Feature: use CMake File API (#9005)

* - use CMake File API

Signed-off-by: SSE4 <tomskside@gmail.com>

* Update conan/tools/cmake/file_api.py

* Update conan/tools/cmake/file_api.py

* Update conan/tools/cmake/file_api.py

* Update conans/model/cpp_package.py

* Update conans/model/cpp_package.py

* Update conans/model/cpp_package.py

* Update conans/model/cpp_package.py

* Update conans/model/cpp_package.py

* Update conans/model/cpp_package.py

* Update conans/model/cpp_package.py

* Update conans/model/cpp_package.py

* Update conans/model/cpp_package.py

* review

* Update conans/test/functional/toolchains/cmake/test_file_api.py

* Update conans/test/functional/toolchains/cmake/test_file_api.py

* Update conans/test/functional/toolchains/cmake/test_file_api.py

* Update conan/tools/files/cpp_package.py

* - process only known target types

Signed-off-by: SSE4 <tomskside@gmail.com>

Co-authored-by: memsharded <james@conan.io>

conan/tools/cmake/__init__.py

@@ -1,3 +1,4 @@
 from conan.tools.cmake.toolchain import CMakeToolchain
 from conan.tools.cmake.cmake import CMake
 from conan.tools.cmake.cmakedeps.cmakedeps import CMakeDeps
+from conan.tools.cmake.file_api import CMakeFileAPI

conan/tools/cmake/file_api.py

@@ -0,0 +1,144 @@
+import json
+import fnmatch
+import os
+
+from conan.tools.files import CppPackage
+from conans.util.files import save, load
+
+
+class CMakeFileAPI(object):
+    """
+    implements https://cmake.org/cmake/help/latest/manual/cmake-file-api.7.html
+    """
+    CODEMODELV2 = "codemodel-v2"
+    SKIP_TARGETS = ["ZERO_CHECK", "ALL_BUILD"]
+    # https://cmake.org/cmake/help/v3.21/prop_tgt/TYPE.html
+    SUPPORTED_TARGET_TYPES = ['STATIC_LIBRARY', 'SHARED_LIBRARY', 'MODULE_LIBRARY']
+
+    def __init__(self, conanfile):
+        self._conanfile = conanfile
+
+    @property
+    def api_dir(self):
+        """
+        :return: api directory <build>/.cmake/api/v1/
+        """
+        return os.path.join(self._conanfile.build_folder, ".cmake", "api", "v1")
+
+    @property
+    def query_dir(self):
+        """
+        :return: api query sub-directory <build>/.cmake/api/v1/query
+        """
+        return os.path.join(self.api_dir, "query")
+
+    @property
+    def reply_dir(self):
+        """
+        :return: api reply sub-directory <build>/.cmake/api/v1/reply
+        """
+        return os.path.join(self.api_dir, "reply")
+
+    def query(self, query):
+        """
+        prepare the CMake File API query (the actual query will be done during the configure step)
+        :param query: type of the CMake File API query (e.g. CODEMODELV2)
+        :return: new query object
+        """
+        if query == self.CODEMODELV2:
+            # implements codemodel-v2 query
+            # https://cmake.org/cmake/help/latest/manual/cmake-file-api.7.html#codemodel-version-2
+            os.makedirs(self.query_dir)
+            save(os.path.join(self.query_dir, "codemodel-v2"), "")
+            return
+        raise NotImplementedError()
+
+    def reply(self, reply):
+        """
+        obtain the CMake File API reply (which should have been made during the configure step)
+        :param reply: type of the CMake File API reply (e.g. CODEMODELV2)
+        :return: new reply object
+        """
+        if reply == self.CODEMODELV2:
+            return self.CodeModelReplyV2(self)
+        raise NotImplementedError()
+
+    @property
+    def build_type(self):
+        """
+        :return: active build type (configuration)
+        """
+        return self._conanfile.settings.get_safe("build_type")
+
+    class CodeModelReplyV2(object):
+        """
+        implements codemodel-v2 reply
+        https://cmake.org/cmake/help/latest/manual/cmake-file-api.7.html#codemodel-version-2
+        """
+        def __init__(self, api):
+
+            def loadjs(filename):
+                return json.loads(load(filename))
+
+            codemodels = os.listdir(api.reply_dir)
+            codemodels = [c for c in codemodels if fnmatch.fnmatch(c, "codemodel-v2-*.json")]
+            assert len(codemodels) == 1
+            self._codemodel = loadjs(os.path.join(api.reply_dir, codemodels[0]))
+
+            self._configurations = dict()
+            for configuration in self._codemodel['configurations']:
+                if configuration["name"] != api.build_type:
+                    continue
+
+                self._components = dict()
+                for target in configuration["targets"]:
+                    if target['name'] in CMakeFileAPI.SKIP_TARGETS:
+                        continue
+                    self._components[target["name"]] = \
+                        loadjs(os.path.join(api.reply_dir, target['jsonFile']))
+
+        @classmethod
+        def _name_on_disk2lib(cls, name_on_disk):
+            """
+            convert raw library file name into conan-friendly one
+            :param name_on_disk: raw library file name read from target.json
+            :return: conan-friendly library name, without suffix and prefix
+            """
+            if name_on_disk.endswith('.lib'):
+                return name_on_disk[:-4]
+            elif name_on_disk.endswith('.dll'):
+                return name_on_disk[:-4]
+            elif name_on_disk.startswith('lib') and name_on_disk.endswith('.a'):
+                return name_on_disk[3:-2]
+            else:
+                # FIXME: This fails to parse executables
+                raise Exception("don't know how to convert %s" % name_on_disk)
+
+        @classmethod
+        def _parse_dep_name(cls, name):
+            """
+            :param name: extract dependency name from the id like 'decoder::@5310dfab9e417c587352'
+            :return: dependency name (part before ::@ token)
+            """
+            return name.split("::@")[0]
+
+        def to_conan_package(self):
+            """
+            converts codemodel-v2 into conan_package.json object
+            :return: ConanPackage instance
+            """
+
+            conan_package = CppPackage()
+
+            for name, target in self._components.items():
+                if target['type'] not in CMakeFileAPI.SUPPORTED_TARGET_TYPES:
+                    continue
+                component = conan_package.add_component(name)
+                # TODO: CMakeDeps has nothing to do here
+                component.names["CMakeDeps"] = name
+                component.libs = [self._name_on_disk2lib(target['nameOnDisk'])]
+                deps = target["dependencies"] if 'dependencies' in target else []
+                deps = [self._parse_dep_name(d['id']) for d in deps]
+                component.requires = [d for d in deps if d not in CMakeFileAPI.SKIP_TARGETS]
+
+            return conan_package

