example/plugins/cpp-api/post_buffer/PostBuffer.cc

/**
  Licensed to the Apache Software Foundation (ASF) under one
  or more contributor license agreements.  See the NOTICE file
  distributed with this work for additional information
  regarding copyright ownership.  The ASF licenses this file
  to you 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.
 */

#include <iostream>
#include <string_view>
#include "tscpp/api/GlobalPlugin.h"
#include "tscpp/api/TransactionPlugin.h"
#include "tscpp/api/TransformationPlugin.h"
#include "tscpp/api/PluginInit.h"

using namespace atscppapi;
using std::cerr;
using std::endl;
using std::string;

namespace
{
GlobalPlugin *plugin;
}

class PostBufferTransformationPlugin : public TransformationPlugin
{
public:
  explicit PostBufferTransformationPlugin(Transaction &transaction)
    : TransformationPlugin(transaction, REQUEST_TRANSFORMATION), transaction_(transaction)
  {
    buffer_.reserve(1024); // not required, this is an optimization to start the buffer at a slightly higher value.
    (void)transaction_;
  }

  void
  consume(std::string_view data) override
  {
    buffer_.append(data.data(), data.length());
  }

  void
  handleInputComplete() override
  {
    produce(buffer_);
    setOutputComplete();
  }

  ~PostBufferTransformationPlugin() override {}

private:
  Transaction &transaction_;
  string buffer_;
};

class GlobalHookPlugin : public GlobalPlugin
{
public:
  GlobalHookPlugin() { registerHook(HOOK_READ_REQUEST_HEADERS_POST_REMAP); }
  void
  handleReadRequestHeadersPostRemap(Transaction &transaction) override
  {
    cerr << "Read Request Headers Post Remap" << endl;
    cerr << "Path: " << transaction.getClientRequest().getUrl().getPath() << endl;
    cerr << "Method: " << HTTP_METHOD_STRINGS[transaction.getClientRequest().getMethod()] << endl;
    if (transaction.getClientRequest().getMethod() == HTTP_METHOD_POST) {
      transaction.addPlugin(new PostBufferTransformationPlugin(transaction));
    }

    transaction.resume();
  }
};

void
TSPluginInit(int argc ATSCPPAPI_UNUSED, const char *argv[] ATSCPPAPI_UNUSED)
{
  if (!RegisterGlobalPlugin("CPP_Example_PostBuffer", "apache", "dev@trafficserver.apache.org")) {
    return;
  }
  plugin = new GlobalHookPlugin();
}