build(revapi): Verify API/ABI compatibility during build (#246)

* build(revapi): Add palantir.revapi plugin to verify API/ABI compatibility between versions

* ci(revapi): Accept changes until v2 is released

* docs(licenses): Add Revapi license

* docs(CONTRIBUTING): Explain what revapi plugin does and how to accept changes

.github/workflows/gradle.yml

@@ -35,7 +35,11 @@ jobs:
 
     - name: Setup Gradle
       uses: gradle/[email protected]
-
+
+    # Temporary until release of v2
+    - name: Accept breaking changes
+      run: ./gradlew :revapiAcceptAllBreaks --justification 'Changes for v2'
+
     - name: Execute Gradle build
       run: ./gradlew build
 

.gitignore

@@ -16,3 +16,6 @@ target
 
 # MacOS
 .DS_Store
+
+# Palantir Revapi
+.palantir

CONTRIBUTING.md

@@ -43,6 +43,9 @@ To send us a pull request, please:
 4. Ensure unit tests cover your change and demonstrate expected behavior
 5. Ensure unit tests do NOT require AWS credentials or S3 connectivity by using Mocks for any `S3Client` or `S3AsyncClient`. Remember, unit tests test this library and not the functionality of S3.
 6. Run `./gradlew check` to ensure local tests pass and test coverage reports are produced.
+This will also check for API/ABI compatibility using the [rev-api gradle plugin](https://github.com/palantir/gradle-revapi/tree/develop).
+In case there is a justified breaking change, you can [accept](https://github.com/palantir/gradle-revapi/tree/develop#accepting-breaks) them.
+Please mention the change and reason when opening the PR, so that maintainers consider this when versioning.
 7. Ensure test coverage is not degraded. Reports can be found at `build/reports/jacoco/test/html/index.html`.
 8. Send us a pull request, answering any default questions in the pull request interface.
 9. Pay attention to any automated CI failures reported in the pull request, and stay involved in the conversation.

THIRD-PARTY

@@ -451,3 +451,209 @@ 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.
+
+** Gradle-Revapi -- https://github.com/palantir/gradle-revapi -- Apache-2.0 license
+
+
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build.gradle

@@ -14,6 +14,7 @@ plugins {
     id 'jacoco'
     id 'jvm-test-suite'
     id 'com.github.johnrengelman.shadow' version '7.1.2'
+    id 'com.palantir.revapi' version '1.7.0'
 }
 
 repositories {