Laravel attach a non-physically saved file - laravel

Question

I'm trying to find a way to attach a non-physical file to an email that's being made on the spot.
I'm using the following lines in my controller:
$columns = ['line1', 'line2'];
$rows = [
['line1' => 'first', 'line2' => 'second'],
['line1' => 'first', 'line2' => 'second'],
['line1' => 'first', 'line2' => 'second'],
];
Mail::to('email#email.com')->send(new ExportMail($columns, $rows));
And the following build function in the ExportMail class:
public function build()
{
$file = fopen('php://output', 'w'); // Tried w+ too
fputcsv($file, $this->columns);
foreach ($this->rows as $row) {
fputcsv($file, $row);
}
// I tried a couple of things:
return $this->view('emails.myTestMail')
->attach($file);
return $this->view('emails.myTestMail')
->attach(fopen($file, 'r'));
return $this->view('emails.myTestMail')
->attach(fopen('php://output', 'r'));
return $this->view('emails.myTestMail')
->attach(file_get_contents($file));
return $this->view('emails.myTestMail')
->attach(file_get_contents(fopen($file, 'r')));
return $this->view('emails.myTestMail')
->attach(file_get_contents(fopen('php://output', 'r')));
}
But none if it works so I'm beginning to question if there is a way to send an email with a file that is never physically saved.

Answer 1

You can attach file data directly with the attachData method documented here:
https://laravel.com/docs/9.x/mail#raw-data-attachments
I use this regularly to attach dynamically generated PDF files, for example.
You should be able to do something like this:
return $this->view('emails.myTestMail')
->attachData($yourCsvData, "attachment.csv");
Also, I think you want to look at how you are generating your CSV data. Right now using php://output the CSV data will be sent out to the browser immediately, not stored in a variable.
There are a couple ways you can solve this, output buffering being one, or using php://temp instead, or using one of many CSV libraries (like https://csv.thephpleague.com/). I put together a fully working example for you here using php://temp:
https://laravelplayground.com/#/snippets/aa5b6594-4493-4ca4-9d12-837c102b7cc5
Expand the rawAttachments attribute on that Message on the right, and you'll see the attached CSV file.