// Last Update:2016-12-09 17:41:07

#include <rados/librados.hpp>
#include <string>
#include <list>

int main(int argc, const char *argv[])
{
  int ret = 0 ;
  // Get cluster handle and connect to cluster
  std::cout<<"ceph Cluster connect begin."<<std::endl;
  std::string cluster_name("ceph");
  std::string user_name("client.admin");
  librados::Rados cluster ;

  ret = cluster.init2(user_name.c_str(), cluster_name.c_str(), 0);
  if (ret < 0)
  {
    std::cerr << "Couldn't initialize the cluster handle! error " << ret << std::endl;
    ret = EXIT_FAILURE;
    return 1;
  } else {
    std::cout << "Created a cluster handle." << std::endl;
  }

  ret = cluster.conf_read_file("/etc/ceph/ceph.conf");
  if (ret < 0)
  {
    std::cerr << "Couldn't read the Ceph configuration file! error " << ret << std::endl;
    ret = EXIT_FAILURE;
    return 1;
  } else {
    std::cout << "Read the Ceph configuration file Succeed." << std::endl;
  }

  ret = cluster.connect();
  if (ret < 0) {
    std::cerr << "Couldn't connect to cluster! error " << ret << std::endl;
    ret = EXIT_FAILURE;
    return 1;
  }else{
    std::cout << "Connected to the cluster." << std::endl;
  }

  std::cout<<"ceph Cluster connect end."<<std::endl;
  // IO context poolname pool-1
  std::cout<<"ceph Cluster create io context for pool begin."<<std::endl;
  librados::IoCtx io_ctx ;
  std::string pool_name("pool-1");

  ret = cluster.ioctx_create(pool_name.c_str(), io_ctx);
  if (ret < 0)
  {
    std::cerr << "Couldn't set up ioctx! error " << ret << std::endl;
    exit(EXIT_FAILURE);
  } else {
    std::cout << "Created an ioctx for the pool." << std::endl;
  }
  std::cout<<"ceph Cluster create io context for pool end."<<std::endl;
  // Write an object synchronously
  std::cout<<"Write an object synchronously begin."<<std::endl;

  librados::bufferlist bl;
  std::string objectId("hw");
  std::string objectContent("Hello World!");
  bl.append(objectContent);

  ret = io_ctx.write_full("hw", bl);
  if (ret < 0) {
    std::cerr << "Couldn't write object! error " << ret << std::endl;
    exit(EXIT_FAILURE);
  } else {
    std::cout << "Wrote new object 'hw' " << std::endl;
  }

  std::cout<<"Write an object synchronously end."<<std::endl;
  // Add an xattr to the object.
  librados::bufferlist lang_bl;
  lang_bl.append("en_US");
  io_ctx.setxattr(objectId, "lang", lang_bl);
  // Read the object back asynchronously
  librados::bufferlist read_buf;
  int read_len = 4194304;

  //Create I/O Completion.
  librados::AioCompletion *read_completion = librados::Rados::aio_create_completion();
  //Send read request.
  io_ctx.aio_read(objectId, read_completion, &read_buf, read_len, 0 );
  // Wait for the request to complete, and print content
  read_completion->wait_for_complete();
  read_completion->get_return_value();
  std::cout<< "Object name: " << objectId << "\n"
    << "Content: " << read_buf.c_str() << std::endl ;
  // Read the xattr.
  librados::bufferlist lang_res;
  io_ctx.getxattr(objectId, "lang", lang_res);
  std::cout<< "Object xattr: " << lang_res.c_str() << std::endl ;
  // Print the list of pools
  std::list<std::string> pools ;
  cluster.pool_list(pools );
  std::cout << "List of pools from this cluster handle" << std::endl ;
  for (std::list<std::string>::iterator i = pools.begin(); i != pools.end(); ++i)
    std::cout << *i << std::endl;
  // Print the list of objects
  librados::ObjectIterator oit=io_ctx.objects_begin();
  librados::ObjectIterator oet=io_ctx.objects_end();
  std::cout<< "List of objects from this pool" << std::endl ;
  for(; oit!= oet; oit++ ) {
    std::cout << "\t" << oit->first << std::endl ;
  }
  // Remove the xattr
  io_ctx.rmxattr(objectId, "lang");
  // Remove the object.
  io_ctx.remove(objectId);
  // Cleanup
  io_ctx.close();
  cluster.shutdown();
  return 0 ;
}