Upload image file using slack API files.upload method - php

Question

The following code seems to work, but the Slack API saves the file a plain text.
protected function upload($file)
{
$client = $this->guzzle;
if (!$token) {
$token = env('SLACK_TOKEN');
}
$response = $client->request('POST', env('SLACK_API') . "/files.upload?token=$token", [
'form_params' => [
'name' => $file->getFilename(),
'content' => File::get($file->getRealPath()),
'filename' => $file->getFilename(),
'filetype' => 'image',
'channels' => "#_test",
]
]);
return json_decode((string)$response->getBody());
}
When I use the guzzle multipart post, I get the error: 'no_file_data' I feel like I am missing something.
Is there a way to upload images or non-text files using the files.upload method in the Slack API?

Answer 1

Almost as soon as I posted this question, I realized that I was formatting the array incorrectly on the multipart post in guzzle.
This seems to work:
$response = $this->guzzle->post(env('SLACK_API') . "/files.upload?token=$token",
['multipart' =>
[
[
'name' => 'filename',
'contents' => $file->getClientOriginalName()
],
[
'name' => 'file',
'contents' => fopen($file,'r')
],
[
'name' => 'channels',
'contents' => '#_test'
]
]
]);