Implement backup and restore

include/base/FoamInterface.h

@@ -2,9 +2,12 @@
 
 #include <mpi.h>
 
-#include <vector>
-#include <string>
+#include <filesystem>
 #include <memory>
+#include <string>
+#include <vector>
+
+namespace fs = std::filesystem;
 
 /*
  * In theory the class through which all calls to the OpenFOAM "environment" are made
@@ -78,6 +81,8 @@ class FoamInterface
   Foam::Time & getRuntime();
   Foam::argList & getArglist();
   Foam::fvMesh & getMesh();
+  fs::path currentTimePath() const;
+  void readTime(const std::string & path);
   void write();
 };
 }

include/base/FoamProblem.h

@@ -30,6 +30,16 @@ class FoamProblem : public ExternalProblem
   virtual FoamMesh const & mesh() const override { return *_foam_mesh; }
   virtual FoamMesh & mesh() override { return *_foam_mesh; }
 
+  /**
+   * Save the current state of the OpenFOAM solve.
+   */
+  void saveState();
+
+  /**
+   * Load the saved state of the OpenFOAM solve.
+   */
+  void loadState();
+
 protected:
   FoamMesh * _foam_mesh = nullptr;
   Hippo::FoamInterface * _interface = nullptr;

include/base/hippoApp.h

@@ -1,12 +1,3 @@
-//* This file is part of the MOOSE framework
-//* https://www.mooseframework.org
-//*
-//* All rights reserved, see COPYRIGHT for full restrictions
-//* https://github.com/idaholab/moose/blob/master/COPYRIGHT
-//*
-//* Licensed under LGPL 2.1, please see LICENSE for details
-//* https://www.gnu.org/licenses/lgpl-2.1.html
-
 #pragma once
 
 #include <MooseApp.h>
@@ -21,4 +12,7 @@ class hippoApp : public MooseApp
 
   static void registerApps();
   static void registerAll(Factory & f, ActionFactory & af, Syntax & s);
+
+  void preBackup() override;
+  void postRestore(const bool /* for_restart */) override;
 };

src/base/FoamInterface.C

@@ -134,6 +134,18 @@ FoamInterface::getArglist()
   return _impl->_args.args;
 }
 
+fs::path
+FoamInterface::currentTimePath() const
+{
+  return fs::path(_impl->_runtime.timePath());
+}
+
+void
+FoamInterface::readTime(const std::string & path)
+{
+  getRuntime().read();
+}
+
 void
 FoamInterface::write()
 {

src/base/FoamProblem.C

@@ -6,6 +6,7 @@
 #include <MooseError.h>
 #include <MooseTypes.h>
 #include <MooseVariableFieldBase.h>
+#include <filesystem>
 #include <libmesh/enum_order.h>
 #include <libmesh/fe_type.h>
 
@@ -101,6 +102,29 @@ FoamProblem::externalSolve()
 {
 }
 
+void
+FoamProblem::saveState()
+{
+  _interface->write();
+  _backup_foam_timestep_dir = _interface->currentTimePath().string();
+  printf("saveState() -> %s", _backup_foam_timestep_dir.c_str());
+}
+
+void
+FoamProblem::loadState()
+{
+  if (_backup_foam_timestep_dir.empty())
+  {
+    mooseError("Cannot load OpenFOAM state: the backup state path is not set.");
+  }
+  if (!fs::is_directory(_backup_foam_timestep_dir))
+  {
+    mooseError("Cannot load OpenFOAM state: the backup state path does not exist.");
+  }
+  printf("loadState() -> %s", _backup_foam_timestep_dir.c_str());
+  _interface->readTime(_backup_foam_timestep_dir);
+}
+
 InputParameters
 BuoyantFoamProblem::validParams()
 {

src/base/hippoApp.C

@@ -1,8 +1,12 @@
 #include "hippoApp.h"
-#include "Moose.h"
-#include "AppFactory.h"
-#include "ModulesApp.h"
-#include "MooseSyntax.h"
+#include "FoamProblem.h"
+
+#include <Moose.h>
+#include <AppFactory.h>
+#include <ModulesApp.h>
+#include <MooseSyntax.h>
+
+#include <cstdlib>
 
 InputParameters
 hippoApp::validParams()
@@ -38,6 +42,96 @@ hippoApp::registerApps()
   registerApp(hippoApp);
 }
 
