---
url: "https://vueda.dev/v3/reference/api/py/vueda.workflow.models/TransitionPermission.md"
title: "TransitionPermission"
---

# TransitionPermission

## Overview

One permission that a user must hold to execute a transition.

``check_transition_permission`` allows the transition only when it has at least one row and
the user holds every permission that the rows name. It checks those permissions against the
object so that state rules and row-level hooks apply. It denies a transition with no rows to
every user, superusers included. Only programmatic use (``user=None``) passes the check for
such a transition, which keeps it for system use.

## `DoesNotExist` {#DoesNotExist}

The requested object does not exist

### Source {#DoesNotExist-source}

`server/vueda/workflow/models.py`

## `MultipleObjectsReturned` {#MultipleObjectsReturned}

The query returned multiple objects when only one was expected.

### Source {#MultipleObjectsReturned-source}

`server/vueda/workflow/models.py`

## `NotUpdated` {#NotUpdated}

The updated object no longer exists.

### Source {#NotUpdated-source}

`server/vueda/workflow/models.py`

## `historical_permission_codename` {#historical_permission_codename}

A wrapper for a deferred-loading field. When the value is read from this
object the first time, the query is executed.

### Signature {#historical_permission_codename-signature}

`historical_permission_codename(unknown)`

#### Parameters {#historical_permission_codename-parameters}

| Name | Type | Required | Default | Description |
| --- | --- | --- | --- | --- |
| <span id="historical_permission_codename-param-unknown">unknown</span> |  | yes |  |  |

## `historical_permission_content_type_app_label` {#historical_permission_content_type_app_label}

A wrapper for a deferred-loading field. When the value is read from this
object the first time, the query is executed.

### Signature {#historical_permission_content_type_app_label-signature}

`historical_permission_content_type_app_label(unknown)`

#### Parameters {#historical_permission_content_type_app_label-parameters}

| Name | Type | Required | Default | Description |
| --- | --- | --- | --- | --- |
| <span id="historical_permission_content_type_app_label-param-unknown">unknown</span> |  | yes |  |  |

## `historical_permission_content_type_model_name` {#historical_permission_content_type_model_name}

A wrapper for a deferred-loading field. When the value is read from this
object the first time, the query is executed.

### Signature {#historical_permission_content_type_model_name-signature}

`historical_permission_content_type_model_name(unknown)`

#### Parameters {#historical_permission_content_type_model_name-parameters}

| Name | Type | Required | Default | Description |
| --- | --- | --- | --- | --- |
| <span id="historical_permission_content_type_model_name-param-unknown">unknown</span> |  | yes |  |  |

## `id` {#id}

A wrapper for a deferred-loading field. When the value is read from this
object the first time, the query is executed.

### Signature {#id-signature}

`id(unknown)`

#### Parameters {#id-parameters}

| Name | Type | Required | Default | Description |
| --- | --- | --- | --- | --- |
| <span id="id-param-unknown">unknown</span> |  | yes |  |  |

## `objects` {#objects}

### Signature {#objects-signature}

`objects(unknown)`

#### Parameters {#objects-parameters}

| Name | Type | Required | Default | Description |
| --- | --- | --- | --- | --- |
| <span id="objects-param-unknown">unknown</span> |  | yes |  |  |

## `pgh_event_model` {#pgh_event_model}

A descriptor for accessing the pgh_event_model field on a tracked model

### Signature {#pgh_event_model-signature}

`pgh_event_model(unknown)`

#### Parameters {#pgh_event_model-parameters}

| Name | Type | Required | Default | Description |
| --- | --- | --- | --- | --- |
| <span id="pgh_event_model-param-unknown">unknown</span> |  | yes |  |  |

## `save` {#save}

Save the current instance. Override this in a subclass if you want to
control the saving process.

The 'force_insert' and 'force_update' parameters can be used to insist
that the "save" must be an SQL insert or update (or equivalent for
non-SQL backends), respectively. Normally, they should not be set.

### Signature {#save-signature}

`save(self, kwargs)`

#### Parameters {#save-parameters}

| Name | Type | Required | Default | Description |
| --- | --- | --- | --- | --- |
| self |  | yes |  |  |
| <span id="save-param-kwargs">kwargs</span> |  | no |  |  |

### Source {#save-source}

`server/vueda/workflow/models.py:414`

## `events` {#events}

Accessor to the related objects manager on the reverse side of a
many-to-one relation.

In the example::

    class Child(Model):
        parent = ForeignKey(Parent, related_name='children')

``Parent.children`` is a ``ReverseManyToOneDescriptor`` instance.

Most of the implementation is delegated to a dynamically defined manager
class built by ``create_reverse_many_to_one_manager()`` defined below.

## `permission` {#permission}

Accessor to the related object on the forward side of a many-to-one or
one-to-one (via ForwardOneToOneDescriptor subclass) relation.

In the example::

    class Child(Model):
        parent = ForeignKey(Parent, related_name='children')

``Child.parent`` is a ``ForwardManyToOneDescriptor`` instance.

## `permission_id` {#permission_id}

## `pgh_event_models` {#pgh_event_models}

## `transition` {#transition}

Accessor to the related object on the forward side of a many-to-one or
one-to-one (via ForwardOneToOneDescriptor subclass) relation.

In the example::

    class Child(Model):
        parent = ForeignKey(Parent, related_name='children')

``Child.parent`` is a ``ForwardManyToOneDescriptor`` instance.

## `transition_id` {#transition_id}

## Source

`server/vueda/workflow/models.py:354`