From a4139f28162f60c5a207b4fc7d3182aac2bb981b Mon Sep 17 00:00:00 2001
From: =?utf8?q?Christopher=20Cot=C3=A9?= <chris@entropealabs.com>
Date: Fri, 3 Dec 2021 15:08:10 -0500
Subject: [PATCH] handle failed lookups

---
 lib/router/realms/session.ex | 31 ++++++++++++++++++-------------
 lib/router/session.ex        | 25 +++++++++++++++----------
 2 files changed, 33 insertions(+), 23 deletions(-)

diff --git a/lib/router/realms/session.ex b/lib/router/realms/session.ex
index 7f838d6..ce7402d 100644
--- a/lib/router/realms/session.ex
+++ b/lib/router/realms/session.ex
@@ -54,19 +54,24 @@ defmodule Wampex.Router.Realms.Session do
   end
 
   def unsubscribe(db, realm, {id, _from} = value, subscriptions) do
-    {_id, topic, wc} = sub = get_subscription(id, subscriptions)
-
-    key =
-      case wc do
-        true ->
-          get_wildcard_key(topic)
-
-        false ->
-          topic
-      end
-
-    ClusterKV.update(db, realm, key, value, :remove)
-    remove_val(sub, subscriptions)
+    case get_subscription(id, subscriptions) do
+      {_id, topic, wc} = sub ->
+        key =
+          case wc do
+            true ->
+              get_wildcard_key(topic)
+
+            false ->
+              topic
+          end
+
+        ClusterKV.update(db, realm, key, value, :remove)
+        remove_val(sub, subscriptions)
+
+      _ ->
+        Logger.error("Unable to unsubscribe #{id} not present in subscriptions: #{subscriptions}")
+        subscriptions
+    end
   end
 
   def subscriptions(db, realm, topic) do
diff --git a/lib/router/session.ex b/lib/router/session.ex
index 4c7cceb..66de4b5 100644
--- a/lib/router/session.ex
+++ b/lib/router/session.ex
@@ -515,16 +515,22 @@ defmodule Wampex.Router.Session do
           }
         } = data
       ) do
-    {call_id, _, {pid, node}} =
-      Enum.find(inv, fn
-        {_, %Invocation{request_id: ^id}, _} -> true
-        _ -> false
-      end)
+    case Enum.find(inv, fn
+           {_, %Invocation{request_id: ^id}, _} -> true
+           _ -> false
+         end) do
+      {call_id, _, {pid, node}} ->
+        send(
+          {proxy, node},
+          {%Result{request_id: call_id, arg_list: arg_l, arg_kw: arg_kw, details: opts}, pid}
+        )
 
-    send(
-      {proxy, node},
-      {%Result{request_id: call_id, arg_list: arg_l, arg_kw: arg_kw, details: opts}, pid}
-    )
+        Logger.info("Yield: #{realm} - #{id}")
+
+      _ ->
+        Logger.error("Unable to yield: #{id} not present in invocations: #{inspect(inv)}")
+        :ok
+    end
 
     inv =
       Enum.filter(inv, fn
@@ -532,7 +538,6 @@ defmodule Wampex.Router.Session do
         _ -> true
       end)
 
-    Logger.info("Yield: #{realm} - #{id}")
     {:ok, %SL{data | data: %Sess{data.data | invocations: inv, yield: nil}}, [{:next_event, :internal, :transition}]}
   end
 
-- 
2.45.3