Automatic Fork Safety

lib/excon/connection.rb

@@ -62,6 +62,7 @@ def logger=(logger)
     # @option params [Class] :instrumentor Responds to #instrument as in ActiveSupport::Notifications
     # @option params [String] :instrumentor_name Name prefix for #instrument events.  Defaults to 'excon'
     def initialize(params = {})
+      @pid = Process.pid
       @data = Excon.defaults.dup
       # merge does not deep-dup, so make sure headers is not the original
       @data[:headers] = @data[:headers].dup
@@ -480,6 +481,11 @@ def sockets
       @_excon_sockets ||= {}
       @_excon_sockets.compare_by_identity
 
+      if @pid != Process.pid
+        @_excon_sockets.clear # GC will take care of closing sockets
+        @pid = Process.pid
+      end
+
       if @data[:thread_safe_sockets]
         # In a multi-threaded world, if the same connection is used by multiple
         # threads at the same time to connect to the same destination, they may

tests/connection_tests.rb

@@ -36,6 +36,22 @@
         response = connection.request(path: '/bar', method: 'get')
         response.body == 'bar'
       end
+
+      if ::Process.respond_to?(:fork)
+        connection_id = connection.send(:socket).object_id
+        test("fork safety") do
+          read, write = IO.pipe
+          pid = fork do
+            connection_id = connection.send(:socket).object_id
+            write.write(Marshal.dump(connection_id))
+            write.close
+            exit!(0)
+          end
+          Process.waitpid(pid)
+          child_connection_id = Marshal.load(read)
+          child_connection_id != connection_id
+        end
+      end
     end
   end