I’m trying to send notification messages from my Laravel project’s PHP controller to a slack channel. I am able to get it to send with a simple string, like so:

                    Http::post(
                        config('slack_webhook'),
                        [
                            "type" => "rich_text",
                            "text" => "• User: $user_name
                            n • Email: $user_email
                            n etc
                            "
                        ]
                    );

However I’ve been trying to use Slack’s documentation to send formatted messages and I can’t get it to work. Specifically, I want to use Slack’s actual “list” styling as opposed to duping it using unicode characters and new lines like I did above. So, something like this from the docs:

{
    "type": "rich_text",
    "elements": [
        {
            "type": "rich_text_list",
            "style": "bullet",
            "elements": [
                {
                    "type": "rich_text_section",
                    "elements": [
                        {
                            "type": "text",
                            "text": "Fill out your W-2"
                        }
                    ]
                },
                {
                    "type": "rich_text_section",
                    "elements": [
                        {
                            "type": "text",
                            "text": "Enroll in "
                        },
                        {
                            "type": "link",
                            "text": "benefits",
                            "url": "https://salesforcebenefits.com"
                        }
                    ]
                },
                {
                    "type": "rich_text_section",
                    "elements": [
                        {
                            "type": "text",
                            "text": "Fill out your Slack profile, including:"
                        }
                    ]
                }
            ]
        }
    ]
},

So I’ve tried to format it for PHP but I think I’m doing something wrong.

                    $data =
                        [
                            'type' => "rich_text_list",
                            'text' => "Report1",
                            'elements' => [
                                'type' => 'rich_text_section',
                                'elements' =>
                                    [
                                        'type' => 'text',
                                        'text' => 'test section 1'
                                    ],
                                    [
                                        'type' => 'text',
                                        'text' => 'test section 1'
                                    ],

                            ]
                        ];

I also tried

                    $data =
                        [
                            'type' => "rich_text_list",
                            'text' => "Report1",
                            'elements' => [
                                'type' => 'rich_text_section',
                                'elements' =>
                                 [
                                    [
                                        'type' => 'text',
                                        'text' => 'test section 1'
                                    ],
                                    [
                                        'type' => 'text',
                                        'text' => 'test section 1'
                                    ],
                                 ]
                            ]
                        ];

I tried the above, and I’ve also tried creating a json object and using json_decode, and every time I get the following error:

local.ERROR: ErrorException: foreach() argument must be of type array|object, null given

How can I use Slack API formatting in PHP?