Add Thrift Client config and use it to disable stream 16KB limit

Summary:
- Create a new class `ThriftClientConfig` to set custom RPC configurations for Thrift Hack Clients that are not part of RPC Options.
- Use this new config to override Streaming buffer policy as described in D81055765
- Use the override in StreamingTestScript

Reviewed By: tlj77

Differential Revision: D83917740

fbshipit-source-id: ad8894f57ae1c5d55295a3f24ecc330d9e11d530

Author: Rashmi Makheja

third-party/thrift/src/thrift/lib/hack/src/ThriftClientBase.php

@@ -33,6 +33,7 @@ abstract class ThriftClientBase implements IThriftClient {
   protected TClientAsyncHandler $asyncHandler_;
   protected TClientEventHandler $eventHandler_;
   protected ?RpcOptions $options_;
+  protected ?ThriftClientConfig $config_;
 
   protected int $seqid_ = 0;
   abstract const string THRIFT_SVC_NAME;
@@ -122,6 +123,13 @@ public function onceWithOptions(RpcOptions $rpc_options)[write_props]: this {
     return $this;
   }
 
+  public function setThriftClientConfig(
+    ThriftClientConfig $config,
+  )[write_props]: this {
+    $this->config_ = $config;
+    return $this;
+  }
+
   protected function getAndResetOptions()[write_props]: ?RpcOptions {
     $options = $this->options_;
     $this->options_ = null;
@@ -395,6 +403,10 @@ class<TStreamResponseType> $stream_response_type,
     $out_transport->resetBuffer();
     list($result_msg, $_read_headers, $stream) =
       await $channel->genSendRequestStreamResponse($rpc_options, $msg);
+    $disable16kblimit = $this->config_?->getStreamDisable16KBLimit() ?? false;
+    if ($disable16kblimit) {
+      $stream->disable16KBBufferingPolicy();
+    }
 
     $stream_gen = $stream->gen<TStreamType>(
       ThriftStreamingSerializationHelpers::decodeStreamHelper(

third-party/thrift/src/thrift/lib/hack/src/ThriftClientConfig.php

@@ -0,0 +1,42 @@
+<?hh
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// @oss-enable: use namespace FlibSL\{C, Math, Str, Vec};
+
+// Use this to control hack language specific configs for Thrift Client
+final class ThriftClientConfig {
+  /**
+   * For streaming, default behavior is to send more credits when client has
+   * consumed either chunkBufferSize/2 payloads or 16KB bytes.
+   *
+   * When all payloads are close to 16KB, this means credit is sent after
+   * every payload. In such cases, clients can choose to disable 16KB limit
+   * and only send credits after chunkBufferSize/2 payloads are consumed.
+   */
+  private bool $streamDisable16KBLimit = false;
+  public function __construct()[] {}
+
+  public function setStreamDisable16KBLimit(bool $val)[write_props]: this {
+    $this->streamDisable16KBLimit = $val;
+    return $this;
+  }
+
+  public function getStreamDisable16KBLimit()[]: bool {
+    return $this->streamDisable16KBLimit;
+  }
+}