Handle multiple flash messages on same key

lib/phoenix/controller/flash.ex

@@ -53,7 +53,8 @@ defmodule Phoenix.Controller.Flash do
 
   """
   def put(conn, key, message) do
-    persist(conn, put_in(get(conn), [key], message))
+    messages = [message] ++ get_all(conn, key)
+    persist(conn, put_in(get(conn), [key], messages))
   end
 
   @doc """
@@ -69,7 +70,28 @@ defmodule Phoenix.Controller.Flash do
   """
   def get(conn), do: get_session(conn, :phoenix_messages) || %{}
   def get(conn, key) do
-    get_in get(conn), [key]
+     case get_in get(conn), [key] do
+      nil -> nil
+      [message | _messages] -> message
+    end
+  end
+
+  @doc """
+  Returns a list of messages from the Flash
+
+  ## Examples
+
+      iex> conn
+      iex> |> Flash.put(:notice, "Hello")
+      iex> |> Flash.put(:notice, "Hi!")
+      iex> |> Flash.get
+      %{notice: ["hello", "world"]
+
+  """
+  def get_all(conn), do: get_session(conn, :phoenix_messages) || %{}
+  def get_all(conn, key) do
+    messages = get_in(get(conn), [key]) || []
+    Enum.reverse messages
   end
 
   @doc """
@@ -91,6 +113,27 @@ defmodule Phoenix.Controller.Flash do
     {message, conn}
   end
 
+  @doc """
+  Removes all messages from the Flash, returning a {messages, conn} pair
+
+  ## Examples
+
+      iex> %Conn{}
+      iex> |> Flash.put(:notices, "oh noes!")
+      iex> |> Flash.put(:notice, "false alarm!")
+      iex> |> Flash.pop_all(:notices) |> elem(0)
+      ["oh noes!", "false alarm!"]
+
+  """
+  def pop_all(conn, key) do
+    messages = get_all(conn, key)
+    if messages do
+      conn = persist(conn, Dict.drop(get(conn), [key]))
+    end
+
+    {messages, conn}
+  end
+
   @doc """
   Clears all flash messages
   """

test/phoenix/controller/flash_test.exs

@@ -57,19 +57,39 @@ defmodule Phoenix.Controller.FlashTest do
 
   test "get/1 returns the map of messages" do
     conn = conn_with_session |> Flash.put(:notice, "hi")
-    assert Flash.get(conn) == %{notice: "hi"}
+    assert Flash.get(conn) == %{notice: ["hi"]}
   end
 
   test "get/2 returns the message by key" do
     conn = conn_with_session |> Flash.put(:notice, "hi")
     assert Flash.get(conn, :notice) == "hi"
   end
 
+  test "get/2 returns the only the last message put" do
+    conn = conn_with_session
+    |> Flash.put(:notice, "hi")
+    |> Flash.put(:notice, "bye")
+    assert Flash.get(conn, :notice) == "bye"
+  end
+
   test "get/2 returns nil for missing key" do
     conn = conn_with_session
     assert Flash.get(conn, :notice) == nil
   end
 
+  test "get_all/2 returns a list of messages by key" do
+    conn = conn_with_session
+    |> Flash.put(:notices, "hello")
+    |> Flash.put(:notices, "world")
+
+    assert Flash.get_all(conn, :notices) == ["hello", "world"]
+  end
+
+  test "get_all/2 returns [] for missing key" do
+    conn = conn_with_session
+    assert Flash.get_all(conn, :notices) == []
+  end
+
   test "put/3 adds the key/message pair to the flash" do
     conn = conn_with_session
     |> Flash.put(:error, "oh noes!")
@@ -96,11 +116,21 @@ defmodule Phoenix.Controller.FlashTest do
 
     {message, conn} = Flash.pop(conn, :error)
     assert message == "oh noes!"
-    assert Flash.get(conn) == %{notice: "false alarm!"}
+    assert Flash.get(conn) == %{notice: ["false alarm!"]}
 
     {message, conn} = Flash.pop(conn, :notice)
     assert message == "false alarm!"
     assert Flash.get(conn) == %{}
   end
+
+  test "pop_all/3 pops all messages from the flash" do
+    conn = conn_with_session
+    |> Flash.put(:notices, "oh noes!")
+    |> Flash.put(:notices, "false alarm!")
+
+    {messages, conn} = Flash.pop_all(conn, :notices)
+    assert messages == ["oh noes!", "false alarm!"]
+    assert Flash.get(conn) == %{}
+  end
 end