From 52b04ce8d24f25160c641f98a53b951b08dd8c21 Mon Sep 17 00:00:00 2001
From: Chris Deighton <chris@serato.com>
Date: Wed, 25 Jul 2018 22:31:37 +1200
Subject: [PATCH] Add `Serato\SwsApp\Slim\Middleware\GeoIpLookup` middleware

---
 .gitignore                                |   1 +
 composer.json                             |   3 +-
 phpunit.xml                               |   6 ++
 src/Slim/Middleware/GeoIpLookup.php       |  78 ++++++++++++++
 tests/Slim/Middleware/GeoIpLookupTest.php | 120 ++++++++++++++++++++++
 5 files changed, 207 insertions(+), 1 deletion(-)
 create mode 100644 src/Slim/Middleware/GeoIpLookup.php
 create mode 100644 tests/Slim/Middleware/GeoIpLookupTest.php

diff --git a/.gitignore b/.gitignore
index d184464..59cb102 100644
--- a/.gitignore
+++ b/.gitignore
@@ -9,3 +9,4 @@ composer.lock
 /tests/reports
 debug.log
 error.log
+GeoLite2-City.mmdb
\ No newline at end of file
diff --git a/composer.json b/composer.json
index d0ded8e..6c28923 100644
--- a/composer.json
+++ b/composer.json
@@ -10,7 +10,8 @@
 		"aws/aws-sdk-php": "^3.0",
 		"propel/propel": "2.0.0-alpha7",
 		"willdurand/negotiation": "~2.2.0",
-		"symfony/cache": "^3.0"
+		"symfony/cache": "^3.0",
+		"geoip2/geoip2": "^2.0.0"
 	},
 	"require-dev": {
 		"phpunit/phpunit": "~6.0",
diff --git a/phpunit.xml b/phpunit.xml
index 03d28d9..093ffb2 100644
--- a/phpunit.xml
+++ b/phpunit.xml
@@ -12,6 +12,12 @@
     </whitelist>
   </filter>
 
