Magento – magento2: Creating custom Rest API POST method

So @user2636834 did you figure this one out already?

I remember when I was setting up a test scenario that I got the sames error(s). Seemed that I didn't have Oauth installed :O. So in short I did (running Ubuntu and following these instructions, also running into this error):

pecl install oauth

Then add extension=oauth.so to php.ini's "Dynamic Extensions" section. Then restart Apache

I tried the examples from the Magento site and got an error from the API:

"Invalid auth/bad request"

I had to add a 'Accept' => '*/*' header to the $oauthClient->fetch() call. After that it worked all just fine.

Hope you can get things running if you hadn't already.

The interface must have proper dock blocks with the existing types. But your code doesn't have a return type. For example:

<?php 
/**
 * Product type provider
 *
 * Copyright © 2015 Magento. All rights reserved.
 * See COPYING.txt for license details.
 */
namespace Magento\Catalog\Api;

/**
 * @api
 */
interface ProductTypeListInterface
{
    /**
     * Retrieve available product types
     *
     * @return \Magento\Catalog\Api\Data\ProductTypeInterface[]
     */
    public function getProductTypes();

    /**
     * Retrieve available tests
     *
     * @return \Vendor\Module\Api\Data\TestInterface[]
     */
    public function getTests();
}