tiangolo/fastapi · error · HTTPException

Item not found, there's only a plumbus here

Error message

Item not found, there's only a plumbus here

What it means

Non-Annotated variant of error 26: same 404 "Item not found, there's only a plumbus here" with the re-raising yield dependency. Fires for unknown item_ids other than "portal-gun".

Source

Thrown at docs_src/dependencies/tutorial008d_py310.py:25

    pass


def get_username():
    try:
        yield "Rick"
    except InternalError:
        print("We don't swallow the internal error here, we raise again 😎")
        raise


@app.get("/items/{item_id}")
def get_item(item_id: str, username: str = Depends(get_username)):
    if item_id == "portal-gun":
        raise InternalError(
            f"The portal gun is too dangerous to be owned by {username}"
        )
    if item_id != "plumbus":
        raise HTTPException(
            status_code=404, detail="Item not found, there's only a plumbus here"
        )
    return item_id

View on GitHub (pinned to 42a41db11f)

Solutions

1. Call /items/plumbus.
2. Avoid /items/portal-gun in this variant (InternalError propagates as 500).
3. Keep 404 detail consistent across Annotated/non-Annotated variants.
4. Test all three id branches.

Example fix

# before
if item_id != "plumbus":
    raise HTTPException(status_code=404, detail="Item not found, there's only a plumbus here")

# after
if item_id != "plumbus":
    raise HTTPException(status_code=404, detail=f"Item '{item_id}' not found")

if item_id != "plumbus":
    raise ValueError("only plumbus is safe")

def is_safe_item(item_id: str) -> bool:
    return item_id == "plumbus"

r = client.get(f"/items/{item_id}")
if r.status_code == 404:
    ...
elif r.status_code >= 500:
    # re-raised InternalError (e.g. portal-gun)
    ...

When it happens

Trigger: GET /items/<not-plumbus-and-not-portal-gun> in the tutorial008d_py310 endpoint.

Common situations: Unknown resource ids; clients expecting the swallowed-error behavior from 008c now seeing 500s on portal-gun because the dependency re-raises.

Related errors

• Item not found
• Item not found, there's only a plumbus here
• Item not found, there's only a plumbus here
• Item not found, there's only a plumbus here
• Item not found

AI-assisted analysis of tiangolo/fastapi@42a41db11f (2026-08-04). Data as JSON: /data/errors/48a554ee92d6b27f.json. Report an issue: GitHub.