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# This file is part of Buildbot. Buildbot 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, version 2.
#
# This program 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
# this program; if not, write to the Free Software Foundation, Inc., 51
# Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
#
# Copyright Buildbot Team Members
from buildbot.util import json
import sqlalchemy as sa
import sqlalchemy.exc
from buildbot.db import base
class _IdNotFoundError(Exception):
pass # used internally
class ObjDict(dict):
pass
class StateConnectorComponent(base.DBConnectorComponent):
# Documentation is in developer/database.rst
def getObjectId(self, name, class_name):
# defer to a cached method that only takes one parameter (a tuple)
return self._getObjectId((name, class_name)
).addCallback(lambda objdict : objdict['id'])
@base.cached('objectids')
def _getObjectId(self, name_class_name_tuple):
name, class_name = name_class_name_tuple
def thd(conn):
objects_tbl = self.db.model.objects
self.check_length(objects_tbl.c.name, name)
self.check_length(objects_tbl.c.class_name, class_name)
def select():
q = sa.select([ objects_tbl.c.id ],
whereclause=((objects_tbl.c.name == name)
& (objects_tbl.c.class_name == class_name)))
res = conn.execute(q)
row = res.fetchone()
res.close()
if not row:
raise _IdNotFoundError
return row.id
def insert():
res = conn.execute(objects_tbl.insert(),
name=name,
class_name=class_name)
return res.inserted_primary_key[0]
# we want to try selecting, then inserting, but if the insert fails
# then try selecting again. We include an invocation of a hook
# method to allow tests to exercise this particular behavior
try:
return ObjDict(id=select())
except _IdNotFoundError:
pass
self._test_timing_hook(conn)
try:
return ObjDict(id=insert())
except (sqlalchemy.exc.IntegrityError,
sqlalchemy.exc.ProgrammingError):
pass
return ObjDict(id=select())
return self.db.pool.do(thd)
class Thunk: pass
def getState(self, objectid, name, default=Thunk):
def thd(conn):
object_state_tbl = self.db.model.object_state
q = sa.select([ object_state_tbl.c.value_json ],
whereclause=((object_state_tbl.c.objectid == objectid)
& (object_state_tbl.c.name == name)))
res = conn.execute(q)
row = res.fetchone()
res.close()
if not row:
if default is self.Thunk:
raise KeyError("no such state value '%s' for object %d" %
(name, objectid))
return default
try:
return json.loads(row.value_json)
except:
raise TypeError("JSON error loading state value '%s' for %d" %
(name, objectid))
return self.db.pool.do(thd)
def setState(self, objectid, name, value):
def thd(conn):
object_state_tbl = self.db.model.object_state
try:
value_json = json.dumps(value)
except:
raise TypeError("Error encoding JSON for %r" % (value,))
self.check_length(object_state_tbl.c.name, name)
def update():
q = object_state_tbl.update(
whereclause=((object_state_tbl.c.objectid == objectid)
& (object_state_tbl.c.name == name)))
res = conn.execute(q, value_json=value_json)
# check whether that worked
return res.rowcount > 0
def insert():
conn.execute(object_state_tbl.insert(),
objectid=objectid,
name=name,
value_json=value_json)
# try updating; if that fails, try inserting; if that fails, then
# we raced with another instance to insert, so let that instance
# win.
if update():
return
self._test_timing_hook(conn)
try:
insert()
except (sqlalchemy.exc.IntegrityError, sqlalchemy.exc.ProgrammingError):
pass # someone beat us to it - oh well
return self.db.pool.do(thd)
def _test_timing_hook(self, conn):
# called so tests can simulate another process inserting a database row
# at an inopportune moment
pass
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