Merge branch 'tiangolo:master' into Update-Chinese-translation-for-do…

…cs-zh-docs-tutorial-request-files.md

.github/workflows/build-docs.yml

@@ -22,15 +22,15 @@ jobs:
         id: cache
         with:
           path: ${{ env.pythonLocation }}
-          key: ${{ runner.os }}-python-${{ env.pythonLocation }}-${{ hashFiles('pyproject.toml') }}-docs-v2
+          key: ${{ runner.os }}-python-docs-${{ env.pythonLocation }}-${{ hashFiles('pyproject.toml') }}-v03
       - name: Install Flit
         if: steps.cache.outputs.cache-hit != 'true'
         run: python3.7 -m pip install flit
       - name: Install docs extras
         if: steps.cache.outputs.cache-hit != 'true'
         run: python3.7 -m flit install --deps production --extras doc
       - name: Install Material for MkDocs Insiders
-        if: github.event_name == 'pull_request' && github.event.pull_request.head.repo.fork == false && steps.cache.outputs.cache-hit != 'true'
+        if: ( github.event_name != 'pull_request' || github.event.pull_request.head.repo.fork == false ) && steps.cache.outputs.cache-hit != 'true'
         run: pip install git+https://${{ secrets.ACTIONS_TOKEN }}@github.com/squidfunk/mkdocs-material-insiders.git
       - name: Build Docs
         run: python3.7 ./scripts/docs.py build-all

.pre-commit-config.yaml

@@ -46,3 +46,6 @@ repos:
     rev: 22.3.0
     hooks:
     -   id: black
+ci:
+    autofix_commit_msg: 🎨 [pre-commit.ci] Auto format from pre-commit.com hooks
+    autoupdate_commit_msg: ⬆ [pre-commit.ci] pre-commit autoupdate

README.md

@@ -151,7 +151,7 @@ $ pip install "uvicorn[standard]"
 * Create a file `main.py` with:
 
 ```Python
-from typing import Optional
+from typing import Union
 
 from fastapi import FastAPI
 
@@ -164,7 +164,7 @@ def read_root():
 
 
 @app.get("/items/{item_id}")
-def read_item(item_id: int, q: Optional[str] = None):
+def read_item(item_id: int, q: Union[str, None] = None):
     return {"item_id": item_id, "q": q}
 ```
 
@@ -174,7 +174,7 @@ def read_item(item_id: int, q: Optional[str] = None):
 If your code uses `async` / `await`, use `async def`:
 
 ```Python hl_lines="9  14"
-from typing import Optional
+from typing import Union
 
 from fastapi import FastAPI
 
@@ -187,7 +187,7 @@ async def read_root():
 
 
 @app.get("/items/{item_id}")
-async def read_item(item_id: int, q: Optional[str] = None):
+async def read_item(item_id: int, q: Union[str, None] = None):
     return {"item_id": item_id, "q": q}
 ```
 
@@ -266,7 +266,7 @@ Now modify the file `main.py` to receive a body from a `PUT` request.
 Declare the body using standard Python types, thanks to Pydantic.
 
 ```Python hl_lines="4  9-12  25-27"
-from typing import Optional
+from typing import Union
 
 from fastapi import FastAPI
 from pydantic import BaseModel
@@ -277,7 +277,7 @@ app = FastAPI()
 class Item(BaseModel):
     name: str
     price: float
-    is_offer: Optional[bool] = None
+    is_offer: Union[bool, None] = None
 
 
 @app.get("/")
@@ -286,7 +286,7 @@ def read_root():
 
 
 @app.get("/items/{item_id}")
-def read_item(item_id: int, q: Optional[str] = None):
+def read_item(item_id: int, q: Union[str, None] = None):
     return {"item_id": item_id, "q": q}
 
 

docs/de/docs/index.md

@@ -149,7 +149,7 @@ $ pip install uvicorn[standard]
 * Create a file `main.py` with:
 
 ```Python
-from typing import Optional
+from typing import Union
 
 from fastapi import FastAPI
 
@@ -162,7 +162,7 @@ def read_root():
 
 
 @app.get("/items/{item_id}")
-def read_item(item_id: int, q: Optional[str] = None):
+def read_item(item_id: int, q: Union[str, None] = None):
     return {"item_id": item_id, "q": q}
 ```
 
@@ -172,7 +172,7 @@ def read_item(item_id: int, q: Optional[str] = None):
 If your code uses `async` / `await`, use `async def`:
 
 ```Python hl_lines="9  14"
-from typing import Optional
+from typing import Union
 
 from fastapi import FastAPI
 
@@ -185,7 +185,7 @@ async def read_root():
 
 
 @app.get("/items/{item_id}")
-async def read_item(item_id: int, q: Optional[str] = None):
+async def read_item(item_id: int, q: Union[str, None] = None):
     return {"item_id": item_id, "q": q}
 ```
 
@@ -264,7 +264,7 @@ Now modify the file `main.py` to receive a body from a `PUT` request.
 Declare the body using standard Python types, thanks to Pydantic.
 
