email - laravel 5.4 embed image in mail

Question

I have just upgraded my 5.2 install of laravel to 5.3 and then to 5.4 following the official upgrading methods.

I am now trying to use one of the new features, to create a markdown formated email.

According to the documentation found at: https://laravel.com/docs/5.4/mail#view-data

To embed an inline image, use the embed method on the $message variable within your email template. Laravel automatically makes the $message variable available to all of your email templates, so you don't need to worry about passing it in manually:

However, this:

<img src="{{ $message->embed(public_path().'/img/official_logo.png') }}">

will produce the following error:

Undefined variable: message

Am I missing something? Or is there something undocumented in the upgrading guides?

Later edit:

I am calling the email function with:

Mail::to($user)->send(new WelcomeCandidate($user, $request->input('password')));

And WelcomeCandidate looks like:

<?php

namespace AppMail;

use IlluminateBusQueueable;
use IlluminateMailMailable;
use IlluminateQueueSerializesModels;
use IlluminateContractsQueueShouldQueue;

use AppModelsUser;

class WelcomeCandidate extends Mailable
{

    use Queueable, SerializesModels;

    public $user;
    public $password;

    /**
     * Create a new message instance.
     *
     * @return void
     */
    public function __construct(User $user, $password)
    {
        //
        $this->user = $user;
        $this->password = $password;
    }

    /**
     * Build the message.
     *
     * @return $this
     */
    public function build()
    {
        $this->subject('Welcome!');
        return $this->markdown('emails.welcome-candidate');
    }
}

Answer 1

It seems that the older $message->embed doesn't work nicely with Markdown emails. Like you mentioned in the comments it seems broken since 5.4

But you could just try it like this inside your markdown email:

This is your logo 
![Some option text][logo]

[logo]: {{asset('/img/official_logo.png')}} "Logo"

Like shown here: https://github.com/adam-p/markdown-here/wiki/Markdown-Cheatsheet#images

Asset function reference: https://laravel.com/docs/5.4/helpers#method-asset