# Router Prefix

* Complex APIs can have very complex and long routes
* Router Prefixes allow us to have that stored
* We can additionally replace the route with <mark style="color:yellow;">`"/"`</mark>

```python
# Stored Prefix
router = APIRouter(
    prefix="/posts"
)

# We no longer need "/posts" and can replace it with "/"

# Before:
@router.get("/posts", response_model=List[schemas.PostResponse])
def get_posts(db: Session = Depends(get_db)):


    posts = db.query(models.Post).all()

    return posts
    
# After:
@router.get("/", response_model=List[schemas.PostResponse])
def get_posts(db: Session = Depends(get_db)):


    posts = db.query(models.Post).all()

    return posts
```

How it looks with the full code for the <mark style="color:green;">`users.py`</mark> file&#x20;

```python
from fastapi import Depends, FastAPI, Response, status, HTTPException, APIRouter
from .. import models, schemas, utils
from sqlalchemy.orm import Session
from app.database import get_db

router = APIRouter(
    prefix="/users"
)

# Create USER
@router.post("/", status_code=status.HTTP_201_CREATED, response_model=schemas.UserOut)
def create_user(user: schemas.UserCreate, db: Session = Depends(get_db)):

    # Hash the Password - user.password
    hashed_password = utils.hash(user.password)
    user.password = hashed_password

    new_user = models.User(**user.dict())

    db.add(new_user)
    db.commit()
    db.refresh(new_user)

    return new_user


# Get USER by ID
@router.get("/{id}", response_model=schemas.UserOut) # This will append it to "/users" + id
def get_user(id: int, db: Session = Depends(get_db)):

    user = db.query(models.User).filter(models.User.id == id).first()

    if not user:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail=f"User with id: {id} does not exist")

    return user
```


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