3 files changed, 14 insertions, 4 deletions
diff --git a/actioncable/lib/action_cable/storage_adapter.rb b/actioncable/lib/action_cable/storage_adapter.rb
index f1c395eb3a..a4fe12c770 100644
--- a/actioncable/lib/action_cable/storage_adapter.rb
+++ b/actioncable/lib/action_cable/storage_adapter.rb
@@ -1,7 +1,7 @@
 module ActionCable
   module StorageAdapter
     autoload :Base, 'action_cable/storage_adapter/base'
-    autoload :Postgres, 'action_cable/storage_adapter/postgres'
+    autoload :PostgreSQL, 'action_cable/storage_adapter/postgresql'
     autoload :Redis, 'action_cable/storage_adapter/redis'
   end
 end
diff --git a/actioncable/lib/action_cable/storage_adapter/postgres.rb b/actioncable/lib/action_cable/storage_adapter/postgresql.rb
index 5d874533be..1d8460e2ea 100644
--- a/actioncable/lib/action_cable/storage_adapter/postgres.rb
+++ b/actioncable/lib/action_cable/storage_adapter/postgresql.rb
@@ -1,8 +1,14 @@
 require 'thread'
 
+begin
+  require 'pg'
+rescue Gem::LoadError => e
+  raise Gem::LoadError, "You are trying to use the PostgreSQL ActionCable adapter, but do not have the proper gems installed. Add `gem 'pg'` to your Gemfile (and ensure its version is at the minimum required by ActionCable)."
+end
+
 module ActionCable
   module StorageAdapter
-    class Postgres < Base
+    class PostgreSQL < Base
       # The storage instance used for broadcasting. Not intended for direct user use.
       def broadcast(channel, payload)
         with_connection do |pg_conn|
diff --git a/actioncable/lib/action_cable/storage_adapter/redis.rb b/actioncable/lib/action_cable/storage_adapter/redis.rb
index 3e0ede057a..62a3971ec7 100644
--- a/actioncable/lib/action_cable/storage_adapter/redis.rb
+++ b/actioncable/lib/action_cable/storage_adapter/redis.rb
@@ -1,5 +1,9 @@
-require 'em-hiredis'
-require 'redis'
+begin
+  require 'em-hiredis'
+  require 'redis'
+rescue Gem::LoadError => e
+  raise Gem::LoadError, "You are trying to use the Redis ActionCable adapter, but do not have the proper gems installed. Add `gem 'em-hiredis'` and `gem 'redis'` to your Gemfile (and ensure its version is at the minimum required by ActionCable)."
+end
 
 module ActionCable
   module StorageAdapter