Added option to bulk create vouchers via the WebUI.

Closes #9

community_backup/webui/admin.py

@@ -1,7 +1,50 @@
 from django.contrib import admin
+from django.urls import path, reverse_lazy
+from django.views.generic import FormView
+from django import forms
 
 from .models import BorgRepository, Voucher
 
+
+class VoucherBulkCreateForm(forms.Form):
+    prefix = forms.CharField(label="Voucher prefix")
+    amount = forms.IntegerField(label="Amount")
+
+
+class VoucherBulkCreateView(FormView):
+    form_class = VoucherBulkCreateForm
+    template_name = "admin/bulk_generate.html"
+    admin_site_context = None
+    success_url = reverse_lazy("admin:webui_voucher_changelist")
+
+    def get_context_data(self, **kwargs):
+        context = super().get_context_data(**kwargs)
+        # inject the admin site context so that the navbar and other things work as intended
+        context.update(self.admin_site_context.each_context(self.request))
+        return context
+
+    def form_valid(self, form):
+        Voucher.bulk_generate(form.cleaned_data["prefix"], form.cleaned_data["amount"])
+        return super().form_valid(form)
+
+
+@admin.register(Voucher)
+class VoucherAdmin(admin.ModelAdmin):
+    change_list_template = "admin/voucher_change_list.html"
+
+    def get_urls(self):
+        urls = super().get_urls()
+        my_urls = [
+            path(
+                "bulk_generate/",
+                self.admin_site.admin_view(
+                    VoucherBulkCreateView.as_view(admin_site_context=self.admin_site)
+                ),
+                name="voucher_bulk_generate",
+            )
+        ]
+        return my_urls + urls
+
+
 # Register your models here.
 admin.site.register(BorgRepository)
-admin.site.register(Voucher)