# CORS (Cross-Origin Resource Sharing)

<a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/CORS" class="external-link" target="_blank">CORS or "Cross-Origin Resource Sharing"</a> refers to the situations when a frontend running in a browser has JavaScript code that communicates with a backend, and the backend is in a different "origin" than the frontend.

## Origin

  // be one of the following values:
  // * Exact: Matches the URL path exactly.
  // * Prefix: Matches based on a URL path prefix split by '/'. Matching is
  //   done on a path element by element basis. A path element refers is the
  //   list of labels in the path split by the '/' separator. A request is a
  //   match for path p if every p is an element-wise prefix of p of the

         alt="Istio logo" title="Istio" height="100" width="100" />
</a>

---

Here we'll see an example using **<a href="https://www.couchbase.com/" class="external-link" target="_blank">Couchbase</a>**, a <abbr title="Document here refers to a JSON object (a dict), with keys and values, and those values can also be other JSON objects, arrays (lists), numbers, strings, booleans, etc.">document</abbr> based NoSQL database.

You can adapt it to any other NoSQL database like:

// CSIDriver objects are non-namespaced.
message CSIDriver {
  // Standard object metadata.
  // metadata.Name indicates the name of the CSI driver that this object
  // refers to; it MUST be the same name returned by the CSI GetPluginName()
  // call for that driver.
  // The driver name must be 63 characters or less, beginning and ending with

Here the `app` variable will be an "instance" of the class `FastAPI`.

This will be the main point of interaction to create all your API.

### Step 3: create a *path operation*

#### Path

"Path" here refers to the last part of the URL starting from the first `/`.

So, in a URL like:

```
https://example.com/items/foo
```

...the path would be:

```
/items/foo
```

!!! info

    !!! tip
        Prefer to use the `Annotated` version if possible.

    ```Python hl_lines="6"
    {!> ../../../docs_src/security/tutorial001.py!}
    ```

!!! tip
    Here `tokenUrl="token"` refers to a relative URL `token` that we haven't created yet. As it's a relative URL, it's equivalent to `./token`.

Component settings are those that necessarily refer to a particular Deployment or Service. For example, the number
of Pilot replicas is a component setting, because it refers to a component which is a Deployment in the
cluster. Most K8s platform settings are necessarily component settings.
The available features and the components that comprise each feature are as follows:

| Feature | Components |

### Inbound

Traffic entering a pod over HBONE will be handled by the "inbound" code path, on port 15008.

Incoming requests have multiple "layers": TLS wrapping HTTP CONNECT that is wrapping the user's connection.

To unwrap the first layer, we terminate TLS.
As part of this, we need to pick the correct certificate to serve on behalf of the destination workload.

**FastAPI** 💪 🛠️ ⏮️ 🙆 <abbr title="Distributed database (Big Data), also 'Not Only SQL'">☁</abbr>.

📥 👥 🔜 👀 🖼 ⚙️ **<a href="https://www.couchbase.com/" class="external-link" target="_blank">🗄</a>**, <abbr title="Document here refers to a JSON object (a dict), with keys and values, and those values can also be other JSON objects, arrays (lists), numbers, strings, booleans, etc.">📄</abbr> 🧢 ☁ 💽.

👆 💪 🛠️ ⚫️ 🙆 🎏 ☁ 💽 💖:

* **✳**
* **👸**
* **✳**