opencv · asmorkalov · May 26, 2023 · Jul 6, 2021 · Aug 17, 2021 · Aug 18, 2021
diff --git a/cmake/OpenCVDetectPython.cmake b/cmake/OpenCVDetectPython.cmake
@@ -297,3 +297,10 @@ elseif(PYTHON3_EXECUTABLE AND PYTHON3INTERP_FOUND)
     set(PYTHON_DEFAULT_AVAILABLE "TRUE")
     set(PYTHON_DEFAULT_EXECUTABLE "${PYTHON3_EXECUTABLE}")
 endif()
+
+if(PYTHON_DEFAULT_AVAILABLE)
+  execute_process(COMMAND ${PYTHON_DEFAULT_EXECUTABLE} --version
+                  OUTPUT_VARIABLE PYTHON_DEFAULT_VERSION
+                  OUTPUT_STRIP_TRAILING_WHITESPACE)
+  string(REGEX MATCH "[0-9]+.[0-9]+.[0-9]+" PYTHON_DEFAULT_VERSION "${PYTHON_DEFAULT_VERSION}")
+endif()
diff --git a/modules/python/bindings/CMakeLists.txt b/modules/python/bindings/CMakeLists.txt
@@ -76,18 +76,25 @@ set(cv2_generat
8000
ed_files
 
 string(REPLACE ";" "\n" opencv_hdrs_ "${opencv_hdrs}")
 file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/headers.txt" "${opencv_hdrs_}")
+file(GLOB_RECURSE typing_stubs_generation_files "${PYTHON_SOURCE_DIR}/src2/typing_stubs_generation/*.py")
 add_custom_command(
     OUTPUT ${cv2_generated_files}
     COMMAND "${PYTHON_DEFAULT_EXECUTABLE}" "${PYTHON_SOURCE_DIR}/src2/gen2.py" "${CMAKE_CURRENT_BINARY_DIR}" "${CMAKE_CURRENT_BINARY_DIR}/headers.txt"
     DEPENDS "${PYTHON_SOURCE_DIR}/src2/gen2.py"
             "${PYTHON_SOURCE_DIR}/src2/hdr_parser.py"
+            "${typing_stubs_generation_files}"
+            "${PYTHON_SOURCE_DIR}/src2/typing_stubs_generator.py"
             # not a real build dependency (file(WRITE) result): ${CMAKE_CURRENT_BINARY_DIR}/headers.txt
             ${opencv_hdrs}
     COMMENT "Generate files for Python bindings and documentation"
 )
 
 add_custom_target(gen_opencv_python_source DEPENDS ${cv2_generated_files})
 
+if(TARGET copy_opencv_typing_stubs)
+  add_dependencies(copy_opencv_typing_stubs gen_opencv_python_source)
+endif()
+
 set(cv2_custom_hdr "${CMAKE_CURRENT_BINARY_DIR}/pyopencv_custom_headers.h")
 set(cv2_custom_hdr_str "//user-defined headers\n")
 foreach(uh ${opencv_userdef_hdrs})

diff --git a/modules/python/common.cmake b/modules/python/common.cmake
@@ -34,6 +34,11 @@ if(TARGET gen_opencv_python_source)
   add_dependencies(${the_module} gen_opencv_python_source)
 endif()
 
+if(TARGET copy_opencv_typing_stubs)
+  # Python 3.6+
+  add_dependencies(${the_module} copy_opencv_typing_stubs)
+endif()
+
 ocv_assert(${PYTHON}_VERSION_MAJOR)
 ocv_assert(${PYTHON}_VERSION_MINOR)
 

diff --git a/modules/python/package/setup.py b/modules/python/package/setup.py
@@ -1,9 +1,19 @@
 import os
-import sys
-import platform
 import setuptools
 
-SCRIPT_DIR=os.path.dirname(os.path.abspath(__file__))
+
+SCRIPT_DIR = os.path.dirname(os.path.abspath(__file__))
+
+
+def collect_module_typing_stub_files(root_module_path):
+    stub_files = []
+    for module_path, _, files in os.walk(root_module_path):
+        stub_files.extend(
+            map(lambda p: os.path.join(module_path, p),
+                filter(lambda f: f.endswith(".pyi"), files))
+        )
+    return stub_files
+
 
 def main():
     os.chdir(SCRIPT_DIR)
@@ -13,6 +23,13 @@ def main():
 
