Sending Emails with Mailer (Symfony Docs) (2024)

Caution

If the username, password or host contain any character considered special in aURI (such as : / ? # [ ] @ ! $ & ' ( ) * + , ; =), you mustencode them. See RFC 3986 for the full list of reserved characters or use theurlencode function to encode them.

Using Built-in Transports

Using a 3rd Party Transport

Instead of using your own SMTP server or sendmail binary, you can send emailsvia a third-party provider:

Each library includes a Symfony Flex recipe that will adda configuration example to your .env file. For example, suppose you want touse SendGrid. First, install it:

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$ composer require symfony/sendgrid-mailer

You'll now have a new line in your .env file that you can uncomment:

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# .envMAILER_DSN=sendgrid://KEY@default

The MAILER_DSN isn't a real address: it's a convenient format thatoffloads most of the configuration work to mailer. The sendgrid schemeactivates the SendGrid provider that you just installed, which knows all abouthow to deliver messages via SendGrid. The only part you need to change is theKEY placeholder.

Each provider has different environment variables that the Mailer uses toconfigure the actual protocol, address and authentication for delivery. Somealso have options that can be configured with query parameters at the end of theMAILER_DSN - like ?region= for Amazon SES, Mailgun or Scaleway. Some providers supportsending via http, api or smtp. Symfony chooses the best availabletransport, but you can force to use one:

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# .env# force to use SMTP instead of HTTP (which is the default)MAILER_DSN=sendgrid+smtp://$SENDGRID_KEY@default

This table shows the full list of available DSN formats for each thirdparty provider:

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# .envMAILER_DSN=mailgun+https://KEY:DOMAIN@requestbin.com

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# .envMAILER_DSN=smtp://KEY:DOMAIN@smtp.eu.mailgun.org.com:25

High Availability

Symfony's mailer supports high availability via a technique called "failover"to ensure that emails are sent even if one mailer server fails.

A failover transport is configured with two or more transports and thefailover keyword:

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MAILER_DSN="failover(postmark+api://ID@default sendgrid+smtp://KEY@default)"

The failover-transport starts using the first transport and if it fails, itwill retry the same delivery with the next transports until one of them succeeds(or until all of them fail).

Load Balancing

Symfony's mailer supports load balancing via a technique called "round-robin"to distribute the mailing workload across multiple transports.

A round-robin transport is configured with two or more transports and theroundrobin keyword:

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MAILER_DSN="roundrobin(postmark+api://ID@default sendgrid+smtp://KEY@default)"

The round-robin transport starts with a randomly selected transport andthen switches to the next available transport for each subsequent email.

As with the failover transport, round-robin retries deliveries untila transport succeeds (or all fail). In contrast to the failover transport,it spreads the load across all its transports.

TLS Peer Verification

By default, SMTP transports perform TLS peer verification. This behavior isconfigurable with the verify_peer option. Although it's not recommended todisable this verification for security reasons, it can be useful while developingthe application or when using a self-signed certificate:

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$dsn = 'smtp://user:pass@smtp.example.com?verify_peer=0';

TLS Peer Fingerprint Verification

Additional fingerprint verification can be enforced with the peer_fingerprintoption. This is especially useful when a self-signed certificate is used anddisabling verify_peer is needed, but security is still desired. Fingerprintmay be specified as SHA1 or MD5 hash:

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$dsn = 'smtp://user:pass@smtp.example.com?peer_fingerprint=6A1CF3B08D175A284C30BC10DE19162307C7286E';

Disabling Automatic TLS

By default, the Mailer component will use encryption when the OpenSSL extensionis enabled and the SMTP server supports STARTTLS. This behavior can be turnedoff by calling setAutoTls(false) on the EsmtpTransport instance, or bysetting the auto_tls option to false in the DSN:

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$dsn = 'smtp://user:pass@10.0.0.25?auto_tls=false';

Overriding default SMTP authenticators

By default, SMTP transports will try to login using all authentication methodsavailable on the SMTP server, one after the other. In some cases, it may beuseful to redefine the supported authentication methods to ensure that thepreferred method will be used first.