conan/tools/files/__init__.py

@@ -1,3 +1,4 @@
 from conan.tools.files.files import load, save, mkdir, ftp_download, download, get, rename, \
     load_build_json, save_build_json
 from conan.tools.files.patches import patch, apply_conandata_patches
+from conan.tools.files.cpp_package import CppPackage

conan/tools/files/cpp_package.py

@@ -0,0 +1,73 @@
+import json
+from conans.util.files import load, save
+
+
+class CppPackage(object):
+    """
+    models conan_package.json, serializable object
+    """
+
+    DEFAULT_FILENAME = "cpp_package.json"
+
+    def __init__(self):
+        self.components = dict()
+
+    @classmethod
+    def load(cls, filename=DEFAULT_FILENAME):
+        """
+        loads package model into memory from the conan_package.json file
+        :param filename: path to the cpp_package.json
+        :return: a new instance of CppPackage
+        """
+        def from_json(o):
+            if "components" in o:
+                return {n: CppPackage.Component(c) for n, c in o["components"].items()}
+            else:
+                return o
+        conan_package = CppPackage()
+        conan_package.components = json.loads(load(filename), object_hook=from_json)
+        return conan_package
+
+    def save(self, filename=DEFAULT_FILENAME):
+        """
+        saves package model from memory into the cpp_package.json file
+        :param filename: path to the cpp_package.json
+        :return: None
+        """
+        text = json.dumps(self, default=lambda o: o.__dict__, indent=4)
+        save(filename, text)
+
+    def package_info(self, conanfile):
+        """
+        performs an automatically generated package_info method on conanfile, populating
+        conanfile.package_info with the information available inside cpp_package.json
+        :return: None
+        """
+        for cname, component in self.components.items():
+            conanfile.cpp_info.components[cname].libs = component.libs
+            conanfile.cpp_info.components[cname].requires = component.requires
+            for generator, gname in component.names.items():
+                conanfile.cpp_info.components[cname].set_property("cmake_target_name", gname, generator)
+
+    def add_component(self, name):
+        """
+        appens a new CppPackage.Configuration into the internal dictionary
+        :param name: name of the given configuration (e.g. Debug)
+        :return: a new CppPackage.Configuration instance (empty)
+        """
+        self.components[name] = CppPackage.Component()
+        return self.components[name]
+
+    class Component(object):
+        """
+        represents a single component (aka target) within package configuration
+        """
+        def __init__(self, values=None):
+            if values:
+                self.names = values["names"]
+                self.requires = values["requires"]
+                self.libs = values["libs"]
+            else:
+                self.names = dict()
+                self.requires = []
+                self.libs = []

