Merge 2c011d1 into ff7065f

README.rst

@@ -50,6 +50,40 @@ Current features
 * **template tags**: tag templates to automate different types of auto-configurations (eg: mesh, WDS, 4G)
 * **simple HTTP resources**: allow devices to automatically download configuration updates
 * **VPN management**: easily create VPN servers and clients
+* **Template variables**: makes it possible to declare context (configuration variables) in template configuration while setting the default values for these declared context in the default values field to bypass validation.
+
+we can create a configuration in advanced mode with the following:
+
+.. code-block:: python
+
+        {
+            "interfaces": [
+                {
+                    "type": "ethernet",
+                    "name": "eth1",
+                    "mtu": 1500,
+                    "mac": "{{mac}}",
+                    "autostart": true,
+                    "disabled": false,
+                    "addresses": [],
+                    "network": ""
+                }
+            ]
+        }
+
+with the configuration above, we will need to set our default values field with the following
+json value specifying a default value for the `{{mac}}` variable.
+
+.. code-block:: python
+
+    {
+        "mac": "00:0a:95:9d:68:17"
+    }
+
+**note**: the following condition must be met for us to pass the validation:
+    - default_values must be a valid json
+    - values in default_values must be correctly set in JSON format
+    - default values must be set for all declared variables.
 
 Project goals
 -------------

django_netjsonconfig/base/admin.py

@@ -370,6 +370,7 @@ class AbstractTemplateAdmin(BaseConfigAdmin):
         'vpn',
         'auto_cert',
         'tags',
+        'default_values',
         'default',
         'config',
         'created',

django_netjsonconfig/base/base.py

@@ -148,15 +148,21 @@ def get_backend_instance(self, template_instances=None):
         """
         backend = self.backend_class
         kwargs = {'config': self.get_config()}
+        context = {}
         # determine if we can pass templates
         # expecting a many2many relationship
         if hasattr(self, 'templates'):
             if template_instances is None:
                 template_instances = self.templates.all()
-            kwargs['templates'] = [t.config for t in template_instances]
+            templates_list = list()
+            for t in template_instances:
+                templates_list.append(t.config)
+                context.update(t.get_context())
+            kwargs['templates'] = templates_list
         # pass context to backend if get_context method is defined
         if hasattr(self, 'get_context'):
-            kwargs['context'] = self.get_context()
+            context.update(self.get_context())
+            kwargs['context'] = context
         backend_instance = backend(**kwargs)
         # remove accidentally duplicated files when combining config and templates
         # this may happen if a device uses multiple VPN client templates

django_netjsonconfig/base/template.py

@@ -1,10 +1,12 @@
+from collections import OrderedDict
 from copy import copy
 
 from django.contrib.admin.models import ADDITION, LogEntry
 from django.contrib.contenttypes.models import ContentType
 from django.core.exceptions import ValidationError
 from django.db import models
 from django.utils.translation import ugettext_lazy as _
+from jsonfield import JSONField
 from taggit.managers import TaggableManager
 
 from ..settings import DEFAULT_AUTO_CERT
@@ -73,6 +75,19 @@ class AbstractTemplate(BaseConfig):
             'valid only for the VPN type'
         ),
     )
+    default_values = JSONField(
+        _('Default Values'),
+        default=dict,
+        blank=True,
+        help_text=_(
+            'A dictionary containing the default '
+            'values for the variables used by this '
+            'template; these default variables will '
+            'be used during schema validation.'
+        ),
+        load_kwargs={'object_pairs_hook': OrderedDict},
+        dump_kwargs={'indent': 4},
+    )
     __template__ = True
 
     class Meta:
@@ -114,7 +129,6 @@ def clean(self, *args, **kwargs):
         * clears VPN specific fields if type is not VPN
         * automatically determines configuration if necessary
         """
-        super().clean(*args, **kwargs)
         if self.type == 'vpn' and not self.vpn:
             raise ValidationError(
                 {'vpn': _('A VPN must be selected when template type is "VPN"')}
@@ -124,14 +138,14 @@ def clean(self, *args, **kwargs):
             self.auto_cert = False
         if self.type == 'vpn' and not self.config:
             self.config = self.vpn.auto_client(auto_cert=self.auto_cert)
+        super().clean(*args, **kwargs)
 
     def get_context(self):
-        c = {
-            'id': str(self.id),
-            'name': self.name,
-        }
-        c.update(super().get_context())
-        return c
+        context = {}
+        if self.default_values:
+            context = copy(self.default_values)
+        context.update(super().get_context())
+        return context
 
     def clone(self, user):
         clone = copy(self)

django_netjsonconfig/migrations/0044_template_default_values.py

@@ -0,0 +1,27 @@
+# Generated by Django 3.0.4 on 2020-04-08 23:46
+
+import collections
+from django.db import migrations
+import jsonfield.fields
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('django_netjsonconfig', '0043_add_indexes_on_ip_fields'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='template',
+            name='default_values',
+            field=jsonfield.fields.JSONField(
+                blank=True,
+                default=dict,
+                dump_kwargs={'ensure_ascii': False, 'indent': 4},
+                help_text='A dictionary containing the default values for the variables used by this template; these default variables will be used during schema validation.',
+                load_kwargs={'object_pairs_hook': collections.OrderedDict},
+                verbose_name='Default Values',
+            ),
+        ),
+    ]