| import sqlalchemy |
| from slavealloc import exceptions |
| from slavealloc.data import queries, model |
| |
| |
| class Allocation(object): |
| """ |
| |
| A container class to hold all of the information necessary to make an allocation |
| |
| @ivar slavename: the slave name |
| @ivar slaveid: its slaveid |
| @ivar enabled: true if this slave is enabled |
| @ivar master_nickname: master's nickname |
| @iver master_fqdn: master's hostname |
| @ivar master_pb_port: master's slave pb_port |
| @ivar slave_basedir: the slave's basedir |
| @ivar slave_password: the slave's password |
| @ivar masterid: the assigned masterid |
| """ |
| |
| slavename = slaveid = enabled = master_nickname = master_fqdn = None |
| master_pb_port = slave_basedir = slave_password = masterid = None |
| |
| def __init__(self, slavename): |
| self.slavename = slavename |
| |
| # slave info, including template |
| q = sqlalchemy.select( |
| [model.slaves, model.tac_templates.c.template], |
| whereclause=(model.slaves.c.name == slavename), |
| from_obj = [ |
| model.slaves.outerjoin( |
| model.tac_templates, |
| onclause=( |
| model.slaves.c.custom_tplid == model.tac_templates.c.tplid))]) |
| |
| slave_row = q.execute().fetchone() |
| if not slave_row: |
| raise exceptions.NoAllocationError |
| self.slaveid = slave_row.slaveid |
| self.enabled = slave_row.enabled |
| self.slave_basedir = slave_row.basedir |
| |
| # bail out early if this slave is not enabled |
| if not self.enabled: |
| return |
| |
| # slave password |
| q = queries.slave_password |
| self.slave_password = q.execute(slaveid=self.slaveid).scalar() |
| |
| # if this slave has a locked_masterid, just get that row; otherwise, run |
| # the self algorithm |
| if slave_row.locked_masterid: |
| q = model.masters.select(whereclause=( |
| model.masters.c.masterid == slave_row.locked_masterid)) |
| master_row = q.execute().fetchone() |
| else: |
| q = queries.best_master |
| master_row = q.execute(slaveid=self.slaveid).fetchone() |
| |
| if not master_row: |
| raise exceptions.NoAllocationError |
| self.master_nickname = master_row.nickname |
| self.master_fqdn = master_row.fqdn |
| self.master_pb_port = master_row.pb_port |
| self.masterid = master_row.masterid |
| |
| # get the desired template (or None for default) |
| self.template = slave_row.template |
| |
| def commit(self): |
| """ |
| Commit this allocation to the database |
| """ |
| # note that this will work correctly for enabled slaves |
| q = model.slaves.update( |
| whereclause=(model.slaves.c.slaveid == self.slaveid), |
| values=dict(current_masterid=self.masterid)) |
| q.execute() |
