feat: Add bazel 7.1 documentation

Author: Wendel Johannes (XC-CP/PJ-ADC-ECI)

reference/tools/google/bazeldeps.rst

@@ -7,7 +7,9 @@ BazelDeps
 
 The ``BazelDeps`` is the dependencies generator for Bazel. Generates a *<REPOSITORY>/BUILD.bazel* file per dependency,
 where the *<REPOSITORY>/* folder is the Conan recipe reference name by default, e.g., *mypkg/BUILD.bazel*. Apart from
-that, it also generates a *dependencies.bzl* file which contains a Bazel function to load all your Conan dependencies.
+that, it also generates a *dependencies.bzl* file which contains a Bazel function to load all your Conan dependencies
+when using Bazel < 7 and the files conan_deps_module_extension.bzl and conan_deps_repo_rules.bzl for the usage with
+Bazel > 7.1 (7.0 is not supported right now).
 
 The ``BazelDeps`` generator can be used by name in conanfiles:
 
@@ -59,9 +61,12 @@ Every :command:`conan install` generates these files:
 
 * *BUILD.bazel*: An empty file aimed to be alongside the *dependencies.bzl* one.
   More information `here <https://bazel.build/concepts/build-files>`__.
-* *dependencies.bzl*: this file tells your Bazel *WORKSPACE* how to load the dependencies.
 * *zlib/BUILD.bazel*: contains all the targets that you can load from any of your *BUILD* files. More information in
   :ref:`conan_tools_google_bazeldeps_customization`.
+* *dependencies.bzl*: this file tells your Bazel *WORKSPACE* how to load the dependencies.
+* *conan_deps_module_extension.bzl*: this file is used to load each dependency as repository, in Bazel 7.1 and above.
+* *conan_deps_repo_rules.bzl*: The rule provided by this file is used to create a repository, in Bazel 7.1 and above.
+  It is not intended to be used by consumer, but by the conan_deps_module_extension.bzl.
 
 Let's check the content of the files created:
 
@@ -89,6 +94,45 @@ Given the example above, and imagining that your WORKSPACE is at the same direct
     load_conan_dependencies()
 
 
+.. code-block:: python
+    :caption conan_deps_module_extension.bzl
+
+    # This module provides a repo for each requires-dependency in your conanfile.
+    # It's generated by the ConanDepsGenerator, and should be used in your Module.bazel file.
+    load(":conan_deps_repo_rules.bzl", "conan_dependency_repo")
+
+    def _load_dependenies_impl(mctx):
+        conan_dependency_repo(
+            name = "zlib",
+            package_path = "/path/to/conan/package/folder/",
+            build_file_path = "/your/current/working/directory/zlib/BUILD.bazel",
+        )
+
+        return mctx.extension_metadata(
+            root_module_direct_deps = None,
+            root_module_direct_dev_deps = None,
+
+            # Prevent writing function content to lockfiles https://bazel.build/rules/lib/builtins/module_ctx#extension_metadata
+            # Important for remote build. Actually it's not reproducible, as local paths will be different on different machines.
+            # But we assume that conan works correctly here.
+            # IMPORTANT: Not compatible with bazel < 7.1
+            reproducible = True,
+        )
+
+    load_dependencies = module_extension(
+        implementation = _load_dependenies_impl,
+        os_dependent = True,
+        arch_dependent = True,
+    )
+
+Given the example above, a Bazel version above 7, and imagining that your Module.bazel is at the same directory, you would have to add these lines in there:
+
+.. code-block:: python
+    :caption: Module.bazel
+
+    load_conan_dependencies = use_extension("//:conan_deps_module_extension.bzl", "load_dependencies")
+    use_repo(load_conan_dependencies, "zlib")
+
 .. code-block:: python
     :caption: zlib/BUILD.bazel
 
@@ -160,6 +204,8 @@ Running again the :command:`conan install` command, we now get this structure:
     ├── conan
     │   ├── BUILD.bazel
     │   ├── dependencies.bzl
+    │   ├── conan_deps_module_extension.bzl
+    │   ├── conan_deps_repo_rules.bzl
     │   └── zlib
     │       └── BUILD.bazel
     └── conanfile.py
@@ -241,6 +287,8 @@ Running the :command:`conan install` command, the structure created is as follow
     │   ├── BUILD.bazel
     │   ├── build-my_tool
     │   │   └── BUILD.bazel
+    │   ├── conan_deps_module_extension.bzl
+    │   ├── conan_deps_repo_rules.bzl
     │   └── dependencies.bzl
     └── conanfile.py