* The precision of this field is seconds; further precision will be truncated.
     */
    fun duration(
      duration: Long,
      unit: TimeUnit,
    ) = apply {
      val now = System.currentTimeMillis()
      validityInterval(now, now + unit.toMillis(duration))
    }

    /**
     * Adds a subject alternative name (SAN) to the certificate. This is usually a literal hostname,

///

To **learn the basics of HTTPS**, from a consumer perspective, check <a href="https://howhttps.works/" class="external-link" target="_blank">https://howhttps.works/</a>.

Now, from a **developer's perspective**, here are several things to keep in mind while thinking about HTTPS:

* For HTTPS, **the server** needs to **have "certificates"** generated by a **third party**.

 *
 * <p>See the Guava User Guide article on <a href=
 * "https://github.com/google/guava/wiki/FunctionalExplained">the use of functional types</a>.
 *
 * <h3>For Java 8+ users</h3>
 *
 * <p>This interface is now a legacy type. Use {@code java.util.function.Supplier} (or the
 * appropriate primitive specialization such as {@code IntSupplier}) instead whenever possible.

                .append(" (");
        format.format(message, contentLength);

        Duration duration =
                Duration.between(Instant.ofEpochMilli(resource.getTransferStartTime()), MonotonicClock.now());
        if ((duration.getSeconds() | duration.getNano()) > 0) { // duration.isPositive()
            long bytesPerSecond = Math.round(contentLength / (double) duration.toSeconds());
            message.append(" at ");

	if ri == nil {
		return errInvalidArgument
	}
	now := UTCNow()
	ri.mu.Lock()
	var (
		format, version uint16
		jobTyp          string
	)

	if now.Sub(ri.LastUpdate) >= duration {
		switch job.Type() {
		case madmin.BatchJobReplicate:
			format = batchReplFormat
			version = batchReplVersion

The exception handler will receive a `Request` and the exception.

{* ../../docs_src/handling_errors/tutorial004_py39.py hl[2,14:19] *}

Now, if you go to `/items/foo`, instead of getting the default JSON error with:

```JSON
{
    "detail": [
        {
            "loc": [
                "path",
                "item_id"
            ],

 * java.util.function.Function} in a context where a {@code com.google.common.base.Function} is
 * needed, use {@code function::apply}.
 *
 * <p>This interface is now a legacy type. Use {@code java.util.function.Function} (or the
 * appropriate primitive specialization such as {@code ToIntFunction}) instead whenever possible.

# OAuth2 with Password (and hashing), Bearer with JWT tokens { #oauth2-with-password-and-hashing-bearer-with-jwt-tokens }

Now that we have all the security flow, let's make the application actually secure, using <abbr title="JSON Web Tokens">JWT</abbr> tokens and secure password hashing.

This code is something you can actually use in your application, save the password hashes in your database, etc.

Notice that now we don't create a default instance `settings = Settings()`.

### The main app file { #the-main-app-file }

Now we create a dependency that returns a new `config.Settings()`.

{* ../../docs_src/settings/app02_an_py39/main.py hl[6,12:13] *}

/// tip

We'll discuss the `@lru_cache` in a bit.

For now you can assume `get_settings()` is a normal function.

In this case, it will be mounted at the path `/subapi`:

{* ../../docs_src/sub_applications/tutorial001_py39.py hl[11, 19] *}

### Check the automatic API docs { #check-the-automatic-api-docs }

Now, run the `fastapi` command with your file:

<div class="termy">

```console
$ fastapi dev main.py

<span style="color: green;">INFO</span>:     Uvicorn running on http://127.0.0.1:8000 (Press CTRL+C to quit)
```