@ -124,9 +125,9 @@ You import and create a `FastAPI` class as normally:
### Import the `APIRouter`
But this time we are not adding path operations directly with the `FastAPI``app`.
But this time we are not adding *path operations* directly with the `FastAPI``app`.
We import the `APIRouter`s from the other files:
We import the other submodules that have `APIRouter`s:
```Python hl_lines="3 4"
{!./src/bigger_applications/app/main.py!}
@ -140,22 +141,21 @@ As the file `app/routers/items.py` is part of the same Python package, we can im
The section:
```Python
from .routers.items import router
from .routers import items
```
Means:
* Starting in the same package that this module (the file `app/main.py`) lives in (the directory `app/`)...
* look for the subpackage `routers` (the directory at `app/routers/`)...
* and from it, the submodule `items` (the file at `app/routers/items.py`)...
* and from that submodule, import the variable `router`.
* and from it, import the submodule `items` (the file at `app/routers/items.py`)...
The variable `router` is the same one we created in the file `app/routers/items.py`. It's an `APIRouter`.
The module `items` will have a variable `router` (`items.router`). This is the same one we created in the file `app/routers/items.py`. It's an `APIRouter`.
We could also import it like:
```Python
from app.routers.items import router
from app.routers import items
```
!!! info
@ -168,20 +168,20 @@ from app.routers.items import router
### Avoid name collisions
We are importing a variable named `router` from the submodule `items`.
We are importing the submodule `items` directly, instead of importing just its variable `router`.
But we also have another variable named `router` in the submodule `users`.
This is because we also have another variable named `router` in the submodule `users`.
If we import one after the other, like:
If we had imported one after the other, like:
```Python
from .routers.items import router
from .routers.users import router
```
The `router` from `users` will overwrite the one form `items` and we won't be able to use them at the same time.
The `router` from `users` would overwrite the one from `items` and we wouldn't be able to use them at the same time.
So, to be able to use both of them in the same file, we rename them while importing them using `as`:
So, to be able to use both of them in the same file, we import the submodules directly:
```Python hl_lines="3 4"
{!./src/bigger_applications/app/main.py!}
@ -190,18 +190,21 @@ So, to be able to use both of them in the same file, we rename them while import
### Include an `APIRouter`
Now, let's include the router from the submodule `users`, now in the variable `users_router`:
Now, let's include the `router` from the submodule `users`:
```Python hl_lines="8"
{!./src/bigger_applications/app/main.py!}
```
!!! info
`users.router` contains the `APIRouter` inside of the file `app/routers/users.py`.
With `app.include_router()` we can add an `APIRouter` to the main `FastAPI` application.
It will include all the routes from that router as part of it.
!!! note "Technical Details"
It will actually internally create a path operation for each path operation that was declared in the `APIRouter`.
It will actually internally create a *path operation* for each *path operation* that was declared in the `APIRouter`.
So, behind the scenes, it will actually work as if everything was the same single app.
@ -216,23 +219,25 @@ It will include all the routes from that router as part of it.
### Include an `APIRouter` with a prefix
Now, let's include the router form the `items` submodule, now in the variable `items_router`.
Now, let's include the router form the `items` submodule.
But, remember that we were lazy and didn't add `/items/` to all the path operations?
But, remember that we were lazy and didn't add `/items/`nor `tags`to all the *path operations*?
We can add a prefix to all the path operations using the parameter `prefix` of `app.include_router()`.
As the path of each path operation has to start with `/`, like in:
```Python hl_lines="1"
@router.get("/{item_id}", tags=["items"])
@router.get("/{item_id}")
async def read_item(item_id: str):
...
```
...the prefix must not include a final `/`.
So, the prefix in this case would be `/items`:
So, the prefix in this case would be `/items`.
And we can also add a list of `tags` that will be applied to all the *path operations* included in this router:
```Python hl_lines="9"
{!./src/bigger_applications/app/main.py!}
@ -245,8 +250,12 @@ The end result is that the item paths are now:
...as we intended.
And they are marked with a list of tags that contain a single string `"items"`.
These "tags" are especially useful for the automatic interactive documentation systems (using OpenAPI).
!!! check
The `prefix` parameter is (as in many other cases) just a feature from **FastAPI** to help you avoid code duplication.
The `prefix`and `tags`parameters are (as in many other cases) just a feature from **FastAPI** to help you avoid code duplication.
!!! tip
@ -279,6 +288,6 @@ uvicorn app.main:app --reload
And open the docs at <ahref="http://127.0.0.1:8000/docs"target="_blank">http://127.0.0.1:8000/docs</a>.
You will see the automatic API docs, including the paths from all the submodules:
You will see the automatic API docs, including the paths from all the submodules, using the correct paths (and prefixes) and the correct tags:
euri10
6 years ago
Sebastián Ramírez