     long_description = 'Open Source Computer Vision Library Python bindings'  # TODO
 
+    root_module_path = os.path.join(SCRIPT_DIR, "cv2")
+    py_typed_path = os.path.join(root_module_path, "py.typed")
+    if os.path.isfile(py_typed_path):
+        typing_stub_files = collect_module_typing_stub_files(root_module_path)
+        if len(typing_stub_files) > 0:
+            typing_stub_files.append(py_typed_path)
+
     setuptools.setup(
         name=package_name,
         version=package_version,
@@ -22,6 +39,9 @@ def main():
         long_description=long_description,
         long_description_content_type="text/markdown",
         packages=setuptools.find_packages(),
+        package_data={
+            "cv2": typing_stub_files
+        },
         maintainer="OpenCV Team",
         install_requires="numpy",
         classifiers=[
@@ -55,5 +75,6 @@ def main():
         ],
     )
 
+
 if __name__ == '__main__':
    main()
diff --git a/modules/python/python_loader.cmake b/modules/python/python_loader.cmake
@@ -45,8 +45,6 @@ foreach(fname ${PYTHON_LOADER_FILES})
   endif()
 endforeach()
 
-
-
 if(WIN32)
   if(CMAKE_GENERATOR MATCHES "Visual Studio")
     list(APPEND CMAKE_PYTHON_BINARIES_PATH "'${EXECUTABLE_OUTPUT_PATH}/Release'")  # TODO: CMAKE_BUILD_TYPE is not defined
@@ -126,3 +124,20 @@ if(NOT "${OPENCV_PYTHON_EXTRA_MODULES_PATH}" STREQUAL "")
     ocv_add_python_files_from_path(${extra_ocv_py_modules_path})
   endforeach()
 endif()
+
+if(${PYTHON}_VERSION_STRING VERSION_GREATER "3.6" AND PYTHON_DEFAULT_VERSION VERSION_GREATER "3.6")
+  add_custom_target(copy_opencv_typing_stubs)
+  # Copy all generated stub files to python_loader directory only if
+  # generation succeeds, this behvoir can't be achieved with default
+  # CMake constructions, because failed generation produces a warning instead of
+  # halts on hard error.
+  add_custom_command(
+    TARGET copy_opencv_typing_stubs
+    COMMAND ${PYTHON_DEFAULT_EXECUTABLE} ${PYTHON_SOURCE_DIR}/src2/copy_typings_stubs_on_success.py
+            --stubs_dir ${OPENCV_PYTHON_BINDINGS_DIR}/cv2
+            --output_dir ${__loader_path}/cv2
+  )
+  if(DEFINED OPENCV_PYTHON_INSTALL_PATH)
+    install(DIRECTORY "${OPENCV_PYTHON_BINDINGS_DIR}/cv2" DESTINATION "${OPENCV_PYTHON_INSTALL_PATH}" COMPONENT python)
+  endif()
+endif()
diff --git a/modules/python/src2/copy_typings_stubs_on_success.py b/modules/python/src2/copy_typings_stubs_on_success.py
@@ -0,0 +1,45 @@
+import argparse
+import warnings
+import os
+import sys
+
+if sys.version_info >= (3, 8, ):
+    # shutil.copytree received the `dirs_exist_ok` parameter
+    from functools import partial
+    import shutil
+
+    copy_tree = partial(shutil.copytree, dirs_exist_ok=True)
+else:
+    from distutils.dir_util import copy_tree
+
+
+def main():
+    args = parse_arguments()
+    py_typed_path = os.path.join(args.stubs_dir, 'py.typed')
+    if not os.path.isfile(py_typed_path):
+        warnings.warn(
+            '{} is missing, it means that typings stubs generation is either '
+            'failed or has been skipped. Ensure that Python 3.6+ is used for '
+            'build and there is no warnings during Python source code '
+            'generation phase.'.format(py_typed_path)
+        )
+        return
+    copy_tree(args.stubs_dir, args.output_dir)
+
+
+def parse_arguments():
+    parser = argparse.ArgumentParser(
+        description='Copies generated typing stubs only when generation '
+        'succeeded. This is identified by presence of the `py.typed` file '
+        'inside typing stubs directory.'
+    )
+    parser.add_argument('--stubs_dir', type=str,
+                        help='Path to directory containing generated typing '
+                        'stubs file')
+    parser.add_argument('--output_dir', type=str,
+                        help='Path to output directory')
+    return parser.parse_args()
+
+
+if __name__ == '__main__':
+    main()