chore: add license check using apache rat (#14)

* chore: add license check using apache rat

* chore: update README

Author: lucasfang

.github/.licenserc.yaml

@@ -0,0 +1,14 @@
+build/*
+build-debug/*
+build-release/*
+test_data/*
+third_party/*
+build_support/*
+scripts/*
+cmake_modules/*
+.codespell_ignore
+.gitignore
+rat-report.txt
+requirements.txt
+.gitattributes
+.*\.svg$

.github/.rat-excludes

@@ -0,0 +1,53 @@
+# Copyright 2025-present Alibaba Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+name: License Check
+
+on:
+  pull_request:
+  push:
+    branches:
+      - main
+
+jobs:
+  rat-check:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Set up Java
+        uses: actions/setup-java@v4
+        with:
+          distribution: 'temurin'
+          java-version: '17'
+
+      - name: Download Apache Rat jar
+        run: |
+          wget https://repo1.maven.org/maven2/org/apache/rat/apache-rat/0.16.1/apache-rat-0.16.1.jar -O rat.jar
+
+      - name: Run Apache Rat
+        run: |
+          java -jar rat.jar -E .github/.rat-excludes -d . > rat-report.txt
+      - name: Check for Unapproved Licenses
+        run: |
+          if grep "Files with unapproved licenses" rat-report.txt; then
+            echo "❌ Found files with unapproved licenses!"
+            cat rat-report.txt
+            exit 1
+          else
+            echo "✅ All files have approved licenses."
+            cat rat-report.txt
+          fi

.github/workflows/license_check.yaml

@@ -30,7 +30,7 @@ Paimon C++ is a high-performance C++ implementation of [Apache Paimon](https://p
 * Memory pool interfaces and a default implementation.
 * Thread pool executor interfaces and a default implementation.
 * Compatible with Java Paimon format and communication protocol (e.g., commit message, data splits, manifests).
-* Only support x86 platform.
+* Note: The current implementation only supports the x86_64 architecture.
 
 ## Write And Commit Example
 
@@ -127,6 +127,16 @@ $ cd build
 $ cmake ..
 $ make
 ```
+## Contributing
+
+Paimon-cpp is an active open-source project and we welcome people who want to contribute or share good ideas!
+Before contributing, you are encouraged to check out our [documentation](https://alibaba.github.io/paimon-cpp/).
+
+If you have suggestions, feedback, want to report a bug or request a feature, please open an [issue](https://github.com/alibaba/paimon-cpp/issues/new).
+Pull requests are also very welcome!
+
+We value respectful and open collaboration, and appreciate everyone who helps make paimon-cpp better. Thank you for your support!
+
 ### Linting
 
 Install the python package `pre-commit` and run once `pre-commit install`.