This can be done from EsmtpTransport constructor or using thesetAuthenticators() method:

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use Symfony\Component\Mailer\Transport\Smtp\Auth\XOAuth2Authenticator;use Symfony\Component\Mailer\Transport\Smtp\EsmtpTransport;// Choose one of these two options:// Option 1: pass the authenticators to the constructor$transport = new EsmtpTransport( host: 'oauth-smtp.domain.tld', authenticators: [new XOAuth2Authenticator()]);// Option 2: call a method to redefine the authenticators$transport->setAuthenticators([new XOAuth2Authenticator()]);

Other Options

command

Command to be executed by sendmail transport:

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$dsn = 'sendmail://default?command=/usr/sbin/sendmail%20-oi%20-t'

local_domain

The domain name to use in HELO command:

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$dsn = 'smtps://smtp.example.com?local_domain=example.org'

restart_threshold

The maximum number of messages to send before re-starting the transport. Itcan be used together with restart_threshold_sleep:

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$dsn = 'smtps://smtp.example.com?restart_threshold=10&restart_threshold_sleep=1'

restart_threshold_sleep

The number of seconds to sleep between stopping and re-starting the transport.It's common to combine it with restart_threshold:

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$dsn = 'smtps://smtp.example.com?restart_threshold=10&restart_threshold_sleep=1'

ping_threshold

The minimum number of seconds between two messages required to ping the server:

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$dsn = 'smtps://smtp.example.com?ping_threshold=200'

max_per_second

The number of messages to send per second (0 to disable this limitation):

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$dsn = 'smtps://smtp.example.com?max_per_second=2'

Custom Transport Factories

If you want to support your own custom DSN (acme://...), you can create acustom transport factory. To do so, create a class that implementsTransportFactoryInterface or, ifyou prefer, extend the AbstractTransportFactoryclass to save some boilerplate code:

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// src/Mailer/AcmeTransportFactory.phpfinal class AcmeTransportFactory extends AbstractTransportFactory{ public function create(Dsn $dsn): TransportInterface { // parse the given DSN, extract data/credentials from it // and then, create and return the transport } protected function getSupportedSchemes(): array { // this supports DSN starting with `acme://` return ['acme']; }}

After creating the custom transport class, register it as a service in yourapplication and tag it with themailer.transport_factory tag.

Email Addresses

All the methods that require email addresses (from(), to(), etc.) acceptboth strings or address objects:

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// ...use Symfony\Component\Mime\Address;$email = (new Email()) // email address as a simple string ->from('fabien@example.com') // email address as an object ->from(new Address('fabien@example.com')) // defining the email address and name as an object // (email clients will display the name) ->from(new Address('fabien@example.com', 'Fabien')) // defining the email address and name as a string // (the format must match: 'Name <email@example.com>') ->from(Address::create('Fabien Potencier <fabien@example.com>')) // ...;

Use addTo(), addCc(), or addBcc() methods to add more addresses:

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$email = (new Email()) ->to('foo@example.com') ->addTo('bar@example.com') ->cc('cc@example.com') ->addCc('cc2@example.com') // ...;

Alternatively, you can pass multiple addresses to each method:

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$toAddresses = ['foo@example.com', new Address('bar@example.com')];$email = (new Email()) ->to(...$toAddresses) ->cc('cc1@example.com', 'cc2@example.com') // ...;

Message Headers

Messages include a number of header fields to describe their contents. Symfonysets all the required headers automatically, but you can set your own headerstoo. There are different types of headers (Id header, Mailbox header, Dateheader, etc.) but most of the times you'll set text headers:

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$email = (new Email()) ->getHeaders() // this non-standard header tells compliant autoresponders ("email holiday mode") to not // reply to this message because it's an automated email ->addTextHeader('X-Auto-Response-Suppress', 'OOF, DR, RN, NRN, AutoReply') // use an array if you want to add a header with multiple values // (for example in the "References" or "In-Reply-To" header) ->addIdHeader('References', ['123@example.com', '456@example.com']) // ...;

Message Contents

The text and HTML contents of the email messages can be strings (usually theresult of rendering some template) or PHP resources:

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$email = (new Email()) // ... // simple contents defined as a string ->text('Lorem ipsum...') ->html('<p>Lorem ipsum...</p>') // attach a file stream ->text(fopen('/path/to/emails/user_signup.txt', 'r')) ->html(fopen('/path/to/emails/user_signup.html', 'r'));

File Attachments

Use the addPart() method with a File to add files that exist on yourfile system:

