How to display list data from SqlAlchemy Query using fastAPI

So, I have been trying to learn Python Full-Stack web development using fastAPI. Most of my website works properly but I am having trouble with sending the list of Query using FASTAPI.

I get this error.

{
  "detail": [
    {
      "loc": [
        "path",
        "id"
      ],
      "msg": "value is not a valid integer",
      "type": "type_error.integer"
    }
  ]
}

JavaScript
​x
 
{
  "detail": [
    {
      "loc": [
        "path",
        "id"
      ],
      "msg": "value is not a valid integer",
      "type": "type_error.integer"
    }
  ]
}
​

This is my FastAPI router code.

@router.get("/get/all", response_model=List[ComicViewable])
def list_of_all_comics(db: Session = Depends(get_db)):
    comics = comic_func.list_comics(db)
    if not comics:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND,
                            detail="No Comics have been created.")
    return comics

JavaScript
 
@router.get("/get/all", response_model=List[ComicViewable])
def list_of_all_comics(db: Session = Depends(get_db)):
    comics = comic_func.list_comics(db)
    if not comics:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND,
                            detail="No Comics have been created.")
    return comics
​

This is the function that returns the list of all comics stored in the database.

def list_comics(db: Session):
    return db.query(Comic).all()

JavaScript
 
def list_comics(db: Session):
    return db.query(Comic).all()
​

and my pydantic response class

class ComicViewable(BaseModel):
    title: str
    description: str
    date_created: date
    is_ongoing: bool
    is_public: bool

    class Config:
        orm_mode = True

JavaScript
 
class ComicViewable(BaseModel):
    title: str
    description: str
    date_created: date
    is_ongoing: bool
    is_public: bool
​
    class Config:
        orm_mode = True
​
​

I don’t know what I’m doing wrong here. I have read the FASTAPI help documentation and in there they also use List[PydanticClassName] to return a list of database queries, but for some reason, it is not working for me.

EDIT: So, I checked the response of list_comics() function. It does indeed return the right response. I tested it by printing the comic.title in a Jinja2 template.

{% block content %}
<div class="ui segment">
    <div class="two column middle aligned grid">
        {% for comic in comics %}
        <h2>{{comic.title}}</h2>
        {% endfor %}
    </div>
</div>
{% endblock %}

JavaScript
 
{% block content %}
<div class="ui segment">
    <div class="two column middle aligned grid">
        {% for comic in comics %}
        <h2>{{comic.title}}</h2>
        {% endfor %}
    </div>
</div>
{% endblock %}
​

So the error seems to be happening either in the pydantic class model or FastAPI router.

Answer

This solution suggested by @MatsLindh solved it.

That is not the endpoint being loaded; the error message complains about an endpoint with id set (i.e. /get/{id} or something similar). You probably have that endpoint defined before your /get/all endpoint, and since all is not an integer, it throws the given error.

This solved my problem, As I had another endpoint before the /get/all endpoint named as /get/{id} which was causing the error.

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Answer