perf: add InfiniteScroll on transfers page

apps/app/lib/app/transfers.ex

@@ -31,7 +31,13 @@ defmodule App.Transfers do
   @doc """
   Find all money transfers of a book.
 
-  The result may be filtered by passing a map of filters.
+  The result may be filtered by passing a options.
+
+  ## Options
+
+  - `:filters` - a map of filters to apply to the query. See the `Filters` section below.
+  - `:offset` - the offset of the query
+  - `:limit` - the limit of the query
 
   ## Filters
 
@@ -40,10 +46,15 @@ defmodule App.Transfers do
   - `:tenanted_by` - the tenancy of the transfer, one of :anyone, a member id or
     `{:not, member_id}`
   """
-  @spec list_transfers_of_book(Book.t(), map()) :: [MoneyTransfer.t()]
-  def list_transfers_of_book(%Book{} = book, filters \\ %{}) do
+  @spec list_transfers_of_book(Book.t(), Keyword.t()) :: [MoneyTransfer.t()]
+  def list_transfers_of_book(%Book{} = book, opts \\ []) do
+    filters = Keyword.get(opts, :filters, %{})
+    offset = Keyword.get(opts, :offset, 0)
+    limit = Keyword.get(opts, :limit, 25)
+
     MoneyTransfer.transfers_of_book_query(book)
     |> filter_money_transfers_query(filters)
+    |> paginate_query(offset, limit)
     |> Repo.all()
   end
 
@@ -118,6 +129,14 @@ defmodule App.Transfers do
         where: money_transfer.tenant_id == ^member_id
       )
 
+  ## Pagination
+
+  defp paginate_query(query, offset, limit) do
+    query
+    |> limit(^limit)
+    |> offset(^offset)
+  end
+
   ## Amount summary
 
   @typep amount_summary :: %{

apps/app/test/app/transfers_test.exs

@@ -15,7 +15,7 @@ defmodule App.TransfersTest do
   alias App.Transfers
   alias App.Transfers.Peer
 
-  describe "list_transfers_of_book/1" do
+  describe "list_transfers_of_book/2" do
     setup :book_with_member_context
 
     test "lists all transfers in book", %{book: book, member: member} do
@@ -29,15 +29,15 @@ defmodule App.TransfersTest do
       transfer1 = money_transfer_fixture(book, date: ~D[2020-06-29], tenant_id: member.id)
       transfer2 = money_transfer_fixture(book, date: ~D[2020-06-30], tenant_id: member.id)
 
-      assert Transfers.list_transfers_of_book(book, %{sort_by: :most_recent})
+      assert Transfers.list_transfers_of_book(book, filters: %{sort_by: :most_recent})
              |> Enum.map(& &1.id) == [transfer2.id, transfer1.id]
     end
 
     test "sorts by oldest", %{book: book, member: member} do
       transfer1 = money_transfer_fixture(book, date: ~D[2020-06-29], tenant_id: member.id)
       transfer2 = money_transfer_fixture(book, date: ~D[2020-06-30], tenant_id: member.id)
 
-      assert Transfers.list_transfers_of_book(book, %{sort_by: :oldest})
+      assert Transfers.list_transfers_of_book(book, filters: %{sort_by: :oldest})
              |> Enum.map(& &1.id) == [transfer1.id, transfer2.id]
     end
 
@@ -48,7 +48,7 @@ defmodule App.TransfersTest do
       transfer2 =
         money_transfer_fixture(book, inserted_at: ~N[2020-06-30 12:00:00], tenant_id: member.id)
 
-      assert Transfers.list_transfers_of_book(book, %{sort_by: :last_created})
+      assert Transfers.list_transfers_of_book(book, filters: %{sort_by: :last_created})
              |> Enum.map(& &1.id) == [transfer2.id, transfer1.id]
     end
 
@@ -59,7 +59,7 @@ defmodule App.TransfersTest do
       transfer2 =
         money_transfer_fixture(book, inserted_at: ~N[2020-06-30 12:00:00], tenant_id: member.id)
 
-      assert Transfers.list_transfers_of_book(book, %{sort_by: :first_created})
+      assert Transfers.list_transfers_of_book(book, filters: %{sort_by: :first_created})
              |> Enum.map(& &1.id) == [transfer1.id, transfer2.id]
     end
 
@@ -70,7 +70,7 @@ defmodule App.TransfersTest do
       member2 = book_member_fixture(book)
       transfer2 = money_transfer_fixture(book, tenant_id: member2.id)
 
-      assert Transfers.list_transfers_of_book(book, %{tenanted_by: :anyone})
+      assert Transfers.list_transfers_of_book(book, filters: %{tenanted_by: :anyone})
              |> Enum.map(& &1.id)
              |> Enum.sort() == [transfer1.id, transfer2.id]
     end
@@ -82,7 +82,7 @@ defmodule App.TransfersTest do
       member2 = book_member_fixture(book)
       _transfer2 = money_transfer_fixture(book, tenant_id: member2.id)
 