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use Symfony\Component\Mime\Part\DataPart;use Symfony\Component\Mime\Part\File;// ...$email = (new Email()) // ... ->addPart(new DataPart(new File('/path/to/documents/terms-of-use.pdf'))) // optionally you can tell email clients to display a custom name for the file ->addPart(new DataPart(new File('/path/to/documents/privacy.pdf'), 'Privacy Policy')) // optionally you can provide an explicit MIME type (otherwise it's guessed) ->addPart(new DataPart(new File('/path/to/documents/contract.doc'), 'Contract', 'application/msword'));

Alternatively you can attach contents from a stream by passing it directly tothe DataPart:

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$email = (new Email()) // ... ->addPart(new DataPart(fopen('/path/to/documents/contract.doc', 'r')));

Embedding Images

If you want to display images inside your email, you must embed theminstead of adding them as attachments. When using Twig to render the emailcontents, as explained later in this article,the images are embedded automatically. Otherwise, you need to embed them manually.

First, use the addPart() method to add an image from afile or stream:

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$email = (new Email()) // ... // get the image contents from a PHP resource ->addPart((new DataPart(fopen('/path/to/images/logo.png', 'r'), 'logo', 'image/png'))->asInline()) // get the image contents from an existing file ->addPart((new DataPart(new File('/path/to/images/signature.gif'), 'footer-signature', 'image/gif'))->asInline());

Use the asInline() method to embed the content instead of attaching it.

The second optional argument of both methods is the image name ("Content-ID" inthe MIME standard). Its value is an arbitrary string that must be unique in eachemail message and is used later to reference the images inside the HTML contents:

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$email = (new Email()) // ... ->addPart((new DataPart(fopen('/path/to/images/logo.png', 'r'), 'logo', 'image/png'))->asInline()) ->addPart((new DataPart(new File('/path/to/images/signature.gif'), 'footer-signature', 'image/gif'))->asInline()) // reference images using the syntax 'cid:' + "image embed name" ->html('<img src="cid:logo"> ... <img src="cid:footer-signature"> ...') // use the same syntax for images included as HTML background images ->html('... <div background="cid:footer-signature"> ... </div> ...');

The actual Content-ID value present in the e-mail source will be randomly generated by Symfony.You can also use the DataPart::setContentId()method to define a custom Content-ID for the image and use it as its cid reference:

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$part = new DataPart(new File('/path/to/images/signature.gif'));// according to the spec, the Content-ID value must include at least one '@' character$part->setContentId('footer-signature@my-app');$email = (new Email()) // ... ->addPart($part->asInline()) ->html('... <img src="cid:footer-signature@my-app"> ...');

Caution

Some third-party providers don't support the usage of keywords like fromin the headers. Check out your provider's documentation before settingany global header.

Note

If your code used MailerInterface, youneed to replace it by TransportInterfaceto have the SentMessage object returned.

Note

Some mailer providers change the Message-Id when sending the email. ThegetMessageId() method from SentMessage always returns the definitiveID of the message (being the original random ID generated by Symfony or thenew ID generated by the mailer provider).

HTML Content

To define the contents of your email with Twig, use theTemplatedEmail class. This class extendsthe normal Email class but adds some new methodsfor Twig templates:

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use Symfony\Bridge\Twig\Mime\TemplatedEmail;$email = (new TemplatedEmail()) ->from('fabien@example.com') ->to(new Address('ryan@example.com')) ->subject('Thanks for signing up!') // path of the Twig template to render ->htmlTemplate('emails/signup.html.twig') // change locale used in the template, e.g. to match user's locale ->locale('de') // pass variables (name => value) to the template ->context([ 'expiration_date' => new \DateTime('+7 days'), 'username' => 'foo', ]);

Then, create the template:

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{# templates/emails/signup.html.twig #}<h1>Welcome {{ email.toName }}!</h1><p> You signed up as {{ username }} the following email:</p><p><code>{{ email.to[0].address }}</code></p><p> <a href="#">Activate your account</a> (this link is valid until {{ expiration_date|date('F jS') }})</p>

The Twig template has access to any of the parameters passed in the context()method of the TemplatedEmail class and also to a special variable calledemail, which is an instance ofWrappedTemplatedEmail.

Text Content

When the text content of a TemplatedEmail is not explicitly defined, it isautomatically generated from the HTML contents.

Symfony uses the following strategy when generating the text version of anemail:

• If an explicit HTML to text converter has been configured (seetwig.mailer.html_to_text_converter), it calls it;
• If not, and if you have league/html-to-markdown installed in yourapplication, it uses it to turn HTML into Markdown (so the text email hassome visual appeal);
• Otherwise, it applies the strip_tags PHP function to theoriginal HTML contents.

