conan-center-index/docs/package_templates/cmake_package/all/conanfile.py

from conan import ConanFile
from conan.errors import ConanInvalidConfiguration
from conan.tools.microsoft import check_min_vs, is_msvc_static_runtime, is_msvc
from conan.tools.files import apply_conandata_patches, export_conandata_patches, get, copy, rm, rmdir, replace_in_file
from conan.tools.build import check_min_cppstd
from conan.tools.scm import Version
from conan.tools.cmake import CMake, CMakeDeps, CMakeToolchain, cmake_layout
from conan.tools.env import VirtualBuildEnv
import os


required_conan_version = ">=1.53.0"

#
# INFO: Please, remove all comments before pushing your PR!
#


class PackageConan(ConanFile):
    name = "package"
    description = "short description"
    # Use short name only, conform to SPDX License List: https://spdx.org/licenses/
    # In case not listed there, use "LicenseRef-<license-file-name>"
    license = ""
    url = "https://github.com/conan-io/conan-center-index"
    homepage = "https://github.com/project/package"
    # no "conan" and project name in topics. Use topics from the upstream listed on GH
    topics = ("topic1", "topic2", "topic3")
    settings = "os", "arch", "compiler", "build_type"
    options = {
        "shared": [True, False],
        "fPIC": [True, False],
    }
    default_options = {
        "shared": False,
        "fPIC": True,
    }

    @property
    def _min_cppstd(self):
        return 17

    # in case the project requires C++14/17/20/... the minimum compiler version should be listed
    @property
    def _compilers_minimum_version(self):
        return {
            "gcc": "7",
            "clang": "7",
            "apple-clang": "10",
        }

    # no exports_sources attribute, but export_sources(self) method instead
    # this allows finer grain exportation of patches per version
    def export_sources(self):
        export_conandata_patches(self)

    def config_options(self):
        if self.settings.os == "Windows":
            del self.options.fPIC

    def configure(self):
        if self.options.shared:
            self.options.rm_safe("fPIC")
        # for plain C projects only
        self.settings.rm_safe("compiler.libcxx")
        self.settings.rm_safe("compiler.cppstd")

    def layout(self):
        # src_folder must use the same source folder name the project
        cmake_layout(self, src_folder="src")

    def requirements(self):
        # prefer self.requires method instead of requires attribute
        self.requires("dependency/0.8.1")

    def validate(self):
        # validate the minimum cpp standard supported. For C++ projects only
        if self.info.settings.compiler.cppstd:
            check_min_cppstd(self, self._min_cppstd)
        check_min_vs(self, 191)
        if not is_msvc(self):
            minimum_version = self._compilers_minimum_version.get(str(self.info.settings.compiler), False)
            if minimum_version and Version(self.info.settings.compiler.version) < minimum_version:
                raise ConanInvalidConfiguration(
                    f"{self.ref} requires C++{self._min_cppstd}, which your compiler does not support."
                )
        # in case it does not work in another configuration, it should validated here too
        if is_msvc(self) and self.info.options.shared:
            raise ConanInvalidConfiguration(f"{self.ref} can not be built as shared on Visual Studio and msvc.")

    # if another tool than the compiler or CMake is required to build the project (pkgconf, bison, flex etc)
    def build_requirements(self):
        self.tool_requires("tool/x.y.z")

    def source(self):
        get(self, **self.conan_data["sources"][self.version], destination=self.source_folder, strip_root=True)

    def generate(self):
        # BUILD_SHARED_LIBS and POSITION_INDEPENDENT_CODE are automatically parsed when self.options.shared or self.options.fPIC exist
        tc = CMakeToolchain(self)
        # Boolean values are preferred instead of "ON"/"OFF"
        tc.variables["PACKAGE_CUSTOM_DEFINITION"] = True
        if is_msvc(self):
            # don't use self.settings.compiler.runtime
            tc.variables["USE_MSVC_RUNTIME_LIBRARY_DLL"] = not is_msvc_static_runtime(self)
        # deps_cpp_info, deps_env_info and deps_user_info are no longer used
        if self.dependencies["dependency"].options.foobar:
            tc.variables["DEPENDENCY_LIBPATH"] = self.dependencies["dependency"].cpp_info.libdirs
        # cache_variables should be used sparingly, example setting cmake policies
        tc.cache_variables["CMAKE_POLICY_DEFAULT_CMP0077"] = "NEW"
        tc.generate()
        # In case there are dependencies listed on requirements, CMakeDeps should be used
        tc = CMakeDeps(self)
        tc.generate()
        # In case there are dependencies listed on build_requirements, VirtualBuildEnv should be used
        tc = VirtualBuildEnv(self)
        tc.generate(scope="build")

    def _patch_sources(self):
        apply_conandata_patches(self)
        # remove bundled xxhash
        rm(self, "whateer.*", os.path.join(self.source_folder, "lib"))
        replace_in_file(self, os.path.join(self.source_folder, "CMakeLists.txt"), "...", "")

    def build(self):
        self._patch_sources()  # It can be apply_conandata_patches(self) only in case no more patches are needed
        cmake = CMake(self)
        cmake.configure()
        cmake.build()

    def package(self):
        copy(self, pattern="LICENSE", dst=os.path.join(self.package_folder, "licenses"), src=self.source_folder)
        cmake = CMake(self)
        cmake.install()

        # some files extensions and folders are not allowed. Please, read the FAQs to get informed.
        rmdir(self, os.path.join(self.package_folder, "lib", "pkgconfig"))
        rmdir(self, os.path.join(self.package_folder, "lib", "cmake"))
        rmdir(self, os.path.join(self.package_folder, "share"))
        rm(self, "*.la", os.path.join(self.package_folder, "lib"))
        rm(self, "*.pdb", os.path.join(self.package_folder, "lib"))
        rm(self, "*.pdb", os.path.join(self.package_folder, "bin"))

    def package_info(self):
        self.cpp_info.libs = ["package_lib"]

        # if package has an official FindPACKAGE.cmake listed in https://cmake.org/cmake/help/latest/manual/cmake-modules.7.html#find-modules
        # examples: bzip2, freetype, gdal, icu, libcurl, libjpeg, libpng, libtiff, openssl, sqlite3, zlib...
        self.cpp_info.set_property("cmake_module_file_name", "PACKAGE")
        self.cpp_info.set_property("cmake_module_target_name", "PACKAGE::PACKAGE")
        # if package provides a CMake config file (package-config.cmake or packageConfig.cmake, with package::package target, usually installed in <prefix>/lib/cmake/<package>/)
        self.cpp_info.set_property("cmake_file_name", "package")
        self.cpp_info.set_property("cmake_target_name", "package::package")
        # if package provides a pkgconfig file (package.pc, usually installed in <prefix>/lib/pkgconfig/)
        self.cpp_info.set_property("pkg_config_name", "package")

        # If they are needed on Linux, m, pthread and dl are usually needed on FreeBSD too
        if self.settings.os in ["Linux", "FreeBSD"]:
            self.cpp_info.system_libs.append("m")
            self.cpp_info.system_libs.append("pthread")
            self.cpp_info.system_libs.append("dl")

        # TODO: to remove in conan v2 once cmake_find_package_* generators removed
        self.cpp_info.filenames["cmake_find_package"] = "PACKAGE"
        self.cpp_info.filenames["cmake_find_package_multi"] = "package"
        self.cpp_info.names["cmake_find_package"] = "PACKAGE"
        self.cpp_info.names["cmake_find_package_multi"] = "package"