Resolve "configuration panel"

Closes #87 (closed)

smash/web/api_views/configuration.py

+from django.contrib.auth.decorators import login_required
+from django.http import JsonResponse
+
+from web.models import ConfigurationItem
+
+
+@login_required
+def configuration_items(request):
+    # id of the query from dataTable: https://datatables.net/manual/server-side
+    draw = int(request.GET.get("draw", "-1"))
+
+    start = int(request.GET.get("start", "0"))
+    length = int(request.GET.get("length", "10"))
+
+    items = ConfigurationItem.objects.all()
+    count = items.count()
+    count_filtered = count
+
+    sliced_items = items[start:(start + length)]
+
+    data = []
+    for configuration_item in sliced_items:
+        data.append({
+            "id": configuration_item.id,
+            "name": configuration_item.name,
+            "value": configuration_item.value
+        })
+    return JsonResponse({
+        "draw": draw,
+        "recordsTotal": count,
+        "recordsFiltered": count_filtered,
+        "data": data
+    })
+
+
+@login_required
+def update_configuration_item(request):
+    id = int(request.GET.get("id", "-1"))
+    value = request.GET.get("value", None)
+
+    if (id is None) or (value is None):
+        return JsonResponse({
+            "status": "error",
+            "message": "id and value are obligatory"
+        })
+
+    items = ConfigurationItem.objects.filter(id=id)
+    if len(items) == 0:
+        return JsonResponse({
+            "status": "error",
+            "message": "item with given id doesn't exist"
+        })
+    item = items[0]
+    item.value = value
+    item.save()
+    return JsonResponse({
+        "status": "ok",
+    })