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R3600/invenio/legacy/dbquery_postgresql.py
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# This file is part of Invenio.
# Copyright (C) 2008, 2009, 2010, 2011, 2012, 2013, 2014 CERN.
#
# Invenio is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License as
# published by the Free Software Foundation; either version 2 of the
# License, or (at your option) any later version.
#
# Invenio is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
# General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Invenio; if not, write to the Free Software Foundation, Inc.,
# 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
"""
Invenio utilities to run SQL queries.
The main API functions are:
- run_sql()
- run_sql_many()
- run_sql_with_limit()
but see the others as well.
"""
from __future__ import print_function
# dbquery clients can import these from here:
# pylint: disable=W0611
from sqlalchemy.exc import (
SQLAlchemyError as Error, InterfaceError, DataError,
DatabaseError, OperationalError, IntegrityError,
InternalError, NotSupportedError,
ProgrammingError)
import gc
import os
import string
import time
import re
import sys
import warnings
from flask import current_app, has_app_context
from invenio.base.globals import cfg
from invenio.ext.sqlalchemy import db
from invenio.utils.serializers import serialize_via_marshal, \
deserialize_via_marshal
def _db_login(*args, **kwargs):
warnings.warn("Use of _db_login is obsolete for postgresql.",
DeprecationWarning)
class InvenioDbQueryWildcardLimitError(Exception):
"""Exception raised when query limit reached."""
def __init__(self, res):
"""Initialization."""
self.res = res
def run_sql(sql, param=None, n=0, with_desc=False, with_dict=False, run_on_slave=False, connection=None):
"""Run SQL on the server with PARAM and return result.
:param param: tuple of string params to insert in the query (see
notes below)
:param n: number of tuples in result (0 for unbounded)
:param with_desc: if True, will return a DB API 7-tuple describing
columns in query.
:param with_dict: if True, will return a list of dictionaries
composed of column-value pairs
:param connection: if provided, uses the given connection.
:return: If SELECT, SHOW, DESCRIBE statements, return tuples of data,
followed by description if parameter with_desc is
provided.
If SELECT and with_dict=True, return a list of dictionaries
composed of column-value pairs, followed by description
if parameter with_desc is provided.
If INSERT, return last row id.
Otherwise return SQL result as provided by database.
@note: When the site is closed for maintenance (as governed by the
config variable CFG_ACCESS_CONTROL_LEVEL_SITE), do not attempt
to run any SQL queries but return empty list immediately.
Useful to be able to have the website up while MySQL database
is down for maintenance, hot copies, table repairs, etc.
@note: In case of problems, exceptions are returned according to
the Python DB API 2.0. The client code can import them from
this file and catch them.
"""
if cfg['CFG_ACCESS_CONTROL_LEVEL_SITE'] == 3:
# do not connect to the database as the site is closed for maintenance:
return []
elif cfg['CFG_ACCESS_CONTROL_LEVEL_SITE'] > 0:
## Read only website
if not sql.upper().startswith("SELECT") and not sql.upper().startswith("SHOW"):
return
if param:
param = tuple(param)
#FIXME port database slave support
dbhost = cfg['CFG_DATABASE_HOST']
if run_on_slave and cfg['CFG_DATABASE_SLAVE']:
dbhost = cfg['CFG_DATABASE_SLAVE']
if 'sql-logger' in cfg.get('CFG_DEVEL_TOOLS', []):
log_sql_query(dbhost, sql, param)
gc.disable()
engine = db.engine.execution_options(use_unicode=0)
sql = sql.replace('`', '"')
current_app.logger.info(sql)
if param is None:
cur = engine.execute(sql.replace('%', '%%'))
else:
cur = engine.execute(sql, (param, ))
gc.enable()
if string.upper(string.split(sql)[0]) in ("SELECT", "SHOW", "DESC", "DESCRIBE"):
if n:
recset = cur.fetchmany(n)
else:
recset = cur.fetchall()
from invenio.base.helpers import utf8ifier
recset = map(dict if with_dict else tuple, recset)
recset = utf8ifier(recset)
if with_desc:
return recset, cur.description
else:
return recset
else:
if string.upper(string.split(sql)[0]) == "INSERT":
return cur.lastrowid
return cur
def run_sql_many(query, params, limit=None, run_on_slave=False):
"""Run SQL on the server with PARAM.
This method does executemany and is therefore more efficient than execute
but it has sense only with queries that affect state of a database
(INSERT, UPDATE). That is why the results just count number of affected rows
:param params: tuple of tuple of string params to insert in the query
:param limit: query will be executed in parts when number of
parameters is greater than limit (each iteration runs at most
`limit' parameters)
:return: SQL result as provided by database
"""
if limit is None:
limit = cfg['CFG_MISCUTIL_SQL_RUN_SQL_MANY_LIMIT']
if cfg['CFG_ACCESS_CONTROL_LEVEL_SITE'] == 3:
# do not connect to the database as the site is closed for maintenance:
return []
elif cfg['CFG_ACCESS_CONTROL_LEVEL_SITE'] > 0:
## Read only website
if not query.upper().startswith("SELECT") and not query.upper().startswith("SHOW"):
return
dbhost = cfg['CFG_DATABASE_HOST']
if run_on_slave and cfg['CFG_DATABASE_SLAVE']:
dbhost = cfg['CFG_DATABASE_SLAVE']
i = 0
r = None
while i < len(params):
## make partial query safely (mimicking procedure from run_sql())
gc.disable()
rc = db.session.execute(query, params[i:i + limit]).fetchall()
gc.enable()
## collect its result:
if r is None:
r = rc
else:
r += rc
i += limit
return r
def blob_to_string(ablob):
"""Return string representation of ABLOB. Useful to treat MySQL
BLOBs in the same way for both recent and old MySQLdb versions.