+void
+hippoApp::preBackup()
+{
+  auto problem = reinterpret_cast<FoamProblem *>(&feProblem());
+  if (!problem)
+  {
+    mooseError("FoamProblem must be used with a Hippo App");
+  }
+  printf("preBackup()\n");
+  problem->saveState();
+
+  // auto problem = reinterpret_cast<FoamProblem *>(&feProblem());
+  // if (!problem)
+  // {
+  //   mooseError("FoamProblem must be used with a Hippo App");
+  // }
+  // auto * foam_interface = problem->mesh().getFoamInterface();
+  // foam_interface->write();
+
+  // // std::string temp_dir = std::getenv("TMP");
+  // // if (temp_dir.empty())
+  // // {
+  // //   temp_dir = "/tmp";
+  // // }
+
+  // auto backup_dir = fs::path("./backup");
+  // if (!fs::is_directory(backup_dir))
+  // {
+  //   fs::create_directory(backup_dir);
+  // }
+  // auto time_path = foam_interface->currentTimePath();
+  // auto backup_path = backup_dir / time_path.filename();
+  // printf("backup %s -> %s\n", time_path.c_str(), backup_path.c_str());
+  // fs::copy(
+  //     time_path, backup_path, fs::copy_options::overwrite_existing |
+  //     fs::copy_options::recursive);
+
+  // // auto tid = parameters().get<THREAD_ID>("_tid");
+  // // THREAD_ID tid = processor_id();
+  // // auto * app =
+  // //     reinterpret_cast<hippoApp
+  // //     *>(AppFactory::instance().registeredObjects().at("hippoApp").get());
+  // // std::vector<std::string> vol_scalar_fields;
+  // // for (const auto & obj_name : app->feProblem())
+
+  // //   _restartable_data[tid].addData(std::move(foam_data));
+  // // printf("tid=%u\n", tid);
+  // // printf("_restartable_data.size()=%lu\n", _restartable_data.size());
+
+  // //   // TODO: look at 'readCheckpoint' and 'writeCheckpoint' in precice adapter.
+  // //   // OR:
+  // //   // _interface->getMesh().writeObject(
+  // //   //     IOstream::streamFormat fmt, IOstream::versionNumber ver, IOstream::compressionType cmp, )
+  // // }
+}
+
+void
+hippoApp::postRestore(const bool for_restart)
+{
+  auto problem = reinterpret_cast<FoamProblem *>(&feProblem());
+  if (!problem)
+  {
+    mooseError("FoamProblem must be used with a Hippo App");
+  }
+  printf("postRestore()\n");
+  problem->loadState();
+
+  // auto problem = reinterpret_cast<FoamProblem *>(&feProblem());
+  // if (!problem)
+  // {
+  //   mooseError("FoamProblem must be used with a Hippo App");
+  // }
+  // auto * foam_interface = problem->mesh().getFoamInterface();
+
+  // auto time_path = foam_interface->currentTimePath();
+  // auto backup_dir = fs::path("./backup");
+  // auto backup_path = backup_dir / time_path.filename();
+  // if (!fs::is_directory(backup_path))
+  // {
+  //   return;
+  // }
+  // printf("restoring %s -> %s\n", backup_path.c_str(), time_path.c_str());
+  // fs::copy(
+  //     backup_path, time_path, fs::copy_options::overwrite_existing |
+  //     fs::copy_options::recursive);
+  // foam_interface->readTime("");
+  // // std::vector<double> _;
+  // // foam_interface->getWallHeatFlux(_, 0);
+}
+
 /***************************************************************************************************
  *********************** Dynamic Library Entry Points - DO NOT MODIFY ******************************
  **************************************************************************************************/

test/tests/restart/restart_from_transient_serial/.gitignore

@@ -0,0 +1,13 @@
+# Files generated by running the buoyantFoam tests
+**/processor*/*
+**/postProcessing/*
+**/constant/polyMesh/*
+**/buoyantCavity/[1-9]/*
+**/buoyantCavity/[1-9][0-9]/*
+*.blockMesh
+*.buoyantFoam
+*.createGraphs
+*.postProcess.*
+
+# Files for displaying OpenFOAM meshes in paraview
+**/buoyantCavity/*.foam

test/tests/restart/restart_from_transient_serial/buoyantCavity/0/T

@@ -0,0 +1,44 @@
+/*--------------------------------*- C++ -*----------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     | Website:  https://openfoam.org
+    \\  /    A nd           | Version:  10
+     \\/     M anipulation  |
+\*---------------------------------------------------------------------------*/
+FoamFile
+{
+    format      ascii;
+    class       volScalarField;
+    location    "0";
+    object      T;
+}
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+dimensions      [0 0 0 1 0 0 0];
+
+internalField   uniform 293;
+
+boundaryField
+{
+    topAndBottom
+    {
+        type            zeroGradient;
+    }
+    frontAndBack
+    {
+        type            zeroGradient;
+    }
+    hot
+    {
+        type            fixedValue;
+        value           uniform 307.75;
+    }
+    cold
+    {
+        type            fixedValue;
+        value           uniform 288.15;
+    }
+}
+
+
+// ************************************************************************* //

test/tests/restart/restart_from_transient_serial/buoyantCavity/0/U

@@ -0,0 +1,42 @@
+/*--------------------------------*- C++ -*----------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     | Website:  https://openfoam.org
+    \\  /    A nd           | Version:  10
+     \\/     M anipulation  |
+\*---------------------------------------------------------------------------*/
+FoamFile
+{
+    format      ascii;
+    class       volVectorField;
+    location    "0";
+    object      U;
+}
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+dimensions      [0 1 -1 0 0 0 0];
+
+internalField   uniform (0 0 0);
+
+boundaryField
+{
+    topAndBottom
+    {
+        type            noSlip;
+    }
+    frontAndBack
+    {
+        type            noSlip;
+    }
+    hot
+    {
+        type            noSlip;
+    }
+    cold
+    {
+        type            noSlip;
+    }
+}
+
+
+// ************************************************************************* //

test/tests/restart/restart_from_transient_serial/buoyantCavity/0/alphat

@@ -0,0 +1,50 @@
+/*--------------------------------*- C++ -*----------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     | Website:  https://openfoam.org
+    \\  /    A nd           | Version:  10
+     \\/     M anipulation  |
+\*---------------------------------------------------------------------------*/
+FoamFile
+{
+    format      ascii;
+    class       volScalarField;
+    location    "0";
+    object      alphat;
+}
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+dimensions      [1 -1 -1 0 0 0 0];
+
+internalField   uniform 0;
+
+boundaryField
+{
+    topAndBottom
+    {
+        type            compressible::alphatWallFunction;
+        Prt             0.85;
+        value           uniform 0;
+    }
+    frontAndBack
+    {
+        type            compressible::alphatWallFunction;
+        Prt             0.85;
+        value           uniform 0;
+    }
+    hot
+    {
+        type            compressible::alphatWallFunction;
+        Prt             0.85;
+        value           uniform 0;
+    }
+    cold
+    {
+        type            compressible::alphatWallFunction;
+        Prt             0.85;
+        value           uniform 0;
+    }
+}
+
+
+// ************************************************************************* //