Mailhog, Trapmailer and gmail via symfony

Question

I got some trouble with mails generation on my Symfony app :

I use docker when I use Gmail to send emails :

MAILER_URL=gmail://[email protected]:MyPw@localhost

everything works fine

but as soon as I try to intercept these mails :

======================

Like this for mailtrap

MAILER_DSN=smtp://b3f077aeceaeb6:[email protected]:2525?encryption=tls&auth_mode=login
MAILER_URL=smtp://smtp.mailtrap.io:25&auth_mode=login&username=b3f077aeceaeb6&password=8792a1811dd8ef

or like this for mailHog

MAILER_DSN=smtp://localhost:1025
MAILER_URL="smtp://mailhog:1025?encryption=ssl&auth_mode=login&username=null&password=null"

my docker-compose.yml looks like this :

mailhog:
    container_name: mailhog
    restart: always
    image: mailhog/mailhog:latest

    ports:
        -'8025:8025'
        -'1025:1025'

Does anyone know how to see the mails displayed in mailhog? mailhog page is loaded correctly but nothing shows in it. The function sending the mail is entered, so this must be a configuration problem in my opinion

Answer 1

You need to narrow down the issue.

1. Can you send you an email via telnet or openssl (in case of STARTTLS)?

Via telnet: https://mediatemple.net/community/products/dv/204404584/sending-or-viewing-emails-using-telnet

Via OpenSSL: https://www.stevenrombauts.be/2018/12/test-smtp-with-telnet-or-openssl/

Go through the tutorial (or any on this topic) and make sure your MAILER_URL is correct (including credentials, port, etc). The last time I had some issue with email, turned out that the firewall was blocking me.

Don't be quick to rule out networking issues.

2. Once you confirmed that you can send an email via Telnet/OpenSSL:

you need to go level up and try to configure the URL in Symfony and attempt sending via swiftmailer:send command. This may reveal some odd configuration issues in Symfony and you can fix them accordingly

3. Repeat (1) and (2) but from Docker container.

Just exec into Docker and do it all over again. This may reveal some issues in Docker network configuration, which you can fix.

Please update your question with more findings and we could probably help you further...

Answer 2

Based on your post, I had a similar problem with mailhog and SwiftMailer for Symfony.

I ended up using the smtp for both MAILER_DSN and MAILER_URL as follows

MAILER_DSN=smtp://localhost:1025
MAILER_URL="smtp://localhost:1025?auth_mode=login"

As you can see the trick was to remove encryption=ssl as the mailhog does not supports it and the username=null&password=null as the software sends it as literal string "null".

Besides, in my swiftmailer.yaml and mailer.yaml I have this very simple configuration

# swiftmailer.yaml
swiftmailer:
    url: '%env(MAILER_URL)%'
    spool: { type: 'memory' }

---

# mailer.yaml
framework:
    mailer:
        dsn: '%env(MAILER_DSN)%'