From 511a116052fb06db355b62448185c701bc2d271f Mon Sep 17 00:00:00 2001
From: blttkgl <buluttekgul@gmail.com>
Date: Wed, 13 May 2026 14:35:39 +0300
Subject: [PATCH 1/2] Add multiregion function object reader support (#33)

---
 .../coolingCylinder2D/coolingCylinder2D.py    | 94 +++++++++++++++++++
 flowboost/openfoam/data/base.py               | 38 ++++++--
 tests/flowboost/openfoam/test_data_unit.py    | 39 ++++++++
 3 files changed, 162 insertions(+), 9 deletions(-)
 create mode 100644 examples/coolingCylinder2D/coolingCylinder2D.py

diff --git a/examples/coolingCylinder2D/coolingCylinder2D.py b/examples/coolingCylinder2D/coolingCylinder2D.py
new file mode 100644
index 0000000..e57fb3b
--- /dev/null
+++ b/examples/coolingCylinder2D/coolingCylinder2D.py
@@ -0,0 +1,94 @@
+from __future__ import annotations
+
+import warnings
+from pathlib import Path
+
+import coloredlogs
+import polars as pl
+
+from flowboost import (
+    Case,
+    Constraint,
+    Dictionary,
+    Dimension,
+    Manager,
+    Objective,
+    Session,
+)
+
+def averageT(case: Case):
+    """Calculate the lift to drag ratio from simulation results."""
+    dataframe = case.data.simple_function_object_reader("fluid/cylinderT")
+
+    if dataframe is None:
+        return None
+    return (
+        dataframe.select(pl.last("areaAverage(T)")).item()
+    )
+
+
+
+
+
+if __name__ == "__main__":
+    coloredlogs.install(level="INFO")
+
+    # --- Session ---
+    session = Session(
+        name="coolingCylinder2D",
+        data_dir=Path("flowboost_data"),
+        clone_method="copy",
+        max_evaluations=50,
+        bo_concurrency=3
+    )
+
+    # --- Template case ---
+    cooling_case = Case.from_tutorial(
+        "multiRegion/CHT/coolingCylinder2D",
+        Path(session.data_dir, "coolingCylinder2D_template"),
+        method="copy",
+    )
+    cooling_case.dictionary("system/controlDict").entry("writeInterval").set("20")
+
+    session.attach_template_case(case=cooling_case)
+
+    # --- Objectives ---
+
+    objective = Objective(
+        name="averageT",
+        minimize=False,
+        objective_function=averageT,
+    )
+
+
+
+    # --- Search space ---
+    DICT_FILE = "system/blockMeshDict"
+
+    radius_dim = Dimension.range(
+        name="cylinderRadius",
+        link=Dictionary.link(DICT_FILE).entry("cylinderRadius"),
+        lower=-0.001,
+        upper=0.01,
+    )
+
+
+
+    session.configure_optimization(
+        objectives=[objective],
+        search_space=[radius_dim]
+    )
+
+    # --- Job manager ---
+    session.job_manager = session.job_manager or Manager.create(
+        scheduler="Local",
+        wdir=session.data_dir,
+        job_limit=1,
+    )
+    session.job_manager.monitoring_interval = 10
+
+    # --- Run ---
+    session.backend.initialization_trials = 10
+    session.clean_pending_cases()
+    session.start()
+
diff --git a/flowboost/openfoam/data/base.py b/flowboost/openfoam/data/base.py
index 621e6e9..b74fe28 100644
--- a/flowboost/openfoam/data/base.py
+++ b/flowboost/openfoam/data/base.py
@@ -97,21 +97,39 @@ def discover_function_objects(self) -> dict[str, dict[str, list[Path]]]:
 
         function_objects = {}
         for function_dir in filter(Path.is_dir, self.post_processing_path.iterdir()):
-            time_dirs = self._time_dirs_for_function_object(function_dir)
-
-            function_objects[function_dir.name] = {
-                time_dir.name: sorted(
-                    (path for path in time_dir.iterdir() if path.is_file()),
-                    key=lambda path: path.name,
-                )
-                for time_dir in time_dirs
-            }
+            direct_outputs = self._files_by_time_directory(function_dir)
+            if direct_outputs:
+                function_objects[function_dir.name] = direct_outputs
+
+            # Multi-region function objects often add one extra nesting level:
+            # postProcessing/<region>/<functionObject>/<time>/...
+            for nested_function_dir in filter(Path.is_dir, function_dir.iterdir()):
+                nested_outputs = self._files_by_time_directory(nested_function_dir)
+                if nested_outputs:
+                    function_objects[
+                        f"{function_dir.name}/{nested_function_dir.name}"
+                    ] = nested_outputs
 
         return function_objects
 
     def _time_dirs_for_function_object(self, fo_folder: Path) -> list[Path]:
         return list(filter(Path.is_dir, fo_folder.iterdir()))
 
+    def _files_by_time_directory(self, fo_folder: Path) -> dict[str, list[Path]]:
+        """Return a time->files mapping when *fo_folder* has standard output."""
+        time_dirs = self._time_dirs_for_function_object(fo_folder)
+        outputs = {
+            time_dir.name: sorted(
+                (path for path in time_dir.iterdir() if path.is_file()),
+                key=lambda path: path.name,
+            )
+            for time_dir in time_dirs
+        }
+
+        # Only treat the folder as a function-object output when at least one
+        # time directory contains files.
+        return {time: files for time, files in outputs.items() if files}
+
     # -- simple_function_object_reader ------------------------------------
 
