add an extremely simple example proxy and basic usage

Author: SjonHortensius

README.md

@@ -1,15 +1,15 @@
 Postcode.nl Api Client
 =============
 
-PHP Api client for the [Postcode.nl Api](https://api.postcode.nl/documentation/). 
+PHP Api client for the [Postcode.nl Api](https://api.postcode.nl/documentation/).
 
 
 How to install
 =============
 
 ### Composer
 
-Get package `postcode-nl/api-client`. 
+Get package `postcode-nl/api-client`.
 
 ### From this repository
 

example/README.md

@@ -0,0 +1,33 @@
+Example Postcode.nl Api Proxy
+=============
+
+PHP Api proxy for the [Postcode.nl Api](https://api.postcode.nl/documentation/).
+
+
+Usage
+=============
+
+This directory serves as an extremely simple proxy example for the supplied client.
+Set the correct `API_KEY` and `API_SECRET` and optional `PLATFORM` and you can call
+any supported method, for example:
+
+### Show all valid data from a valid postal code
+`.../example/index.php?action=dutchAddressByPostcode&data[]=2012es&data[]=30`
+
+### Return an exception for non-existing addresses
+`.../example/index.php?action=dutchAddressByPostcode&data[]=2012es&data[]=31`
+
+### Show autocomplete results for a German lookup
+`.../example/index.php?action=internationalAutocomplete&data[]=deu&data[]=strasse&data[]=CLIENT_SESSION_FROM_COOKIE`
+
+Please only use this proxy as an example for your own implementation.
+What you should add:
+
+* Don't allow random calls but implement what you use in a custom wrapper
+* Add caching to prevent fetching the same data over and over
+* Add Session by reading `$_COOKIE`, don't pass it in the URL
+
+License
+=============
+
+The code is available under the Simplified BSD License, see the included LICENSE file.

example/index.php

@@ -0,0 +1,28 @@
+<?php
+
+define('API_KEY',    /* as received by mail after signing up */);
+define('API_SECRET', /* as received by mail after signing up */);
+define('PLATFORM', 'example proxy');
+
+
+// this will load exceptions when they occur
+spl_autoload_register(function($class){
+	if (0 === strpos($class, 'PostcodeNl\\'))
+		require(__DIR__ .'/../src/'. str_replace('\\', '/', $class) .'.php');
+});
+
+header('Content-Type: application/json');
+
+try
+{
+	if (0 !== strpos($_GET['action'], 'international') && 0 !== strpos($_GET['action'], 'dutchAddress'))
+		throw new Exception('This example only supports calls to international or dutchAddress methods');
+
+	$client = new PostcodeNl\Api\Client(API_KEY, API_SECRET, PLATFORM);
+	print json_encode(call_user_func_array([$client, $_GET['action']], $_GET['data'] ?? []));
+}
+catch (Exception $e)
+{
+	http_response_code(400);
+	print json_encode(['Exception' => $e->getMessage()]);
+}