How to Recieve array in request in Custom REST API in Magento 2

Question

I am working on a custom API in which user will pass the request like below in JSON.

{ "cartItem": [ { "sku": "11223344", "qty": 1 }, { "sku": "55667788", "qty": 1 } ] }

I tried to get it done like this.

interface CartItemInterface extends CustomAttributesDataInterface
{
    const CART_ITEM = 'cartItem';

    /**
    * Return list of Cart Items
    * @return \Test\TestApi\Api\Data\CartItemListInterface[]
    */
    public function getCartItem();

    /**
    * @param array $cartItemList
    */
    public function setCartItem(array $cartItemList);


}

But it gives me this error every time, after so many changes in the logic.

"message": "Property "0" does not have accessor method "get0" in class Test\TestApi\Api\Data\CartItemInterface,

Please help me with code how to fix this problem and receive this request in which multiple array of key value pairs.

Answer 1

Your API interface should not extend the class CustomAttributesDataInterface, remove extend code and check if your issue resolve by that.

Sample API Interface Code:

file: app/code/Test/TestApi/Api/CartitemManagementInterface.php

<?php
declare(strict_types=1);

namespace Test\TestApi\Api;

interface CartitemManagementInterface
{

    const CART_ITEM = 'cartItem';

    /**
    * Return list of Cart Items
    * @return \Test\TestApi\Api\Data\CartItemListInterface[]
    */
    public function getCartItem();

    /**
    * @param array $cartItemList
    */
    public function setCartItem(array $cartItemList);
}

Answer 2

For anyone else looking for answer, I have done similar stuff and here is my solution to receive 2D array in POST Request, you need Request Interface

namespace [Vendor]\[Namespace]\Api;
use [Vendor]\[Namespace]\Api\RequestInterface;

interface YourInterface
{
    /**
     * @param RequestInterface[] $cartItem
     * @return string
     */
 
    public function getPost(array $cartItem);
}

Create file [Vendor][Namespace]\Api\RequestInterface

namespace [Vendor]\[Namespace]\Api;
interface RequestInterface
{
    const QUANTITY = 'qty';
    const SKU = 'sku';

    /**
     * @return int
     */
    public function getQty(): int;

    /**
     * @param int $qty
     * @return void
     */
    public function setQty(int $qty): void;

    /**
     * @return string
     */
    public function getSku(): string;

    /**
     * @param string $sku
     * @return void
     */
    public function setSku(string $sku): void;
}

Create File [Vendor][Namespace]\Model\Api\Request

namespace [Vendor]\[Namespace]\Model\Api;

use [Vendor]\[Namespace]\Api\RequestInterface;
use Magento\Framework\DataObject;

class Request extends DataObject implements RequestInterface
{
    /**
     * @inheriDoc
     */
    public function getQty(): int
    {
        return (int)$this->getData(self::QUANTITY);
    }

    /**
     * @inheriDoc
     */
    public function setQty(int $qty): void
    {
        $this->setData(self::QUANTITY, $qty);
    }

    /**
     * @inheriDoc
     */
    public function getSku(): string
    {
        return $this->getData(self::SKU);
    }

    /**
     * @inheriDoc
     */
    public function setSku(string $sku): void
    {
        $this->setData(self::SKU, $sku);
    }

}

di.xml should be

<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd">
    <preference for="[Vendor]\[Namespace]\Api\YourInterface" type="[Vendor]\[Namespace]\Model\Api\YourModel"/>
    <preference for="[Vendor]\[Namespace]\Api\RequestInterface" type="[Vendor]\[Namespace]\Model\Api\Request"/>
</config>

This will accept request as

{"cart_item":{"0":{"sku":"SKU1"},"1":{"sku":"SKU2"}}}

Hope this helps