我正在使用post-save signal作为模型来启动芹菜任务。它以前曾经工作过，但是突然之间，它给了我一个 TransactionManagementError 。
模型
class FieldSightXF(models.Model):
xf = models.ForeignKey(XForm, related_name="field_sight_form")
site = models.ForeignKey(Site, related_name="site_forms", null=True, blank=True)
project = models.ForeignKey(Project, related_name="project_forms", null=True, blank=True)
is_staged = models.BooleanField(default=False)
is_scheduled = models.BooleanField(default=False)
date_created = models.DateTimeField(auto_now=True)
date_modified = models.DateTimeField(auto_now=True)
schedule = models.OneToOneField(Schedule, blank=True, null=True, related_name="schedule_forms")
stage = models.OneToOneField(Stage, blank=True, null=True, related_name="stage_forms")
shared_level = models.IntegerField(default=2, choices=SHARED_LEVEL)
form_status = models.IntegerField(default=0, choices=FORM_STATUS)
fsform = models.ForeignKey('self', blank=True, null=True, related_name="parent")
is_deployed = models.BooleanField(default=False)
is_deleted = models.BooleanField(default=False)
is_survey = models.BooleanField(default=False)
from_project = models.BooleanField(default=True)
default_submission_status = models.IntegerField(default=0, choices=FORM_STATUS)
logs = GenericRelation('eventlog.FieldSightLog')
class Meta:
db_table = 'fieldsight_forms_data'
# unique_together = (("xf", "site"), ("xf", "is_staged", "stage"),("xf", "is_scheduled", "schedule"))
verbose_name = _("XForm")
verbose_name_plural = _("XForms")
ordering = ("-date_created",)
保存后信号
@receiver(post_save, sender=FieldSightXF)
def share_form(sender, instance, created, **kwargs):
if instance.project is not None and created:
from onadata.apps.fsforms.tasks import share_form_managers
task_obj = CeleryTaskProgress.objects.create(user=instance.xf.user,
description="Share Forms",
task_type=17, content_object=instance)
if task_obj:
try:
share_form_managers.delay(instance.id, task_obj.id)
except:
pass
post_save.connect(create_messages, sender=FieldSightXF)
CeleryTaskProgress用于跟踪芹菜任务的进度。
任务
@shared_task(max_retires=5)
def share_form_managers(fxf, task_id):
fxf = FieldSightXF.objects.get(pk=fxf)
userrole = UserRole.objects.filter(project=fxf.project, group__name='Project Manager')
users = User.objects.filter(user_roles__in=userrole)
shared = share_form(users, fxf.xf)
if shared:
CeleryTaskProgress.objects.filter(id=task_id).update(status=2)
else:
CeleryTaskProgress.objects.filter(id=task_id).update(status=3)
share_form方法
def share_form(users, xform):
from onadata.apps.fsforms.models import ObjectPermission, Asset
for user in users:
try:
codenames = ['view_asset', 'change_asset']
permissions = Permission.objects.filter(content_type__app_label='kpi', codename__in=codenames)
for perm in permissions:
object_id = Asset.objects.get(uid=xform.id_string).id
content_type = ContentType.objects.get(id=21)
# Create the new permission
new_permission = ObjectPermission.objects.create(
object_id=object_id,
content_type=content_type,
user=user,
permission_id=perm.pk,
deny=False,
inherited=False
)
except:
return False
else:
return True
此过程的作用是，只要创建FieldSightXF的对象（将表单分配给项目），该表单就会共享给该项目的项目经理。
以前，我将FieldSightXF对象作为参数传递给任务没有问题，但是现在我将对象id传递为：
以前
share_form_managers.delay(instance, task_obj.id)
当前
