# Handling Errors { #handling-errors }

There are many situations in which you need to notify an error to a client that is using your API.

This client could be a browser with a frontend, a code from someone else, an IoT device, etc.

You could need to tell the client that:

* The client doesn't have enough privileges for that operation.
* The client doesn't have access to that resource.
* The item the client was trying to access doesn't exist.
* etc.

    install_command: 'yum install -y'
  )
end

def rpm_docker(config)
  config.vm.provision 'install Docker using yum', type: 'shell', inline: <<-SHELL
    # Install prerequisites
    yum install -y yum-utils device-mapper-persistent-data lvm2

    # Add repository
    yum-config-manager -y --add-repo https://download.docker.com/linux/centos/docker-ce.repo

    # Install Docker

Como parte de eso, necesitaba investigar, probar y usar muchas alternativas.

La historia de **FastAPI** es en gran parte la historia de sus predecesores.

Como se dice en la sección [Alternativas](alternatives.md):

<blockquote markdown="1">

**FastAPI** no existiría si no fuera por el trabajo previo de otros.

///

### Pydantic v1 and v2 on the same app { #pydantic-v1-and-v2-on-the-same-app }

It's **not supported** by Pydantic to have a model of Pydantic v2 with its own fields defined as Pydantic v1 models or vice versa.

```mermaid
graph TB
    subgraph "❌ Not Supported"
        direction TB
        subgraph V2["Pydantic v2 Model"]
            V1Field["Pydantic v1 Model"]
        end

///

### Pydantic v1 e v2 na mesma aplicação { #pydantic-v1-and-v2-on-the-same-app }

Não é **suportado** pelo Pydantic ter um modelo do Pydantic v2 com campos próprios definidos como modelos do Pydantic v1, ou vice-versa.

```mermaid
graph TB
    subgraph "❌ Not Supported"
        direction TB
        subgraph V2["Pydantic v2 Model"]
            V1Field["Pydantic v1 Model"]
        end

- DRA: Device taints enable DRA drivers or admins to mark device as unusable, which prevents allocating them. Pods may also get evicted at runtime if a device becomes unusable, depending on the severity of the taint and whether the claim tolerates the taint. ([#130447](https://github.com/kubernetes/kubernetes/pull/130447), [@pohly]...

class Item(BaseModel):
    name: str
    description: str | None = None


@app.get("/items/me")
async def get_item() -> Item:
    return Item(name="Plumbus", description="All-purpose home device")
```

* Fix issue where on re-registration of device plugin, `allocatable` was not getting updated. This issue makes devices invisible to the Kubelet if device plugin restarts. Only work-around, if this fix is not there, is to restart the kubelet and then start device plugin. ([#63118](https://github.com/kubernetes/kubernetes/pull/63118), [@vikaschoudhary16](https://github.com/vikaschoudhary16))

     * clone. The only requirement is that invocations of {@link #addRepository(Repository)} on the clone do not affect
     * the state of the original resolver and vice versa.
     *
     * @return The cloned resolver, never {@code null}.
     */
    ModelResolver newCopy();

  /**
   * Returns a view of the complement of this {@code RangeSet}.
   *
   * <p>The returned view supports the {@link #add} operation if this {@code RangeSet} supports
   * {@link #remove}, and vice versa.
   */
  RangeSet<C> complement();

  /**
   * Returns a view of the intersection of this {@code RangeSet} with the specified range.
   *