## [Requests](https://square.github.io/okhttp/4.x/okhttp/okhttp3/-request/)

Each HTTP request contains a URL, a method (like `GET` or `POST`), and a list of headers. Requests may also contain a body: a data stream of a specific content type.

## [Responses](https://square.github.io/okhttp/4.x/okhttp/okhttp3/-response/)

          )
      }

    /**
     * @param host either a regular hostname, International Domain Name, IPv4 address, or IPv6
     * address.
     */
    fun host(host: String) =
      apply {
        val encoded =
          host.percentDecode().toCanonicalHost()
            ?: throw IllegalArgumentException("unexpected host: $host")
        this.host = encoded
      }

    fun port(port: Int) =

 *     possible for shared exchanges to make requests to different host names! See
 *     [RealConnection.isEligible] for details.
 *
 *  3. Attempt plans from prior connect attempts for this call. These occur as either follow-ups to
 *     failed connect attempts (such as trying the next [ConnectionSpec]), or as attempts that lost
 *     a race in fast follow-up.
 *

* `@app.get()`
* `@app.post()`
* `@app.put()`
* `@app.delete()`
* etc.

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

!!! note
    Notice that `status_code` is a parameter of the "decorator" method (`get`, `post`, etc). Not of your *path operation function*, like all the parameters and body.

     * Sets the socket factory and trust manager used to secure HTTPS connections. If unset, the
     * system defaults will be used.
     *
     * Most applications should not call this method, and instead use the system defaults. Those
     * classes include special optimizations that can be lost if the implementations are decorated.
     *
     * If necessary, you can create and configure the defaults yourself with the following code:
     *

    return response.body().string();
  }
}
```


Post to a Server
----------------

This program posts data to a service. [Full source][post_example].

```java
public static final MediaType JSON = MediaType.get("application/json");

OkHttpClient client = new OkHttpClient();

String post(String url, String json) throws IOException {
  RequestBody body = RequestBody.create(json, JSON);

      apply {
        this.trustedCertificates += certificate
      }

    /**
     * Add all of the host platform's trusted root certificates. This set varies by platform
     * (Android vs. Java), by platform release (Android 4.4 vs. Android 9), and with user
     * customizations.
     *
     * Most TLS clients that connect to hosts on the public Internet should call this method.

      return routes[nextRouteIndex++]
    }
  }

  companion object {
    /** Obtain a host string containing either an actual host name or a numeric IP address. */
    val InetSocketAddress.socketHost: String get() {
      // The InetSocketAddress was specified with a string (either a numeric IP or a host name). If
      // it is a name, all IPs for that name should be tried. If it is an IP address, only that IP

The user of your API (an external developer) will create an invoice in your API with a POST request.

Then your API will (let's imagine):

* Send the invoice to some customer of the external developer.
* Collect the money.
* Send a notification back to the API user (the external developer).
    * This will be done by sending a POST request (from *your API*) to some *external API* provided by that external developer (this is the "callback").

      isDaemon = daemon
    }
  }

internal fun HttpUrl.toHostHeader(includeDefaultPort: Boolean = false): String {
  val host =
    if (":" in host) {
      "[$host]"
    } else {
      host
    }
  return if (includeDefaultPort || port != defaultPort(scheme)) {
    "$host:$port"
  } else {
    host
  }
}

/** Returns a [Locale.US] formatted [String]. */
internal fun format(
  format: String,