If you want to define the text content yourself, use the text() methodexplained in the previous sections or the textTemplate() method provided bythe TemplatedEmail class:

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+use Symfony\Bridge\Twig\Mime\TemplatedEmail; $email = (new TemplatedEmail()) // ... ->htmlTemplate('emails/signup.html.twig')+ ->textTemplate('emails/signup.txt.twig') // ... ;

Embedding Images

Instead of dealing with the <img src="cid: ..."> syntax explained in theprevious sections, when using Twig to render email contents you can refer toimage files as usual. First, to simplify things, define a Twig namespace calledimages that points to whatever directory your images are stored in:

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# config/packages/twig.yamltwig: # ... paths: # point this wherever your images live '%kernel.project_dir%/assets/images': images

Now, use the special email.image() Twig helper to embed the images insidethe email contents:

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{# '@images/' refers to the Twig namespace defined earlier #}<img src="{{ email.image('@images/logo.png') }}" alt="Logo"><h1>Welcome {{ email.toName }}!</h1>{# ... #}

Inlining CSS Styles

Designing the HTML contents of an email is very different from designing anormal HTML page. For starters, most email clients only support a subset of allCSS features. In addition, popular email clients like Gmail don't supportdefining styles inside <style> ... </style> sections and you must inlineall the CSS styles.

CSS inlining means that every HTML tag must define a style attribute withall its CSS styles. This can make organizing your CSS a mess. That's why Twigprovides a CssInlinerExtension that automates everything for you. Installit with:

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$ composer require twig/extra-bundle twig/cssinliner-extra

The extension is enabled automatically. To use it, wrap the entire templatewith the inline_css filter:

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{% apply inline_css %} <style> {# here, define your CSS styles as usual #} h1 { color: #333; } </style> <h1>Welcome {{ email.toName }}!</h1> {# ... #}{% endapply %}

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{% apply inline_css(source('@styles/email.css')) %} <h1>Welcome {{ username }}!</h1> {# ... #}{% endapply %}

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# config/packages/twig.yamltwig: # ... paths: # point this wherever your css files live '%kernel.project_dir%/assets/styles': styles

Rendering Markdown Content

Twig provides another extension called MarkdownExtension that lets youdefine the email contents using Markdown syntax. To use this, install theextension and a Markdown conversion library (the extension is compatible withseveral popular libraries):

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# instead of league/commonmark, you can also use erusev/parsedown or michelf/php-markdown$ composer require twig/extra-bundle twig/markdown-extra league/commonmark

The extension adds a markdown_to_html filter, which you can use to convert parts orthe entire email contents from Markdown to HTML:

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{% apply markdown_to_html %} Welcome {{ email.toName }}! =========================== You signed up to our site using the following email: `{{ email.to[0].address }}` [Activate your account]({{ url('...') }}){% endapply %}

Inky Email Templating Language

Creating beautifully designed emails that work on every email client is socomplex that there are HTML/CSS frameworks dedicated to that. One of the mostpopular frameworks is called Inky. It defines a syntax based on some HTML-liketags which are later transformed into the real HTML code sent to users:

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<!-- a simplified example of the Inky syntax --><container> <row> <columns>This is a column.</columns> </row></container>

Twig provides integration with Inky via the InkyExtension. First, installthe extension in your application:

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$ composer require twig/extra-bundle twig/inky-extra

The extension adds an inky_to_html filter, which can be used to convertparts or the entire email contents from Inky to HTML:

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{% apply inky_to_html %} <container> <row class="header"> <columns> <spacer size="16"></spacer> <h1 class="text-center">Welcome {{ email.toName }}!</h1> </columns> {# ... #} </row> </container>{% endapply %}

You can combine all filters to create complex email messages:

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{% apply inky_to_html|inline_css(source('@styles/foundation-emails.css')) %} {# ... #}{% endapply %}

This makes use of the styles Twig namespace we createdearlier. You could, for example, download the foundation-emails.css filedirectly from GitHub and save it in assets/styles.

Tip

When using OpenSSL to generate certificates, make sure to add the-addtrust emailProtection command option.

Caution

Signing and encrypting messages require their contents to be fully rendered.For example, the content of templated emails is renderedby a MessageListener.So, if you want to sign and/or encrypt such a message, you need to do it ina MessageEvent listener run after it (you need to seta negative priority to your listener).

