templatetags for acl that use models not instances

re2o/templatetags/acl.py

@@ -0,0 +1,170 @@
+# -*- mode: python; coding: utf-8 -*-
+# Re2o est un logiciel d'administration développé initiallement au rezometz. Il
+# se veut agnostique au réseau considéré, de manière à être installable en
+# quelques clics.
+#
+# Copyright © 2017  Maël Kervella
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+"""
+Set of templatags for using acl in templates:
+    - can_create
+    - cannot_create
+
+**Parameters**:
+    model_name - The model_name that needs to be checked for the current user
+
+**Usage**:
+    {% <acl_name> model %}
+    <template stuff>
+    [{% can_else %}
+    <template stuff>]
+    {% can_end %}
+
+    where <acl_name> is one of the templatetag names available
+    (can_xxx or cannot_xxx)
+
+**Example**:
+    {% can_create Machine %}
+    <p>I'm authorized to create new machines \o/</p>
+    {% can_else %}
+    <p>Why can't I create a little machine :(</p>
+    {% can_end %}
+
+"""
+
+from django import template
+from django.template.base import Node, NodeList
+
+import cotisations.models as cotisations
+import logs.models as logs
+import machines.models as machines
+import topologie.models as topologie
+import users.models as users
+
+register = template.Library()
+
+
+def get_model(model_name):
+    # cotisations
+        # TODO
+    # logs
+        # TODO
+    # machines
+    if model_name == 'Machine':
+        return machines.Machine
+    elif model_name == 'MachineType':
+        return machines.MachineType
+    elif model_name == 'IpType':
+        return machines.IpType
+    elif model_name == 'Vlan':
+        return machines.Vlan
+    elif model_name == 'Nas':
+        return machines.Nas
+    elif model_name == 'SOA':
+        return machines.SOA
+    elif model_name == 'Extension':
+        return machines.Extension
+    elif model_name == 'Mx':
+        return machines.Mx
+    elif model_name == 'Ns':
+        return machines.Ns
+    elif model_name == 'Txt':
+        return machines.Txt
+    elif model_name == 'Srv':
+        return machines.Srv
+    elif model_name == 'Interface':
+        return machines.Interface
+    elif model_name == 'Domain':
+        return machines.Domain
+    elif model_name == 'IpList':
+        return machines.IpList
+    elif model_name == 'Service':
+        return machines.Service
+    elif model_name == 'Service_link':
+        return machines.Service_link
+    elif model_name == 'OuverturePortList':
+        return machines.OuverturePortList
+    elif model_name == 'OuverturePort':
+        return machines.OuverturePort
+    # topologie
+        # TODO
+    # users
+        # TODO
+    else:
+        raise template.TemplateSyntaxError(
+            "%r is not a valid model for %r tag" % model_name, tag_name
+        )
+
+
+def get_callback(tag_name, model_name):
+    model = get_model(model_name)
+
+    if tag_name == 'can_create':
+        return model.can_create
+    if tag_name == 'cannot_create':
+        def res(*args, **kwargs):
+            can, msg = model.can_create(*args, **kwargs)
+            return not can, msg
+        return res
+    else:
+        raise template.TemplateSyntaxError(
+            "%r tag is not a valid can_xxx tag" % tag_name
+        )
+
+
+@register.tag('can_create')
+@register.tag('cannot_create')
+def can_generic(parser, token):
+
+    try:
+        tag_name, model_name = token.split_contents()
+    except ValueError:
+        raise template.TemplateSyntaxError(
+            "%r tag require a single argument : the model" % token.contents.split()[0]
+        )
+
+    callback = get_callback(tag_name, model_name)
+
+    # {% can_create %}
+    oknodes = parser.parse(('can_else', 'can_end'))
+    token = parser.next_token()
+
+    # {% can_create_else %}
+    if token.contents == 'can_else':
+        konodes = parser.parse(('can_end'))
+        token = parser.next_token()
+    else:
+        konodes = NodeList()
+
+    # {% can_create_end %}
+    assert token.contents == 'can_end'
+
+    return CanNode( callback, oknodes, konodes )
+
+
+class CanNode(Node):
+
+    def __init__(self, callback, oknodes, konodes):
+        self.callback = callback
+        self.oknodes = oknodes
+        self.konodes = konodes
+
+    def render(self, context):
+        can, _ = self.callback(context['user'])
+        if can:
+            return self.oknodes.render(context)
+        return self.konodes.render(context)