+	<groups>
+		<exclude>
+			<group>geoip-database</group>
+		</exclude>
+	</groups>
+
   <!--
   <logging>
       <log type="coverage-clover" target="tests/reports/logs/clover.xml"/>
diff --git a/src/Slim/Middleware/GeoIpLookup.php b/src/Slim/Middleware/GeoIpLookup.php
new file mode 100644
index 0000000..9468665
--- /dev/null
+++ b/src/Slim/Middleware/GeoIpLookup.php
@@ -0,0 +1,78 @@
+<?php
+namespace Serato\SwsApp\Slim\Middleware;
+
+use Slim\Http\Body;
+use Slim\Handlers\AbstractHandler;
+use Psr\Http\Message\RequestInterface as Request;
+use Psr\Http\Message\ResponseInterface as Response;
+use GeoIp2\Database\Reader;
+use GeoIp2\Model\City;
+use Exception;
+
+/**
+ * GeoIpLookup Middleware
+ *
+ * A middleware that exposes the results of a geo IP lookup to the RequestInterface.
+ *
+ * Two attributes are added the RequestInterface:
+ *
+ * 1. `ipAddress`       The source IP of the request. If the IP address can not be determined
+ *                      the value will be NULL.
+ * 2. `geoIpRecord`     A `GeoIp2\Model\City` record of the IP address lookup.
+ */
+class GeoIpLookup extends AbstractHandler
+{
+    const IP_ADDRESS = 'ipAddress';
+    const GEOIP_RECORD = 'geoIpRecord';
+
+    /* @var string */
+    private $geoLiteDbPath;
+
+    /**
+     * Constructs the object
+     *
+     * @param string $geoLiteDbPath     Path to a GeoLite2 database file
+     */
+    public function __construct(string $geoLiteDbPath)
+    {
+        $this->geoLiteDbPath = $geoLiteDbPath;
+    }
+
+    /**
+     * Invoke the middleware
+     *
+     * @param ServerRequestInterface $request   The most recent Request object
+     * @param ResponseInterface      $response  The most recent Response object
+     * @param Callable               $next      The next middleware to call
+     *
+     * @return ResponseInterface
+     */
+    public function __invoke(Request $request, Response $response, callable $next) : Response
+    {
+        $ip = $request->getServerParam('HTTP_X_FORWARDED_FOR', '');
+        if ($ip === '') {
+            $ip = $request->getServerParam('REMOTE_ADDR', '');
+        }
+
+        $request = $request
+                        ->withAttribute(self::IP_ADDRESS, ($ip === '' ? null : $ip))
+                        ->withAttribute(self::GEOIP_RECORD, $this->getGeoIpCityRecord($ip));
+
+        return $next($request, $response);
+    }
+
+    /**
+     * @param string    $ipAddress     IP address
+     * @return City
+     */
+    private function getGeoIpCityRecord(string $ipAddress): City
+    {
+        $reader = new Reader($this->geoLiteDbPath);
+
+        try {
+            return $reader->city($ipAddress);
+        } catch (Exception $e) {
+            return new City([]);
+        }
+    }
+}
diff --git a/tests/Slim/Middleware/GeoIpLookupTest.php b/tests/Slim/Middleware/GeoIpLookupTest.php
new file mode 100644
index 0000000..927de18
--- /dev/null
+++ b/tests/Slim/Middleware/GeoIpLookupTest.php
@@ -0,0 +1,120 @@
+<?php
+namespace Serato\SwsApp\Test\Slim\Middleware;
+
+use Serato\SwsApp\Test\TestCase;
+use Serato\SwsApp\Slim\Middleware\GeoIpLookup;
+use Serato\SwsApp\Slim\Middleware\EmptyWare;
+use Serato\Slimulator\EnvironmentBuilder;
+use Serato\Slimulator\Request;
+use Slim\Http\Response;
+
+/**
+ * Unit tests for Serato\SwsApp\Slim\Middleware\GeoIpLookup
+ *
+ * Note:
+ * These tests are tagged into the `geoip-database` group and this group of tests is not
+ * run by default. These tests require a GeoLite2 database. This database file is 50+ MB in size
+ * and it doesn't make sense to store this file in the repo.
+ *
+ * So, to run these tests:
+ *
+ *  - Get a GeoLite2 database file named `GeoLite2-City.mmdb` and place it in the root directory of this repo.
+ *  - Run the tests from a terminal with the `--group geoip-database` option.
+ */
+class GeoIpLookupTest extends TestCase
+{
+    /**
+     * @dataProvider ipAddressAttributeProvider
+     * @group geoip-database
+     */
+    public function testNoIpAddress($requestRemoteIp, $requestXForwardedIp, $requestAttributeIp)
+    {
+        $request = $this->getRequestViaMiddleware($requestRemoteIp, $requestXForwardedIp);
+
+        $this->assertEquals(
+            $requestAttributeIp,
+            $request->getAttribute(GeoIpLookup::IP_ADDRESS)
+        );
+    }
+
+    public function ipAddressAttributeProvider()
+    {
+        return [
+            ['1.1.1.1', '', '1.1.1.1'],
+            ['1.1.1.1', '2.2.2.2', '2.2.2.2'],
+            ['1.1.1.1', null, '1.1.1.1'],
+            [null, '1.1.1.1', '1.1.1.1'],
+            [null, null, null]
+        ];
+    }
+
+    /**
+     * This test is a bit fragile because the source IP addresses could (in theory) result
+     * in different geo IP records in the future. Somewhat unlikely thought.
+     *
+     * @dataProvider geoIpRecordProvider
+     * @group geoip-database
+    */
+    public function testGeoIpRecord($requestRemoteIp, $requestXForwardedIp, array $lookupData)
+    {
+        $request = $this->getRequestViaMiddleware($requestRemoteIp, $requestXForwardedIp);
+        $record = $request->getAttribute(GeoIpLookup::GEOIP_RECORD);
+        // print_r([
+        //     $record->city->name,
+        //     $record->postal->code,
+        //     $record->country->name,
+        //     $record->country->isoCode,
+        //     $record->continent->code
+        // ]);
+        $this->assertEquals($record->city->name, $lookupData[0]);
+        $this->assertEquals($record->postal->code, $lookupData[1]);
+        $this->assertEquals($record->country->name, $lookupData[2]);
+        $this->assertEquals($record->country->isoCode, $lookupData[3]);
+        $this->assertEquals($record->continent->code, $lookupData[4]);
+    }
+
+    public function geoIpRecordProvider()
+    {
+        return [
+            ['', '', ['', '', '', '', '']],
+            ['', '192.168.1.0', ['', '', '', '', '']],
+            ['203.94.44.199', '', ['', '', 'New Zealand', 'NZ', 'OC']],
+            ['', '64.0.0.0', ['', '', 'United States', 'US', 'NA']],
+            ['', '90.76.106.209', ['Blagnac', '31700', 'France', 'FR','EU']],
+            ['123.125.71.24', '', ['Beijing', '', 'China', 'CN', 'AS']],
+            ['213.205.194.98', '', ['Woking', 'GU22', 'United Kingdom', 'GB', 'EU']],
+            ['67.83.121.56', '', ['Port Washington', '11050', 'United States', 'US', 'NA']]
+        ];
+    }
+
+    /**
+     * Returns a Request instance that has been created by running a mock request
+     * through the GeoIpLookup middleware.
+     *
+     * @param mixed $remoteIp
+     * @param mixed $xForwardedIp
+     * @return Request
+     */
+    private function getRequestViaMiddleware($remoteIp = null, $xForwardedIp = null): Request
+    {
+        $middleware = new GeoIpLookup(realpath(__DIR__ . '/../../../GeoLite2-City.mmdb'));
+        $emptyMiddleware = new EmptyWare;
+
+        $env = EnvironmentBuilder::create();
+
+        if ($remoteIp !== null) {
+            $env = $env->setRemoteIpAddress($remoteIp);
+        }
+        if ($xForwardedIp !== null) {
+            $env = $env->setXForwardedForIpAddress($xForwardedIp);
+        }
+
+        $response = $middleware(
+            Request::createFromEnvironmentBuilder($env),
+            new Response,
+            $emptyMiddleware
+        );
+
+        return $emptyMiddleware->getRequestInterface();
+    }
+}