Signing Messages

When signing a message, a cryptographic hash is generated for the entire contentof the message (including attachments). This hash is added as an attachment sothe recipient can validate the integrity of the received message. However, thecontents of the original message are still readable for mailing agents notsupporting signed messages, so you must also encrypt the message if you want tohide its contents.

You can sign messages using either S/MIME or DKIM. In both cases, thecertificate and private key must be PEM encoded, and can be either createdusing for example OpenSSL or obtained at an official Certificate Authority (CA).The email recipient must have the CA certificate in the list of trusted issuersin order to verify the signature.

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use Symfony\Component\Mime\Crypto\SMimeSigner;use Symfony\Component\Mime\Email;$email = (new Email()) ->from('hello@example.com') // ... ->html('...');$signer = new SMimeSigner('/path/to/certificate.crt', '/path/to/certificate-private-key.key');// if the private key has a passphrase, pass it as the third argument// new SMimeSigner('/path/to/certificate.crt', '/path/to/certificate-private-key.key', 'the-passphrase');$signedEmail = $signer->sign($email);// now use the Mailer component to send this $signedEmail instead of the original email

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use Symfony\Component\Mime\Crypto\DkimSigner;use Symfony\Component\Mime\Email;$email = (new Email()) ->from('hello@example.com') // ... ->html('...');// first argument: same as openssl_pkey_get_private(), either a string with the// contents of the private key or the absolute path to it (prefixed with 'file://')// second and third arguments: the domain name and "selector" used to perform a DNS lookup// (the selector is a string used to point to a specific DKIM public key record in your DNS)$signer = new DkimSigner('file:///path/to/private-key.key', 'example.com', 'sf');// if the private key has a passphrase, pass it as the fifth argument// new DkimSigner('file:///path/to/private-key.key', 'example.com', 'sf', [], 'the-passphrase');$signedEmail = $signer->sign($email);// now use the Mailer component to send this $signedEmail instead of the original email// DKIM signer provides many config options and a helper object to configure themuse Symfony\Component\Mime\Crypto\DkimOptions;$signedEmail = $signer->sign($email, (new DkimOptions()) ->bodyCanon('relaxed') ->headerCanon('relaxed') ->headersToIgnore(['Message-ID']) ->toArray());

Encrypting Messages

When encrypting a message, the entire message (including attachments) isencrypted using a certificate. Therefore, only the recipients that have thecorresponding private key can read the original message contents:

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use Symfony\Component\Mime\Crypto\SMimeEncrypter;use Symfony\Component\Mime\Email;$email = (new Email()) ->from('hello@example.com') // ... ->html('...');$encrypter = new SMimeEncrypter('/path/to/certificate.crt');$encryptedEmail = $encrypter->encrypt($email);// now use the Mailer component to send this $encryptedEmail instead of the original email

You can pass more than one certificate to the SMimeEncrypter constructorand it will select the appropriate certificate depending on the To option:

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$firstEmail = (new Email()) // ... ->to('jane@example.com');$secondEmail = (new Email()) // ... ->to('john@example.com');// the second optional argument of SMimeEncrypter defines which encryption algorithm is used// (it must be one of these constants: https://www.php.net/manual/en/openssl.ciphers.php)$encrypter = new SMimeEncrypter([ // key = email recipient; value = path to the certificate file 'jane@example.com' => '/path/to/first-certificate.crt', 'john@example.com' => '/path/to/second-certificate.crt',]);$firstEncryptedEmail = $encrypter->encrypt($firstEmail);$secondEncryptedEmail = $encrypter->encrypt($secondEmail);

Note

In cases of long-running scripts, and when Mailer uses theSmtpTransportyou may manually disconnect from the SMTP server to avoid keepingan open connection to the SMTP server in between sending emails.You can do so by using the stop() method.

Note

As it's possible for DraftEmail's to be createdwithout a To/From they cannot be sent with the mailer.

