return // If we don't have permission to compute the HMAC, don't change the cred.
	}
	if err != nil {
		logger.Fatal(err, "Unable to generate root access key using KMS")
	}

	sKey, err := GlobalKMS.MAC(GlobalContext, &kms.MACRequest{Message: []byte("root secret key")})
	if err != nil {
		// Here, we must have permission. Otherwise, we would have failed earlier.

# Security - First Steps

Let's imagine that you have your **backend** API in some domain.

And you have a **frontend** in another domain or in a different path of the same domain (or in a mobile application).

And you want to have a way for the frontend to authenticate with the backend, using a **username** and **password**.

We can use **OAuth2** to build that with **FastAPI**.

// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

//go:generate msgp -file=$GOFILE

package cmd

import (
	"context"

    * This is comparable to using the model's `.model_dump()` method again, but it makes sure (and converts) the values to data types that can be converted to JSON, for example, `datetime` to `str`.
* Save the data to your DB.
* Return the updated model.

//// tab | Python 3.10+

```Python hl_lines="28-35"
{!> ../../docs_src/body_updates/tutorial002_py310.py!}
```

////

//// tab | Python 3.9+

  private final transient int size;

  /*
   * We have some considerable complexity in these create methods because of
   * Builder.buildKeepingLast(). The same Builder might be called with buildKeepingLast() and then
   * buildOrThrow(), or vice versa. So in particular, if we modify alternatingKeysAndValues to
   * eliminate duplicate keys (for buildKeepingLast()) then we have to ensure that a later call to

### Generate a TypeScript Client

Now that we have the app with the models, we can generate the client code for the frontend.

#### Install `openapi-ts`

You can install `openapi-ts` in your frontend code with:

<div class="termy">

```console
$ npm install @hey-api/openapi-ts --save-dev

---> 100%
```

</div>

#### Generate Client Code

	}

	for _, count := range vidMap {
		// do we have enough common versions
		// that have enough quorum to satisfy
		// the etag.
		if count >= quorum {
			return etags
		}
	}

	return make([]string, len(partsMetadata))
}

// Extracts list of times from FileInfo slice and returns, skips
// slice elements which have errors.

 * A set of tasks that are executed in sequential order.
 *
 * Work within queues is not concurrent. This is equivalent to each queue having a dedicated thread
 * for its work; in practice a set of queues may share a set of threads to save resources.
 */
class TaskQueue internal constructor(
  internal val taskRunner: TaskRunner,
  internal val name: String,
) {
  val lock: ReentrantLock = ReentrantLock()

  internal var shutdown = false

   */
  public static final String RTT = "RTT";

  /**
   * The HTTP <a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Save-Data">{@code
   * Save-Data}</a> header field name.
   *
   * @since 31.0
   */
  public static final String SAVE_DATA = "Save-Data";

  /**
   * The HTTP <a
   * href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Viewport-Width">{@code

   *
   * <p>The collections returned by {@link Multimap#keySet()}, {@link Multimap#keys()}, and {@link
   * Multimap#asMap()} will iterate through the keys in the order that they were first added to the
   * multimap, save that if all values associated with a key are removed and then the key is added
   * back into the multimap, that key will come last in the key iteration order.
   */