设置发布者

本课属于 Coddy Django 学习旅程的“基于类的视图”单元。第 15 课，共 18 课。

每个 Job 都有一个 posted_by 字段，新建的职位会将它留空。它不能是表单字段，否则任何人都可以冒用别人的名义发布职位。视图会填入这个字段。

表单有效时，编辑视图会调用 form_valid(form)，保存数据行并重定向。你可以重写它，先修改数据行。一个食谱网站会将每条评价保存到其 URL 中对应的食谱上，URL 为 recipes/<slug:slug>/review/：

class ReviewCreateView(LoginRequiredMixin, CreateView):
    model = Review
    fields = ["stars", "text"]

    def form_valid(self, form):
        recipe = get_object_or_404(Recipe, slug=self.kwargs["slug"])
        form.instance.recipe = recipe
        return super().form_valid(form)

form.instance 是尚未保存的数据行。self.kwargs 保存着 URL 参数；只有这个示例需要它来查找食谱。先设置你的字段，然后让 super().form_valid(form) 保存并重定向。如果在调用 super() 后才设置字段，数据行就已经在未设置该字段的情况下保存了。

挑战

简单

在 JobCreateView 中，重写 form_valid()，让新职位的 posted_by 设为已登录用户。不要把 posted_by 放进 fields。

以 grace（coddy-pass-123）的身份登录并发布一个职位：职位页面的日期后面会显示 by grace。

亲手试试

from django.contrib.auth.mixins import LoginRequiredMixin
from django.urls import reverse_lazy
from django.views.generic import CreateView, DeleteView, DetailView, ListView, TemplateView, UpdateView

from .models import Job


class HomeView(TemplateView):
    template_name = "jobs/home.html"

    def get_context_data(self, **kwargs):
        context = super().get_context_data(**kwargs)
        context["count"] = Job.objects.count()
        context["latest"] = Job.objects.order_by("-posted").first()
        return context


class AboutView(TemplateView):
    template_name = "jobs/about.html"


class JobListView(ListView):
    model = Job
    context_object_name = "jobs"
    ordering = ["-posted"]
    paginate_by = 5

    def get_queryset(self):
        jobs = super().get_queryset()
        city = self.request.GET.get("city")
        if city:
            jobs = jobs.filter(city=city)
        return jobs


class JobDetailView(DetailView):
    model = Job


class JobCreateView(LoginRequiredMixin, CreateView):
    model = Job
    fields = ["title", "company", "city", "salary", "description"]


class JobUpdateView(LoginRequiredMixin, UpdateView):
    model = Job
    fields = ["title", "company", "city", "salary", "description"]


class JobDeleteView(LoginRequiredMixin, DeleteView):
    model = Job
    success_url = reverse_lazy("jobs:list")