db.py 16 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108
##############################################################################
# 
# Zope Public License (ZPL) Version 1.0
# -------------------------------------
# 
# Copyright (c) Digital Creations.  All rights reserved.
# 
# This license has been certified as Open Source(tm).
# 
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are
# met:
# 
# 1. Redistributions in source code must retain the above copyright
#    notice, this list of conditions, and the following disclaimer.
# 
# 2. Redistributions in binary form must reproduce the above copyright
#    notice, this list of conditions, and the following disclaimer in
#    the documentation and/or other materials provided with the
#    distribution.
# 
# 3. Digital Creations requests that attribution be given to Zope
#    in any manner possible. Zope includes a "Powered by Zope"
#    button that is installed by default. While it is not a license
#    violation to remove this button, it is requested that the
#    attribution remain. A significant investment has been put
#    into Zope, and this effort will continue if the Zope community
#    continues to grow. This is one way to assure that growth.
# 
# 4. All advertising materials and documentation mentioning
#    features derived from or use of this software must display
#    the following acknowledgement:
# 
#      "This product includes software developed by Digital Creations
#      for use in the Z Object Publishing Environment
#      (http://www.zope.org/)."
# 
#    In the event that the product being advertised includes an
#    intact Zope distribution (with copyright and license included)
#    then this clause is waived.
# 
# 5. Names associated with Zope or Digital Creations must not be used to
#    endorse or promote products derived from this software without
#    prior written permission from Digital Creations.
# 
# 6. Modified redistributions of any form whatsoever must retain
#    the following acknowledgment:
# 
#      "This product includes software developed by Digital Creations
#      for use in the Z Object Publishing Environment
#      (http://www.zope.org/)."
# 
#    Intact (re-)distributions of any official Zope release do not
#    require an external acknowledgement.
# 
# 7. Modifications are encouraged but must be packaged separately as
#    patches to official Zope releases.  Distributions that do not
#    clearly separate the patches from the original work must be clearly
#    labeled as unofficial distributions.  Modifications which do not
#    carry the name Zope may be packaged in any form, as long as they
#    conform to all of the clauses above.
# 
# 
# Disclaimer
# 
#   THIS SOFTWARE IS PROVIDED BY DIGITAL CREATIONS ``AS IS'' AND ANY
#   EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
#   IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
#   PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL DIGITAL CREATIONS OR ITS
#   CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
#   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
#   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
#   USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
#   ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
#   OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
#   OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
#   SUCH DAMAGE.
# 
# 
# This software consists of contributions made by Digital Creations and
# many individuals on behalf of Digital Creations.  Specific
# attributions are listed in the accompanying credits file.
# 
##############################################################################

'''$Id: db.py,v 1.20 2002/03/14 20:24:54 adustman Exp $'''
__version__='$Revision: 1.20 $'[11:-2]

import _mysql
import MySQLdb
from _mysql_exceptions import OperationalError, NotSupportedError
MySQLdb_version_required = (0,9,2)

_v = getattr(_mysql, 'version_info', (0,0,0))
if _v < MySQLdb_version_required:
    raise NotSupportedError, \
	"ZMySQLDA requires at least MySQLdb %s, %s found" % \
	(MySQLdb_version_required, _v)

from MySQLdb.converters import conversions
from MySQLdb.constants import FIELD_TYPE, CR, CLIENT
from Shared.DC.ZRDB.TM import TM
from DateTime import DateTime
from zLOG import LOG, ERROR, INFO

import string, sys
from string import strip, split, find, upper, rfind
from time import time
109
from thread import get_ident, allocate_lock
110

111 112
# Connection is unusable, reconnect if possible (if so, don't re-raise the
# exception), otherwise re-raise the exception.
113 114 115 116 117
hosed_connection = (
    CR.SERVER_GONE_ERROR,
    CR.SERVER_LOST
    )

