Merge pull request #193 from redis-rb/workaround-ssl-socket-buffer-clear

Workaround SSLSocket always clearing the buffer

Author: casperisfine

lib/redis_client/ruby_connection/buffered_io.rb

@@ -190,7 +190,8 @@ def ensure_remaining(bytes)
 
       def fill_buffer(strict, size = @chunk_size)
         remaining = size
-        start = @offset - @buffer.bytesize
+        buffer_size = @buffer.bytesize
+        start = @offset - buffer_size
         empty_buffer = start >= 0
 
         loop do
@@ -199,12 +200,27 @@ def fill_buffer(strict, size = @chunk_size)
           else
             @io.read_nonblock([remaining, @chunk_size].max, exception: false)
           end
+
           case bytes
           when :wait_readable
+            # Ref: https://github.com/redis-rb/redis-client/issues/190
+            # SSLSocket always clear the provided buffer, even when it didn't
+            # read anything. So we need to reset the offset accordingly.
+            if empty_buffer && @buffer.empty?
+              @offset -= buffer_size
+            end
+
             unless @io.to_io.wait_readable(@read_timeout)
               raise ReadTimeoutError, "Waited #{@read_timeout} seconds" unless @blocking_reads
             end
           when :wait_writable
+            # Ref: https://github.com/redis-rb/redis-client/issues/190
+            # SSLSocket always clear the provided buffer, even when it didn't
+            # read anything. So we need to reset the offset accordingly.
+            if empty_buffer && @buffer.empty?
+              @offset -= buffer_size
+            end
+
             @io.to_io.wait_writable(@write_timeout) or raise(WriteTimeoutError, "Waited #{@write_timeout} seconds")
           when nil
             raise EOFError

test/redis_client/middlewares_test.rb

@@ -70,11 +70,11 @@ def test_multi_instrumentation
     end
 
     module DummyMiddleware
-      def call(command, _config)
+      def call(command, _config, &_)
         command
       end
 
-      def call_pipelined(commands, _config)
+      def call_pipelined(commands, _config, &_)
         commands
       end
     end

test/redis_client_test.rb

@@ -52,7 +52,7 @@ def test_dns_resolution_failure
 
   def test_older_server
     fake_redis5_driver = Class.new(RedisClient::RubyConnection) do
-      def call_pipelined(commands, *)
+      def call_pipelined(commands, *, &_)
         if commands.any? { |c| c == ["HELLO", "3"] }
           raise RedisClient::CommandError, "ERR unknown command `HELLO`, with args beginning with: `3`"
         else
@@ -71,7 +71,7 @@ def call_pipelined(commands, *)
 
   def test_redis_6_server_with_missing_hello_command
     fake_redis6_driver = Class.new(RedisClient::RubyConnection) do
-      def call_pipelined(commands, *)
+      def call_pipelined(commands, *, &_)
         if commands.any? { |c| c == ["HELLO", "3"] }
           raise RedisClient::CommandError, "ERR unknown command 'HELLO'"
         else