diff --git a/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/FrameworkExtension.php b/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/FrameworkExtension.php
index 590d69ee9500d..442acb9dab840 100644
--- a/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/FrameworkExtension.php
+++ b/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/FrameworkExtension.php
@@ -90,6 +90,7 @@
 use Symfony\Component\Messenger\Transport\TransportInterface;
 use Symfony\Component\Mime\MimeTypeGuesserInterface;
 use Symfony\Component\Mime\MimeTypes;
+use Symfony\Component\Notifier\Bridge\Mattermost\MattermostTransportFactory;
 use Symfony\Component\Notifier\Bridge\Nexmo\NexmoTransportFactory;
 use Symfony\Component\Notifier\Bridge\Slack\SlackTransportFactory;
 use Symfony\Component\Notifier\Bridge\Telegram\TelegramTransportFactory;
@@ -1997,6 +1998,7 @@ private function registerNotifierConfiguration(array $config, ContainerBuilder $
         $classToServices = [
             SlackTransportFactory::class => 'notifier.transport_factory.slack',
             TelegramTransportFactory::class => 'notifier.transport_factory.telegram',
+            MattermostTransportFactory::class => 'notifier.transport_factory.mattermost',
             NexmoTransportFactory::class => 'notifier.transport_factory.nexmo',
             TwilioTransportFactory::class => 'notifier.transport_factory.twilio',
         ];
diff --git a/src/Symfony/Bundle/FrameworkBundle/Resources/config/notifier_transports.xml b/src/Symfony/Bundle/FrameworkBundle/Resources/config/notifier_transports.xml
index c4d9cf892adca..4625458280039 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Resources/config/notifier_transports.xml
+++ b/src/Symfony/Bundle/FrameworkBundle/Resources/config/notifier_transports.xml
@@ -18,6 +18,10 @@
             <tag name="chatter.transport_factory" />
         </service>
 
