feat: add a generic API request interface

lib/EasyPost/EasyPostClient.php

@@ -6,7 +6,9 @@
 use EasyPost\Exception\General\EasyPostException;
 use EasyPost\Hook\RequestHook;
 use EasyPost\Hook\ResponseHook;
+use EasyPost\Http\Requestor;
 use EasyPost\Service\AddressService;
+use EasyPost\Util\InternalUtil;
 use EasyPost\Service\ApiKeyService;
 use EasyPost\Service\BaseService;
 use EasyPost\Service\BatchService;
@@ -260,4 +262,23 @@ public function unsubscribeFromResponseHook(callable $function): void
     {
         $this->responseEvent->removeHandler($function);
     }
+
+    /**
+     * Make an API call to the EasyPost API.
+     *
+     * This public, generic interface is useful for making arbitrary API calls to the EasyPost API that
+     * are not yet supported by the client library's services. When possible, the service for your use case
+     * should be used instead as it provides a more convenient and higher-level interface depending on the endpoint.
+     *
+     * @param string $method
+     * @param string $endpoint
+     * @param mixed $params
+     * @return mixed
+     */
+    public function makeApiCall(string $method, string $endpoint, mixed $params = null): mixed
+    {
+        $response = Requestor::request($this, $method, $endpoint, $params);
+
+        return InternalUtil::convertToEasyPostObject($this, $response);
+    }
 }

test/EasyPost/EasyPostClientTest.php

@@ -8,6 +8,22 @@
 
 class EasyPostClientTest extends TestCase
 {
+    /**
+     * Setup the testing environment for this file.
+     */
+    public static function setUpBeforeClass(): void
+    {
+        TestUtil::setupVcrTests();
+    }
+
+    /**
+     * Cleanup the testing environment once finished.
+     */
+    public static function tearDownAfterClass(): void
+    {
+        TestUtil::teardownVcrTests();
+    }
+
     /**
      * Test setting and getting the API key for different EasyPostClients.
      */
@@ -66,4 +82,19 @@ public function testInvalidServiceProperty(): void
             );
         }
     }
+
+    /**
+     * Test making an API call using the generic makeApiCall method.
+     */
+    public function testMakeApiCall(): void
+    {
+        TestUtil::setupCassette('client/makeApiCall.yml');
+
+        $client = new EasyPostClient((string)getenv('EASYPOST_TEST_API_KEY'));
+
+        $response = $client->makeApiCall('get', '/addresses', ['page_size' => 1]);
+
+        $this->assertCount(1, $response['addresses']);
+        $this->assertEquals('Address', $response['addresses'][0]['object']);
+    }
 }