ci: Add GH Action to detect compatibility breaking chages (#2877)

Author: aahung

.github/workflows/check_interface_compatibility.yml

@@ -0,0 +1,83 @@
+name: Check interface compatibility
+
+on:
+  pull_request_target:
+
+permissions:
+  pull-requests: write
+
+jobs:
+  check-interface-compatibility:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout the base branch
+        uses: actions/checkout@v3
+
+      - uses: actions/setup-python@v4
+        with:
+          python-version: "3.10"
+
+      - name: Extract original public interfaces
+        run: |
+          make init
+          bin/public_interface.py extract > ${{ runner.temp }}/interfaces.original.json
+
+      - name: Backup original bin/public_interface.py
+        run: |
+          # Keep a copy of bin/public_interface.py to use on the base branch
+          # So we are using the same bin/public_interface.py to process old/new codebase.
+          # Because the step has credential of GitHub token to post comments,
+          # always use the original version that is in our repository.
+          cp bin/public_interface.py ${{ runner.temp }}/public_interface.py
+
+      - name: Checkout the PR
+        uses: actions/checkout@v3
+        with:
+          ref: "refs/pull/${{ github.event.number }}/merge"
+
+      - name: Extract PR public interfaces
+        run: |
+          make init
+          # Recover bin/public_interface.py
+          cp ${{ runner.temp }}/public_interface.py bin/public_interface.py
+          bin/public_interface.py extract > ${{ runner.temp }}/interfaces.new.json
+    
+      - name: Detect compatibility breaking changes
+        id: detect
+        run: |
+          exit_code=0
+          output=$(bin/public_interface.py check ${{ runner.temp }}/interfaces.original.json ${{ runner.temp }}/interfaces.new.json) || exit_code=$?
+
+          # Show the output in job summary
+          echo "$output" >> $GITHUB_STEP_SUMMARY
+
+          # Update steps.detect.outputs.change_detected=true for next steps
+          if [ "$exit_code" -ne 0 ]; then
+            echo "change_detected=true" >> $GITHUB_OUTPUT
+          fi
+
+          # Save the output for next step to process it,
+          # and saving it into a file can avoid the need of escaping in github-script.
+          echo "$output" > ${{ runner.temp }}/output.md
+
+      - name: Post GitHub PR comment
+        if: ${{ steps.detect.outputs.change_detected }}
+        uses: actions/github-script@v6
+        with:
+          github-token: ${{secrets.GITHUB_TOKEN}}
+          script: |
+            const fs = require('fs');
+            const output = fs.readFileSync('${{ runner.temp }}/output.md', 'utf8')
+            github.rest.issues.createComment({
+              issue_number: context.issue.number,
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              body: output
+            })
+
+      - name: Show detection output
+        if: ${{ steps.detect.outputs.change_detected }}
+        run: |
+          cat ${{ runner.temp }}/output.md
+          exit 1

bin/public_interface.py

@@ -90,17 +90,16 @@ def _scan_methods_in_class(self, class_name: str, _class: Any) -> None:
 def _print(signature: Dict[str, inspect.Signature], variables: Set[str]) -> None:
     result: Dict[str, Any] = {"routines": {}, "variables": sorted(variables)}
     for key, value in signature.items():
-        for parameter in value.parameters.values():
-            result["routines"][key] = [
-                {
-                    "name": parameter.name,
-                    "kind": parameter.kind.name,
-                    "default": parameter.default,
-                }
-                if parameter.default != inspect.Parameter.empty
-                else {"name": parameter.name, "kind": parameter.kind.name}
-                for parameter in value.parameters.values()
-            ]
+        result["routines"][key] = [
+            {
+                "name": parameter.name,
+                "kind": parameter.kind.name,
+                "default": parameter.default,
+            }
+            if parameter.default != inspect.Parameter.empty
+            else {"name": parameter.name, "kind": parameter.kind.name}
+            for parameter in value.parameters.values()
+        ]
     print(json.dumps(result, indent=2, sort_keys=True))
 
 
@@ -132,12 +131,12 @@ def print_markdown(
             print("\n## Deleted module level variables")
             for name in self.deleted_variables:
                 print(f"- {name}")
-        if self.deleted_variables:
+        if self.deleted_routines:
             print("\n## Deleted routines")
             for name in self.deleted_routines:
                 print(f"- {name}")
         if self.incompatible_routines:
-            print("\n## Deleted routines")
+            print("\n## Incompatible routines")
             for name in self.incompatible_routines:
                 before = f"({', '.join(self._argument_to_str(arg) for arg in original_routines[name])})"
                 after = f"({', '.join(self._argument_to_str(arg) for arg in routines[name])})"