-      assert Transfers.list_transfers_of_book(book, %{tenanted_by: member1.id})
+      assert Transfers.list_transfers_of_book(book, filters: %{tenanted_by: member1.id})
              |> Enum.map(& &1.id) == [transfer1.id]
     end
 
@@ -93,9 +93,90 @@ defmodule App.TransfersTest do
       member2 = book_member_fixture(book)
       transfer2 = money_transfer_fixture(book, tenant_id: member2.id)
 
-      assert Transfers.list_transfers_of_book(book, %{tenanted_by: {:not, member1.id}})
+      assert Transfers.list_transfers_of_book(book, filters: %{tenanted_by: {:not, member1.id}})
              |> Enum.map(& &1.id) == [transfer2.id]
     end
+
+    test "paginates results", %{book: book, member: member} do
+      transfer1 = money_transfer_fixture(book, tenant_id: member.id, date: ~D[2020-06-29])
+      transfer2 = money_transfer_fixture(book, tenant_id: member.id, date: ~D[2020-06-30])
+
+      assert Transfers.list_transfers_of_book(book, offset: 0, limit: 1)
+             |> Enum.map(& &1.id) == [transfer2.id]
+
+      assert Transfers.list_transfers_of_book(book, offset: 1, limit: 1)
+             |> Enum.map(& &1.id) == [transfer1.id]
+
+      assert Transfers.list_transfers_of_book(book, offset: 0, limit: 25)
+             |> Enum.map(& &1.id) == [transfer2.id, transfer1.id]
+    end
+
+    test "paginated results are filtered and consistent", %{book: book} do
+      member1 = book_member_fixture(book)
+      member2 = book_member_fixture(book)
+
+      transfer1 = money_transfer_fixture(book, tenant_id: member1.id, date: ~D[2020-06-29])
+      _transfer2 = money_transfer_fixture(book, tenant_id: member1.id, date: ~D[2020-06-30])
+      transfer3 = money_transfer_fixture(book, tenant_id: member2.id, date: ~D[2020-06-28])
+
+      assert Transfers.list_transfers_of_book(book,
+               filters: %{tenanted_by: member2.id},
+               offset: 0,
+               limit: 25
+             )
+             |> Enum.map(& &1.id) == [transfer3.id]
+
+      assert Transfers.list_transfers_of_book(book,
+               filters: %{tenanted_by: {:not, member2.id}},
+               offset: 1,
+               limit: 25
+             )
+             |> Enum.map(& &1.id) == [transfer1.id]
+    end
+
+    test "paginated results are sorted and consistent", %{book: book, member: member} do
+      transfer1 =
+        money_transfer_fixture(book,
+          tenant_id: member.id,
+          date: ~D[2020-06-29],
+          inserted_at: ~N[2020-06-29 12:00:00]
+        )
+
+      transfer2 =
+        money_transfer_fixture(book,
+          tenant_id: member.id,
+          date: ~D[2020-06-30],
+          inserted_at: ~N[2020-06-30 12:00:00]
+        )
+
+      transfer3 =
+        money_transfer_fixture(book,
+          tenant_id: member.id,
+          date: ~D[2020-06-28],
+          inserted_at: ~N[2020-06-28 12:00:00]
+        )
+
+      assert Transfers.list_transfers_of_book(book,
+               filters: %{sort_by: :most_recent},
+               offset: 0,
+               limit: 25
+             )
+             |> Enum.map(& &1.id) == [transfer2.id, transfer1.id, transfer3.id]
+
+      assert Transfers.list_transfers_of_book(book,
+               filters: %{sort_by: :oldest},
+               offset: 2,
+               limit: 25
+             )
+             |> Enum.map(& &1.id) == [transfer2.id]
+
+      assert Transfers.list_transfers_of_book(book,
+               filters: %{sort_by: :last_created},
+               offset: 1,
+               limit: 25
+             )
+             |> Enum.map(& &1.id) == [transfer1.id, transfer3.id]
+    end
   end
 
   describe "list_transfers_of_members/1" do

apps/app_web/lib/app_web/live/book_balance_live.ex

@@ -71,7 +71,6 @@ defmodule AppWeb.BookBalanceLive do
       socket
       |> assign(
         page_title: "Balance · #{book.name}",
-        layout_heading: gettext("Balance"),
         current_transaction: nil
       )
       |> assign_transactions()

apps/app_web/lib/app_web/live/book_members_live.ex

@@ -84,11 +84,7 @@ defmodule AppWeb.BookMembersLive do
   def mount(_params, _session, socket) do
     book = socket.assigns.book
 
-    socket =
-      assign(socket,
-        page_title: book.name,
-        layout_heading: gettext("Details")
-      )
+    socket = assign(socket, page_title: book.name)
 
     {:ok, socket, layout: {AppWeb.Layouts, :book}}
   end