responseFields beneathPath array in array

[DriesCleymans]

I have a response with an array of objects, each objects contains a property with another array. It looks like this:

[ {
  "id" : 1,
  "name" : "Quick start",
  "type" : "radio",
  "musicChannels" : [ {
    "id" : 134,
    "name" : "Popular & Nostalgic",
    "musicChannelGroupId" : 1,
    "musicCollections" : "An array of MusicCollections"
  }, {
    "id" : 146,
    "name" : "Young & Alternative",
    "musicChannelGroupId" : 1,
    "musicCollections" : "An array of MusicCollections"
  } ]
}, {
  "id" : 2,
  "name" : "Create mood",
  "type" : "radio",
  "musicChannels" : [ {
    "id" : 146,
    "name" : "Popular & Nostalgic",
    "musicChannelGroupId" : 2,
    "musicCollections" : "An array of MusicCollections"
  } ]
}, {
  "id" : 3,
  "name" : "Discover more",
  "type" : "radio",
  "musicChannels" : [ {
    "id" : 146,
    "name" : "Young & Alternative",
    "musicChannelGroupId" : 3,
    "musicCollections" : "An array of MusicCollections"
  } ]
} ]

I want to document the object in the second array, and to generate a code snippet with restDocs, I am trying this:

responseBody(
	beneathPath("[0].musicChannels.[0]").withSubsectionId("musicChannel2")
)

But the output is:

[ {
  "id" : 134,
  "name" : "Popular & Nostalgic",
  "musicChannelGroupId" : 1,
  "musicCollections" : "An array of MusicCollections"
}, {
  "id" : 146,
  "name" : "Young & Alternative",
  "musicChannelGroupId" : 1,
  "musicCollections" : "An array of MusicCollections"
} ]

I want to have only the first object in the response body, but i fail with whatever I try to insert into 'beneathPath'.

So the question is: How to get the body for the first element in the array of a property in the first element in an array. I want this as a result:

{
  "id" : 134,
  "name" : "Popular & Nostalgic",
  "musicChannelGroupId" : 1,
  "musicCollections" : "An array of MusicCollections"
}

[wilkinsona]

Unfortunately, there's no support at the moment for specifying a specific index when drilling down into an array. #468 is tracking that enhancement.