【问题标题】：Django-MPTT full path to child pages how to make?Django-MPTT子页面的完整路径如何制作？
【发布时间】：2012-05-05 09:51:43
【问题描述】：

我开始使用 Django-MPTT 应用程序在我的 Django 站点页面上获取基于树的方法。

例如。我有带有子页面的页面：

恍惚：

Vocal Trance（子页面）
Hard Trance（子页面）

休息：

Atmo Breaks（子页面）
渐进式休息（子页面）

如何从 urls.py 访问它们？什么模式会有所帮助？我需要将 Full_path 存储在模型中还是可以通过 url 模式完成？

【问题讨论】：

标签： django-urls django-mptt

【解决方案1】：

我假设你的意思是你想做这样的 URL：

/trance/
/trance/vocal-trance/
/trance/hard-trace/
/breaks/
/breaks/atmo-breaks/
/breaks/progressive-breaks/

如果是这样，最好将 url 片段存储在模型中。比如：

from mptt.models import MPTTModel
from django.db import models
from django.template.defaultfilters import slugify

class Page(MPTTModel):
    name = models.CharField(max_length=50)
    slug = models.CharField(max_length=50,null=True)
    url = models.CharField(max_length=255,null=True)

    def save(self, *args, **kwargs)
        if self.slug is None:
            # create a slug that's unique to siblings
            slug = slugify(self.name)
            self.slug = slug
            siblings = self.get_siblings()
            i = 1
            while siblings.filter(slug=self.slug).exists():
                i += 1
                self.slug = slug + '-%d' % i

            # now create a URL based on parent's url + slug
            if self.parent:
                self.url = '%s/%s' % (self.parent.url, self.slug)
            else:
                self.url = self.slug
        super(Page, self).save(*args, **kwargs)

然后添加一个 URL 模式：

(r'^pages/(?P<page_url>[\w\d_/-]+)/$', 'pages.views.show_page'),

在您看来，您只需获取正确的页面：

def show_page(request, page_url=None):
    page = get_object_or_404(Page, url=page_url)
    ...

【讨论】：

当你修改一个根/分支 slug 并且需要更新后代 url 时怎么办？

【解决方案2】：

感谢您关注我的问题。看看，我最后是怎么做到的。

models.py

class WebPage(MPTTModel):

    slug=RuSlugField(max_length=20,unique=True)
    title=models.CharField(max_length=50)
    content=models.TextField()
    parent=TreeForeignKey('self',null=True,blank=True,related_name='children')

    class MPTTMeta:
        order_insertion_by=['slug']

    def get_absolute_url(self):#TODO:: replace with get_ancestors
        url = "/%s/" % self.slug
        page = self
        while page.parent:
            url = "/%s%s" % (page.parent.slug,url)
            page = page.parent
        return url

urls.py

urlpatterns = patterns('website.views',
    url(r"^add/$", "add_page",name="add"),
    url(r"^(?P<full_slug>.*)/add/$", "add_page",name="add"),
    url(r"^(?P<full_slug>.*)/edit/$", "edit_page",name="edit"),
    url(r'^$', ListView.as_view(model=WebPage,template_name='index.html',context_object_name="webpages_list",),name='index'),
    url(r"^(?P<full_slug>.*)/$", "page", name="page"),
)

views.py

def page(request, full_slug):

    # Make a list from full_slug.
    # For ex. /trance/progressive_trance/fonarev -> ['trance','progressive_trance','fonarev']
    slugs=full_slug.split('/')

    page=None

    # Get a page by it's slug
    if len(slugs)>1:
        page=get_object_or_404(WebPage,slug=slugs[-1])#slugs=['trance','vocal_trance'] -> 'vocal_trance'
    elif len(slugs)==1:
        page=get_object_or_404(WebPage,slug=slugs[0])#slugs=['trance'] -> 'trance'

    # Check if page url matches requested full_slug
    if page.get_absolute_url().strip('/') == full_slug:
        return render_to_response('page.html', {'page': page},context_instance=RequestContext(request))
    else:
        raise Http404

def edit_page(request,full_slug):
    slugs=full_slug.split('/')
    page=None

    if len(slugs)>1:
        page=get_object_or_404(WebPage,slug=slugs[-1])
    elif len(slugs)==1:
        page=get_object_or_404(WebPage,slug=slugs[0])

    if not page.get_absolute_url().strip('/') == full_slug:
        raise Http404

    # Send POST data for update an existing page.Update a page.
    if request.method=='POST':
        form=WebPageForm(request.POST, instance=page)
        if form.is_valid():
            form.save()
        return HttpResponseRedirect(page.get_absolute_url())

    # Render a form to edit data for existing page
    else:
        form=WebPageForm(instance=page)

    return render_to_response('edit_page.html',{'form':form,},context_instance=RequestContext(request))

def add_page(request,full_slug=None):
    parent_page=None
    slug=None

    if full_slug:
        slug=full_slug.split('/')

    # If there is a slug in REQUEST(ex.'trance')->we need to add a new_page to her parent_page.
    # So get a parent page.
    if slug:
        if len(slug)>1:
            parent_page=get_object_or_404(WebPage,slug=slug[-1])
        elif len(slug)==1:
            parent_page=get_object_or_404(WebPage,slug=slug[0])

    # Create a new_page
    if request.method=='POST':
        form=WebPageForm(request.POST)
        if form.is_valid():
            new_page=form.save(commit=False)
            if parent_page:
                new_page.parent=parent_page
            new_page.save()
            return HttpResponseRedirect(new_page.get_absolute_url())

    # Return an unbounded form
    else:
        form=WebPageForm()

return render_to_response('add_page.html',{'form':form,},context_instance=RequestContext(request))

诀窍在于我们必须检查页面是否真的存在通过 full_slug 访问它：

if not page.get_absolute_url().strip('/') == full_slug:
            raise Http404

否则，只允许通过 slug 进行检查可能是错误的。

【讨论】：

【解决方案3】：

还有一个 django 应用程序可以为您完成工作：django-mptt-urls

【讨论】：

是的，将 'an app' 替换为 'a django app' 是一个非常值得的编辑！ anatoly techtonik，现在我会为你和@Forethinker 祈祷

【解决方案4】：

def get_absolute_url(self):
    return '/'.join([x['slug'] for x in self.get_ancestors(include_self=True).values()])

【讨论】：