_url, cmdb_port)
session_id = client.connect(db_username, db_password)
def test_cmd(sql_cmd):
logging.info('come into test_cmd')
try:
client.db_open(db_name, db_username, db_password)
ret = client.command(sql_cmd)
logging.info('ret len: %s', len(ret))
except Exception as e:
logging.exception("Test cmd failed, Exception: %s", e.args)
if __name__ == '__main__':
parse_command_line()
sql_cmd_1 = 'select * from xxxxxxx' # 类 xxxxxxx 不存在，非法的sql 语句
for i in range(3):
test_cmd(sql_cmd_1)
sql_cmd_2 = 'select * from V' # 有效的sql 语句
test_cmd(sql_cmd_2)
执行 test.py 文件, 发现：
三次执行 sql_cmd_1 都出现了异常，提示 MemoryError.
之后执行 sql_cmd_2 也出现了同样的异常，提示 MemoryError.
(py2.7.13env) [root@test-app-1 misc]# python test.py
[I 180322 15:56:20 test:19] come into test_cmd
[E 180322 15:56:20 test:30] Test cmd failed, Exception: ()
Traceback (most recent call last):
File "test.py", line 22, in test_cmd
ret = client.command(sql_cmd)
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/orient.py", line 462, in command
.prepare(( QUERY_CMD, ) + args).send().fetch_response()
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/messages/commands.py", line 144, in fetch_response
super( CommandMessage, self ).fetch_response()
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/messages/base.py", line 265, in fetch_response
self._decode_all()
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/messages/base.py", line 249, in _decode_all
self._decode_header()
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/messages/base.py", line 176, in _decode_header
serialized_exception = self._decode_field( FIELD_STRING )
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/messages/base.py", line 366, in _decode_field
_decoded_string = self._orientSocket.read( _len )
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/orient.py", line 164, in read
buf = bytearray(_len_to_read)
MemoryError
[I 180322 15:56:20 test:19] come into test_cmd
[E 180322 15:56:20 test:30] Test cmd failed, Exception: ()
Traceback (most recent call last):
File "test.py", line 21, in test_cmd
client.db_open(db_name, db_username, db_password)
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/orient.py", line 412, in db_open
.prepare((db_name, user, password, db_type, client_id)).send().fetch_response()
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/messages/database.py", line 101, in fetch_response
result = super(DbOpenMessage, self).fetch_response()
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/messages/base.py", line 265, in fetch_response
self._decode_all()
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/messages/base.py", line 250, in _decode_all
self._decode_body()
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/messages/base.py", line 242, in _decode_body
self._body.append( self._decode_field( field ) )
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/messages/base.py", line 366, in _decode_field
_decoded_string = self._orientSocket.read( _len )
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/orient.py", line 164, in read
buf = bytearray(_len_to_read)
MemoryError
[I 180322 15:56:20 test:19] come into test_cmd
[E 180322 15:56:20 test:30] Test cmd failed, Exception: ()
Traceback (most recent call last):
File "test.py", line 21, in test_cmd
client.db_open(db_name, db_username, db_password)
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/orient.py", line 412, in db_open
.prepare((db_name, user, password, db_type, client_id)).send().fetch_response()
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/messages/database.py", line 101, in fetch_response
result = super(DbOpenMessage, self).fetch_response()
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/messages/base.py", line 265, in fetch_response
self._decode_all()
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/messages/base.py", line 250, in _decode_all
self._decode_body()
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/messages/base.py", line 242, in _decode_body
self._body.append( self._decode_field( field ) )
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/messages/base.py", line 366, in _decode_field
_decoded_string = self._orientSocket.read( _len )
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/orient.py", line 164, in read
buf = bytearray(_len_to_read)
MemoryError
[I 180322 15:56:20 test:19] come into test_cmd
[E 180322 15:56:20 test:30] Test cmd failed, Exception: ()
Traceback (most recent call last):
File "test.py", line 21, in test_cmd
client.db_open(db_name, db_username, db_password)
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/orient.py", line 412, in db_open
.prepare((db_name, user, password, db_type, client_id)).send().fetch_response()
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/messages/database.py", line 101, in fetch_response
result = super(DbOpenMessage, self).fetch_response()
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/messages/base.py", line 265, in fetch_response
self._decode_all()
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/messages/base.py", line 250, in _decode_all
self._decode_body()
