From 656ed7c84a5d8e423999457f66d8259ec8aa9a44 Mon Sep 17 00:00:00 2001
From: Ivan Tashkinov <ivantashkinov@gmail.com>
Date: Fri, 25 Jan 2019 15:10:21 +0300
Subject: [PATCH] [#534] Configurable outgoing federation reachability timeout.

---
 config/config.exs                 |  1 +
 docs/config.md                    |  1 +
 lib/pleroma/instances.ex          | 16 ++++++++++++++--
 lib/pleroma/instances/instance.ex |  6 ++++--
 4 files changed, 20 insertions(+), 4 deletions(-)

diff --git a/config/config.exs b/config/config.exs
index d30b0aad0..7a1a875c9 100644
--- a/config/config.exs
+++ b/config/config.exs
@@ -125,6 +125,7 @@ config :pleroma, :instance,
   banner_upload_limit: 4_000_000,
   registrations_open: true,
   federating: true,
+  federation_reachability_timeout_days: 90,
   allow_relay: true,
   rewrite_policy: Pleroma.Web.ActivityPub.MRF.NoOpPolicy,
   public: true,
diff --git a/docs/config.md b/docs/config.md
index 6bf7b9ea7..3f4588299 100644
--- a/docs/config.md
+++ b/docs/config.md
@@ -72,6 +72,7 @@ config :pleroma, Pleroma.Mailer,
 * `invites_enabled`: Enable user invitations for admins (depends on `registrations_open: false`).
 * `account_activation_required`: Require users to confirm their emails before signing in.
 * `federating`: Enable federation with other instances
+* `federation_reachability_timeout_days`: Timeout (in days) of each external federation target being unreachable prior to pausing federating to it.
 * `allow_relay`: Enable Pleroma’s Relay, which makes it possible to follow a whole instance
 * `rewrite_policy`: Message Rewrite Policy, either one or a list. Here are the ones available by default:
   * `Pleroma.Web.ActivityPub.MRF.NoOpPolicy`: Doesn’t modify activities (default)
diff --git a/lib/pleroma/instances.ex b/lib/pleroma/instances.ex
index 6d445d6b3..0b08f0eb8 100644
--- a/lib/pleroma/instances.ex
+++ b/lib/pleroma/instances.ex
@@ -8,8 +8,20 @@ defmodule Pleroma.Instances do
   defdelegate set_reachable(url), to: @adapter
   defdelegate set_unreachable(url, unreachable_since \\ nil), to: @adapter
 
-  def reachability_time_threshold,
-    do: NaiveDateTime.add(NaiveDateTime.utc_now(), -30 * 24 * 3600, :second)
+  def reachability_datetime_threshold do
+    federation_reachability_timeout_days =
+      Pleroma.Config.get(:instance)[:federation_reachability_timeout_days] || 90
+
+    if federation_reachability_timeout_days > 0 do
+      NaiveDateTime.add(
+        NaiveDateTime.utc_now(),
+        -federation_reachability_timeout_days * 24 * 3600,
+        :second
+      )
+    else
+      ~N[0000-01-01 00:00:00]
+    end
+  end
 
   def host(url_or_host) when is_binary(url_or_host) do
     if url_or_host =~ ~r/^http/i do
diff --git a/lib/pleroma/instances/instance.ex b/lib/pleroma/instances/instance.ex
index a17c8dab1..60e8d0e21 100644
--- a/lib/pleroma/instances/instance.ex
+++ b/lib/pleroma/instances/instance.ex
@@ -39,7 +39,8 @@ defmodule Pleroma.Instances.Instance do
       Repo.all(
         from(i in Instance,
           where:
-            i.host in ^hosts and i.unreachable_since <= ^Instances.reachability_time_threshold(),
+            i.host in ^hosts and
+              i.unreachable_since <= ^Instances.reachability_datetime_threshold(),
           select: i.host
         )
       )
@@ -51,7 +52,8 @@ defmodule Pleroma.Instances.Instance do
     !Repo.one(
       from(i in Instance,
         where:
-          i.host == ^host(url) and i.unreachable_since <= ^Instances.reachability_time_threshold(),
+          i.host == ^host(url) and
+            i.unreachable_since <= ^Instances.reachability_datetime_threshold(),
         select: true
       )
     )