guzzle http post not working with form

When I try to send a Guzzle-POST, I always get a error returned:

{"errors":[{"code":"0","status":"400","title":"Bad Request","detail":"The JSON payload is malformed."}]}

As I don't see any error,inside the data-array itself, maybe it can be a wrong header information? It is an simple POST request to shopware 6 API where I try toadd a new article.

$payload=   [
    'headers' => [
        'Content-Type' => 'application/json',
        'Accept' => 'application/json',
    ],
    'form_params' =>[
        "name" => "productname", 
        "productNumber" => "101003", 
        "stock" => 2, 
        "taxId" => "50ee15989533451095c9d7e03d9ce479", 
        "price" => [
            [
                "currencyId" => "b7d2554b0ce847cd82f3ac9bd1c0dfca", 
                "gross" => 15, 
                "net" => 10, 
                "linked" => false 
            ] 
        ] 
    ]
];


$response = $client->request('POST', 'http://shopware6.shop.de/api/product',
    $data

);

If I use Postman or RESTer or similar tools, I get a positive result, It works. So I guess I am missing sth. inside my guzzle-request (which is a copy of the origin documentation from https://shopware.stoplight.io/docs/admin-api/ZG9jOjEyMzA4NTUy-product-data )

I am using guzzle with kamermans oauth2 middleware

A simple GET-request is working too:

    $response = $client->request('GET', 'http://shopware6.shop.de/api/product/{productid}',
        [
            'headers' => [
                'Content-Type' => 'application/json',
                'Accept' => 'application/json',

            ]
        ]
    );

CodePudding user response：

You are missing the entire authentication in your request, which you might've omitted on purpose but I thought I should add it in the following example for the sake of completion.

Aside from that the cause for the bad request is using the key 'form_params', which is only used for Content-Type: multipart/form-data, instead of 'json' for the payload.

$response = $client->request('POST', 'http://localhost/api/oauth/token', [
    'headers' => [
        'Content-Type' => 'application/json',
        'Accept' => 'application/json',
    ],
    'json' => [
        'grant_type' => 'client_credentials',
        'client_id' => '...',
        'client_secret' => '...',
    ],
]);
$token = json_decode($response->getBody()->getContents(), true)['access_token'];

$payload = [
    'headers' => [
        'Content-Type' => 'application/json',
        'Accept' => 'application/json',
        'Authorization' => 'Bearer ' . $token,
    ],
    'json' => [
        'name' => 'productname', 
        'productNumber' => '101003', 
        'stock' => 2, 
        'taxId' => '...', 
        'price' => [
            [
                'currencyId' => '...', 
                'gross' => 15, 
                'net' => 10, 
                'linked' => false,
            ], 
        ], 
    ],
];

$response = $client->request('POST', 'http://localhost/api/product', $payload);