Public feed
#892782
#!/usr/bin/env pythonfrom elixir import *from sqlalchemy import *import threadingclass Project(Entity): has_field('name', Unicode, primary_key=True)class ProjectIdMapperExtension(MapperExtension): def before_insert(self, mapper, connection, instance): # If we don't have an ID already, # grab the next ID in this project if not instance.id: # Grab the underlying SQLAlchemy table ticket_table = instance._descriptor.entity.table if not hasattr(self, '_thread_local'): self._thread_local = threading.local() if not hasattr(self._thread_local, 'projects'): self._thread_local.projects = {} project_contexts = self._thread_local.projects # Check if we already have an entry for this project if project_contexts.has_key(instance.project_name): project_contexts[instance.project_name] += 1 else: # No entry -- query for the next ID qry = select([func.max(instance.c.id)], instance.c.project_name == instance.project_name) rproxy = qry.execute() last_id = rproxy.fetchone()[0] if not last_id: last_id = 0 project_contexts[instance.project_name] = last_id + 1 instance.id = project_contexts[instance.project_name] def after_insert(self, mapper, connection, instance): # After this insert is over, trash the counter (it may well expire) if hasattr(self, '_thread_local'): if hasattr(self._thread_local, 'projects'): del self._thread_local.projectsfrom elixir.fields import Statement, HasFieldfrom elixir.relationships import BelongsTofrom elixir.options import UsingMapperOptionsclass ProjectId(object): def __init__(self, entity): BelongsTo(entity, 'project', of_kind='Project', column_kwargs={"primary_key": True}) HasField(entity, 'id', Integer, default=0, primary_key=True, autoincrement=False) UsingMapperOptions(entity, extension=ProjectIdMapperExtension())has_project_and_id = Statement(ProjectId)class Milestone(Entity): has_project_and_id() has_field('name', Unicode)metadata.connect("sqlite://in_memory")metadata.engine.echo = Truecreate_all()y = Project(name='fizzle')x = Milestone(project=y, name='stuff0')n = Milestone(project=y, name='stuff1')n = Milestone(project=y, name='stuff2')objectstore.flush()