restore python linters

.github/workflows/linter-conan-v2.yml

@@ -0,0 +1,124 @@
+name: "[linter] Conan v2 migration"
+
+on:
+  pull_request:
+
+env:
+  PYTHONPATH: ${{github.workspace}}
+  PYVER: "3.8"
+  REQUIREMENTS: "pylint==2.14"
+
+jobs:
+  test_linter:
+    name: Test linter changes (v2 migration)
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - name: Get changed files
+        uses: ./.github/actions/pr_changed_files
+        id: changed_files
+        with:
+          files: |
+            linter/**
+            .github/workflows/linter-conan-v2.yml
+
+      - name: Get Conan v2 version
+        id: parse_conan_v2_version
+        if: steps.changed_files.outputs.any_changed == 'true'
+        uses: mikefarah/yq@master
+        with:
+          cmd: yq '.conan.version' '.c3i/config_v2.yml'
+
+      - uses: actions/setup-python@v4
+        if: steps.changed_files.outputs.any_changed == 'true'
+        with:
+          python-version: ${{ env.PYVER }}
+
+      - name: Install requirements
+        if: steps.changed_files.outputs.any_changed == 'true'
+        run: |
+          pip install ${{ env.REQUIREMENTS }} conan==${{ steps.parse_conan_v2_version.outputs.result }}
+
+      - name: Execute linter over all recipes in the repository
+        id: linter_recipes
+        if: steps.changed_files.outputs.any_changed == 'true'
+        run: |
+          echo '## Linter summary (recipes)' >> $GITHUB_STEP_SUMMARY
+          pylint --rcfile=linter/pylintrc_recipe `ls recipes/*/*/conanfile.py | shuf -n 500` --output-format=json --output=recipes.json --score=y --exit-zero
+          jq '[map( select(.type=="error")) | group_by (.message)[] | {message: .[0].message, length: length}] | sort_by(.length) | reverse' recipes.json > recipes2.json
+          jq -r '.[] | " * \(.message): \(.length)"' recipes2.json >> $GITHUB_STEP_SUMMARY
+
+      - name: Execute linter over all test_package/recipes in the repository
+        id: linter_test_package
+        if: steps.changed_files.outputs.any_changed == 'true'
+        run: |
+          echo '## Linter summary (test_package)' >> $GITHUB_STEP_SUMMARY
+          pylint --rcfile=linter/pylintrc_testpackage `ls recipes/*/*/test_package/conanfile.py | shuf -n 500` --output-format=json --output=recipes.json --exit-zero
+          jq '[map( select(.type=="error")) | group_by (.message)[] | {message: .[0].message, length: length}] | sort_by(.length) | reverse' recipes.json > recipes2.json
+          jq -r '.[] | " * \(.message): \(.length)"' recipes2.json >> $GITHUB_STEP_SUMMARY
+
+  conanfile_recipe:
+    name: Lint changed conanfile.py (v2 migration)
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - name: Get changed files
+        id: changed-files
+        uses: ./.github/actions/pr_changed_files
+        with:
+          files: |
+            recipes/*/*/conanfile.py
+      - name: Get Conan v2 version
+        id: parse_conan_v2_version
+        if: steps.changed-files.outputs.any_changed == 'true'
+        uses: mikefarah/yq@master
+        with:
+          cmd: yq '.conan.version' '.c3i/config_v2.yml'
+      - uses: actions/setup-python@v4
+        if: steps.changed-files.outputs.any_changed == 'true'
+        with:
+          python-version: ${{ env.PYVER }}
+      - name: Install dependencies
+        if: steps.changed-files.outputs.any_changed == 'true'
+        run: |
+          pip install ${{ env.REQUIREMENTS }} conan==${{ steps.parse_conan_v2_version.outputs.result }}
+      - name: Run linter
+        if: steps.changed-files.outputs.any_changed == 'true'
+        run: |
+          echo "::add-matcher::linter/recipe_linter.json"
+          for file in ${{ steps.changed-files.outputs.all_changed_files }}; do
+            pylint --rcfile=linter/pylintrc_recipe --output-format=parseable ${file}
+          done
+
+  conanfile_test_package:
+    name: Lint changed test_package/conanfile.py (v2 migration)
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - name: Get changed files
+        id: changed-files
+        uses: ./.github/actions/pr_changed_files
+        with:
+          files: |
+            recipes/*/*/test_*/conanfile.py
+      - name: Get Conan v2 version
+        id: parse_conan_v2_version
+        if: steps.changed-files.outputs.any_changed == 'true'
+        uses: mikefarah/yq@master
+        with:
+          cmd: yq '.conan.version' '.c3i/config_v2.yml'
+      - uses: actions/setup-python@v4
+        if: steps.changed-files.outputs.any_changed == 'true'
+        with:
+          python-version: ${{ env.PYVER }}
+      - name: Install dependencies
+        if: steps.changed-files.outputs.any_changed == 'true'
+        run: |
+          pip install ${{ env.REQUIREMENTS }} conan==${{ steps.parse_conan_v2_version.outputs.result }}
+      - name: Run linter
+        if: steps.changed-files.outputs.any_changed == 'true'
+        run: |
+          echo "::add-matcher::linter/recipe_linter.json"
+          for file in ${{ steps.changed-files.outputs.all_changed_files }}; do
+            pylint --rcfile=linter/pylintrc_testpackage --ignore-paths="recipes/[^/]*/[^/]*/test_v2[^/]*/conanfile.py" --output-format=parseable ${file}
+          done

