+
+ @doc """
+ Fetches the OrderedCollection/OrderedCollectionPage from `from`, limiting the amount of pages fetched after
+ the first one to `pages_left` pages.
+ If the amount of pages is higher than the collection has, it returns whatever was there.
+ """
+ def fetch_ordered_collection(from, pages_left, acc \\ []) do
+ with {:ok, response} <- Tesla.get(from),
+ {:ok, collection} <- Poison.decode(response.body) do
+ case collection["type"] do
+ "OrderedCollection" ->
+ # If we've encountered the OrderedCollection and not the page,
+ # just call the same function on the page address
+ fetch_ordered_collection(collection["first"], pages_left)
+
+ "OrderedCollectionPage" ->
+ if pages_left > 0 do
+ # There are still more pages
+ if Map.has_key?(collection, "next") do
+ # There are still more pages, go deeper saving what we have into the accumulator
+ fetch_ordered_collection(
+ collection["next"],
+ pages_left - 1,
+ acc ++ collection["orderedItems"]
+ )
+ else
+ # No more pages left, just return whatever we already have
+ acc ++ collection["orderedItems"]
+ end
+ else
+ # Got the amount of pages needed, add them all to the accumulator
+ acc ++ collection["orderedItems"]
+ end
+
+ _ ->
+ {:error, "Not an OrderedCollection or OrderedCollectionPage"}
+ end
+ end
+ end