HTTP 306 (Unused)

Overview

The HTTP 306 (Unused) status code was historically reserved in the HTTP/1.1 specification but is not currently used. It was originally intended to be used as “306 Switch Proxy,” but this status code was deprecated and is now reserved for future use.

Purpose

The HTTP 306 status code was initially proposed for indicating that subsequent requests should use the specified proxy. However, this status code is currently obsolete and reserved for potential future use.

Usage

Client Behavior:

1. Send Request: The client sends an HTTP request.
2. Receive Response: The client would theoretically receive the HTTP 306 status code, indicating a switch in proxy usage (not in use).

Server Behavior:

1. Process Request: The server processes the request.
2. Send Response: The server would theoretically send a 306 (Unused) response, suggesting a switch in proxy (not in use).

Scenarios

• Historical Use: Initially proposed for proxy switching scenarios.
• Reserved Status Code: Currently reserved and not in practical use.

Sequence Diagram

Illustrating the theoretical process for an HTTP 306 response (not in use):

sequenceDiagram
    participant Client
    participant Server as Web Server

    Note over Client: Client sends a request (theoretical context)
    Client->>Server: GET /resource HTTP/1.1
    Note over Server: Server issues a 306 response (not in use)
    Server->>Client: HTTP/1.1 306 (Unused)

Curl Request and Response Example

Sending a request using Curl that would theoretically lead to a 306 response (not in use):

curl -i http://example.com/resource
# Theoretical response: HTTP/1.1 306 (Unused)

PHP cURL Request and Response Example

PHP script using cURL to handle a request that might theoretically result in a 306 response (not in use):

<?php
$ch = curl_init('http://example.com/resource');
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
$response = curl_exec($ch);
if (curl_getinfo($ch, CURLINFO_HTTP_CODE) == 306) {
    echo "Theoretically, this would suggest a switch proxy directive (not in use).";
}
curl_close($ch);
?>

Python Request and Response Example

Python script to send a GET request in a theoretical context where a 306 response might be issued (not in use):

import requests
response = requests.get('http://example.com/resource')
if response.status_code == 306:
    print("Theoretically, this would suggest a switch proxy directive (not in use)")

Apache Configuration for HTTP 306 (Unused)

Apache server configuration for a theoretical context where a 306 response might be used (not in use):

<VirtualHost *:80>
    ServerName example.com
    # Theoretical configuration directives for 306 response (not in use)
    # ...
</VirtualHost>

NGINX Configuration for HTTP 306 (Unused)

Setting up NGINX in a theoretical context where a 306 response might be issued (not in use):

server {
    listen 80;
    server_name example.com;
    location /resource {
        # Theoretical configurations for 306 response (not in use)
        # ...
    }
}

HTTP 305 Use Proxy HTTP 307 Temporary Redirect