Understand Data Factory Data Flow REST source behaviour when the response is json array

{
    "page": 2,
    "per_page": 6,
    "total": 12,
    "total_pages": 2,
    "data": [
        {
            "id": 7,
            "email": "email address removed for privacy reasons",
            "first_name": "Michael",
            "last_name": "Lawson",
            "avatar": "https://reqres.in/img/faces/7-image.jpg"
        },
        {
            "id": 8,
            "email": "email address removed for privacy reasons",
            "first_name": "Lindsay",
            "last_name": "Ferguson",
            "avatar": "https://reqres.in/img/faces/8-image.jpg"
        },
    ],
    "support": {
        "url": "https://reqres.in/#support-heading",
        "text": "To keep ReqRes free, contributions towards server costs are appreciated!"
    }
}

As you can see, the response payload is a Json Object with a data array containing the actual data content.

I need to unroll the data field and save it in a csv file using a Data Flow. That's pretty straightforward:

• Source Projection is defining a field named data of type complex array inside the body column: 
   

  

   
• Let's now unroll by data field and use an explicit mapping: 
   

  

• Just make data flow into the Sink with the auto-map feature: 
   

  

 Now, let's change our source, with a slightly different response (https://jsonplaceholder.typicode.com/posts)

[
  {
    "userId": 1,
    "id": 1,
    "title": "sunt aut facere repellat",
    "body": "quia et suscipit suscipit recusandae consequuntur expedita"
  },
  {
    "userId": 1,
    "id": 2,
    "title": "qui est esse",
    "body": "est rerum tempore vitae"
  },
  {
    "userId": 1,
    "id": 3,
    "title": "ea molestias",
    "body": "et iusto sed quo"
  },
  {
    "userId": 1,
    "id": 4,
    "title": "eum et est occaecati",
    "body": "ullam et saepe reiciendis voluptatem adipisci"
  }
]

In this case, the response body is just a Json Array. This particular detail, makes it impossible to reach the same goal as before.

• The projection shows the body which is defined as a complex object and not as a complex array as I would expect.

• In fact, unrolling data will be not allowed (the option is grayed out) 

   

  

• Also, trying to directly write the body field into a csv sink will result in a validation error: 

   

  

Eventually, I found a workaround where you should use the Aggregate task combined with the collect() function. But, it is just a lot of overhead.

I still think I'm missing something, but it seems that Data Factory Data Flows don't support Json Array object as a response payload from a REST source.