capture rogue :gun_error message from remote server shutdown

CHANGELOG.md

@@ -6,6 +6,15 @@ The format is based on [Keep a
 Changelog](https://keepachangelog.com/en/1.0.0/), and this project adheres to
 [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## 0.3.2 - 2021-02-03
+
+### Fixed
+
+- Fixed edge case where the remote server shutting down would not emit a
+  `ChannelClosed` event
+    - this and heartbeats caused the odd `:gun_error` atom from
+      [#12](https://github.com/NFIBrokerage/slipstream/issues/12)
+
 ## 0.3.1 - 2021-02-03
 
 ### Fixed

lib/slipstream/connection/pipeline.ex

@@ -84,18 +84,12 @@ defmodule Slipstream.Connection.Pipeline do
 
   defp decode_message(
          %{
-           raw_message: {:gun_down, conn, _protocol, _reason, affected_refs, _},
-           state: %{conn: conn, stream_ref: stream_ref}
+           raw_message:
+             {:gun_down, conn, _protocol, _reason, _affected_refs, _},
+           state: %{conn: conn}
          } = p
        ) do
-    if stream_ref in affected_refs do
-      put_message(p, event(%Events.ChannelClosed{reason: :closed_by_remote}))
-    else
-      # coveralls-ignore-start
-      put_message(p, event(%Events.NoOp{}))
-
-      # coveralls-ignore-stop
-    end
+    put_message(p, event(%Events.ChannelClosed{reason: :closed_by_remote}))
   end
 
   defp decode_message(