dash: Add README.md and move target to docs directory

The README.md provides better insignt how Bazel and Dash
(EF License checker) communicate and work in chain. Also the
target for checking Python licenses is moved to docs directory.

BUILD

@@ -12,7 +12,6 @@
 # *******************************************************************************
 
 load("//tools/cr_checker:cr_checker.bzl", "copyright_checker")
-load("//tools/dash:dash.bzl", "dash_license_checker")
 
 test_suite(
     name = "format.check",
@@ -36,12 +35,6 @@ copyright_checker(
     visibility = ["//visibility:public"],
 )
 
-dash_license_checker(
-    name = "python",
-    src = "//docs:requirements_lock",
-    visibility = ["//visibility:public"],
-)
-
 exports_files([
     "MODULE.bazel",
     "BUILD",

docs/BUILD

@@ -43,6 +43,7 @@ load("@rules_pkg//pkg:mappings.bzl", "pkg_files")
 load("@rules_pkg//pkg:tar.bzl", "pkg_tar")
 load("@rules_python//python:pip.bzl", "compile_pip_requirements")
 load("@rules_python//sphinxdocs:sphinx.bzl", "sphinx_build_binary", "sphinx_docs")
+load("//tools/dash:dash.bzl", "dash_license_checker")
 load("//tools/testing/pytest:defs.bzl", "score_py_pytest")
 
 sphinx_requirements = all_requirements + [
@@ -188,3 +189,9 @@ filegroup(
     ],
     visibility = ["//visibility:public"],
 )
+
+dash_license_checker(
+    name = "python",
+    src = "//docs:requirements_lock",
+    visibility = ["//visibility:public"],
+)

tools/dash/README.md

@@ -0,0 +1,61 @@
+# DASH License Checker Bazel Integration
+
+This directory provides Bazel build configurations and custom rules to integrate the DASH license checker into projects. The setup includes a macro to define a java_binary target for license validation and a custom rule for converting requirement files into the appropriate DASH format.
+
+## Directory Structure
+
+```bash
+├── BUILD
+├── dash.bzl
+├── formatters
+│   ├── BUILD
+│   ├── dash_format_converter.bzl
+│   └── dash_format_converter.py
+└── README.md
+```
+
+### File Descriptions
+
+**BUILD**
+
+- This file is empty and serves only to mark this directory as a Bazel package.
+
+**dash.bzl**
+
+- Contains the dash_license_checker macro, which defines a `java_binary` target to run the DASH license checker.
+- Loads `dash_format_converter.bzl` from the `formatters` package to preprocess requirement files.
+- Converts the input `requirements_lock.txt` file into a format compatible with the DASH license tool before invoking the Java-based checker.
+
+**formatters/BUILD**
+
+- Empty file indicating that formatters is a Bazel package.
+
+**formatters/dash_format_converter.bzl**
+
+- Defines a custom Bazel rule `dash_format_converter`.
+- Calls `dash_format_converter.py` to transform `requirements_lock.txt` into a format that the DASH tool can process.
+
+**formatters/dash_format_converter.py**
+
+- Implements the logic to convert `requirements_lock.`txt into a format accepted by the DASH license checker.
+- This script is executed as part of the `dash_format_converter` Bazel rule.
+
+## Usage
+
+To integrate the DASH license checker into your Bazel project, define a target in your `BUILD` file as follows:
+
+```bash
+load("//tools/dash:dash.bzl", "dash_license_checker")
+
+dash_license_checker(
+    name = "my_project_license_check",
+    src = "//path/to/requirements_lock.txt",
+    visibility = ["//visibility:public"],
+)
+```
+
+This will:
+
+1. Use dash_format_converter to process requirements_lock.txt.
+2. Create a java_binary target that executes the DASH license checker with the converted file.
+3. Ensure compliance with dependency licensing requirements in your project.

tools/dash/dash.bzl

@@ -37,7 +37,7 @@ def dash_license_checker(
     validation across projects.
     """
     dash_format_converter(
-        name = "formatted_deps",
+        name = "{}2dash".format(name),
         requirement_file = src,
     )
 
@@ -47,9 +47,9 @@ def dash_license_checker(
         runtime_deps = [
             "@dash_license_tool//jar",
         ],
-        args = ["$(location :formatted_deps)"],
+        args = ["$(location :{}2dash)".format(name)],
         data = [
-            ":formatted_deps",
+            ":{}2dash".format(name),
         ],
         visibility = ["//visibility:public"],
     )