+        <service id="notifier.transport_factory.mattermost" class="Symfony\Component\Notifier\Bridge\Mattermost\MattermostTransportFactory" parent="notifier.transport_factory.abstract">
+            <tag name="chatter.transport_factory" />
+        </service>
+
         <service id="notifier.transport_factory.nexmo" class="Symfony\Component\Notifier\Bridge\Nexmo\NexmoTransportFactory" parent="notifier.transport_factory.abstract">
             <tag name="texter.transport_factory" />
         </service>
diff --git a/src/Symfony/Component/Notifier/Bridge/Mattermost/.gitattributes b/src/Symfony/Component/Notifier/Bridge/Mattermost/.gitattributes
new file mode 100644
index 0000000000000..aa02dc6518d99
--- /dev/null
+++ b/src/Symfony/Component/Notifier/Bridge/Mattermost/.gitattributes
@@ -0,0 +1,2 @@
+/Tests export-ignore
+/phpunit.xml.dist export-ignore
diff --git a/src/Symfony/Component/Notifier/Bridge/Mattermost/CHANGELOG.md b/src/Symfony/Component/Notifier/Bridge/Mattermost/CHANGELOG.md
new file mode 100644
index 0000000000000..7bd5e9a57fd19
--- /dev/null
+++ b/src/Symfony/Component/Notifier/Bridge/Mattermost/CHANGELOG.md
@@ -0,0 +1,7 @@
+CHANGELOG
+=========
+
+5.1.0
+-----
+
+ * Added the bridge
diff --git a/src/Symfony/Component/Notifier/Bridge/Mattermost/LICENSE b/src/Symfony/Component/Notifier/Bridge/Mattermost/LICENSE
new file mode 100644
index 0000000000000..5593b1d84f74a
--- /dev/null
+++ b/src/Symfony/Component/Notifier/Bridge/Mattermost/LICENSE
@@ -0,0 +1,19 @@
+Copyright (c) 2020 Fabien Potencier
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is furnished
+to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
diff --git a/src/Symfony/Component/Notifier/Bridge/Mattermost/MattermostTransport.php b/src/Symfony/Component/Notifier/Bridge/Mattermost/MattermostTransport.php
new file mode 100644
index 0000000000000..123abe834842b
--- /dev/null
+++ b/src/Symfony/Component/Notifier/Bridge/Mattermost/MattermostTransport.php
@@ -0,0 +1,78 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Notifier\Bridge\Mattermost;
+
+use Symfony\Component\Notifier\Exception\LogicException;
+use Symfony\Component\Notifier\Exception\TransportException;
+use Symfony\Component\Notifier\Message\ChatMessage;
+use Symfony\Component\Notifier\Message\MessageInterface;
+use Symfony\Component\Notifier\Transport\AbstractTransport;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
+use Symfony\Contracts\HttpClient\HttpClientInterface;
+
+/**
+ * @author Emanuele Panzeri <thepanz@gmail.com>
+ *
+ * @experimental in 5.1
+ */
+final class MattermostTransport extends AbstractTransport
+{
+    private $token;
+    private $channel;
+
+    public function __construct(string $token, string $channel, HttpClientInterface $client = null, EventDispatcherInterface $dispatcher = null)
+    {
+        $this->token = $token;
+        $this->channel = $channel;
+
+        parent::__construct($client, $dispatcher);
+    }
+
+    public function __toString(): string
+    {
+        return sprintf('mattermost://%s?channel=%s', $this->getEndpoint(), $this->channel);
+    }
+
+    public function supports(MessageInterface $message): bool
+    {
+        return $message instanceof ChatMessage;
+    }
+
+    /**
+     * @see https://api.mattermost.com
+     */
+    protected function doSend(MessageInterface $message): void
+    {
+        if (!$message instanceof ChatMessage) {
+            throw new LogicException(sprintf('The "%s" transport only supports instances of "%s" (instance of "%s" given).', __CLASS__, ChatMessage::class, \get_class($message)));
+        }
+
+        $endpoint = sprintf('https://%s/api/v4/post', $this->getEndpoint());
+
+        $options = ($opts = $message->getOptions()) ? $opts->toArray() : [];
+        $options['message'] = $message->getSubject();
+
+        if (!isset($options['channel_id'])) {
+            $options['channel_id'] = $message->getRecipientId() ?: $this->channel;
+        }
+        $response = $this->client->request('POST', $endpoint, [
+            'bearer' => $this->token,
+            'json' => array_filter($options),
+        ]);
+
+        if (200 !== $response->getStatusCode()) {
+            $result = $response->toArray(false);
+
+            throw new TransportException(sprintf('Unable to post the Mattermost message: %s (%s).', $result['message'], $result['id']), $response);
+        }
+    }
+}
diff --git a/src/Symfony/Component/Notifier/Bridge/Mattermost/MattermostTransportFactory.php b/src/Symfony/Component/Notifier/Bridge/Mattermost/MattermostTransportFactory.php
new file mode 100644
index 0000000000000..884d470ddc858
--- /dev/null
+++ b/src/Symfony/Component/Notifier/Bridge/Mattermost/MattermostTransportFactory.php
@@ -0,0 +1,45 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Notifier\Bridge\Mattermost;
+
+use Symfony\Component\Notifier\Exception\UnsupportedSchemeException;
+use Symfony\Component\Notifier\Transport\AbstractTransportFactory;
+use Symfony\Component\Notifier\Transport\Dsn;
+use Symfony\Component\Notifier\Transport\TransportInterface;
+
+/**
+ * @author Emanuele Panzeri <thepanz@gmail.com>
+ *
+ * @experimental in 5.1
+ */
+final class MattermostTransportFactory extends AbstractTransportFactory
+{
+    public function create(Dsn $dsn): TransportInterface
+    {
+        $scheme = $dsn->getScheme();
+        $token = $this->getUser($dsn);
+        $channel = $dsn->getOption('channel');
+        $host = $dsn->getHost();
+        $port = $dsn->getPort();
+
+        if ('mattermost' === $scheme) {
+            return (new MattermostTransport($token, $channel, $this->client, $this->dispatcher))->setHost($host)->setPort($port);
+        }
+
+        throw new UnsupportedSchemeException($dsn, 'mattermost', $this->getSupportedSchemes());
+    }
+
+    protected function getSupportedSchemes(): array
+    {
+        return ['mattermost'];
+    }
+}
diff --git a/src/Symfony/Component/Notifier/Bridge/Mattermost/README.md b/src/Symfony/Component/Notifier/Bridge/Mattermost/README.md
new file mode 100644
index 0000000000000..0ed0fc00a7e54
--- /dev/null
+++ b/src/Symfony/Component/Notifier/Bridge/Mattermost/README.md
@@ -0,0 +1,12 @@
+Mattermost Notifier
+===================
+
+Provides Mattermost integration for Symfony Notifier.
+
+Resources
+---------
+
+  * [Contributing](https://symfony.com/doc/current/contributing/index.html)
+  * [Report issues](https://github.com/symfony/symfony/issues) and
+    [send Pull Requests](https://github.com/symfony/symfony/pulls)
+    in the [main Symfony repository](https://github.com/symfony/symfony)
diff --git a/src/Symfony/Component/Notifier/Bridge/Mattermost/composer.json b/src/Symfony/Component/Notifier/Bridge/Mattermost/composer.json
new file mode 100644
index 0000000000000..932033c30379f
--- /dev/null
+++ b/src/Symfony/Component/Notifier/Bridge/Mattermost/composer.json
@@ -0,0 +1,35 @@
+{
+    "name": "symfony/mattermost-notifier",
+    "type": "symfony-bridge",
+    "description": "Symfony Mattermost Notifier Bridge",
+    "keywords": ["mattermost", "notifier"],
+    "homepage": "https://symfony.com",
+    "license": "MIT",
+    "authors": [
+        {
+            "name": "Emanuele Panzeri",
+            "email": "thepanz@gmail.com"
+        },
+        {
+            "name": "Symfony Community",
+            "homepage": "https://symfony.com/contributors"
+        }
+    ],
+    "require": {
+        "php": "^7.2.5",
+        "symfony/http-client": "^4.3|^5.0",
+        "symfony/notifier": "^5.0"
+    },
+    "autoload": {
+        "psr-4": { "Symfony\\Component\\Notifier\\Bridge\\Mattermost\\": "" },
+        "exclude-from-classmap": [
+            "/Tests/"
+        ]
+    },
+    "minimum-stability": "dev",
+    "extra": {
+        "branch-alias": {
+            "dev-master": "5.1-dev"
+        }
+    }
+}
diff --git a/src/Symfony/Component/Notifier/Bridge/Mattermost/phpunit.xml.dist b/src/Symfony/Component/Notifier/Bridge/Mattermost/phpunit.xml.dist
new file mode 100644
index 0000000000000..c7f35828124f0
--- /dev/null
+++ b/src/Symfony/Component/Notifier/Bridge/Mattermost/phpunit.xml.dist
@@ -0,0 +1,31 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:noNamespaceSchemaLocation="http://schema.phpunit.de/5.2/phpunit.xsd"
+         backupGlobals="false"
+         colors="true"
+         bootstrap="vendor/autoload.php"
+         failOnRisky="true"
+         failOnWarning="true"
+>
+    <php>
+        <ini name="error_reporting" value="-1" />
+    </php>
+
+    <testsuites>
+        <testsuite name="Symfony Mattermost Notifier Bridge Test Suite">
+            <directory>./Tests/</directory>
+        </testsuite>
+    </testsuites>
+
+    <filter>
+        <whitelist>
+            <directory>./</directory>
+            <exclude>
+                <directory>./Resources</directory>
+                <directory>./Tests</directory>
+                <directory>./vendor</directory>
+            </exclude>
+        </whitelist>
+    </filter>
+</phpunit>
diff --git a/src/Symfony/Component/Notifier/Bridge/Slack/SlackTransport.php b/src/Symfony/Component/Notifier/Bridge/Slack/SlackTransport.php
index 566ee7a25f608..fb18f7c913769 100644
--- a/src/Symfony/Component/Notifier/Bridge/Slack/SlackTransport.php
+++ b/src/Symfony/Component/Notifier/Bridge/Slack/SlackTransport.php
@@ -33,10 +33,10 @@ final class SlackTransport extends AbstractTransport
     private $accessToken;
     private $chatChannel;
 
