### DNS

Now let's focus on all the actual HTTPS parts.

First, the browser would check with the **DNS servers** what is the **IP for the domain**, in this case, `someapp.example.com`.

The DNS servers would tell the browser to use some specific **IP address**. That would be the public IP address used by your server, that you configured in the DNS servers.

<img src="/img/deployment/https/https01.svg">

### TLS Handshake Start

    /**
     * Sets the servers whose passwords should be decrypted.
     *
     * @param servers The servers to decrypt, may be {@code null}.
     * @return This request, never {@code null}.
     */
    SettingsDecryptionRequest setServers(List<Server> servers);

    /**
     * Gets the proxies whose passwords should be decrypted.
     *
     * @return The proxies to decrypt, never {@code null}.
     */
    List<Proxy> getProxies();

		tries++
		switch {
		case errors.Is(err, errNotFirstDisk):
			// Fresh setup, wait for first server to be up.
			logger.Info("Waiting for the first server to format the drives (elapsed %s)\n", getElapsedTime())
		case errors.Is(err, errFirstDiskWait):
			// Fresh setup, wait for other servers to come up.
			logger.Info("Waiting for all other servers to be online to format the drives (elapses %s)\n", getElapsedTime())

 * They don't specify whether a specific proxy server should be used or how to authenticate with that proxy server.

They're also concrete: each URL identifies a specific path (like `/square/okhttp`) and query (like `?q=sharks&lang=en`). Each webserver hosts many URLs.

from dirty_equals import IsOneOf
from fastapi import FastAPI
from fastapi.testclient import TestClient

app = FastAPI(
    servers=[
        {"url": "/", "description": "Default, relative server"},
        {
            "url": "http://staging.localhost.tiangolo.com:8000",
            "description": "Staging but actually localhost still",
        },
        {"url": "https://prod.example.com"},
    ]
)


@app.get("/foo")
def foo():

browser("Browser")
proxy["Proxy on http://0.0.0.0:9999/api/v1/app"]
server["Server on http://127.0.0.1:8000/app"]

browser --> proxy
proxy --> server
```

/// tip

📢 `0.0.0.0` 🛎 ⚙️ ⛓ 👈 📋 👂 🔛 🌐 📢 💪 👈 🎰/💽.

///

🩺 🎚 🔜 💪 🗄 🔗 📣 👈 👉 🛠️ `server` 🔎 `/api/v1` (⛅ 🗳). 🖼:

```JSON hl_lines="4-8"
{
    "openapi": "3.0.2",
    // More stuff here
    "servers": [
        {
            "url": "/api/v1"

browser("Browser")
proxy["Proxy on http://0.0.0.0:9999/api/v1/app"]
server["Server on http://127.0.0.1:8000/app"]

browser --> proxy
proxy --> server
```

/// tip | "Dica"

O IP `0.0.0.0` é comumente usado para significar que o programa escuta em todos os IPs disponíveis naquela máquina/servidor.

///

A interface de documentação também precisaria do OpenAPI schema para declarar que API `server` está localizado em `/api/v1` (atrás do proxy). Por exemplo:

Recommendations
---------------

Typically servers need a held certificate plus a chain of intermediates. Servers only need the
private key for their own certificate. The chain served by a server doesn't need the root
certificate.

The trusted roots don't need to be the same for client and server when using client authentication.
Clients might rely on the platform certificates and servers might use a private

     *
     * @return The decrypted server or {@code null}.
     */
    Server getServer();

    /**
     * Gets the decrypted servers.
     *
     * @return The decrypted server, can be empty but never {@code null}.
     */
    List<Server> getServers();

    /**
     * Gets the decrypted proxy. This is a convenience method to retrieve the first element from {@link #getProxies()}.
     *

## ASGI Servers

Let's go a little deeper into the details.

FastAPI uses a standard for building Python web frameworks and servers called <abbr title="Asynchronous Server Gateway Interface">ASGI</abbr>. FastAPI is an ASGI web framework.