[fastapi] Implement FAST001 (fastapi-redundant-response-model) and FAST002 (fastapi-non-annotated-dependency)

crates/ruff_linter/resources/test/fixtures/fastapi/FAST001.py

@@ -0,0 +1,110 @@
+from typing import List, Dict
+
+from fastapi import FastAPI, APIRouter
+from pydantic import BaseModel
+
+app = FastAPI()
+router = APIRouter()
+
+
+class Item(BaseModel):
+    name: str
+
+
+# Errors
+
+
+@app.post("/items/", response_model=Item)
+async def create_item(item: Item) -> Item:
+    return item
+
+
+@app.post("/items/", response_model=list[Item])
+async def create_item(item: Item) -> list[Item]:
+    return item
+
+
+@app.post("/items/", response_model=List[Item])
+async def create_item(item: Item) -> List[Item]:
+    return item
+
+
+@app.post("/items/", response_model=Dict[str, Item])
+async def create_item(item: Item) -> Dict[str, Item]:
+    return item
+
+
+@app.post("/items/", response_model=str)
+async def create_item(item: Item) -> str:
+    return item
+
+
+@app.get("/items/", response_model=Item)
+async def create_item(item: Item) -> Item:
+    return item
+
+
+@app.get("/items/", response_model=Item)
+@app.post("/items/", response_model=Item)
+async def create_item(item: Item) -> Item:
+    return item
+
+
+@router.get("/items/", response_model=Item)
+async def create_item(item: Item) -> Item:
+    return item
+
+
+# OK
+
+
+async def create_item(item: Item) -> Item:
+    return item
+
+
+@app("/items/", response_model=Item)
+async def create_item(item: Item) -> Item:
+    return item
+
+
+@cache
+async def create_item(item: Item) -> Item:
+    return item
+
+
+@app.post("/items/", response_model=str)
+async def create_item(item: Item) -> Item:
+    return item
+
+
+@app.post("/items/")
+async def create_item(item: Item) -> Item:
+    return item
+
+
+@app.post("/items/", response_model=str)
+async def create_item(item: Item):
+    return item
+
+
+@app.post("/items/", response_model=list[str])
+async def create_item(item: Item) -> Dict[str, Item]:
+    return item
+
+
+@app.post("/items/", response_model=list[str])
+async def create_item(item: Item) -> list[str, str]:
+    return item
+
+
+@app.post("/items/", response_model=Dict[str, int])
+async def create_item(item: Item) -> Dict[str, str]:
+    return item
+
+
+app = None
+
+
+@app.post("/items/", response_model=Item)
+async def create_item(item: Item) -> Item:
+    return item

crates/ruff_linter/resources/test/fixtures/fastapi/FAST002.py

@@ -0,0 +1,68 @@
+from fastapi import (
+    FastAPI,
+    APIRouter,
+    Query,
+    Path,
+    Body,
+    Cookie,
+    Header,
+    File,
+    Form,
+    Depends,
+    Security,
+)
+from pydantic import BaseModel
+
+app = FastAPI()
+router = APIRouter()
+
+
+# Errors
+
+@app.get("/items/")
+def get_items(
+    current_user: User = Depends(get_current_user),
+    some_security_param: str = Security(get_oauth2_user),
+):
+    pass
+
+
+@app.post("/stuff/")
+def do_stuff(
+    some_query_param: str | None = Query(default=None),
+    some_path_param: str = Path(),
+    some_body_param: str = Body("foo"),
+    some_cookie_param: str = Cookie(),
+    some_header_param: int = Header(default=5),
+    some_file_param: UploadFile = File(),
+    some_form_param: str = Form(),
+):
+    # do stuff
+    pass
+
+
+# Unchanged
+
+
+@app.post("/stuff/")
+def do_stuff(
+    no_default: Body("foo"),
+    no_type_annotation=str,
+    no_fastapi_default: str = BaseModel(),
+):
+    pass
+
+
+# OK
+
+@app.post("/stuff/")
+def do_stuff(
+    some_path_param: Annotated[str, Path()],
+    some_cookie_param: Annotated[str, Cookie()],
+    some_file_param: Annotated[UploadFile, File()],
+    some_form_param: Annotated[str, Form()],
+    some_query_param: Annotated[str | None, Query()] = None,
+    some_body_param: Annotated[str, Body()] = "foo",
+    some_header_param: Annotated[int, Header()] = 5,
+):
+    pass

