feat(lab03): add coverage threshold and improve CI

- Add pyproject.toml with 70% coverage threshold
- Configure pytest-cov fail-under for CI enforcement
- Add codecov upload for Go workflow
- Update LAB03.md with new coverage stats (98%)
- Simplify pytest command to use pyproject.toml config

Coverage improvements:
- Python: 98% coverage with 70% threshold
- Go: 67.2% coverage with codecov integration

Author: pepega

.github/workflows/go-ci.yml

@@ -103,6 +103,15 @@ jobs:
       - name: 📊 Display coverage
         run: go tool cover -func=coverage.out
 
+      - name: 📤 Upload coverage to Codecov
+        uses: codecov/codecov-action@v4
+        with:
+          file: app_go/coverage.out
+          flags: go-unittests
+          name: codecov-go
+          fail_ci_if_error: false
+          token: ${{ secrets.CODECOV_TOKEN }}
+
   # ==========================================================================
   # Job 3: Security Scanning with Snyk
   # ==========================================================================

.github/workflows/python-ci.yml

@@ -69,7 +69,7 @@ jobs:
         run: python -m ruff check .
 
       - name: Run unit tests with coverage
-        run: python -m pytest -v --cov=app --cov-report=xml --cov-report=term tests/
+        run: python -m pytest tests/
 
       - name: Upload coverage to Codecov
         uses: codecov/codecov-action@v4

app_python/docs/LAB03.md

@@ -138,9 +138,11 @@ push/PR → lint-test (3.11) ─┬─→ docker-build-push → Docker Hub
 ### Test Coverage Integration
 
 - **Tool:** pytest-cov + codecov.io
-- **Current Coverage:** 80% (41/51 lines)
+- **Current Coverage:** 98% (40/41 lines)
+- **Threshold:** 70% minimum (configured in `pyproject.toml`)
 - **Upload:** Automated to codecov.io on each push
 - **Badge:** Added to app_python/README.md
+- **Fail on low coverage:** CI fails if coverage drops below 70%
 
 ---
 
@@ -149,7 +151,7 @@ push/PR → lint-test (3.11) ─┬─→ docker-build-push → Docker Hub
 ### Local Tests with Coverage
 
 ```
-$ python -m pytest --cov=app --cov-report=term tests/
+$ python -m pytest tests/
 ========================== test session starts ==========================
 collected 15 items
 
@@ -160,20 +162,21 @@ ___________ coverage: platform darwin, python 3.14.0-final-0 ____________
 
 Name     Stmts   Miss  Cover
 ----------------------------
-app.py      51     10    80%
+app.py      41      1    98%
 ----------------------------
-TOTAL       51     10    80%
+TOTAL       41      1    98%
 
-========================== 15 passed in 0.08s ===========================
+Required test coverage of 70% reached. Total coverage: 97.56%
+========================== 15 passed in 0.10s ===========================
 ```
 
 **Coverage Analysis:**
-- **Overall Coverage:** 80%
-- **Lines Tested:** 41 out of 51 lines
+- **Overall Coverage:** 98%
+- **Lines Tested:** 40 out of 41 lines
+- **Coverage Threshold:** 70% (CI fails if below)
 - **What's Covered:** All HTTP endpoints, helper functions, error handlers
 - **What's NOT Covered:** 
-  - `if __name__ == '__main__'` block (entry point, not testable without subprocess)
-  - Some edge case handling (not critical for this service)
+  - `if __name__ == '__main__'` block (entry point, excluded in pyproject.toml)
 
 ### Local Lint
 

app_python/pyproject.toml

@@ -0,0 +1,26 @@
+[tool.pytest.ini_options]
+testpaths = ["tests"]
+python_files = ["test_*.py"]
+python_classes = ["Test*"]
+python_functions = ["test_*"]
+addopts = "-v --cov=app --cov-report=term --cov-report=xml --cov-fail-under=70"
+
+[tool.coverage.run]
+source = ["."]
+omit = ["tests/*", "venv/*", ".venv/*", "__pycache__/*"]
+
+[tool.coverage.report]
+exclude_lines = [
+    "pragma: no cover",
+    "if __name__ == .__main__.:",
+    "raise NotImplementedError",
+]
+fail_under = 70
+
+[tool.ruff]
+line-length = 100
+target-version = "py311"
+
+[tool.ruff.lint]
+select = ["E", "F", "W", "I", "N", "UP", "B", "C4"]
+ignore = ["E501"]