MessageEvent

Event Class: MessageEvent

MessageEvent allows to change the Mailer message and the envelope beforethe email is sent:

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use Symfony\Component\EventDispatcher\EventSubscriberInterface;use Symfony\Component\Mailer\Event\MessageEvent;use Symfony\Component\Mime\Email;public function onMessage(MessageEvent $event): void{ $message = $event->getMessage(); if (!$message instanceof Email) { return; } // do something with the message (logging, ...) // and/or add some Messenger stamps $event->addStamp(new SomeMessengerStamp());}

If you want to stop the Message from being sent, call reject() (it willalso stop the event propagation):

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use Symfony\Component\Mailer\Event\MessageEvent;public function onMessage(MessageEvent $event): void{ $event->reject();}

Execute this command to find out which listeners are registered for this eventand their priorities:

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$ php bin/console debug:event-dispatcher "Symfony\Component\Mailer\Event\MessageEvent"

SentMessageEvent

Event Class: SentMessageEvent

SentMessageEvent allows you to act on the SentMessageclass to access the original message (getOriginalMessage()) and some debugginginformation (getDebug()) such as the HTTP calls made by the HTTP transports,which is useful for debugging errors:

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use Symfony\Component\EventDispatcher\EventSubscriberInterface;use Symfony\Component\Mailer\Event\SentMessageEvent;use Symfony\Component\Mailer\SentMessage;public function onMessage(SentMessageEvent $event): void{ $message = $event->getMessage(); if (!$message instanceof SentMessage) { return; } // do something with the message}

Execute this command to find out which listeners are registered for this eventand their priorities:

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$ php bin/console debug:event-dispatcher "Symfony\Component\Mailer\Event\SentMessageEvent"

FailedMessageEvent

Event Class: FailedMessageEvent

FailedMessageEvent allows acting on the the initial message in case of a failure:

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use Symfony\Component\EventDispatcher\EventSubscriberInterface;use Symfony\Component\Mailer\Event\FailedMessageEvent;public function onMessage(FailedMessageEvent $event): void{ // e.g you can get more information on this error when sending an email $event->getError(); // do something with the message}

Execute this command to find out which listeners are registered for this eventand their priorities:

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$ php bin/console debug:event-dispatcher "Symfony\Component\Mailer\Event\FailedMessageEvent"

Enabling an Email Catcher

When developing locally, it is recommended to use an email catcher. If you haveenabled Docker support via Symfony recipes, an email catcher is automaticallyconfigured. In addition, if you are using the Symfony local web server, the mailer DSN is automatically exposed via thesymfony binary Docker integration.

Sending Test Emails

Symfony provides a command to send emails, which is useful during developmentto test if sending emails works correctly:

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# the only mandatory argument is the recipient address# (check the command help to learn about its options)$ php bin/console mailer:test someone@example.com

This command bypasses the Messenger bus, if configured, toease testing emails even when the Messenger consumer is not running.

Disabling Delivery

While developing (or testing), you may want to disable delivery of messagesentirely. You can do this by using null://null as the mailer DSN, either inyour .env configuration files or inthe mailer configuration file (e.g. in the dev or test environments):

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# config/packages/mailer.yamlwhen@dev: framework: mailer: dsn: 'null://null'

Always Send to the same Address

Instead of disabling delivery entirely, you might want to always send emails toa specific address, instead of the real address:

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# config/packages/mailer.yamlwhen@dev: framework: mailer: envelope: recipients: ['youremail@example.com']

Use the allowed_recipients option to specify exceptions to the behavior definedin the recipients option; allowing emails directed to these specific recipientsto maintain their original destination:

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# config/packages/mailer.yamlwhen@dev: framework: mailer: envelope: recipients: ['youremail@example.com'] allowed_recipients: - 'internal@example.com' # you can also use regular expression to define allowed recipients - 'internal-.*@example.(com|fr)'

With this configuration, all emails will be sent to youremail@example.com,except for those sent to internal@example.com, internal-monitoring@example.fr,etc., which will receive emails as usual.

Write a Functional Test

Symfony provides lots of built-in mailer assertionsto functionally test that an email was sent, its contents or headers, etc.They are available in test classes extendingKernelTestCase or when usingthe MailerAssertionsTrait:

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// tests/Controller/MailControllerTest.phpnamespace App\Tests\Controller;use Symfony\Bundle\FrameworkBundle\Test\WebTestCase;class MailControllerTest extends WebTestCase{ public function testMailIsSentAndContentIsOk(): void { $client = static::createClient(); $client->request('GET', '/mail/send'); $this->assertResponseIsSuccessful(); $this->assertEmailCount(1); // use assertQueuedEmailCount() when using Messenger $email = $this->getMailerMessage(); $this->assertEmailHtmlBodyContains($email, 'Welcome'); $this->assertEmailTextBodyContains($email, 'Welcome'); }}