 ```Python hl_lines="4  9-12  25-27"
-from typing import Optional
+from typing import Union
 
 from fastapi import FastAPI
 from pydantic import BaseModel
@@ -275,7 +275,7 @@ app = FastAPI()
 class Item(BaseModel):
     name: str
     price: float
-    is_offer: Optional[bool] = None
+    is_offer: Union[bool, None] = None
 
 
 @app.get("/")
@@ -284,7 +284,7 @@ def read_root():
 
 
 @app.get("/items/{item_id}")
-def read_item(item_id: int, q: Optional[str] = None):
+def read_item(item_id: int, q: Union[str, None] = None):
     return {"item_id": item_id, "q": q}
 
 

docs/en/docs/advanced/additional-status-codes.md

@@ -14,7 +14,7 @@ But you also want it to accept new items. And when the items didn't exist before
 
 To achieve that, import `JSONResponse`, and return your content there directly, setting the `status_code` that you want:
 
-```Python hl_lines="4  23"
+```Python hl_lines="4  25"
 {!../../../docs_src/additional_status_codes/tutorial001.py!}
 ```
 

docs/en/docs/advanced/testing-dependencies.md

@@ -28,7 +28,7 @@ To override a dependency for testing, you put as a key the original dependency (
 
 And then **FastAPI** will call that override instead of the original dependency.
 
-```Python hl_lines="26-27  30"
+```Python hl_lines="28-29  32"
 {!../../../docs_src/dependency_testing/tutorial001.py!}
 ```
 

docs/en/docs/deployment/docker.md

@@ -142,7 +142,7 @@ Successfully installed fastapi pydantic uvicorn
 * Create a `main.py` file with:
 
 ```Python
-from typing import Optional
+from typing import Union
 
 from fastapi import FastAPI
 
@@ -155,7 +155,7 @@ def read_root():
 
 
 @app.get("/items/{item_id}")
-def read_item(item_id: int, q: Optional[str] = None):
+def read_item(item_id: int, q: Union[str, None] = None):
     return {"item_id": item_id, "q": q}
 ```
 

docs/en/docs/index.md

@@ -148,7 +148,7 @@ $ pip install "uvicorn[standard]"
 * Create a file `main.py` with:
 
 ```Python
-from typing import Optional
+from typing import Union
 
 from fastapi import FastAPI
 
@@ -161,7 +161,7 @@ def read_root():
 
 
 @app.get("/items/{item_id}")
-def read_item(item_id: int, q: Optional[str] = None):
+def read_item(item_id: int, q: Union[str, None] = None):
     return {"item_id": item_id, "q": q}
 ```
 
@@ -171,7 +171,7 @@ def read_item(item_id: int, q: Optional[str] = None):
 If your code uses `async` / `await`, use `async def`:
 
 ```Python hl_lines="9  14"
-from typing import Optional
+from typing import Union
 
 from fastapi import FastAPI
 
@@ -184,7 +184,7 @@ async def read_root():
 
 
 @app.get("/items/{item_id}")
-async def read_item(item_id: int, q: Optional[str] = None):
+async def read_item(item_id: int, q: Union[str, None] = None):
     return {"item_id": item_id, "q": q}
 ```
 
@@ -263,7 +263,7 @@ Now modify the file `main.py` to receive a body from a `PUT` request.
 Declare the body using standard Python types, thanks to Pydantic.
 
 ```Python hl_lines="4  9-12  25-27"
-from typing import Optional
+from typing import Union
 
 from fastapi import FastAPI
 from pydantic import BaseModel
@@ -274,7 +274,7 @@ app = FastAPI()
 class Item(BaseModel):
     name: str
     price: float
-    is_offer: Optional[bool] = None
+    is_offer: Union[bool, None] = None
 
 
 @app.get("/")
@@ -283,7 +283,7 @@ def read_root():
 
 
 @app.get("/items/{item_id}")
-def read_item(item_id: int, q: Optional[str] = None):
+def read_item(item_id: int, q: Union[str, None] = None):
     return {"item_id": item_id, "q": q}
 
 

docs/en/docs/python-types.md

@@ -317,6 +317,45 @@ This also means that in Python 3.10, you can use `Something | None`:
     {!> ../../../docs_src/python_types/tutorial009_py310.py!}
     ```
 
+#### Using `Union` or `Optional`
+
+If you are using a Python version below 3.10, here's a tip from my very **subjective** point of view:
+
+* 🚨 Avoid using `Optional[SomeType]`
+* Instead ✨ **use `Union[SomeType, None]`** ✨.
+
+Both are equivalent and underneath they are the same, but I would recommend `Union` instead of `Optional` because the word "**optional**" would seem to imply that the value is optional, and it actually means "it can be `None`", even if it's not optional and is still required.
+
+I think `Union[str, SomeType]` is more explicit about what it means.
+
+It's just about the words and names. But those words can affect how you and your teammates think about the code.
+
+As an example, let's take this function:
+
+```Python hl_lines="1  4"
+{!../../../docs_src/python_types/tutorial009c.py!}
+```
+
+The parameter `name` is defined as `Optional[str]`, but it is **not optional**, you cannot call the function without the parameter:
+
+```Python
+say_hi()  # Oh, no, this throws an error! 😱
+```
+
+The `name` parameter is **still required** (not *optional*) because it doesn't have a default value. Still, `name` accepts `None` as the value:
+
+```Python
+say_hi(name=None)  # This works, None is valid 🎉
+```
+
+The good news is, once you are on Python 3.10 you won't have to worry about that, as you will be able to simply use `|` to define unions of types:
+
+```Python hl_lines="1  4"
+{!../../../docs_src/python_types/tutorial009c_py310.py!}
+```
+
+And then you won't have to worry about names like `Optional` and `Union`. 😎
+
 #### Generic types
 
 These types that take type parameters in square brackets are called **Generic types** or **Generics**, for example:
@@ -422,6 +461,9 @@ An example from the official Pydantic docs:
 
 You will see a lot more of all this in practice in the [Tutorial - User Guide](tutorial/index.md){.internal-link target=_blank}.
 
+!!! tip
+    Pydantic has a special behavior when you use `Optional` or `Union[Something, None]` without a default value, you can read more about it in the Pydantic docs about <a href="https://pydantic-docs.helpmanual.io/usage/models/#required-optional-fields" class="external-link" target="_blank">Required Optional fields</a>.
+
 ## Type hints in **FastAPI**
 
 **FastAPI** takes advantage of these type hints to do several things.