flows: export export/import functions in UI

passbook/admin/templates/administration/flow/import.html

@@ -0,0 +1,13 @@
+{% extends base_template|default:"generic/form.html" %}
+
+{% load i18n %}
+
+{% block above_form %}
+<h1>
+{% trans 'Import Flow' %}
+</h1>
+{% endblock %}
+
+{% block action %}
+{% trans 'Import Flow' %}
+{% endblock %}

passbook/admin/templates/administration/flow/list.html

@@ -20,6 +20,7 @@
             <div class="pf-c-toolbar__content">
                 <div class="pf-c-toolbar__bulk-select">
                     <a href="{% url 'passbook_admin:flow-create' %}?back={{ request.get_full_path }}" class="pf-c-button pf-m-primary" type="button">{% trans 'Create' %}</a>
+                    <a href="{% url 'passbook_admin:flow-import' %}?back={{ request.get_full_path }}" class="pf-c-button pf-m-secondary" type="button">{% trans 'Import' %}</a>
                 </div>
                 {% include 'partials/pagination.html' %}
             </div>
@@ -62,6 +63,7 @@
                         <a class="pf-c-button pf-m-secondary" href="{% url 'passbook_admin:flow-update' pk=flow.pk %}?back={{ request.get_full_path }}">{% trans 'Edit' %}</a>
                         <a class="pf-c-button pf-m-danger" href="{% url 'passbook_admin:flow-delete' pk=flow.pk %}?back={{ request.get_full_path }}">{% trans 'Delete' %}</a>
                         <a class="pf-c-button pf-m-secondary" href="{% url 'passbook_admin:flow-execute' pk=flow.pk %}?next={{ request.get_full_path }}">{% trans 'Execute' %}</a>
+                        <a class="pf-c-button pf-m-secondary" href="{% url 'passbook_admin:flow-export' pk=flow.pk %}?next={{ request.get_full_path }}">{% trans 'Export' %}</a>
                     </td>
                 </tr>
                 {% endfor %}
@@ -81,6 +83,7 @@
                     {% trans 'Currently no flows exist. Click the button below to create one.' %}
                 </div>
                 <a href="{% url 'passbook_admin:flow-create' %}?back={{ request.get_full_path }}" class="pf-c-button pf-m-primary" type="button">{% trans 'Create' %}</a>
+                <a href="{% url 'passbook_admin:flow-import' %}?back={{ request.get_full_path }}" class="pf-c-button pf-m-primary" type="button">{% trans 'Import' %}</a>
             </div>
         </div>
         {% endif %}

passbook/admin/templates/generic/form.html

@@ -30,7 +30,7 @@
         <div class="pf-l-stack__item">
             <div class="pf-c-card">
                 <div class="pf-c-card__body">
-                    <form action="" method="post" class="pf-c-form pf-m-horizontal">
+                    <form action="" method="post" class="pf-c-form pf-m-horizontal" enctype="multipart/form-data">
                         {% include 'partials/form_horizontal.html' with form=form %}
                         {% block beneath_form %}
                         {% endblock %}

passbook/admin/urls.py

@@ -191,6 +191,7 @@ urlpatterns = [
     # Flows
     path("flows/", flows.FlowListView.as_view(), name="flows"),
     path("flows/create/", flows.FlowCreateView.as_view(), name="flow-create",),
+    path("flows/import/", flows.FlowImportView.as_view(), name="flow-import",),
     path(
         "flows/<uuid:pk>/update/", flows.FlowUpdateView.as_view(), name="flow-update",
     ),
@@ -199,6 +200,9 @@ urlpatterns = [
         flows.FlowDebugExecuteView.as_view(),
         name="flow-execute",
     ),
+    path(
+        "flows/<uuid:pk>/export/", flows.FlowExportView.as_view(), name="flow-export",
+    ),
     path(
         "flows/<uuid:pk>/delete/", flows.FlowDeleteView.as_view(), name="flow-delete",
     ),

