[eclipse-iceoryx#460] Add 'dev_permissions' feature flag to bazel

.bazelrc

@@ -6,3 +6,11 @@ build:windows --cxxopt="/std:c++17"
 build:mingw --cxxopt="-std=c++17"
 
 build --action_env=CARGO_BAZEL_REPIN=true
+
+#
+# feature flags
+#
+
+# value [auto, on, off]
+# 'auto' is defined by the crate owner ('off' for this feature) and the default value if the flag is not set
+#build --//:feature_dev_permissions=on

BUILD.bazel

@@ -37,6 +37,12 @@ config_setting(
     flag_values = {"@bazel_tools//tools/cpp:compiler": "msvc-cl"},
 )
 
+alias(
+    name = "feature_dev_permissions",
+    actual = "//iceoryx2-cal:feature_dev_permissions",
+    visibility = ["//visibility:public"],
+)
+
 alias(
     name = "iceoryx2",
     actual = "//iceoryx2:iceoryx2",

WORKSPACE.bazel

@@ -114,6 +114,23 @@ load("@crate_index//:defs.bzl", "crate_repositories")
 
 crate_repositories()
 
+BAZEL_SKYLIB_VERSION = "1.7.1"
+
+# Load skylib for custom build config
+maybe(
+    name = "bazel_skylib",
+    repo_rule = http_archive,
+    sha256 = "bc283cdfcd526a52c3201279cda4bc298652efa898b10b4db0837dc51652756f",
+    urls = [
+        "https://mirror.bazel.build/github.com/bazelbuild/bazel-skylib/releases/download/{version}/bazel-skylib-{version}.tar.gz".format(version = BAZEL_SKYLIB_VERSION),
+        "https://github.com/bazelbuild/bazel-skylib/releases/download/{version}/bazel-skylib-{version}.tar.gz".format(version = BAZEL_SKYLIB_VERSION),
+    ],
+)
+
+load("@bazel_skylib//:workspace.bzl", "bazel_skylib_workspace")
+
+bazel_skylib_workspace()
+
 
 # Load iceoryx rules
 ICEORYX_VERSION = "2.95.2"

doc/bazel/README.md

@@ -124,10 +124,10 @@ or
 CARGO_BAZEL_REPIN=1 bazel build //...
 ```
 
-Alternatively, this can also be achieved by adding the following
-line to the `.bazelrc` file:
+To make syncing dependencies automatic for every build, add the
+following line to your `.bazelrc` file:
 
-```
+```bazel
 build --action_env=CARGO_BAZEL_REPIN=true
 ```
 
@@ -159,6 +159,49 @@ cc_binary(
 * **For C++**: Use `@iceoryx2//:iceoryx2-cxx-static` or
   `@iceoryx2//:iceoryx2-cxx-shared`
 
+### Feature Flags
+
+iceoryx2 provides several feature flags that can be configured using bazel
+build options. These flags allow you to enable or disable specific features
+when building the project.
+
+#### Enabling a Feature Flag via Command Line
+
+To set a feature flag directly from the command line during the build, use the
+following format:
+
+```bash
+bazel build --@iceoryx2//:<feature_flag> //...
+```
+
+For example, to enable a feature flag called `foo`, you would run:
+
+```bash
+bazel build --@iceoryx2//:foo //...
+```
+
+#### Setting Feature Flags in .bazelrc
+
+You can also persist feature flag configurations by specifying them in the
+`.bazelrc` file. This method is useful for keeping your build settings
+consistent across different environments.
+
+```bazel
+build --@iceoryx2//:<feature_flag>=on
+```
+
+For instance, to enable the `foo` feature by default in `.bazelrc`, you would add:
+
+```bazel
+build --@iceoryx2//:foo=on
+```
+
+#### List of Available Features
+
+| Feature Flag            | Valid Values                 | Crate Default      |
+| ----------------------- | ---------------------------- | ------------------ |
+| dev_permissions         | auto, on, off                | auto == off        |
+
 ## Instructions for iceoryx2 Developers
 
 When working with Bazel and Cargo in this project, ensure the following steps are

iceoryx2-cal/BUILD.bazel

@@ -12,16 +12,53 @@
 
 package(default_visibility = ["//visibility:public"])
 
+load("@bazel_skylib//lib:selects.bzl", "selects")
+load("@bazel_skylib//rules:common_settings.bzl", "string_flag")
 load("@rules_rust//rust:defs.bzl", "rust_library")
 
 filegroup(
     name = "all_srcs",
     srcs = glob(["**"]),
 )
 
+string_flag(
+    name = "feature_dev_permissions",
+    build_setting_default = "auto",
+    visibility = ["//visibility:public"],
+)
+
+config_setting(
+    name = "dev_permissions_auto",
+    flag_values = {
+        ":feature_dev_permissions": "auto",
+    },
+)
+
+config_setting(
+    name = "dev_permissions_enabled",
+    flag_values = {
+        ":feature_dev_permissions": "on",
+    },
+)
+
+# NOTE: while this seems superfluous, it is the pattern for cases where *_auto is on by default;
+#       therefore this target is introduced to keep all feature flags consistent
+selects.config_setting_group(
+    name = "cfg_feature_dev_permissions",
+    match_any = [
+        ":dev_permissions_enabled",
+    ],
+)
+
 rust_library(
     name = "iceoryx2-cal",
     srcs = glob(["src/**/*.rs"]),
+    crate_features = select({
+        "cfg_feature_dev_permissions": [
+            "dev_permissions"
+        ],
+        "//conditions:default": [],
+    }),
     deps = [
         "//iceoryx2-bb/container:iceoryx2-bb-container",
         "//iceoryx2-bb/elementary:iceoryx2-bb-elementary",