+
+ def publish(topic, user, activity) do
+ query = from sub in WebsubServerSubscription,
+ where: sub.topic == ^topic and sub.state == "active"
+ subscriptions = Repo.all(query)
+ Enum.each(subscriptions, fn(sub) ->
+ response = user
+ |> FeedRepresenter.to_simple_form([activity], [user])
+ |> :xmerl.export_simple(:xmerl_xml)
+ |> to_string
+
+ signature = sign(sub.secret || "", response)
+ Logger.debug("Pushing to #{sub.callback}")
+
+ HTTPoison.post(sub.callback, response, [
+ {"Content-Type", "application/atom+xml"},
+ {"X-Hub-Signature", "sha1=#{signature}"}
+ ])
+ end)
+ end
+
+ def sign(secret, doc) do
+ :crypto.hmac(:sha, secret, to_string(doc)) |> Base.encode16 |> String.downcase
+ end
+
+ def incoming_subscription_request(user, %{"hub.mode" => "subscribe"} = params) do
+ with {:ok, topic} <- valid_topic(params, user),
+ {:ok, lease_time} <- lease_time(params),
+ secret <- params["hub.secret"],
+ callback <- params["hub.callback"]
+ do
+ subscription = get_subscription(topic, callback)
+ data = %{
+ state: subscription.state || "requested",
+ topic: topic,
+ secret: secret,
+ callback: callback
+ }
+
+ change = Changeset.change(subscription, data)
+ websub = Repo.insert_or_update!(change)
+
+ change = Changeset.change(websub, %{valid_until:
+ NaiveDateTime.add(websub.updated_at, lease_time)})
+ websub = Repo.update!(change)
+
+ Pleroma.Web.Federator.enqueue(:verify_websub, websub)
+
+ {:ok, websub}
+ else {:error, reason} ->
+ Logger.debug("Couldn't create subscription.")
+ Logger.debug(inspect(reason))
+
+ {:error, reason}
+ end
+ end
+
+ defp get_subscription(topic, callback) do
+ Repo.get_by(WebsubServerSubscription, topic: topic, callback: callback) ||
+ %WebsubServerSubscription{}
+ end
+
+ # Temp hack for mastodon.
+ defp lease_time(%{"hub.lease_seconds" => ""}) do
+ {:ok, 60 * 60 * 24 * 3} # three days
+ end
+
+ defp lease_time(%{"hub.lease_seconds" => lease_seconds}) do
+ {:ok, String.to_integer(lease_seconds)}
+ end
+
+ defp lease_time(_) do
+ {:ok, 60 * 60 * 24 * 3} # three days
+ end
+
+ defp valid_topic(%{"hub.topic" => topic}, user) do
+ if topic == OStatus.feed_path(user) do
+ {:ok, OStatus.feed_path(user)}
+ else
+ {:error, "Wrong topic requested, expected #{OStatus.feed_path(user)}, got #{topic}"}
+ end
+ end
+
+ def subscribe(subscriber, subscribed, requester \\ &request_subscription/1) do
+ topic = subscribed.info["topic"]
+ # FIXME: Race condition, use transactions
+ {:ok, subscription} = with subscription when not is_nil(subscription) <- Repo.get_by(WebsubClientSubscription, topic: topic) do
+ subscribers = [subscriber.ap_id, subscription.subscribers] |> Enum.uniq
+ change = Ecto.Changeset.change(subscription, %{subscribers: subscribers})
+ Repo.update(change)
+ else _e ->
+ subscription = %WebsubClientSubscription{
+ topic: topic,
+ hub: subscribed.info["hub"],
+ subscribers: [subscriber.ap_id],
+ state: "requested",
+ secret: :crypto.strong_rand_bytes(8) |> Base.url_encode64,
+ user: subscribed
+ }
+ Repo.insert(subscription)
+ end
+ requester.(subscription)
+ end
+
+ def gather_feed_data(topic, getter \\ &HTTPoison.get/1) do
+ with {:ok, response} <- getter.(topic),
+ status_code when status_code in 200..299 <- response.status_code,
+ body <- response.body,
+ doc <- XML.parse_document(body),
+ uri when not is_nil(uri) <- XML.string_from_xpath("/feed/author[1]/uri", doc),
+ hub when not is_nil(hub) <- XML.string_from_xpath(~S{/feed/link[@rel="hub"]/@href}, doc) do
+
+ name = XML.string_from_xpath("/feed/author[1]/name", doc)
+ preferredUsername = XML.string_from_xpath("/feed/author[1]/poco:preferredUsername", doc)
+ displayName = XML.string_from_xpath("/feed/author[1]/poco:displayName", doc)
+ avatar = OStatus.make_avatar_object(doc)
+
+ {:ok, %{
+ "uri" => uri,
+ "hub" => hub,
+ "nickname" => preferredUsername || name,
+ "name" => displayName || name,
+ "host" => URI.parse(uri).host,
+ "avatar" => avatar
+ }}
+ else e ->
+ {:error, e}
+ end
+ end
+
+ def request_subscription(websub, poster \\ &HTTPoison.post/3, timeout \\ 10_000) do
+ data = [
+ "hub.mode": "subscribe",
+ "hub.topic": websub.topic,
+ "hub.secret": websub.secret,
+ "hub.callback": Helpers.websub_url(Endpoint, :websub_subscription_confirmation, websub.id)
+ ]
+
+ # This checks once a second if we are confirmed yet
+ websub_checker = fn ->
+ helper = fn (helper) ->
+ :timer.sleep(1000)
+ websub = Repo.get_by(WebsubClientSubscription, id: websub.id, state: "accepted")
+ if websub, do: websub, else: helper.(helper)
+ end
+ helper.(helper)
+ end
+
+ task = Task.async(websub_checker)
+
+ with {:ok, %{status_code: 202}} <- poster.(websub.hub, {:form, data}, ["Content-type": "application/x-www-form-urlencoded"]),
+ {:ok, websub} <- Task.yield(task, timeout) do
+ {:ok, websub}
+ else e ->
+ Task.shutdown(task)
+
+ change = Ecto.Changeset.change(websub, %{state: "rejected"})
+ {:ok, websub} = Repo.update(change)
+
+ Logger.debug("Couldn't confirm subscription: #{inspect(websub)}")
+ Logger.debug("error: #{inspect(e)}")
+
+ {:error, websub}
+ end
+ end