sideposting - associating same newly created record with multiple records that are also being created

[akshah123]

I have a usecase with sidepost where I would multiple records to reference a new record that's being created.

An example setup would be:

class ModelA
  has_many :model_b
end

class ModelB
  belongs_to :model_a
  has_many :model_c
end

class ModelC
  belongs_to :model_b
  belongs_to :model_a
end

Now, i would like to create three object(s). 1 ModelA, 1 ModelB that belongs to ModelA and 1 ModelC that belongs to A & B.

I am trying following POST:

{
  "data": {
    "temp-id": "aaaa",
    "type": "model_a",
    "attributes": {
      "street_and_number": "test_model_a"
    },
    "relationships": {
      "model_b": {
        "data": [
          {
            "type": "model_b",
            "temp-id": "1a1a1a",
            "method": "create"
          }
        ]
      }
    }
  },
  "included": [
    {
      "type": "model_b",
      "temp-id": "1a1a1a",
      "attributes": {
        "name": "test location"
      },
      "relationships": {
        "model_c": {
          "data": [
            {
              "type": "model_c",
              "temp-id": "2b2b2b",
              "method": "create"
            }
          ]
        }
      }
    },
    {
      "type": "model_c",
      "temp-id": "2b2b2b",
      "attributes": {},
      "relationships": {
        "model_a": {
          "data": {
            "type": "model_a",
            "temp-id": "aaaa",
            "method": "create"
          }
        }
      }
    }
  ]
}

However, above setup seems to create duplicate records for ModelA. How would I set this up so that I am not creating duplicate records while keeping it a single API call?