[onert/python] Introduce BaseSession (#14527)

This commit introduces the class BaseSession.
  - Inroduce the class BaseSession to group common functionalities
  - Modify setup.py to make Python files easier to find.

ONE-DCO-1.0-Signed-off-by: ragmani <[email protected]>

Author: ragmani

infra/nnfw/python/setup.py

@@ -52,12 +52,23 @@
 
     # copy *py files to package_directory
     PY_DIR = os.path.join(THIS_FILE_DIR, '../../../runtime/onert/api/python/package')
-    for py_file in os.listdir(PY_DIR):
-        if py_file.endswith(".py"):
-            src_path = os.path.join(PY_DIR, py_file)
-            dest_path = os.path.join(THIS_FILE_DIR, package_directory)
-            shutil.copy(src_path, dest_path)
-            print(f"Copied '{src_path}' to '{dest_path}'")
+    for root, dirs, files in os.walk(PY_DIR):
+        # Calculate the relative path from the source directory
+        rel_path = os.path.relpath(root, PY_DIR)
+        dest_dir = os.path.join(THIS_FILE_DIR, package_directory)
+        dest_sub_dir = os.path.join(dest_dir, rel_path)
+        print(f"dest_sub_dir '{dest_sub_dir}'")
+
+        # Ensure the corresponding destination subdirectory exists
+        os.makedirs(dest_sub_dir, exist_ok=True)
+
+        # Copy only .py files
+        for py_file in files:
+            if py_file.endswith(".py"):
+                src_path = os.path.join(root, py_file)
+                # dest_path = os.path.join(THIS_FILE_DIR, package_directory)
+                shutil.copy(src_path, dest_sub_dir)
+                print(f"Copied '{src_path}' to '{dest_sub_dir}'")
 
     # remove architecture directory
     if os.path.exists(package_directory):
@@ -142,6 +153,6 @@ def get_directories():
       url='https://github.com/Samsung/ONE',
       license='Apache-2.0, MIT, BSD-2-Clause, BSD-3-Clause, Mozilla Public License 2.0',
       has_ext_modules=lambda: True,
-      packages=[package_directory],
+      packages=find_packages(),
       package_data={package_directory: so_list},
       install_requires=['numpy >= 1.19'])

runtime/onert/api/python/package/__init__.py

@@ -1,2 +1,8 @@
-__all__ = ['infer']
+# Define the public API of the onert package
+__all__ = ["infer", "tensorinfo"]
+
+# Import and expose the infer module's functionalities
 from . import infer
+
+# Import and expose tensorinfo
+from .common import tensorinfo as tensorinfo

runtime/onert/api/python/package/common/__init__.py

@@ -0,0 +1,3 @@
+from .basesession import BaseSession, tensorinfo
+
+__all__ = ["BaseSession", "tensorinfo"]

runtime/onert/api/python/package/common/basesession.py

@@ -0,0 +1,75 @@
+import numpy as np
+
+from ..native import libnnfw_api_pybind
+
+
+def num_elems(tensor_info):
+    """Get the total number of elements in nnfw_tensorinfo.dims."""
+    n = 1
+    for x in range(tensor_info.rank):
+        n *= tensor_info.dims[x]
+    return n
+
+
+class BaseSession:
+    """
+    Base class providing common functionality for inference and training sessions.
+    """
+    def __init__(self, backend_session):
+        """
+        Initialize the BaseSession with a backend session.
+        Args:
+            backend_session: A backend-specific session object (e.g., nnfw_session).
+        """
+        self.session = backend_session
+        self.inputs = []
+        self.outputs = []
+
+    def __getattr__(self, name):
+        """
+        Delegate attribute access to the bound NNFW_SESSION instance.
+        Args:
+            name (str): The name of the attribute or method to access.
+        Returns:
+            The attribute or method from the bound NNFW_SESSION instance.
+        """
+        return getattr(self.session, name)
+
+    def set_inputs(self, size, inputs_array=[]):
+        """
+        Set the input tensors for the session.
+        Args:
+            size (int): Number of input tensors.
+            inputs_array (list): List of numpy arrays for the input data.
+        """
+        for i in range(size):
+            input_tensorinfo = self.session.input_tensorinfo(i)
+
+            if len(inputs_array) > i:
+                input_array = np.array(inputs_array[i], dtype=input_tensorinfo.dtype)
+            else:
+                print(
+                    f"Model's input size is {size}, but given inputs_array size is {len(inputs_array)}.\n{i}-th index input is replaced by an array filled with 0."
+                )
+                input_array = np.zeros((num_elems(input_tensorinfo)),
+                                       dtype=input_tensorinfo.dtype)
+
+            self.session.set_input(i, input_array)
+            self.inputs.append(input_array)
+
+    def set_outputs(self, size):
+        """
+        Set the output tensors for the session.
+        Args:
+            size (int): Number of output tensors.
+        """
+        for i in range(size):
+            output_tensorinfo = self.session.output_tensorinfo(i)
+            output_array = np.zeros((num_elems(output_tensorinfo)),
+                                    dtype=output_tensorinfo.dtype)
+            self.session.set_output(i, output_array)
+            self.outputs.append(output_array)
+
+
+def tensorinfo():
+    return libnnfw_api_pybind.infer.nnfw_tensorinfo()

runtime/onert/api/python/package/infer.py

@@ -0,0 +1,3 @@
+from .session import session
+
+__all__ = ["session"]

runtime/onert/api/python/package/infer/__init__.py

@@ -0,0 +1,27 @@
+from ..native import libnnfw_api_pybind
+from ..common.basesession import BaseSession
+
+
+class session(BaseSession):
+    """
+    Class for inference using nnfw_session.
+    """
+    def __init__(self, nnpackage_path, backends="cpu"):
+        """
+        Initialize the inference session.
+        Args:
+            nnpackage_path (str): Path to the nnpackage file or directory.
+            backends (str): Backends to use, default is "cpu".
+        """
+        super().__init__(libnnfw_api_pybind.infer.nnfw_session(nnpackage_path, backends))
+        self.session.prepare()
+        self.set_outputs(self.session.output_size())
+
+    def inference(self):
+        """
+        Perform model and get outputs
+        Returns:
+            list: Outputs from the model.
+        """
+        self.session.run()
+        return self.outputs