118 119 120 121 122 123
# Connection is unusable and some earlier query caused the trouble.
# Reconnect *and* re-raise the exception.
dead_connection = (
    CR.COMMANDS_OUT_OF_SYNC,
    )

124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166
key_types = {
    "PRI": "PRIMARY KEY",
    "MUL": "INDEX",
    "UNI": "UNIQUE",
    }

field_icons = "bin", "date", "datetime", "float", "int", "text", "time"

icon_xlate = {
    "varchar": "text", "char": "text",
    "enum": "what", "set": "what",
    "double": "float", "numeric": "float",
    "blob": "bin", "mediumblob": "bin", "longblob": "bin",
    "tinytext": "text", "mediumtext": "text",
    "longtext": "text", "timestamp": "datetime",
    "decimal": "float", "smallint": "int",
    "mediumint": "int", "bigint": "int",
    }

type_xlate = {
    "double": "float", "numeric": "float",
    "decimal": "float", "smallint": "int",
    "mediumint": "int", "bigint": "int",
    "int": "int", "float": "float",
    "timestamp": "datetime", "datetime": "datetime",
    "time": "datetime",
    }
    
def _mysql_timestamp_converter(s):
	if len(s) < 14:
		s = s + "0"*(14-len(s))
        parts = map(int, (s[:4],s[4:6],s[6:8],
                          s[8:10],s[10:12],s[12:14]))
	return DateTime("%04d-%02d-%02d %02d:%02d:%02d" % tuple(parts))

def DateTime_or_None(s):
    try: return DateTime(s)
    except: return None

def int_or_long(s):
    try: return int(s)
    except: return long(s)

167 168 169 170 171 172
class ThreadedDB:
    """
      This class is an interface to DB.
      Its caracteristic is that an instance of this class interfaces multiple
      instanes of DB class, each one being bound to a specific thread.
    """
173 174 175 176 177 178 179 180 181

    conv=conversions.copy()
    conv[FIELD_TYPE.LONG] = int_or_long
    conv[FIELD_TYPE.DATETIME] = DateTime_or_None
    conv[FIELD_TYPE.DATE] = DateTime_or_None
    conv[FIELD_TYPE.DECIMAL] = float
    del conv[FIELD_TYPE.TIME]

    def __init__(self,connection):
182 183 184 185 186 187 188 189 190 191 192 193
        """
          Parse the connection string.
          Initiate a trial connection with the database to check
          transactionality once instead of once per DB instance.
        """
        self._connection = connection
        self._kw_args = self._parse_connection_string(connection)
        self._db_pool = {}
        self._db_lock = allocate_lock()
        connection = MySQLdb.connect(**self._kw_args)
        transactional = connection.server_capabilities & CLIENT.TRANSACTIONS
        connection.close()
194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237
        if self._try_transactions == '-':
            transactional = 0
        elif not transactional and self._try_transactions == '+':
            raise NotSupportedError, "transactions not supported by this server"
        self._use_TM = self._transactions = transactional
        if self._mysql_lock:
            self._use_TM = 1

    def _parse_connection_string(self, connection):
        kwargs = {'conv': self.conv}
        items = split(connection)
        self._use_TM = None
        if not items: return kwargs
        lockreq, items = items[0], items[1:]
        if lockreq[0] == "*":
            self._mysql_lock = lockreq[1:]
            db_host, items = items[0], items[1:]
            self._use_TM = 1
        else:
            self._mysql_lock = None
            db_host = lockreq
        if '@' in db_host:
            db, host = split(db_host,'@',1)
            kwargs['db'] = db
            if ':' in host:
                host, port = split(host,':',1)
                kwargs['port'] = int(port)
            kwargs['host'] = host
        else:
            kwargs['db'] = db_host
        if kwargs['db'] and kwargs['db'][0] in ('+', '-'):
            self._try_transactions = kwargs['db'][0]
            kwargs['db'] = kwargs['db'][1:]
        else:
            self._try_transactions = None
        if not kwargs['db']:
            del kwargs['db']
        if not items: return kwargs
        kwargs['user'], items = items[0], items[1:]
        if not items: return kwargs
        kwargs['passwd'], items = items[0], items[1:]
        if not items: return kwargs
        kwargs['unix_socket'], items = items[0], items[1:]
        return kwargs
238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306