share_form_managers.delay(instance.id, task_obj.id)
现在，这两种情况都给了我提到的错误。 如果我从保存后信号方法中注释以上行，则错误消失了。
我确实尝试了针对类似问题的其他答案中的建议，但是它们对我没有用。
完整错误回溯：
ERROR 2019-06-13 10:49:50,743 base 11527 140653367232256 Internal Server Error: /forms/api/fxf/
Traceback (most recent call last):
File "/home/sanip/.virtualenvs/kobocat/lib/python2.7/site-packages/django/core/handlers/base.py", line 132, in get_response
response = wrapped_callback(request, *callback_args, **callback_kwargs)
File "/home/sanip/.virtualenvs/kobocat/lib/python2.7/site-packages/django/views/decorators/csrf.py", line 58, in wrapped_view
return view_func(*args, **kwargs)
File "/home/sanip/.virtualenvs/kobocat/lib/python2.7/site-packages/rest_framework/viewsets.py", line 87, in view
return self.dispatch(request, *args, **kwargs)
File "/home/sanip/.virtualenvs/kobocat/lib/python2.7/site-packages/rest_framework/views.py", line 466, in dispatch
response = self.handle_exception(exc)
File "/home/sanip/.virtualenvs/kobocat/lib/python2.7/site-packages/rest_framework/views.py", line 463, in dispatch
response = handler(request, *args, **kwargs)
File "/home/sanip/.virtualenvs/kobocat/lib/python2.7/site-packages/rest_framework/mixins.py", line 21, in create
self.perform_create(serializer)
File "/home/sanip/naxa/source/fieldsight/onadata/apps/fsforms/viewsets/FieldSightXformViewset.py", line 85, in perform_create
fxf.save()
File "/home/sanip/.virtualenvs/kobocat/lib/python2.7/site-packages/django/db/models/base.py", line 734, in save
force_update=force_update, update_fields=update_fields)
File "/home/sanip/.virtualenvs/kobocat/lib/python2.7/site-packages/django/db/models/base.py", line 762, in save_base
updated = self._save_table(raw, cls, force_insert, force_update, using, update_fields)
File "/home/sanip/.virtualenvs/kobocat/lib/python2.7/site-packages/django/db/models/base.py", line 827, in _save_table
forced_update)
File "/home/sanip/.virtualenvs/kobocat/lib/python2.7/site-packages/django/db/models/base.py", line 877, in _do_update
return filtered._update(values) > 0
File "/home/sanip/.virtualenvs/kobocat/lib/python2.7/site-packages/django/db/models/query.py", line 580, in _update
return query.get_compiler(self.db).execute_sql(CURSOR)
File "/home/sanip/.virtualenvs/kobocat/lib/python2.7/site-packages/django/db/models/sql/compiler.py", line 1062, in execute_sql
cursor = super(SQLUpdateCompiler, self).execute_sql(result_type)
File "/home/sanip/.virtualenvs/kobocat/lib/python2.7/site-packages/django/db/models/sql/compiler.py", line 840, in execute_sql
cursor.execute(sql, params)
File "/home/sanip/.virtualenvs/kobocat/lib/python2.7/site-packages/django/db/backends/utils.py", line 79, in execute
return super(CursorDebugWrapper, self).execute(sql, params)
File "/home/sanip/.virtualenvs/kobocat/lib/python2.7/site-packages/django/db/backends/utils.py", line 59, in execute
self.db.validate_no_broken_transaction()
File "/home/sanip/.virtualenvs/kobocat/lib/python2.7/site-packages/django/db/backends/base/base.py", line 327, in validate_no_broken_transaction
"An error occurred in the current transaction. You can't "
TransactionManagementError: An error occurred in the current transaction. You can't execute queries until the end of the 'atomic' block.