     @overload
@@ -160,6 +178,8 @@ def simple_function_object_reader(
                 at_time=at_time,
             )
 
+        function_object_name = function_object_name.strip("/")
+
         function_objects = self.discover_function_objects()
 
         if function_object_name not in function_objects:
diff --git a/tests/flowboost/openfoam/test_data_unit.py b/tests/flowboost/openfoam/test_data_unit.py
index 8789b15..f75d107 100644
--- a/tests/flowboost/openfoam/test_data_unit.py
+++ b/tests/flowboost/openfoam/test_data_unit.py
@@ -196,3 +196,42 @@ def test_simple_reader_loads_single_extensionless_output(self, tmp_path):
             {"column_1": 0.1, "column_2": 1.0},
             {"column_1": 0.2, "column_2": 2.0},
         ]
+
+    def test_discovers_multiregion_function_objects(self, tmp_path):
+        fo_file = (
+            tmp_path
+            / "postProcessing"
+            / "fluid"
+            / "cylinderT"
+            / "0"
+            / "surfaceFieldValue.dat"
+        )
+        fo_file.parent.mkdir(parents=True)
+        fo_file.write_text("# Time\tareaAverage(T)\n0.1\t297.0\n0.2\t298.0\n")
+
+        data = PolarsData(path=tmp_path)
+        discovered = data.discover_function_objects()
+
+        assert discovered["fluid/cylinderT"]["0"] == [fo_file]
+
+    def test_simple_reader_loads_multiregion_function_object(self, tmp_path):
+        fo_file = (
+            tmp_path
+            / "postProcessing"
+            / "fluid"
+            / "cylinderT"
+            / "0"
+            / "surfaceFieldValue.dat"
+        )
+        fo_file.parent.mkdir(parents=True)
+        fo_file.write_text("# Time\tareaAverage(T)\n0.1\t297.0\n0.2\t298.0\n")
+
+        data = PolarsData(path=tmp_path)
+        df = data.simple_function_object_reader("/fluid/cylinderT")
+
+        assert df is not None
+        assert df.columns == ["Time", "areaAverage(T)"]
+        assert df.to_dicts() == [
+            {"Time": 0.1, "areaAverage(T)": 297.0},
+            {"Time": 0.2, "areaAverage(T)": 298.0},
+        ]

From 2a61ea580bc317cdbaa4a84933b59295210bbf3b Mon Sep 17 00:00:00 2001
From: blttkgl <buluttekgul@gmail.com>
Date: Wed, 13 May 2026 14:40:58 +0300
Subject: [PATCH 2/2] delete dummy tutorial

---
 .../coolingCylinder2D/coolingCylinder2D.py    | 94 -------------------
 1 file changed, 94 deletions(-)
 delete mode 100644 examples/coolingCylinder2D/coolingCylinder2D.py

diff --git a/examples/coolingCylinder2D/coolingCylinder2D.py b/examples/coolingCylinder2D/coolingCylinder2D.py
deleted file mode 100644
index e57fb3b..0000000
--- a/examples/coolingCylinder2D/coolingCylinder2D.py
+++ /dev/null
@@ -1,94 +0,0 @@
-from __future__ import annotations
-
-import warnings
-from pathlib import Path
-
-import coloredlogs
-import polars as pl
-
-from flowboost import (
-    Case,
-    Constraint,
-    Dictionary,
-    Dimension,
-    Manager,
-    Objective,
-    Session,
-)
-
-def averageT(case: Case):
-    """Calculate the lift to drag ratio from simulation results."""
-    dataframe = case.data.simple_function_object_reader("fluid/cylinderT")
-
-    if dataframe is None:
-        return None
-    return (
-        dataframe.select(pl.last("areaAverage(T)")).item()
-    )
-
-
-
-
-
-if __name__ == "__main__":
-    coloredlogs.install(level="INFO")
-
-    # --- Session ---
-    session = Session(
-        name="coolingCylinder2D",
-        data_dir=Path("flowboost_data"),
-        clone_method="copy",
-        max_evaluations=50,
-        bo_concurrency=3
-    )
-
-    # --- Template case ---
-    cooling_case = Case.from_tutorial(
-        "multiRegion/CHT/coolingCylinder2D",
-        Path(session.data_dir, "coolingCylinder2D_template"),
-        method="copy",
-    )
-    cooling_case.dictionary("system/controlDict").entry("writeInterval").set("20")
-
-    session.attach_template_case(case=cooling_case)
-
-    # --- Objectives ---
-
-    objective = Objective(
-        name="averageT",
-        minimize=False,
-        objective_function=averageT,
-    )
-
-
-
-    # --- Search space ---
-    DICT_FILE = "system/blockMeshDict"
-
-    radius_dim = Dimension.range(
-        name="cylinderRadius",
-        link=Dictionary.link(DICT_FILE).entry("cylinderRadius"),
-        lower=-0.001,
-        upper=0.01,
-    )
-
-
-
-    session.configure_optimization(
-        objectives=[objective],
-        search_space=[radius_dim]
-    )
-
-    # --- Job manager ---
-    session.job_manager = session.job_manager or Manager.create(
-        scheduler="Local",
-        wdir=session.data_dir,
-        job_limit=1,
-    )
-    session.job_manager.monitoring_interval = 10
-
-    # --- Run ---
-    session.backend.initialization_trials = 10
-    session.clean_pending_cases()
-    session.start()
-