TestErrorHandlingPar.cpp

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/**
 * @file TestErrorHandlingPar.cpp
 * @brief Example demonstrating parallel error handling in MOAB
 *
 * This example shows how to:
 * - Initialize and finalize MOAB's error handler in parallel
 * - Test different types of errors in parallel execution
 * - Handle global fatal errors vs per-processor errors
 * - Use parallel file loading with different partition methods
 *
 * The example demonstrates two test cases:
 * - Test case 1: Tests a global fatal error (MB_NOT_IMPLEMENTED)
 * - Test case 2: Tests a per-processor error (MB_FAILURE)
 *
 * @author MOAB Development Team
 * @date 2024
 *
 
 * Description: This example tests MOAB's trace back error handler in parallel.\n
 *
 * <b>To run</b>: mpiexec -np \c n ./TestErrorHandlingPar <test_case_num(1 to 2)> \n
 *
 * @param argc Number of command line arguments
 * @param argv Command line arguments array
 * @return 0 on success, 1 on failure
 */
 
#include "moab/Core.hpp"
#ifdef MOAB_HAVE_MPI
#include "moab_mpi.h"
#endif
 
#include <iostream>
#include <memory>
 
using namespace moab;
using namespace std;
 
// In this test case, a global fatal error MB_NOT_IMPLEMENTED is returned by MOAB
// Note, it is printed by root processor 0 only
ErrorCode TestErrorHandlingPar_1()
{
    Core moab;
    Interface& mb = moab;
 
    string opts = ";;";
#ifdef MOAB_HAVE_MPI
    // Use parallel options
    opts += "PARALLEL=READ_PART;PARTITION_METHOD=SQIJ";
#endif
 
    // Load a CAM-FV file and read a variable on edges (not supported yet)
    string test_file = string( MESH_DIR ) + string( "/io/fv3x46x72.t.3.nc" );
    opts += ";VARIABLE=US";
    MB_CHK_ERR( mb.load_file( test_file.c_str(), NULL, opts.c_str() ) );
 
    return MB_SUCCESS;
}
 
// In this test case, a per-processor relevant error MB_FAILURE is returned by MOAB
// Note, it is printed by all processors
ErrorCode TestErrorHandlingPar_2()
{
    Core moab;
    Interface& mb = moab;
 
    string opts = ";;";
#ifdef MOAB_HAVE_MPI
    // Use parallel options
    opts += "PARALLEL=READ_PART;PARTITION_METHOD=UNKNOWN";
#endif
 
    // Load a CAM-FV file with an unknown partition method specified
    string test_file = string( MESH_DIR ) + string( "/io/fv3x46x72.t.3.nc" );
    opts += ";VARIABLE=T";
    MB_CHK_ERR( mb.load_file( test_file.c_str(), NULL, opts.c_str() ) );
 
    return MB_SUCCESS;
}
 
int main( int argc, char** argv )
{
    if( argc < 2 )
    {
        cout << "Usage: " << argv[0] << " <test_case_num(1 to 2>" << endl;
        return 0;
    }
 
#ifdef MOAB_HAVE_MPI
    MPI_Init( &argc, &argv );
#endif
 
    // Initialize error handler, optional for this example (using moab instances)
    MBErrorHandler_Init();
 
    ErrorCode rval = MB_SUCCESS;
 
    int test_case_num = atoi( argv[1] );
    switch( test_case_num )
    {
        case 1:
            MB_CHK_ERR( TestErrorHandlingPar_1() );
            break;
        case 2:
            MB_CHK_ERR( TestErrorHandlingPar_2() );
            break;
        default:
            break;
    }
 
    // Finalize error handler, optional for this example (using moab instances)
    MBErrorHandler_Finalize();
 
#ifdef MOAB_HAVE_MPI
    MPI_Finalize();
#endif
 
    return 0;
}