crates/ruff_linter/src/checkers/ast/analyze/statement.rs

@@ -8,11 +8,11 @@ use ruff_text_size::Ranged;
 use crate::checkers::ast::Checker;
 use crate::registry::Rule;
 use crate::rules::{
-    airflow, flake8_async, flake8_bandit, flake8_boolean_trap, flake8_bugbear, flake8_builtins,
-    flake8_debugger, flake8_django, flake8_errmsg, flake8_import_conventions, flake8_pie,
-    flake8_pyi, flake8_pytest_style, flake8_raise, flake8_return, flake8_simplify, flake8_slots,
-    flake8_tidy_imports, flake8_type_checking, mccabe, pandas_vet, pep8_naming, perflint,
-    pycodestyle, pyflakes, pygrep_hooks, pylint, pyupgrade, refurb, ruff, tryceratops,
+    airflow, fastapi, flake8_async, flake8_bandit, flake8_boolean_trap, flake8_bugbear,
+    flake8_builtins, flake8_debugger, flake8_django, flake8_errmsg, flake8_import_conventions,
+    flake8_pie, flake8_pyi, flake8_pytest_style, flake8_raise, flake8_return, flake8_simplify,
+    flake8_slots, flake8_tidy_imports, flake8_type_checking, mccabe, pandas_vet, pep8_naming,
+    perflint, pycodestyle, pyflakes, pygrep_hooks, pylint, pyupgrade, refurb, ruff, tryceratops,
 };
 use crate::settings::types::PythonVersion;
 
@@ -88,6 +88,12 @@ pub(crate) fn statement(stmt: &Stmt, checker: &mut Checker) {
             if checker.enabled(Rule::DjangoNonLeadingReceiverDecorator) {
                 flake8_django::rules::non_leading_receiver_decorator(checker, decorator_list);
             }
+            if checker.enabled(Rule::FastApiRedundantResponseModel) {
+                fastapi::rules::fastapi_redundant_response_model(checker, function_def);
+            }
+            if checker.enabled(Rule::FastApiNonAnnotatedDependency) {
+                fastapi::rules::fastapi_non_annotated_dependency(checker, function_def);
+            }
             if checker.enabled(Rule::AmbiguousFunctionName) {
                 if let Some(diagnostic) = pycodestyle::rules::ambiguous_function_name(name) {
                     checker.diagnostics.push(diagnostic);

crates/ruff_linter/src/codes.rs

@@ -912,6 +912,10 @@ pub fn code_to_rule(linter: Linter, code: &str) -> Option<(RuleGroup, Rule)> {
         (Numpy, "003") => (RuleGroup::Stable, rules::numpy::rules::NumpyDeprecatedFunction),
         (Numpy, "201") => (RuleGroup::Stable, rules::numpy::rules::Numpy2Deprecation),
 
+        // fastapi
+        (FastApi, "001") => (RuleGroup::Preview, rules::fastapi::rules::FastApiRedundantResponseModel),
+        (FastApi, "002") => (RuleGroup::Preview, rules::fastapi::rules::FastApiNonAnnotatedDependency),
+
         // pydoclint
         (Pydoclint, "501") => (RuleGroup::Preview, rules::pydoclint::rules::DocstringMissingException),
         (Pydoclint, "502") => (RuleGroup::Preview, rules::pydoclint::rules::DocstringExtraneousException),
@@ -947,6 +951,7 @@ pub fn code_to_rule(linter: Linter, code: &str) -> Option<(RuleGroup, Rule)> {
         (Ruff, "030") => (RuleGroup::Preview, rules::ruff::rules::AssertWithPrintMessage),
         (Ruff, "100") => (RuleGroup::Stable, rules::ruff::rules::UnusedNOQA),
         (Ruff, "101") => (RuleGroup::Preview, rules::ruff::rules::RedirectedNOQA),
+
         (Ruff, "200") => (RuleGroup::Stable, rules::ruff::rules::InvalidPyprojectToml),
         #[cfg(any(feature = "test-rules", test))]
         (Ruff, "900") => (RuleGroup::Stable, rules::ruff::rules::StableTestRule),

crates/ruff_linter/src/registry.rs

@@ -193,6 +193,9 @@ pub enum Linter {
     /// NumPy-specific rules
     #[prefix = "NPY"]
     Numpy,
+    /// [FastAPI](https://pypi.org/project/fastapi/)
+    #[prefix = "FAST"]
+    FastApi,
     /// [Airflow](https://pypi.org/project/apache-airflow/)
     #[prefix = "AIR"]
     Airflow,

crates/ruff_linter/src/rules/fastapi/mod.rs

@@ -0,0 +1,27 @@
+//! FastAPI-specific rules.
+pub(crate) mod rules;
+
+#[cfg(test)]
+mod tests {
+    use std::convert::AsRef;
+    use std::path::Path;
+
+    use anyhow::Result;
+    use test_case::test_case;
+
+    use crate::registry::Rule;
+    use crate::test::test_path;
+    use crate::{assert_messages, settings};
+
+    #[test_case(Rule::FastApiRedundantResponseModel, Path::new("FAST001.py"))]
+    #[test_case(Rule::FastApiNonAnnotatedDependency, Path::new("FAST002.py"))]
+    fn rules(rule_code: Rule, path: &Path) -> Result<()> {
+        let snapshot = format!("{}_{}", rule_code.as_ref(), path.to_string_lossy());
+        let diagnostics = test_path(
+            Path::new("fastapi").join(path).as_path(),
+            &settings::LinterSettings::for_rule(rule_code),
+        )?;
+        assert_messages!(snapshot, diagnostics);
+        Ok(())
+    }
+}