passbook/admin/views/flows.py

@@ -1,19 +1,22 @@
 """passbook Flow administration"""
+from django.contrib import messages
 from django.contrib.auth.mixins import LoginRequiredMixin
 from django.contrib.auth.mixins import (
     PermissionRequiredMixin as DjangoPermissionRequiredMixin,
 )
 from django.contrib.messages.views import SuccessMessageMixin
-from django.http import HttpRequest, HttpResponse
+from django.http import HttpRequest, HttpResponse, JsonResponse
 from django.urls import reverse_lazy
 from django.utils.translation import ugettext as _
-from django.views.generic import DetailView, ListView, UpdateView
+from django.views.generic import DetailView, FormView, ListView, UpdateView
 from guardian.mixins import PermissionListMixin, PermissionRequiredMixin
 
 from passbook.admin.views.utils import DeleteMessageView
-from passbook.flows.forms import FlowForm
+from passbook.flows.forms import FlowForm, FlowImportForm
 from passbook.flows.models import Flow
 from passbook.flows.planner import PLAN_CONTEXT_PENDING_USER
+from passbook.flows.transfer.exporter import FlowExporter
+from passbook.flows.transfer.importer import FlowImporter
 from passbook.flows.views import SESSION_KEY_PLAN, FlowPlanner
 from passbook.lib.utils.urls import redirect_with_qs
 from passbook.lib.views import CreateAssignPermView
@@ -88,3 +91,43 @@ class FlowDebugExecuteView(LoginRequiredMixin, PermissionRequiredMixin, DetailVi
         return redirect_with_qs(
             "passbook_flows:flow-executor-shell", self.request.GET, flow_slug=flow.slug,
         )
+
+
+class FlowImportView(LoginRequiredMixin, FormView):
+    """Import flow from JSON Export; only allowed for superusers
+    as these flows can contain python code"""
+
+    form_class = FlowImportForm
+    template_name = "administration/flow/import.html"
+    success_url = reverse_lazy("passbook_admin:flows")
+
+    def dispatch(self, request, *args, **kwargs):
+        if not request.user.is_superuser:
+            return self.handle_no_permission()
+        return super().dispatch(request, *args, **kwargs)
+
+    def form_valid(self, form: FlowImportForm) -> HttpResponse:
+        importer = FlowImporter(form.cleaned_data["flow"].read().decode())
+        successful = importer.apply()
+        if not successful:
+            messages.error(self.request, _("Failed to import flow."))
+        else:
+            messages.success(self.request, _("Successfully imported flow."))
+        return super().form_valid(form)
+
+
+class FlowExportView(LoginRequiredMixin, PermissionRequiredMixin, DetailView):
+    """Export Flow"""
+
+    model = Flow
+    permission_required = "passbook_flows.export_flow"
+
+    # pylint: disable=unused-argument
+    def get(self, request: HttpRequest, pk: str) -> HttpResponse:
+        """Debug exectue flow, setting the current user as pending user"""
+        flow: Flow = self.get_object()
+        exporter = FlowExporter(flow)
+        export = exporter.export_to_string()
+        response = JsonResponse(export)
+        response["Content-Disposition"] = f'attachment; filename="{flow.slug}.json"'
+        return response

passbook/flows/forms.py

@@ -1,9 +1,11 @@
 """Flow and Stage forms"""
 
 from django import forms
+from django.forms import ValidationError
 from django.utils.translation import gettext_lazy as _
 
 from passbook.flows.models import Flow, FlowStageBinding, Stage
+from passbook.flows.transfer.importer import FlowImporter
 from passbook.lib.widgets import GroupedModelChoiceField
 
 
@@ -53,3 +55,18 @@ class FlowStageBindingForm(forms.ModelForm):
         widgets = {
             "name": forms.TextInput(),
         }
+
+
+class FlowImportForm(forms.Form):
+    """Form used for flow importing"""
+
+    flow = forms.FileField()
+
+    def clean_flow(self):
+        """Check if the flow is valid and rewind the file to the start"""
+        flow = self.cleaned_data["flow"].read()
+        valid = FlowImporter(flow.decode()).validate()
+        if not valid:
+            raise ValidationError(_("Flow invalid."))
+        self.cleaned_data["flow"].seek(0)
+        return self.cleaned_data["flow"]

passbook/flows/models.py

@@ -135,6 +135,10 @@ class Flow(SerializerModel, PolicyBindingModel):
         verbose_name = _("Flow")
         verbose_name_plural = _("Flows")
 
+        permissions = [
+            ("export_flow", "Can export a Flow"),
+        ]
+
 
 class FlowStageBinding(SerializerModel, PolicyBindingModel):
     """Relationship between Flow and Stage. Order is required and unique for