From f3f2cbbcdd1517464bd3e2714ccd1bc9f8edc928 Mon Sep 17 00:00:00 2001
From: AMBase <milnikovalexei@gmail.com>
Date: Mon, 13 Jan 2025 01:59:26 +0300
Subject: [PATCH 1/2] fix: parameter models with alias

---
 fastapi/dependencies/utils.py |  2 +-
 tests/test_param_models.py    | 71 +++++++++++++++++++++++++++++++++++
 2 files changed, 72 insertions(+), 1 deletion(-)
 create mode 100644 tests/test_param_models.py

diff --git a/fastapi/dependencies/utils.py b/fastapi/dependencies/utils.py
index e2866b488..4558d6224 100644
--- a/fastapi/dependencies/utils.py
+++ b/fastapi/dependencies/utils.py
@@ -772,7 +772,7 @@ def request_params_to_args(
                 )
         value = _get_multidict_value(field, received_params, alias=alias)
         if value is not None:
-            params_to_process[field.name] = value
+            params_to_process[field.alias] = value
         processed_keys.add(alias or field.alias)
         processed_keys.add(field.name)
 
diff --git a/tests/test_param_models.py b/tests/test_param_models.py
new file mode 100644
index 000000000..cecaa2793
--- /dev/null
+++ b/tests/test_param_models.py
@@ -0,0 +1,71 @@
+from fastapi import FastAPI
+from fastapi.params import Body, Cookie, Form, Header, Query
+from fastapi.testclient import TestClient
+from pydantic import BaseModel, Field
+from typing_extensions import Annotated
+
+app = FastAPI()
+
+
+class DataModel(BaseModel):
+    alias_with: str = Field(alias="with", default="nothing")
+
+
+@app.post("/param/body")
+def post_param_body(data: Annotated[DataModel, Body()]):
+    return data
+
+
+@app.post("/param/form")
+def post_param_form(data: Annotated[DataModel, Form()]):
+    return data
+
+
+@app.post("/param/query")
+def post_param_query(data: Annotated[DataModel, Query()]):
+    return data
+
+
+@app.post("/param/cookies")
+def post_param_cookies(data: Annotated[DataModel, Cookie()]):
+    return data
+
+
+@app.post("/param/headers")
+def post_param_headers(data: Annotated[DataModel, Header()]):
+    return data
+
+
+client = TestClient(app)
+
+
+def test_param_body_with_alias():
+    response = client.post("/param/body", json={"with": "something"})
+    assert response.status_code == 200, response.text
+    assert response.json() == {"with": "something"}
+
+
+def test_param_form_with_alias():
+    response = client.post("/param/form", data={"with": "something"})
+    assert response.status_code == 200, response.text
+    assert response.json() == {"with": "something"}
+
+
+def test_param_query_with_alias():
+    response = client.post("/param/query", params={"with": "something"})
+    assert response.status_code == 200, response.text
+    assert response.json() == {"with": "something"}
+
+
+def test_param_headers_with_alias():
+    response = client.post("/param/headers", headers={"with": "something"})
+    assert response.status_code == 200, response.text
+    assert response.json() == {"with": "something"}
+
+
+def test_param_cookies_with_alias():
+    with client as c:
+        c.cookies.set("with", "something")
+        response = c.post("/param/cookies")
+    assert response.status_code == 200, response.text
+    assert response.json() == {"with": "something"}

From c3cd5d3023b87b0651f2a35b0d7daea5f7e54980 Mon Sep 17 00:00:00 2001
From: AMBase <milnikovalexei@gmail.com>
Date: Sun, 26 Jan 2025 03:25:49 +0300
Subject: [PATCH 2/2] test: add check params_to_process dict in
 request_params_to_args function

---
 tests/test_param_models.py | 28 +++++++++++++++++-----------
 1 file changed, 17 insertions(+), 11 deletions(-)

diff --git a/tests/test_param_models.py b/tests/test_param_models.py
index cecaa2793..283de452d 100644
--- a/tests/test_param_models.py
+++ b/tests/test_param_models.py
@@ -8,7 +8,8 @@ app = FastAPI()
 
 
 class DataModel(BaseModel):
-    alias_with: str = Field(alias="with", default="nothing")
+    foo: str = Field(alias="bar", default="default_foo")
+    bar: str = Field(alias="foo", default="default_bar")
 
 
 @app.post("/param/body")
@@ -38,34 +39,39 @@ def post_param_headers(data: Annotated[DataModel, Header()]):
 
 client = TestClient(app)
 
+expected_json = {
+    "bar": "default_foo",
+    "foo": "set_foo",
+}
+
 
 def test_param_body_with_alias():
-    response = client.post("/param/body", json={"with": "something"})
+    response = client.post("/param/body", json={"foo": "set_foo"})
     assert response.status_code == 200, response.text
-    assert response.json() == {"with": "something"}
+    assert response.json() == expected_json
 
 
 def test_param_form_with_alias():
-    response = client.post("/param/form", data={"with": "something"})
+    response = client.post("/param/form", data={"foo": "set_foo"})
     assert response.status_code == 200, response.text
-    assert response.json() == {"with": "something"}
+    assert response.json() == expected_json
 
 
 def test_param_query_with_alias():
-    response = client.post("/param/query", params={"with": "something"})
+    response = client.post("/param/query", params={"foo": "set_foo"})
     assert response.status_code == 200, response.text
-    assert response.json() == {"with": "something"}
+    assert response.json() == expected_json
 
 
 def test_param_headers_with_alias():
-    response = client.post("/param/headers", headers={"with": "something"})
+    response = client.post("/param/headers", headers={"foo": "set_foo"})
     assert response.status_code == 200, response.text
-    assert response.json() == {"with": "something"}
+    assert response.json() == expected_json
 
 
 def test_param_cookies_with_alias():
     with client as c:
-        c.cookies.set("with", "something")
+        c.cookies.set("foo", "set_foo")
         response = c.post("/param/cookies")
     assert response.status_code == 200, response.text
-    assert response.json() == {"with": "something"}
+    assert response.json() == expected_json