docs/linters.md

@@ -14,7 +14,12 @@ to configure plugins, warnings and errors which should be enabled or disabled.
 
   * [Understanding the different linters](#understanding-the-different-linters)
   * [Running the linters locally](#running-the-linters-locally)
-  * [Pylint configuration files](#pylint-configuration-files)<!-- endToc -->
+  * [Pylint configuration files](#pylint-configuration-files)
+  * [Linter Warning and Errors](#linter-warning-and-errors)
+    * [E9005 - conan-missing-name: Every conan recipe must contain the attribute name](#e9005---conan-missing-name-every-conan-recipe-must-contain-the-attribute-name)
+    * [E9007 - conan-test-no-name: Do not add name attribute in test package recipes](#e9007---conan-test-no-name-do-not-add-name-attribute-in-test-package-recipes)
+    * [E9011 - conan-import-tools: Importing conan.tools or conan.tools.xxx.zzz.yyy should be considered as private](#e9011---conan-import-tools-importing-conantools-or-conantoolsxxxzzzyyy-should-be-considered-as-private)
+    * [E9012 - conan-attr-version: Recipe should not contain version attribute](#e9012---conan-attr-version-recipe-should-not-contain-version-attribute)<!-- endToc -->
 
 ## Understanding the different linters
 
@@ -32,3 +37,79 @@ Check the [Developing Recipes](developing_recipes_locally.md) for more informati
 
 - [Pylint Recipe](../linter/pylintrc_recipe): This `rcfile` lists plugins and rules to be executed over all recipes (not test package) and validate them.
 - [Pylint Test Package Recipe](../linter/pylintrc_testpackage): This `rcfile` lists plugins and rules to be executed over all recipes in test package folders only:
+
+## Linter Warning and Errors
+
+Here is the list of current warning and errors provided by pylint, when using CCI configuration.
+
+### E9005 - conan-missing-name: Every conan recipe must contain the attribute name
+
+The attribute `name` is always expected. On the other hand, `version` should not be listed.
+
+```python
+def BazConanfile(ConanFile):
+    name = "baz"
+```
+
+### E9007 - conan-test-no-name: Do not add name attribute in test package recipes
+
+The test package is not a recipe, thus, it should not have a name
+
+```python
+def TestPackageConanFile(ConanFile):
+    name = "test_package" # Wrong!
+```
+
+### E9011 - conan-import-tools: Importing conan.tools or conan.tools.xxx.zzz.yyy should be considered as private
+
+Documented on [conanfile.tools](https://docs.conan.io/1/reference/conanfile/tools.html):
+It's not allowed to use `tools.xxx` directly:
+
+```python
+from conan import tools
+...
+
+tools.scm.Version(self.version)
+```
+
+Neither sub modules:
+
+```python
+from conan.tools.apple.apple import is_apple_os
+```
+
+Only modules under `conan.tools` and `conan.tools.xxx` are allowed:
+
+```python
+from conan.tools.files import rmdir
+from conan.tools import scm
+```
+
+### E9012 - conan-attr-version: Recipe should not contain version attribute
+
+All recipes on CCI should be generic enough to support as many versions as possible, so enforcing a specific
+version as attribute will not allow to re-use the same recipe for multiple release versions.
+
+```python
+from conan import ConanFile
+
+class FooConanFile(ConanFile):
+    version = "1.0.0"  # Wrong!
+```
+
+The package version should be passed as command argument, e.g:
+
+    conan create all/ 1.0.0@ -pr:h=default -pr:b=default
+
+Or, if you are running Conan 2.0:
+
+    conan create all/ --version=1.0.0 -pr:h=default -pr:b=default
+
+The only exception is when providing ``system`` packages, which are allowed.
+
+```python
+from conan import ConanFile
+
+class FooConanFile(ConanFile):
+    version = "system"  # Okay!
+```