Internal Server Error: /forms/api/fxf/
Traceback (most recent call last):
File "/home/sanip/.virtualenvs/kobocat/lib/python2.7/site-packages/django/core/handlers/base.py", line 132, in get_response
response = wrapped_callback(request, *callback_args, **callback_kwargs)
File "/home/sanip/.virtualenvs/kobocat/lib/python2.7/site-packages/django/views/decorators/csrf.py", line 58, in wrapped_view
return view_func(*args, **kwargs)
File "/home/sanip/.virtualenvs/kobocat/lib/python2.7/site-packages/rest_framework/viewsets.py", line 87, in view
return self.dispatch(request, *args, **kwargs)
File "/home/sanip/.virtualenvs/kobocat/lib/python2.7/site-packages/rest_framework/views.py", line 466, in dispatch
response = self.handle_exception(exc)
File "/home/sanip/.virtualenvs/kobocat/lib/python2.7/site-packages/rest_framework/views.py", line 463, in dispatch
response = handler(request, *args, **kwargs)
File "/home/sanip/.virtualenvs/kobocat/lib/python2.7/site-packages/rest_framework/mixins.py", line 21, in create
self.perform_create(serializer)
File "/home/sanip/naxa/source/fieldsight/onadata/apps/fsforms/viewsets/FieldSightXformViewset.py", line 85, in perform_create
fxf.save()
File "/home/sanip/.virtualenvs/kobocat/lib/python2.7/site-packages/django/db/models/base.py", line 734, in save
force_update=force_update, update_fields=update_fields)
File "/home/sanip/.virtualenvs/kobocat/lib/python2.7/site-packages/django/db/models/base.py", line 762, in save_base
updated = self._save_table(raw, cls, force_insert, force_update, using, update_fields)
File "/home/sanip/.virtualenvs/kobocat/lib/python2.7/site-packages/django/db/models/base.py", line 827, in _save_table
forced_update)
File "/home/sanip/.virtualenvs/kobocat/lib/python2.7/site-packages/django/db/models/base.py", line 877, in _do_update
return filtered._update(values) > 0
File "/home/sanip/.virtualenvs/kobocat/lib/python2.7/site-packages/django/db/models/query.py", line 580, in _update
return query.get_compiler(self.db).execute_sql(CURSOR)
File "/home/sanip/.virtualenvs/kobocat/lib/python2.7/site-packages/django/db/models/sql/compiler.py", line 1062, in execute_sql
cursor = super(SQLUpdateCompiler, self).execute_sql(result_type)
File "/home/sanip/.virtualenvs/kobocat/lib/python2.7/site-packages/django/db/models/sql/compiler.py", line 840, in execute_sql
cursor.execute(sql, params)
File "/home/sanip/.virtualenvs/kobocat/lib/python2.7/site-packages/django/db/backends/utils.py", line 79, in execute
return super(CursorDebugWrapper, self).execute(sql, params)
File "/home/sanip/.virtualenvs/kobocat/lib/python2.7/site-packages/django/db/backends/utils.py", line 59, in execute
self.db.validate_no_broken_transaction()
File "/home/sanip/.virtualenvs/kobocat/lib/python2.7/site-packages/django/db/backends/base/base.py", line 327, in validate_no_broken_transaction
"An error occurred in the current transaction. You can't "
TransactionManagementError: An error occurred in the current transaction. You can't execute queries until the end of the 'atomic' block.
从回溯开始，以下代码指出了错误：
def perform_create(self, serializer):
is_survey = self.request.data.get('is_survey', False)
fxf = serializer.save(is_survey=is_survey, is_deployed=True)
if not fxf.project:
fxf.from_project = False
fxf.save() #<<--here
if fxf.project:
if not fxf.is_survey:
org = fxf.project.organization
fxf.logs.create(source=self.request.user, type=18, title="General",
organization=org,
project = fxf.project,
content_object=fxf,
extra_object=fxf.project,
description='{0} assigned new General form {1} to {2} '.format(
self.request.user.get_full_name(),
fxf.xf.title,
fxf.project.name))
else:
org = fxf.site.project.organization
fxf.logs.create(source=self.request.user, type=19, title="General",
organization=org,
project=fxf.site.project,
site = fxf.site,
content_object=fxf,
extra_object=fxf.site,
description='{0} assigned new General form {1} to {2} '.format(