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/messages/base.py", line 242, in _decode_body
self._body.append( self._decode_field( field ) )
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/messages/base.py", line 366, in _decode_field
_decoded_string = self._orientSocket.read( _len )
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/orient.py", line 164, in read
buf = bytearray(_len_to_read)
MemoryError
查看 OrientDB Server 的日志， 可以看到 OQueryParsingException。
虽然OrientDB Server 出现错误日志，但不影响 OrientDB Server 的正常使用，OrientDB Studio 也可以正常访问和使用。
xception `1320FF76` in storage `plocal:/opt/orientdb/databases/cmdb_test`: 2.2.31 (build 285537d2767275f460df32c6a3be01bfff6a517c,
branch 2.2.x)
com.orientechnologies.orient.core.exception.OQueryParsingException: Error on parsing query
Query: xxxxxxx
------^
DB name="cmdb_test"
at com.orientechnologies.orient.core.sql.filter.OSQLTarget.(OSQLTarget.java:74)
at com.orientechnologies.orient.core.sql.OSQLEngine.parseTarget(OSQLEngine.java:464)
at com.orientechnologies.orient.core.sql.OCommandExecutorSQLSelect.parse(OCommandExecutorSQLSelect.java:278)
at com.orientechnologies.orient.core.sql.OCommandExecutorSQLSelect.parse(OCommandExecutorSQLSelect.java:93)
at com.orientechnologies.orient.core.sql.OCommandExecutorSQLDelegate.parse(OCommandExecutorSQLDelegate.java:53)
at com.orientechnologies.orient.core.sql.OCommandExecutorSQLDelegate.parse(OCommandExecutorSQLDelegate.java:34)
at com.orientechnologies.orient.core.storage.impl.local.OAbstractPaginatedStorage.command(OAbstractPaginatedStorage.java:331
9)
at com.orientechnologies.orient.core.command.OCommandRequestTextAbstract.execute(OCommandRequestTextAbstract.java:69)
at com.orientechnologies.orient.server.network.protocol.binary.ONetworkProtocolBinary.command(ONetworkProtocolBinary.java:15
64)
at com.orientechnologies.orient.server.network.protocol.binary.ONetworkProtocolBinary.executeRequest(ONetworkProtocolBinary.
java:664)
at com.orientechnologies.orient.server.network.protocol.binary.ONetworkProtocolBinary.sessionRequest(ONetworkProtocolBinary.
java:398)
at com.orientechnologies.orient.server.network.protocol.binary.ONetworkProtocolBinary.execute(ONetworkProtocolBinary.java:21
7)
at com.orientechnologies.common.thread.OSoftThread.run(OSoftThread.java:82)
Caused by: com.orientechnologies.orient.core.exception.OCommandExecutionException: Class 'XXXXXXX' was not found in database 'cmdb_t
est'
DB name="cmdb_test"
at com.orientechnologies.orient.core.sql.filter.OSQLTarget.extractTargets(OSQLTarget.java:273)
at com.orientechnologies.orient.core.sql.filter.OSQLTarget.(OSQLTarget.java:64)
... 12 more
结合日志，分析发现： 一旦client.command() 执行出现异常，当前Client 就不能正常使用，即使去执行正常有效的sql_command 也不能执行获取结果集。
一个改进的策略是：
在发现client 不可用的时候（比如 catch 到 MemoryError），重置一下client。
test_cmd方法的修改如下：
def test_cmd(sql_cmd):
logging.info('come into test_cmd')
try:
client.db_open(db_name, db_username, db_password)
ret = client.command(sql_cmd)
logging.info('ret len: %s', len(ret))
except MemoryError as e:
global client
client = pyorient.OrientDB(cmdb_url, cmdb_port)
logging.exception("Test cmd failed, Exception: %s", e.args)
except Exception as e:
logging.exception("Test cmd failed, Exception: %s", e.args)
再次执行 test.py, 发现 在执行 sql_cmd_1 时出现了 MemoryError。但在后续执行sql_cmd_2 的时候可以正常执行。
(py2.7.13cmdb2.0) [root@test-app-1 misc]# python test.py
test.py:25: SyntaxWarning: name 'client' is used prior to global declaration
global client
[I 180322 16:13:21 test:19] come into test_cmd
[E 180322 16:13:21 test:27] Test cmd failed, Exception: ()
Traceback (most recent call last):
File "test.py", line 22, in test_cmd
ret = client.command(sql_cmd)
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/orient.py", line 462, in command
.prepare(( QUERY_CMD, ) + args).send().fetch_response()
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/messages/commands.py", line 144, in fetch_response
super( CommandMessage, self ).fetch_response()
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/messages/base.py", line 265, in fetch_response
self._decode_all()
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/messages/base.py", line 249, in _decode_all
self._decode_header()
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/messages/base.py", line 176, in _decode_header
serialized_exception = self._decode_field( FIELD_STRING )
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/messages/base.py", line 366, in _decode_field
_decoded_string = self._orientSocket.read( _len )
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/orient.py", line 164, in read
buf = bytearray(_len_to_read)
MemoryError
[I 180322 16:13:21 test:19] come into test_cmd
[E 180322 16:13:21 test:27] Test cmd failed, Exception: ()
Traceback (most recent call last):
File "test.py", line 22, in test_cmd
ret = client.command(sql_cmd)
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/orient.py", line 462, in command
.prepare(( QUERY_CMD, ) + args).send().fetch_response()
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/messages/commands.py", line 144, in fetch_response
super( CommandMessage, self ).fetch_response()