docs/v2_migration.md

@@ -0,0 +1,147 @@
+# Preparing recipes for Conan 2.0
+
+This is expected for recipes to be updates in each pull request.
+
+- Updated helpers are expected, this is enforced by the [v2_linter](v2_linter.md)
+- Once a recipe publishes v2 packages, it must pass the v2 pipeline always.
+- The v2 pipeline with **is required** for changes to be merged.
+
+<!-- toc -->
+## Contents
+
+  * [Using Layout](#using-layout)
+    * [With New Generators](#with-new-generators)
+    * [With Multiple Build Helpers](#with-multiple-build-helpers)
+  * [CMakeToolchain](#cmaketoolchain)
+  * [New conf_info properties](#new-conf_info-properties)
+  * [New cpp_info set_property model](#new-cpp_info-set_property-model)
+    * [Translating .names information to cmake_target_name, cmake_module_target_name and cmake_file_name](#translating-names-information-to-cmake_target_name-cmake_module_target_name-and-cmake_file_name)
+    * [Translating .filenames information to cmake_file_name, cmake_module_file_name and cmake_find_mode](#translating-filenames-information-to-cmake_file_name-cmake_module_file_name-and-cmake_find_mode)
+    * [Translating .build_modules to cmake_build_modules](#translating-build_modules-to-cmake_build_modules)
+    * [PkgConfigDeps](#pkgconfigdeps)<!-- endToc -->
+
+> **Note**: Read about the [linter in pull requests](v2_linter.md) to learn how this is being enforced.
+
+It's time to start thinking seriously about Conan v2 and prepare recipes
+for the incoming changes. Conan v2 comes with many
+changes and improvements, you can read about them in the
+[Conan documentation](https://docs.conan.io/1/conan_v2.html).
+
+This document is a practical guide, offering extended information particular to Conan
+Center Index recipes to get them ready to upgrade to Conan 2.0.
+
+## Using Layout
+
+All recipes should use a layout. Without one, more manual configuration of folders (e.g. source, build, etc)
+and package structure will be required.
+
+### With New Generators
+
+When doing this there is no need to manually define `self._subfolder_[...]` in a recipe.
+Simply use `self.source_folder` and `self.build_folder` instead of "subfolder properties" that used to be the norm.
+
+### With Multiple Build Helpers
+
+When different build tools are use, at least one layout needs to be set.
+
+```python
+    def layout(self):
+        if self._use_cmake():
+            cmake_layout(self)
+        else: # using autotools
+            basic_layout(self)
+```
+
+The `src_folder` must be the same when using different layouts and should
+not depend on settings or options.
+
+## CMakeToolchain
+
+The old `CMake.definition` should be replaced by `CMakeToolchain.variables` and moved to the `generate` method.
+However, certain options need to be passed as `cache_variables`. You'll need to check project's `CMakeLists.txt`
+as there are a few cases to look out for:
+
+- When an `option` is configured before `project()` is called.
+
+  ```cmake
+  cmake_minimum_required(3.1)
+  option(BUILD_EXAMPLES "Build examples using foorbar")
+  project(foobar)
+  ```
+
+- When an variable is declared with `CACHE`.
+
+  ```cmake
+  cmake_minimum_required(3.1)
+  project(foobar)
+  set(USE_JPEG ON CACHE BOOL "include jpeg support?")
+  ```
+
+For more information refere to the [CMakeToolchain docs](https://docs.conan.io/1/reference/conanfile/tools/cmake/cmaketoolchain.html)
