django rest framework view with merged results from different object serializers - json

Question

having the following models
class TreeLifephase(DBordered):
name = models.CharField(max_length=200)
def __unicode__(self):
return self.name
class TreeWidth(DBordered):
name = models.CharField(max_length=200)
def __unicode__(self):
return self.name
and many more like this, that contain editable attributes of my Tree objects. For a select field on the UI I want to have all available treelifephases and treewidths with one query - to have a json result that looks something like
{
"treelifephases": [
{
"id": 1,
"name": "young"
},
{
"id": 2,
"name": "medium"
},
{
"id": 3,
"name": "old"
}
],
"treewidths": [
{
"id": 1,
"name": "10-20cm"
},
{
"id": 2,
"name": "21-30cm"
},
{
"id": 3,
"name": "31-40cm"
}
]
}
I have serializers for the Models at hand and it would be awesome to have a view that could just get a list of serializers to return a resultset like the above.

Answer 1

You can use SerializerMethodField and you need to create a model, in order to use model serializer.
class FullTree(serializers.ModelSerializer):
full_tree = serializers.SerializerMethodField()
class Meta:
model = FullTreeModel
fields = ('treewidth','lifephase')
get_full_tree(obj):
treewidth = obj.treewidths # get all your treewidth
lifephase = obj.lifephases# get all your lifephases
//build your tree with your serializers
return your_full_tree

Answer 2

I came up with a good solution for my use case which I claryfied in the question above:
1st: I wrote a Serializer that only gives me the id and the name
class IDNameSerializer(serializers.BaseSerializer):
def to_representation(self, obj):
return {
'id': obj.id,
'name': obj.name
}
2nd: I wrote a view that gives me the required json response with the help of the #api-view decorator from django-rest-framework
from rest_framework.decorators import api_view
from rest_framework.response import Response
#api_view(['GET'])
def tree_select(request):
result = {}
result['treelifephases'] = IDNameSerializer(TreeLifephase.objects.all(),many=True).data
result['treewidths'] = IDNameSerializer(TreeWidth.objects.all(),many=True).data
return Response(result)
Why I chose this as an answer:
Through use of #api_view decorator, we can still use permission classes and other sugar
It gives the json response in the required format
It is easy to alter when new fields might come there is only the view to be changed
I don't need a django model only for serialization
It is simple!