From 9c61f605582520368d61a31e562710f383fab9c1 Mon Sep 17 00:00:00 2001
From: Hakaba Hitoyo <example@example.com>
Date: Fri, 9 Feb 2018 21:41:30 +0900
Subject: [PATCH 1/4] introduce max_id parameter in feed.atom

---
 lib/pleroma/web/ostatus/ostatus_controller.ex | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/lib/pleroma/web/ostatus/ostatus_controller.ex b/lib/pleroma/web/ostatus/ostatus_controller.ex
index d442d16fd..203b6e985 100644
--- a/lib/pleroma/web/ostatus/ostatus_controller.ex
+++ b/lib/pleroma/web/ostatus/ostatus_controller.ex
@@ -25,6 +25,7 @@ def feed(conn, %{"nickname" => nickname}) do
       order_by: [desc: :id]
 
     activities = query
+    |> restrict_max(opts)    
     |> Repo.all
 
     response = user
@@ -54,6 +55,11 @@ defp decode_or_retry(body) do
     end
   end
 
+  defp restrict_max(query, %{"max_id" => max_id}) do
+    from activity in query, where: activity.id < ^max_id
+  end
+  defp restrict_max(query, _), do: query
+
   def salmon_incoming(conn, _) do
     {:ok, body, _conn} = read_body(conn)
     {:ok, doc} = decode_or_retry(body)

From 7124f12a94478206f600b93055e0a82b945de858 Mon Sep 17 00:00:00 2001
From: Hakaba Hitoyo <example@example.com>
Date: Fri, 9 Feb 2018 21:46:05 +0900
Subject: [PATCH 2/4] introduce max_id parameter in feed.atom (debug)

---
 lib/pleroma/web/ostatus/ostatus_controller.ex | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/pleroma/web/ostatus/ostatus_controller.ex b/lib/pleroma/web/ostatus/ostatus_controller.ex
index 203b6e985..4d48c5d2b 100644
--- a/lib/pleroma/web/ostatus/ostatus_controller.ex
+++ b/lib/pleroma/web/ostatus/ostatus_controller.ex
@@ -17,7 +17,7 @@ def feed_redirect(conn, %{"nickname" => nickname}) do
     end
   end
 
-  def feed(conn, %{"nickname" => nickname}) do
+  def feed(conn, %{"nickname" => nickname} = params) do
     user = User.get_cached_by_nickname(nickname)
     query = from activity in Activity,
       where: fragment("?->>'actor' = ?", activity.data, ^user.ap_id),
@@ -25,7 +25,7 @@ def feed(conn, %{"nickname" => nickname}) do
       order_by: [desc: :id]
 
     activities = query
-    |> restrict_max(opts)    
+    |> restrict_max(params)
     |> Repo.all
 
     response = user

From a61f21ff4f825bc11b9d1c7c23baa3d2820cd718 Mon Sep 17 00:00:00 2001
From: hakabahitoyo <hakabahitoyo@example.com>
Date: Fri, 9 Feb 2018 23:03:28 +0900
Subject: [PATCH 3/4] print <link rel="next"> element in atom.feed

---
 lib/pleroma/web/ostatus/feed_representer.ex | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/lib/pleroma/web/ostatus/feed_representer.ex b/lib/pleroma/web/ostatus/feed_representer.ex
index 10860ce04..8461b2b9f 100644
--- a/lib/pleroma/web/ostatus/feed_representer.ex
+++ b/lib/pleroma/web/ostatus/feed_representer.ex
@@ -10,6 +10,8 @@ def to_simple_form(user, activities, _users) do
 
     h = fn(str) -> [to_charlist(str)] end
 
+    last_activity = List.last(activities)
+
     entries = activities
     |> Enum.map(fn(activity) ->
       {:entry, ActivityRepresenter.to_simple_form(activity, user)}
@@ -32,7 +34,15 @@ def to_simple_form(user, activities, _users) do
         {:link, [rel: 'salmon', href: h.(OStatus.salmon_path(user))], []},
         {:link, [rel: 'self', href: h.(OStatus.feed_path(user)), type: 'application/atom+xml'], []},
         {:author, UserRepresenter.to_simple_form(user)},
-      ] ++ entries
+      ] ++
+      if last_activity do
+        [{:link, [rel: 'next',
+          href: to_charlist(OStatus.feed_path(user)) ++ '?max_id=' ++ to_charlist(last_activity.id),
+          type: 'application/atom+xml'], []}]
+      else
+        []
+      end
+      ++ entries
     }]
   end
 end

From 3c80d9b27764817fcfdc4f7663f36147a9411b61 Mon Sep 17 00:00:00 2001
From: lain <lain@soykaf.club>
Date: Mon, 12 Feb 2018 08:15:03 +0100
Subject: [PATCH 4/4] Fix spec.

---
 test/web/ostatus/feed_representer_test.exs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/test/web/ostatus/feed_representer_test.exs b/test/web/ostatus/feed_representer_test.exs
index e10936366..5b8eabcb9 100644
--- a/test/web/ostatus/feed_representer_test.exs
+++ b/test/web/ostatus/feed_representer_test.exs
@@ -33,6 +33,7 @@ test "returns a feed of the last 20 items of the user" do
       <author>
         #{user_xml}
       </author>
+      <link rel="next" href="#{OStatus.feed_path(user)}?max_id=#{note_activity.id}" type="application/atom+xml" />
       <entry>
         #{entry_xml}
       </entry>