From 5599c5920c293ac993146e21a73520213bbe2a8a Mon Sep 17 00:00:00 2001
From: Roger Braun <roger@rogerbraun.net>
Date: Mon, 11 Dec 2017 10:37:22 +0100
Subject: [PATCH] Basic incoming AP support.

---
 config/config.exs                             |  3 +-
 .../activity_pub/activity_pub_controller.ex   | 17 +++++++
 .../web/activity_pub/views/user_view.ex       | 51 +++++++++++++++++++
 lib/pleroma/web/ostatus/ostatus_controller.ex |  4 +-
 lib/pleroma/web/router.ex                     | 10 +++-
 5 files changed, 82 insertions(+), 3 deletions(-)
 create mode 100644 lib/pleroma/web/activity_pub/activity_pub_controller.ex
 create mode 100644 lib/pleroma/web/activity_pub/views/user_view.ex

diff --git a/config/config.exs b/config/config.exs
index c4f89c40c..f26f9ecdf 100644
--- a/config/config.exs
+++ b/config/config.exs
@@ -27,7 +27,8 @@
   metadata: [:request_id]
 
 config :mime, :types, %{
-  "application/xrd+xml" => ["xrd+xml"]
+  "application/xrd+xml" => ["xrd+xml"],
+  "application/activity+json" => ["activity+json"]
 }
 
 config :pleroma, :websub, Pleroma.Web.Websub
diff --git a/lib/pleroma/web/activity_pub/activity_pub_controller.ex b/lib/pleroma/web/activity_pub/activity_pub_controller.ex
new file mode 100644
index 000000000..738e4ba33
--- /dev/null
+++ b/lib/pleroma/web/activity_pub/activity_pub_controller.ex
@@ -0,0 +1,17 @@
+defmodule Pleroma.Web.ActivityPub.ActivityPubController do
+  use Pleroma.Web, :controller
+  alias Pleroma.{User, Repo}
+  alias Pleroma.Web.ActivityPub.UserView
+  alias Pleroma.Web.ActivityPub.ActivityPub
+
+  def user(conn, %{"nickname" => nickname}) do
+    with %User{} = user <- User.get_cached_by_nickname(nickname) do
+      json(conn, UserView.render("user.json", %{user: user}))
+    end
+  end
+
+  def inbox(conn, params) do
+    {:ok, activity} = ActivityPub.insert(params, false)
+    json(conn, "ok")
+  end
+end
diff --git a/lib/pleroma/web/activity_pub/views/user_view.ex b/lib/pleroma/web/activity_pub/views/user_view.ex
new file mode 100644
index 000000000..5303455a8
--- /dev/null
+++ b/lib/pleroma/web/activity_pub/views/user_view.ex
@@ -0,0 +1,51 @@
+defmodule Pleroma.Web.ActivityPub.UserView do
+  use Pleroma.Web, :view
+  alias Pleroma.Web.Salmon
+  alias Pleroma.User
+
+  def render("user.json", %{user: user}) do
+    {:ok, _, public_key} = Salmon.keys_from_pem(user.info["keys"])
+    public_key = :public_key.pem_entry_encode(:RSAPublicKey, public_key)
+    public_key = :public_key.pem_encode([public_key])
+    %{
+      "@context": [
+        "https://www.w3.org/ns/activitystreams",
+        "https://w3id.org/security/v1",
+        %{
+          "manuallyApprovesFollowers": "as:manuallyApprovesFollowers",
+          "sensitive": "as:sensitive",
+          "Hashtag": "as:Hashtag",
+          "ostatus": "http://ostatus.org#",
+          "atomUri": "ostatus:atomUri",
+          "inReplyToAtomUri": "ostatus:inReplyToAtomUri",
+          "conversation": "ostatus:conversation",
+          "toot": "http://joinmastodon.org/ns#",
+          "Emoji": "toot:Emoji"
+        }
+      ],
+      "id": user.ap_id,
+      "type": "Person",
+      "following": "#{user.ap_id}/following",
+      "followers": "#{user.ap_id}/followers",
+      "inbox": "#{user.ap_id}/inbox",
+      "outbox": "#{user.ap_id}/outbox",
+      "preferredUsername": user.nickname,
+      "name": user.name,
+      "summary": user.bio,
+      "url": user.ap_id,
+      "manuallyApprovesFollowers": false,
+      "publicKey": %{
+        "id": "#{user.ap_id}#main-key",
+        "owner": user.ap_id,
+        "publicKeyPem": public_key
+      },
+      "endpoints": %{
+        "sharedInbox": "#{Pleroma.Web.Endpoint.url}/inbox"
+      },
+      "icon": %{
+        "type": "Image",
+        "url": User.avatar_url(user)
+      }
+    }
+  end
+end
diff --git a/lib/pleroma/web/ostatus/ostatus_controller.ex b/lib/pleroma/web/ostatus/ostatus_controller.ex
index d442d16fd..778495a3e 100644
--- a/lib/pleroma/web/ostatus/ostatus_controller.ex
+++ b/lib/pleroma/web/ostatus/ostatus_controller.ex
@@ -6,13 +6,15 @@ defmodule Pleroma.Web.OStatus.OStatusController do
   alias Pleroma.Repo
   alias Pleroma.Web.{OStatus, Federator}
   alias Pleroma.Web.XML
+  alias Pleroma.Web.ActivityPub.ActivityPubController
   import Ecto.Query
 
-  def feed_redirect(conn, %{"nickname" => nickname}) do
+  def feed_redirect(conn, %{"nickname" => nickname} = params) do
     user = User.get_cached_by_nickname(nickname)
 
     case get_format(conn) do
       "html" -> Fallback.RedirectController.redirector(conn, nil)
+      "activity+json" -> ActivityPubController.user(conn, params)
       _ -> redirect conn, external: OStatus.feed_path(user)
     end
   end
diff --git a/lib/pleroma/web/router.ex b/lib/pleroma/web/router.ex
index 6806e8a75..4803a6370 100644
--- a/lib/pleroma/web/router.ex
+++ b/lib/pleroma/web/router.ex
@@ -199,7 +199,7 @@ def user_fetcher(username) do
   end
 
   pipeline :ostatus do
-    plug :accepts, ["xml", "atom", "html"]
+    plug :accepts, ["xml", "atom", "html", "activity+json"]
   end
 
   scope "/", Pleroma.Web do
@@ -217,6 +217,14 @@ def user_fetcher(username) do
     post "/push/subscriptions/:id", Websub.WebsubController, :websub_incoming
   end
 
+  pipeline :activitypub do
+    plug :accepts, ["activity+json"]
+  end
+
+  scope "/", Pleroma.Web.ActivityPub do
+    post "/users/:nickname/inbox", ActivityPubController, :inbox
+  end
+
   scope "/.well-known", Pleroma.Web do
     pipe_through :well_known