"""
if ablob:
if type(ablob) is str:
# BLOB is already a string in MySQLdb 0.9.2
return ablob
else:
# BLOB is array.array in MySQLdb 1.0.0 and later
return ablob.tostring()
else:
return ablob
def log_sql_query(dbhost, sql, param=None):
"""
Log SQL query into prefix/var/log/dbquery.log log file. In order
to enable logging of all SQL queries, please uncomment one line
in run_sql() above. Useful for fine-level debugging only!
"""
from invenio.utils.date import convert_datestruct_to_datetext
from invenio.utils.text import indent_text
date_of_log = convert_datestruct_to_datetext(time.localtime())
message = date_of_log + '-->\n'
message += indent_text('Host:\n' + indent_text(str(dbhost), 2, wrap=True), 2)
message += indent_text('Query:\n' + indent_text(str(sql), 2, wrap=True), 2)
message += indent_text('Params:\n' + indent_text(str(param), 2, wrap=True), 2)
message += '-----------------------------\n\n'
if has_app_context():
current_app.logger.info(message)
else:
print(message, file=sys.stderr)
def get_table_update_time(tablename, run_on_slave=False):
"""Return update time of TABLENAME. TABLENAME can contain
wildcard `%' in which case we return the maximum update time
value.
"""
# Note: in order to work with all of MySQL 4.0, 4.1, 5.0, this
# function uses SHOW TABLE STATUS technique with a dirty column
# position lookup to return the correct value. (Making use of
# Index_Length column that is either of type long (when there are
# some indexes defined) or of type None (when there are no indexes
# defined, e.g. table is empty). When we shall use solely
# MySQL-5.0, we can employ a much cleaner technique of using
# SELECT UPDATE_TIME FROM INFORMATION_SCHEMA.TABLES WHERE
# table_name='collection'.
res = run_sql("SHOW TABLE STATUS LIKE %s", (tablename,),
run_on_slave=run_on_slave)
update_times = [] # store all update times
for row in res:
if type(row[10]) is long or \
row[10] is None:
# MySQL-4.1 and 5.0 have creation_time in 11th position,
# so return next column:
update_times.append(str(row[12]))
else:
# MySQL-4.0 has creation_time in 10th position, which is
# of type datetime.datetime or str (depending on the
# version of MySQLdb), so return next column:
update_times.append(str(row[11]))
return max(update_times)
def get_table_status_info(tablename, run_on_slave=False):
"""Return table status information on TABLENAME. Returned is a
dict with keys like Name, Rows, Data_length, Max_data_length,
etc. If TABLENAME does not exist, return empty dict.
"""
# Note: again a hack so that it works on all MySQL 4.0, 4.1, 5.0
res = run_sql("SHOW TABLE STATUS LIKE %s", (tablename,),
run_on_slave=run_on_slave)
table_status_info = {} # store all update times
for row in res:
if type(row[10]) is long or \
row[10] is None:
# MySQL-4.1 and 5.0 have creation time in 11th position:
table_status_info['Name'] = row[0]
table_status_info['Rows'] = row[4]
table_status_info['Data_length'] = row[6]
table_status_info['Max_data_length'] = row[8]
table_status_info['Create_time'] = row[11]
table_status_info['Update_time'] = row[12]
else:
# MySQL-4.0 has creation_time in 10th position, which is
# of type datetime.datetime or str (depending on the
# version of MySQLdb):
table_status_info['Name'] = row[0]
table_status_info['Rows'] = row[3]
table_status_info['Data_length'] = row[5]
table_status_info['Max_data_length'] = row[7]
table_status_info['Create_time'] = row[10]
table_status_info['Update_time'] = row[11]
return table_status_info
def wash_table_column_name(colname):
"""
Evaluate table-column name to see if it is clean.
This function accepts only names containing [a-zA-Z0-9_].
:param colname: The string to be checked
@type colname: str
:return: colname if test passed
:raise Exception: Raises an exception if colname is invalid.
"""
if re.search('[^\w]', colname):
raise Exception('The table column %s is not valid.' % repr(colname))
return colname
def real_escape_string(unescaped_string, run_on_slave=False):
"""
Escapes special characters in the unescaped string for use in a DB query.
:param unescaped_string: The string to be escaped
@type unescaped_string: str
:return: Returns the escaped string
"""
dbhost = cfg['CFG_DATABASE_HOST']
if run_on_slave and cfg['CFG_DATABASE_SLAVE']:
dbhost = cfg['CFG_DATABASE_SLAVE']
connection_object = db.engine.raw_connection()
escaped_string = connection_object.escape(unescaped_string)
return escaped_string
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