Django工作流(状态管理)

本文通过简单的例子比较了django状态管理扩展的使用，涵盖django-fsm,xworkflows,django_transitions以及参考

django-fsm 使用例子

https://github.com/viewflow/django-fsm

state = FSMField(
    default=State.DRAFT,
    verbose_name='Publication State',
    choices=State.CHOICES,
    protected=True,
)
@transition(field=state, source=[State.APPROVED, State.EXPIRED],
    target=State.PUBLISHED,
    conditions=[can_display])
def publish(self):
    '''
    Publish the object.
    '''
    email_the_team()
    update_sitemap()
    busta_cache()

django-fsm-admin

https://github.com/gadventures/django-fsm-admin

from fsm_admin.mixins import FSMTransitionMixin

class YourModelAdmin(FSMTransitionMixin, admin.ModelAdmin):
    # The name of one or more FSMFields on the model to transition
    fsm_field = ['state',]
    readonly_fields = ['state', ]

admin.site.register(YourModel, YourModelAdmin)

xworkflows

https://github.com/rbarrois/xworkflows

import xworkflows

class MyWorkflow(xworkflows.Workflow):
    # A list of state names
    states = (
        ('foo', "Foo"),
        ('bar', "Bar"),
        ('baz', "Baz"),
    )
    # A list of transition definitions; items are (name, source states, target).
    transitions = (
        ('foobar', 'foo', 'bar'),
        ('gobaz', ('foo', 'bar'), 'baz'),
        ('bazbar', 'baz', 'bar'),
    )
    initial_state = 'foo'

class MyObject(xworkflows.WorkflowEnabled):
    state = MyWorkflow()

    @xworkflows.transition()
    def foobar(self):
        return 42

    # It is possible to use another method for a given transition.
    @xworkflows.transition('gobaz')
    def blah(self):
        return 13

django_transitions

LiveStatus Status

class LiveStatus(StatusBase):
    """Workflow for Lifecycle."""

    # Define the states as constants
    DEVELOP = 'develop'
    LIVE = 'live'
    MAINTENANCE = 'maintenance'
    DELETED = 'deleted'

    # Give the states a human readable label
    STATE_CHOICES = (
        (DEVELOP, 'Under Development'),
        (LIVE, 'Live'),
        (MAINTENANCE, 'Under Maintenance'),
        (DELETED, 'Deleted'),
    )

    # Define the transitions as constants
    PUBLISH = 'publish'
    MAKE_PRIVATE = 'make_private'
    MARK_DELETED = 'mark_deleted'
    REVERT_DELETED = 'revert_delete'

    # Give the transitions a human readable label and css class
    # which will be used in the django admin
    TRANSITION_LABELS = {
        PUBLISH : {'label': 'Make live', 'cssclass': 'default'},
        MAKE_PRIVATE: {'label': 'Under maintenance'},
        MARK_DELETED: {'label': 'Mark as deleted', 'cssclass': 'deletelink'},
        REVERT_DELETED: {'label': 'Revert Delete', 'cssclass': 'default'},
    }

    # Construct the values to pass to the state machine constructor

    # The states of the machine
    SM_STATES = [
        DEVELOP, LIVE, MAINTENANCE, DELETED,
    ]

    # The machines initial state
    SM_INITIAL_STATE = DEVELOP

    # The transititions as a list of dictionaries
    SM_TRANSITIONS = [
        # trigger, source, destination
        {
            'trigger': PUBLISH,
            'source': [DEVELOP, MAINTENANCE],
            'dest': LIVE,
        },
        {
            'trigger': MAKE_PRIVATE,
            'source': LIVE,
            'dest': MAINTENANCE,
        },
        {
            'trigger': MARK_DELETED,
            'source': [
                DEVELOP, LIVE, MAINTENANCE,
            ],
            'dest': DELETED,
        },
        {
            'trigger': REVERT_DELETED,
            'source':  DELETED,
            'dest': MAINTENANCE,
        },
    ]

Model:

class Lifecycle(LifecycleStateMachineMixin, models.Model):
    """
    A model that provides workflow state and workflow date fields.

    This is a minimal example implementation.
    """

    class Meta:  # noqa: D106
        abstract = False

    wf_state = models.CharField(
        verbose_name = 'Workflow Status',
        null=False,
        blank=False,
        default=LiveStatus.SM_INITIAL_STATE,
        choices=LiveStatus.STATE_CHOICES,
        max_length=32,
        help_text='Workflow state',
    )

    wf_date =  models.DateTimeField(
        verbose_name = 'Workflow Date',
        null=False,
        blank=False,
        default=timezone.now,
        help_text='Indicates when this workflowstate was entered.',
    )

Admin

# -*- coding: utf-8 -*-
"""Example django admin."""

from django_transitions.admin import WorkflowAdminMixin
from django.contrib import admin

from .models import Lifecycle

class LifecycleAdmin(WorkflowAdminMixin, admin.ModelAdmin):
    """
    Minimal Admin for Lifecycles Example.

    You probably want to make the workflow fields
    read only so yo can not change these values
    manually.

    readonly_fields = ['wf_state', 'wf_date']
    """

    list_display = ['wf_date', 'wf_state']
    list_filter = ['wf_state']

admin.site.register(Lifecycle, LifecycleAdmin)

参考