    def _pool_set(self, key, value):
      self._db_lock.acquire()
      try:
        self._db_pool[key] = value
      finally:
        self._db_lock.release()

    def _pool_get(self, key):
      self._db_lock.acquire()
      try:
        return self._db_pool.get(key)
      finally:
        self._db_lock.release()

    def _access_db(self, method_id, args, kw):
        """
          Generic method to call pooled objects' methods.
          When the current thread had never issued any call, create a DB
          instance.
        """
        ident = get_ident()
        db = self._pool_get(ident)
        if db is None:
            db = DB(kw_args=self._kw_args, use_TM=self._use_TM,
                    mysql_lock=self._mysql_lock,
                    transactions=self._transactions)
            self._pool_set(ident, db)
        return getattr(db, method_id)(*args, **kw)

    def tables(self, *args, **kw):
        return self._access_db(method_id='tables', args=args, kw=kw)

    def columns(self, *args, **kw):
        return self._access_db(method_id='columns', args=args, kw=kw)

    def query(self, *args, **kw):
        return self._access_db(method_id='query', args=args, kw=kw)

    def string_literal(self, *args, **kw):
        return self._access_db(method_id='string_literal', args=args, kw=kw)

class DB(TM):

    defs={
        FIELD_TYPE.CHAR: "i", FIELD_TYPE.DATE: "d",
        FIELD_TYPE.DATETIME: "d", FIELD_TYPE.DECIMAL: "n",
        FIELD_TYPE.DOUBLE: "n", FIELD_TYPE.FLOAT: "n", FIELD_TYPE.INT24: "i",
        FIELD_TYPE.LONG: "i", FIELD_TYPE.LONGLONG: "l",
        FIELD_TYPE.SHORT: "i", FIELD_TYPE.TIMESTAMP: "d",
        FIELD_TYPE.TINY: "i", FIELD_TYPE.YEAR: "i",
        }

    _p_oid=_p_changed=_registered=None

    def __init__(self, kw_args, use_TM, mysql_lock, transactions):
        self._kw_args = kw_args
        self._mysql_lock = mysql_lock
        self._use_TM = use_TM
        self._transactions = transactions
        self._forceReconnection()

    def __del__(self):
      self.db.close()

    def _forceReconnection(self):
      db = MySQLdb.connect(**self._kw_args)
      self.db = db

307 308 309 310
    def tables(self, rdb=0,
               _care=('TABLE', 'VIEW')):
        r=[]
        a=r.append
311
        result = self._query("SHOW TABLES")
312
        row = result.fetch_row(1)
313
        while row:
314 315 316 317 318 319 320
            a({'TABLE_NAME': row[0][0], 'TABLE_TYPE': 'TABLE'})
            row = result.fetch_row(1)
        return r

    def columns(self, table_name):
        from string import join
        try:
321
            c = self._query('SHOW COLUMNS FROM %s' % table_name)
322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360
        except:
            return ()
        r=[]
        for Field, Type, Null, Key, Default, Extra in c.fetch_row(0):
            info = {}
            field_default = Default and "DEFAULT %s"%Default or ''
            if Default: info['Default'] = Default
            if '(' in Type:
                end = rfind(Type,')')
                short_type, size = split(Type[:end],'(',1)
                if short_type not in ('set','enum'):
                    if ',' in size:
                        info['Scale'], info['Precision'] = \
                                       map(int, split(size,',',1))
                    else:
                        info['Scale'] = int(size)
            else:
                short_type = Type
            if short_type in field_icons:
                info['Icon'] = short_type
            else:
                info['Icon'] = icon_xlate.get(short_type, "what")
            info['Name'] = Field
            info['Type'] = type_xlate.get(short_type,'string')
            info['Extra'] = Extra,
            info['Description'] = join([Type, field_default, Extra or '',
                                        key_types.get(Key, Key or ''),
                                        Null != 'YES' and 'NOT NULL' or '']),
            info['Nullable'] = (Null == 'YES') and 1 or 0
            if Key:
                info['Index'] = 1
            if Key == 'PRI':
                info['PrimaryKey'] = 1
                info['Unique'] = 1
            elif Key == 'UNI':
                info['Unique'] = 1
            r.append(info)
        return r