self.request.user.get_full_name(),
fxf.xf.title,
fxf.site.name
))
perform_create是视图集中的一种方法，在将表单分配给项目时使用。
答案 0 :(得分：1)
出现错误，看来您在数据库级别或视图级别都启用了原子事务。
在阅读完您的代码后，这个问题对我来说就像这样。
您从perform_create视图创建了一个新的FieldSightXF对象，但是由于启用了原子事务，因此该对象实际上尚未存储在数据库中，当整个代码将被执行并将响应返回给用户。
现在，当您调用 fxf.save（）时，将处理 post_save_signal信号，并调用函数share_form 。
@receiver(post_save, sender=FieldSightXF)
def share_form(sender, instance, created, **kwargs):
if instance.project is not None and created:
from onadata.apps.fsforms.tasks import share_form_managers
task_obj = CeleryTaskProgress.objects.create(user=instance.xf.user,
description="Share Forms",
task_type=17, content_object=instance)
if task_obj:
try:
share_form_managers.delay(instance.id, task_obj.id)
except:
pass
post_save.connect(create_messages, sender=FieldSightXF)
在share_form函数中，您使用FieldSightXF对象的ID调用了任务share_form_managers 。
现在，当 celery执行您的任务时，这样做命中数据库以查找ID = fxf的FieldSightXF对象和ID = task_id的CeleryTaskProgress对象，它找不到它，因为它在数据库中还不存在，并且引发数据库错误。
@shared_task(max_retires=5)
def share_form_managers(fxf, task_id):
fxf = FieldSightXF.objects.get(pk=fxf) #<<--here
userrole = UserRole.objects.filter(project=fxf.project, group__name='Project Manager')
users = User.objects.filter(user_roles__in=userrole)
shared = share_form(users, fxf.xf)
if shared:
CeleryTaskProgress.objects.filter(id=task_id).update(status=2)
else:
CeleryTaskProgress.objects.filter(id=task_id).update(status=3)
如果在事务块内发生数据库错误， django会阻止任何更多数据库查询以停止损坏的数据读/写。
在perform_create函数中，您正在尝试在fxf.save（）之后读取/写入数据，因此django会引发事务错误。
def perform_create(self, serializer):
is_survey = self.request.data.get('is_survey', False)
fxf = serializer.save(is_survey=is_survey, is_deployed=True)
if not fxf.project:
fxf.from_project = False
fxf.save() #<<--here
if fxf.project:
if not fxf.is_survey:
org = fxf.project.organization
fxf.logs.create(source=self.request.user, type=18, title="General",
organization=org,
project = fxf.project,
content_object=fxf,
extra_object=fxf.project,
description='{0} assigned new General form {1} to {2} '.format(
self.request.user.get_full_name(),
fxf.xf.title,
fxf.project.name))
else:
org = fxf.site.project.organization
fxf.logs.create(source=self.request.user, type=19, title="General",
organization=org,
project=fxf.site.project,
site = fxf.site,
content_object=fxf,
extra_object=fxf.site,
description='{0} assigned new General form {1} to {2} '.format(
self.request.user.get_full_name(),
fxf.xf.title,
fxf.site.name
))
我建议您不要使用post_save信号，而是从perform_create视图中调用share_form_managers任务，如下所示：
from django.db import transaction
def perform_create(self, serializer):
is_survey = self.request.data.get('is_survey', False)
fxf = serializer.save(is_survey=is_survey, is_deployed=True)
if not fxf.project:
fxf.from_project = False
fxf.save()
if fxf.project:
# calling the task
from onadata.apps.fsforms.tasks import share_form_managers
task_obj = CeleryTaskProgress.objects.create(user=fxf.xf.user, description="Share Forms", task_type=17, content_object=instance)
if task_obj:
try:
transaction.on_commit(lambda: share_form_managers.delay(instance.id, task_obj.id))
except:
pass
# call block end
if not fxf.is_survey:
org = fxf.project.organization
fxf.logs.create(source=self.request.user, type=18, title="General", organization=org, project = fxf.project, content_object=fxf,extra_object=fxf.project, description='{0} assigned new General form {1} to {2} '.format(self.request.user.get_full_name(),fxf.xf.title,fxf.project.name))
else:
org = fxf.site.project.organization
fxf.logs.create(source=self.request.user, type=19, title="General", organization=org, project=fxf.site.project, site = fxf.site, content_object=fxf, extra_object=fxf.site, description='{0} assigned new General form {1} to {2} '.format(self.request.user.get_full_name(),fxf.xf.title,fxf.site.name ))
让我知道是否有帮助。
这里是django交易管理的参考： https://docs.djangoproject.com/en/2.2/topics/db/transactions/