5 The formatter and the linter

@@ -5,6 +5,7 @@ Cheese App API Service
 from fastapi import FastAPI
 from starlette.middleware.cors import CORSMiddleware
 import math
+import os
 from api.utils import power
 
 # Setup FastAPI app
@@ -19,13 +20,10 @@ app.add_middleware(
     allow_headers=["*"],
 )
 
-
 # Routes
 @app.get("/")
 async def get_index():
     return {"message": "Welcome to the Cheese App CI/CD Tutorial!"}
-
-
 @app.get("/health")
 async def health_check():
     return {"status": "healthy"}
@@ -36,6 +34,6 @@ async def calculate_euclidean_distance(x: float = 1, y: float = 2):
     """Calculate the Euclidean distance from origin: sqrt(x^2 + y^2)
     Returns the distance of a point (x, y) from the origin (0, 0)
     """
-    z = power(x, 2) + power(y, 2)
+    z=power(x,2)+power(y,2)
     result = math.sqrt(z)
-    return {"x": x, "y": y, "distance": result}
+    return {"x": x, "y": y, "distance": result, "message": "This is a very long line that exceeds 120 characters and Black will complain about it so we need to fix this formatting issue"}

@@ -4,6 +4,11 @@ Used by the Cheese App API Service
 """
 
 
-def power(base, exponent):
+def power(base,exponent):
     """Calculate base raised to the power of exponent"""
     return base**exponent
+
+
+
+def unused_function():
+    pass

@@ -16,6 +16,9 @@ package = false
 default-groups = "all"
 
 [dependency-groups]
+lint = [
+    "ruff>=0.17.1",
+]
 test = [
     "httpx2>=2.13.1",
     "pytest>=9.1.1",

@@ -30,3 +30,11 @@ test = [
 # The tests are in tests/, and import the package api from src/api-service/
 testpaths = ["tests"]
 pythonpath = ["src/api-service"]
+
+[tool.ruff]
+# The longest line, for the formatter and the linter
+line-length = 120
+
+[tool.ruff.lint]
+# The rules that flake8 checks: pycodestyle's errors (E) and warnings (W), and pyflakes (F)
+select = ["E", "W", "F"]

@@ -44,3 +44,11 @@ stop:
 # Run the tests, and show which lines of the package api they ran. Extra arguments go to pytest: just cov tests/unit
 cov *args:
     uv run pytest --cov=api --cov-report=term-missing "$@"
+
+# Format the code, one way. Extra arguments go to ruff: just fmt --check, just fmt --diff
+fmt *args:
+    uv run ruff format "$@"
+
+# Check the code against the rules in pyproject.toml. Extra arguments go to ruff: just lint --fix
+lint *args:
+    uv run ruff check "$@"

@@ -20,10 +20,13 @@ app.add_middleware(
     allow_headers=["*"],
 )
 
+
 # Routes
 @app.get("/")
 async def get_index():
     return {"message": "Welcome to the Cheese App CI/CD Tutorial!"}
+
+
 @app.get("/health")
 async def health_check():
     return {"status": "healthy"}
@@ -34,6 +37,11 @@ async def calculate_euclidean_distance(x: float = 1, y: float = 2):
     """Calculate the Euclidean distance from origin: sqrt(x^2 + y^2)
     Returns the distance of a point (x, y) from the origin (0, 0)
     """
-    z=power(x,2)+power(y,2)
+    z = power(x, 2) + power(y, 2)
     result = math.sqrt(z)
-    return {"x": x, "y": y, "distance": result, "message": "This is a very long line that exceeds 120 characters and Black will complain about it so we need to fix this formatting issue"}
+    return {
+        "x": x,
+        "y": y,
+        "distance": result,
+        "message": "This is a very long line that exceeds 120 characters and Black will complain about it so we need to fix this formatting issue",
+    }

@@ -4,11 +4,10 @@ Used by the Cheese App API Service
 """
 
 
-def power(base,exponent):
+def power(base, exponent):
     """Calculate base raised to the power of exponent"""
     return base**exponent
 
 
-
 def unused_function():
     pass

@@ -5,7 +5,6 @@ Cheese App API Service
 from fastapi import FastAPI
 from starlette.middleware.cors import CORSMiddleware
 import math
-import os
 from api.utils import power
 
 # Setup FastAPI app

@@ -42,5 +42,5 @@ async def calculate_euclidean_distance(x: float = 1, y: float = 2):
         "x": x,
         "y": y,
         "distance": result,
-        "message": "This is a very long line that exceeds 120 characters and Black will complain about it so we need to fix this formatting issue",
+        "message": "This is a very long line that exceeds 120 characters blah",
     }

@@ -52,3 +52,9 @@ fmt *args:
 # Check the code against the rules in pyproject.toml. Extra arguments go to ruff: just lint --fix
 lint *args:
     uv run ruff check "$@"
+
+# Everything a commit must pass: the format, the lint and the tests
+check:
+    just fmt --check
+    just lint
+    just test -q