361
    def _query(self, query, force_reconnect=False):
362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384
        """
          Send a to MySQL server.
          It reconnects automaticaly if needed and the following conditions are
          met:
           - It has not just tried to reconnect (ie, this function will not
             attemp to connect twice per call).
           - This conection is not transactionnal and has set not MySQL locks,
             because they are bound to the connection. This check can be
             overridden by passing force_reconnect with True value.
        """
        try:
            self.db.query(query)
        except OperationalError, m:
            if ((not force_reconnect) and \
                (self._mysql_lock or self._transactions)) or \
               m[0] not in (hosed_connection + dead_connection):
                raise
            # Hm. maybe the db is hosed.  Let's restart it.
            self._forceReconnection()
            if m[0] in dead_connection:
                raise
            self.db.query(query)
        return self.db.store_result()
385

386 387 388 389
    def query(self,query_string, max_rows=1000):
        self._use_TM and self._register()
        desc=None
        result=()
390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405
        for qs in filter(None, map(strip,split(query_string, '\0'))):
            qtype = upper(split(qs, None, 1)[0])
            if qtype == "SELECT" and max_rows:
                qs = "%s LIMIT %d" % (qs,max_rows)
                r=0
            c = self._query(qs)
            if desc is not None:
                if c and (c.describe() != desc):
                    raise 'Query Error', (
                        'Multiple select schema are not allowed'
                        )
            if c:
                desc=c.describe()
                result=c.fetch_row(max_rows)
            else:
                desc=None
406 407 408 409 410 411 412 413 414 415 416 417 418 419 420

        if desc is None: return (),()

        items=[]
        func=items.append
        defs=self.defs
        for d in desc:
            item={'name': d[0],
                  'type': defs.get(d[1],"t"),
                  'width': d[2],
                  'null': d[6]
                 }
            func(item)
        return items, result

421
    def string_literal(self, s):
422
        return self.db.string_literal(s)
423 424 425

    def _begin(self, *ignored):
        try:
426
            self._transaction_begun = True
427 428
            # Ping the database to reconnect if connection was closed.
            self._query("SELECT 1", force_reconnect=True)
429
            if self._transactions:
430
                self._query("BEGIN")
431
            if self._mysql_lock:
432
                self._query("SELECT GET_LOCK('%s',0)" % self._mysql_lock)
433 434 435 436
        except:
            LOG('ZMySQLDA', ERROR, "exception during _begin",
                error=sys.exc_info())
            raise
437

438
    def _finish(self, *ignored):
439
        if not self._transaction_begun:
440
            return
441
        self._transaction_begun = False
442
        if self._mysql_lock:
443
            self._query("SELECT RELEASE_LOCK('%s')" % self._mysql_lock)
444
        if self._transactions:
445
            self._query("COMMIT")
446 447

    def _abort(self, *ignored):
448
        if not self._transaction_begun:
449
            return
450
        self._transaction_begun = False
451
        if self._mysql_lock:
452
            self._query("SELECT RELEASE_LOCK('%s')" % self._mysql_lock)
453
        if self._transactions:
454
            self._query("ROLLBACK")
455 456
        else:
            LOG('ZMySQLDA', ERROR, "aborting when non-transactional")
457