+or check out the converstaion in conan-io/conan#11937 for the brave.
+
+## New conf_info properties
+
+As described in the documentation `self.user_info` has been depreated and you are now required to use
+`self.conf_info` to define individual properties to expose to downstream recipes.
+The [2.0 migrations docs](https://docs.conan.io/1/migrating_to_2.0/recipes.html#removed-self-user-info)
+should cover the technical details, however for ConanCenterIndex we need to make sure there are no collisions
+`conf_info` must be named `user.<recipe_name>:<variable>`.
+
+For usage options of `conf_info`, the [documenation](https://docs.conan.io/1/reference/config_files/global_conf.html?highlight=conf_info#configuration-in-your-recipes)
+
+In ConanCenterIndex this will typically looks like:
+
+- defining a value
+  ```py
+      def package_info(self):
+          tool_path = os.path.join(self.package_folder, "bin", "tool")
+          self.conf_info.define("user.pkg:tool", tool_path)
+  ```
+- using a value
+  ```py
+      #generators = "VirtualBuildEnv", "VirtualRunEnv"
+
+      def build_requirements(self):
+          self.tool_requires("tool/0.1")
+
+      def build(self):
+          tool_path = self.conf_info.get("user.pkg:tool")
+          self.run(f"{tool_path} --build")
+  ```
+
+> **Note**: This should only be used when absolutely required. In the vast majority of cases, the new
+> ["Environments"](https://docs.conan.io/1/reference/conanfile/tools/env/environment.html?highlight=Virtual)
+> will include the `self.cpp_info.bindirs` which will provide access to the tools in the correct scopes.
+
+## New cpp_info set_property model
+
+New Conan generators like
+[CMakeDeps](https://docs.conan.io/1/reference/conanfile/tools/cmake/cmakedeps.html)
+and
+[PkgConfigDeps](https://docs.conan.io/1/reference/conanfile/tools/gnu/pkgconfigdeps.html),
+don't listen to `cpp_info`'s ``.names``, ``.filenames`` or ``.build_modules`` attributes.
+There is a new way of setting the `cpp_info` information with these
+generators using the ``set_property(property_name, value)`` method.
+
+Both of these two models **will live together in recipes** to make
+recipes compatible for both 1.x and 2.0 users. Deprecated feilds are not to be removed at this time.
+
+To understand the impact of these and the relation between different generates, refer to the
+[migrating properties](https://docs.conan.io/1/migrating_to_2.0/properties.html) documentation.
+
+### Translating .names information to cmake_target_name, cmake_module_target_name and cmake_file_name
+
+The variation of `names` is covered by the [Conan documentation](https://docs.conan.io/1/migrating_to_2.0/properties.html#migrating-from-names-to-cmake-target-name).
+
+### Translating .filenames information to cmake_file_name, cmake_module_file_name and cmake_find_mode
+
+As for `filenames`, refer to [this section](https://docs.conan.io/1/migrating_to_2.0/properties.html#migrating-from-filenames-to-cmake-file-name).
+
+### Translating .build_modules to cmake_build_modules
+
+The variation of `build_modules` is covered by the [Conan documentation](https://docs.conan.io/1/migrating_to_2.0/properties.html#translating-build-modules-to-cmake-build-modules).
+
+### PkgConfigDeps
+
+For migrating, `names` used with `pkg_config`, see [Conan documentation](https://docs.conan.io/1/migrating_to_2.0/properties.html#migration-from-names-to-pkg-config-name)