conans/test/assets/cmake.py

@@ -5,7 +5,7 @@
 
 def gen_cmakelists(language="CXX", verify=True, project="project", libname="mylibrary",
                    libsources=None, appname="myapp", appsources=None, cmake_version="3.15",
-                   install=False, find_package=None, libtype=""):
+                   install=False, find_package=None, libtype="", deps=None, public_header=None):
     """
     language: C, C++, C/C++
     project: the project name
@@ -21,17 +21,31 @@ def gen_cmakelists(language="CXX", verify=True, project="project", libname="myli
         cmake_minimum_required(VERSION {{cmake_version}})
         project({{project}} {{language}})
 
+        {% if find_package is mapping %}
+        {% for s, c in find_package.items() %}
+        find_package({{s}} COMPONENTS {{c}} )
+        {% endfor %}
+        {% else %}
         {% for s in find_package %}
         find_package({{s}})
         {% endfor %}
+        {% endif %}
 
         {% if libsources %}
         add_library({{libname}} {{libtype}} {% for s in libsources %} {{s}} {% endfor %})
         {% endif %}
 
         {% if libsources and find_package %}
+        {% if find_package is mapping %}
+        target_link_libraries({{libname}} {% for s, c in find_package.items() %} {{s}}::{{c}} {% endfor %})
+        {% else %}
         target_link_libraries({{libname}} {% for s in find_package %} {{s}}::{{s}} {% endfor %})
         {% endif %}
+        {% endif %}
+
+        {% if libsources and deps %}
+        target_link_libraries({{libname}} {% for s in deps %} {{s}} {% endfor %})
+        {% endif %}
 
         {% if appsources %}
         add_executable({{appname}} {% for s in appsources %} {{s}} {% endfor %})
@@ -42,11 +56,37 @@ def gen_cmakelists(language="CXX", verify=True, project="project", libname="myli
         {% endif %}
 
         {% if appsources and not libsources and find_package %}
+        {% if find_package is mapping %}
+         target_link_libraries({{appname}} {% for s, c in find_package.items() %} {{s}}::{{c}} {% endfor %})
+        {% else %}
         target_link_libraries({{appname}} {% for s in find_package %} {{s}}::{{s}} {% endfor %})
         {% endif %}
+        {% endif %}
+
+        {% if appsources and deps %}
+        target_link_libraries({{appname}} {% for s in deps %} {{s}} {% endfor %})
+        {% endif %}
+
+        {% if libsources and public_header %}
+        set_target_properties({{libname}} PROPERTIES PUBLIC_HEADER "{{public_header}}")
+        {% endif %}
 
         {% if install %}
-        install(TARGETS {{appname}} {{libname}} DESTINATION ".")
+        {% if appsources %}
+        install(TARGETS {{appname}} DESTINATION ".")
+        {% endif %}
+        {% if libsources %}
+        install(TARGETS {{libname}} DESTINATION "."
+        {% if public_header %}
+        PUBLIC_HEADER DESTINATION include
+        {% endif %}
+        RUNTIME DESTINATION bin
+        ARCHIVE DESTINATION lib
+        LIBRARY DESTINATION lib
+        FRAMEWORK DESTINATION Frameworks
+        BUNDLE DESTINATION bin
+        )
+        {% endif %}
         {% endif %}
         """)
 
@@ -61,5 +101,7 @@ def gen_cmakelists(language="CXX", verify=True, project="project", libname="myli
                      "cmake_version": cmake_version,
                      "install": install,
                      "find_package": find_package or [],
-                     "libtype": libtype
+                     "libtype": libtype,
+                     "public_header": public_header,
+                     "deps": deps,
                      })