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/messages/base.py", line 265, in fetch_response
self._decode_all()
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/messages/base.py", line 249, in _decode_all
self._decode_header()
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/messages/base.py", line 176, in _decode_header
serialized_exception = self._decode_field( FIELD_STRING )
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/messages/base.py", line 366, in _decode_field
_decoded_string = self._orientSocket.read( _len )
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/orient.py", line 164, in read
buf = bytearray(_len_to_read)
MemoryError
[I 180322 16:13:21 test:19] come into test_cmd
[E 180322 16:13:21 test:27] Test cmd failed, Exception: ()
Traceback (most recent call last):
File "test.py", line 22, in test_cmd
ret = client.command(sql_cmd)
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/orient.py", line 462, in command
.prepare(( QUERY_CMD, ) + args).send().fetch_response()
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/messages/commands.py", line 144, in fetch_response
super( CommandMessage, self ).fetch_response()
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/messages/base.py", line 265, in fetch_response
self._decode_all()
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/messages/base.py", line 249, in _decode_all
self._decode_header()
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/messages/base.py", line 176, in _decode_header
serialized_exception = self._decode_field( FIELD_STRING )
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/messages/base.py", line 366, in _decode_field
_decoded_string = self._orientSocket.read( _len )
File "/root/.virtualenvs/py2.7.13cmdb2.0/lib/python2.7/site-packages/pyorient/orient.py", line 164, in read
buf = bytearray(_len_to_read)
MemoryError
[I 180322 16:13:21 test:19] come into test_cmd
[I 180322 16:13:23 test:23] ret len: 6109
扩展
同样的问题，在交互式命令行，会提示 timeout， 这个比较奇怪 :(
执行到 pyorient/orient.py read() 时候， 文件执行和命令行执行出现差别...
In [36]: sql_cmd_1 = 'select * from xxxxxxx'
In [37]: test_cmd(sql_cmd_1)
ERROR:root:Test cmd failed, Exception: ('timed out',)
Traceback (most recent call last):
File "", line 5, in test_cmd
ret = client.command(sql_cmd)
File "/root/.virtualenvs/py2.7.14cmdb2.0/lib/python2.7/site-packages/pyorient/orient.py", line 462, in command
.prepare(( QUERY_CMD, ) + args).send().fetch_response()
File "/root/.virtualenvs/py2.7.14cmdb2.0/lib/python2.7/site-packages/pyorient/messages/commands.py", line 144, in fetch_response
super( CommandMessage, self ).fetch_response()
File "/root/.virtualenvs/py2.7.14cmdb2.0/lib/python2.7/site-packages/pyorient/messages/base.py", line 265, in fetch_response
self._decode_all()
File "/root/.virtualenvs/py2.7.14cmdb2.0/lib/python2.7/site-packages/pyorient/messages/base.py", line 249, in _decode_all
self._decode_header()
File "/root/.virtualenvs/py2.7.14cmdb2.0/lib/python2.7/site-packages/pyorient/messages/base.py", line 176, in _decode_header
serialized_exception = self._decode_field( FIELD_STRING )
File "/root/.virtualenvs/py2.7.14cmdb2.0/lib/python2.7/site-packages/pyorient/messages/base.py", line 366, in _decode_field
_decoded_string = self._orientSocket.read( _len )
File "/root/.virtualenvs/py2.7.14cmdb2.0/lib/python2.7/site-packages/pyorient/orient.py", line 167, in read
n_bytes = self._socket.recv_into(view, _len_to_read)
timeout: timed out
附录：
class Exception(BaseException)
| Common base class for all non-exit exceptions.
|
| Method resolution order:
| Exception
| BaseException
| __builtin__.object
class MemoryError(StandardError)
| Out of memory.
|
| Method resolution order:
| MemoryError
| StandardError
| Exception
| BaseException
| __builtin__.object
|
class OrientDB(__builtin__.object)
| OrientDB client object
|
| Point of entrance to use the basic commands you can issue to the server
|
| :param host: hostname of the server to connect defaults to localhost
| :param port: integer port of the server defaults to 2424
|
| Usage::
|
| >>> from pyorient import OrientDB
| >>> client = OrientDB("localhost", 2424)
| >>> client.db_open('MyDatabase', 'admin', 'admin')
|
| Methods defined here:
|
| __getattr__(self, item)
|
| __init__(self, host='localhost', port=2424, serialization_type='ORecordDocument2csv')
|
| batch(self, *args)
|
| close(self)
|
| command(self, *args)
|
| db_open(self, db_name, user, password, db_type='document', client_id='')
| Opens a database on the remote OrientDB Server.
| Returns the Session-Id to being reused for all the next calls and the list of configured clusters
|
| :param db_name: database name as string. Example: "demo"
| :param user: username as string
| :param password: password as string
| :param db_type: string, can be DB_TYPE_DOCUMENT or DB_TYPE_GRAPH
| :param client_id: Can be null for clients. In clustered configuration is the distributed node
| :return: an array of :class:`OrientCluster ` object
|
| Usage::
|
| >>> import pyorient
| >>> orient = pyorient.OrientDB('localhost', 2424)
| >>> orient.db_open('asd', 'admin', 'admin')