Django：解除用户分配后如何重定向至带Usecase ID的详情页

现有两个视图：

• view_usecase_details(request, ucid)：接收用例ID（ucid）参数，负责展示该用例的已分配用户列表，处理分配新用户的POST请求，渲染UsecaseDetails.html模板。
• unassign_emp(request, eid)：接收用户邮箱（eid）参数，负责从UsecaseAssign表中删除指定用户的关联记录。

当前需求是解除用户分配后，重定向回对应用例的详情页面，但解除分配视图无法获取并传递ucid参数，导致无法正确重定向。

相关代码 #

模型代码 #

class User(models.Model):
   user_email = models.CharField(primary_key=True, max_length=100)
   user_role_id = models.CharField(max_length=20)
   user_password = models.CharField(max_length=20)
   user_name = models.CharField(max_length=100)

class Usecase(models.Model):
   usecase_id = models.CharField(primary_key=True, max_length=20)
   usecase_name = models.CharField(max_length=256)
   user_email = models.ForeignKey('User', models.DO_NOTHING, db_column='user_email')
   usecase_type = models.ForeignKey('UsecaseType', models.DO_NOTHING)

class UsecaseAssign(models.Model):
   usecase_assign_date = models.DateTimeField(primary_key=True, auto_now_add=True)
   usecase = models.ForeignKey(Usecase, models.DO_NOTHING)
   user_email = models.ForeignKey('User', models.DO_NOTHING, db_column='user_email')
   usecase_role_id = models.CharField(max_length=20)

视图代码 #

@user_login_required
def view_usecase_details(request, ucid):
   usecase_details = Usecase.objects.filter(usecase_id=ucid).all()
   usecase_details = usecase_details.prefetch_related("usecaseids")
   users = User.objects.all()
   usecase_assigned = UsecaseAssign.objects.select_related('user_email').values_list('user_email__user_name').filter(usecase_id=ucid)
   user_assigned = UsecaseAssign.objects.values_list('user_email').filter(usecase_id=ucid)

   if request.method=='POST' and 'assignuser' in request.POST:
       user_email = request.POST['user_email']
       userAssignCheck = UsecaseAssign.objects.filter(user_email=user_email, usecase_id=ucid)
       if userAssignCheck:
           messages.error(request, "user already added!")
           return HttpResponseRedirect(reverse('usecase-details', args=[ucid]))
       else:
           userAssignObj = UsecaseAssign.objects.create(user_email_id=user_email, usecase_id=ucid)

       if userAssignObj:    
           messages.success(request, "User was Successfully Assigned with Usecase!")
           return HttpResponseRedirect(reverse('usecase-details', args=[ucid]))

   context = {'usecase_details': usecase_details, "users": User.objects.all(), 'usecase_assigned':usecase_assigned, "users": users, "user_assigned": user_assigned}
   return render(request, 'UsecaseDetails.html', context)   

@user_login_required
def unassign_emp(request, eid):
   if request.method=='POST' and 'unassign_emp' in request.POST:
       unassign_emp = UsecaseAssign.objects.get(user_email=eid)
       unassign_emp.delete()
       messages.success(request, "User was unassigned with Usecase!")
   return redirect('usecase-details') # 此处无法传递ucid参数

模板代码 #

{% for result in usecase_details %}
<div class="card card-body shadow-sm mb-4 mb-lg-0">
    <form class="mb-card" action="{% url 'usecase-details' ucid=result.usecase_id %}" method="POST">
        {% csrf_token %}
        <div class="form-row mb-4">
          <div class="col-lg-8 mr-f">
            <label class="h5" for="user_email">Assign new users:</label>
            <select name="user_email" class="custom-select my-1 mr-sm-2" id="user">
                <option value="0" selected>Select</option>
                {% for user in users %}
                <option value="{{ user.user_email }}">{{ user.user_name }}</option>
                {% endfor %}
              </select>
            </div>
        </div>
        <input type="submit" class="btn btn-primary" name="assignuser" value="Submit Changes">
      </form>
      <ul class="list-group list-group-flush">
        <li class="list-group-item d-flex align-items-center justify-content-between px-0 border-bottom">
            <div>
                <label class="mb-card h5" for="user_email">Assigned users:</label>
                {% for user in usecase_assigned %}
                <p>{{user|join:', '}}</p>
                {% endfor %}
                {% for unassign in user_assigned %}
                <form action="{% url 'unassign_emp' unassign %}" method="POST" style="display: inline !important;">
                    {% csrf_token %}
                    <input type="submit" class="btn btn-primary" name="unassign_emp" value="Delete">
                  </form>
                  {% endfor %}
            </div>
            </div>
        </li>
    </ul>
</div>
{% endfor %}

URL配置 #

path('usecase-details/<str:ucid>', av.view_usecase_details, name="usecase-details"),
    path('unassign-emp/<str:eid>/', av.unassign_emp, name="unassign_emp"),

解决方案 #

1. 修改URL配置，添加ucid参数 #

更新解除分配的URL，使其同时接收用户邮箱和用例ID：

path('unassign-emp/<str:eid>/<str:ucid>/', av.unassign_emp, name="unassign_emp"),

2. 更新模板表单，传递ucid #

在模板的解除分配表单中，将当前用例ID传递给URL：

{% for unassign in user_assigned %}
<form action="{% url 'unassign_emp' unassign result.usecase_id %}" method="POST" style="display: inline !important;">
    {% csrf_token %}
    <input type="submit" class="btn btn-primary" name="unassign_emp" value="Delete">
</form>
{% endfor %}

3. 修改视图函数，接收ucid并完成重定向 #

更新unassign_emp视图，接收ucid参数，删除对应记录后重定向到用例详情页，同时优化删除逻辑避免异常：

@user_login_required
def unassign_emp(request, eid, ucid):
    if request.method=='POST' and 'unassign_emp' in request.POST:
        # 过滤指定用户和用例的关联记录，避免误删其他用例的分配
        UsecaseAssign.objects.filter(user_email=eid, usecase_id=ucid).delete()
        messages.success(request, "User was unassigned with Usecase!")
    return redirect('usecase-details', ucid=ucid)

内容的提问来源于stack exchange，提问作者JHS99