-    public function __construct(string $accessToken, string $chatChannel = null, HttpClientInterface $client = null, EventDispatcherInterface $dispatcher = null)
+    public function __construct(string $accessToken, string $channel = null, HttpClientInterface $client = null, EventDispatcherInterface $dispatcher = null)
     {
         $this->accessToken = $accessToken;
-        $this->chatChannel = $chatChannel;
+        $this->chatChannel = $channel;
         $this->client = $client;
 
         parent::__construct($client, $dispatcher);
diff --git a/src/Symfony/Component/Notifier/Bridge/Telegram/TelegramTransport.php b/src/Symfony/Component/Notifier/Bridge/Telegram/TelegramTransport.php
index 7856938187499..4f9cb3b374d1c 100644
--- a/src/Symfony/Component/Notifier/Bridge/Telegram/TelegramTransport.php
+++ b/src/Symfony/Component/Notifier/Bridge/Telegram/TelegramTransport.php
@@ -38,10 +38,10 @@ final class TelegramTransport extends AbstractTransport
     private $token;
     private $chatChannel;
 
-    public function __construct(string $token, string $chatChannel = null, HttpClientInterface $client = null, EventDispatcherInterface $dispatcher = null)
+    public function __construct(string $token, string $channel = null, HttpClientInterface $client = null, EventDispatcherInterface $dispatcher = null)
     {
         $this->token = $token;
-        $this->chatChannel = $chatChannel;
+        $this->chatChannel = $channel;
         $this->client = $client;
 
         parent::__construct($client, $dispatcher);
diff --git a/src/Symfony/Component/Notifier/CHANGELOG.md b/src/Symfony/Component/Notifier/CHANGELOG.md
index ce86089d2f0ba..1501819392785 100644
--- a/src/Symfony/Component/Notifier/CHANGELOG.md
+++ b/src/Symfony/Component/Notifier/CHANGELOG.md
@@ -4,6 +4,7 @@ CHANGELOG
 5.1.0
 -----
 
+ * Added the Mattermost notifier bridge
 * [BC BREAK] The `ChatMessage::fromNotification()` method's `$recipient` and `$transport`
   arguments were removed.
 * [BC BREAK] The `EmailMessage::fromNotification()` and `SmsMessage::fromNotification()`
diff --git a/src/Symfony/Component/Notifier/Exception/UnsupportedSchemeException.php b/src/Symfony/Component/Notifier/Exception/UnsupportedSchemeException.php
index c61446339ae5c..24bdebeb17c80 100644
--- a/src/Symfony/Component/Notifier/Exception/UnsupportedSchemeException.php
+++ b/src/Symfony/Component/Notifier/Exception/UnsupportedSchemeException.php
@@ -30,6 +30,10 @@ class UnsupportedSchemeException extends LogicException
             'class' => Bridge\Telegram\TelegramTransportFactory::class,
             'package' => 'symfony/telegram-notifier',
         ],
+        'mattermost' => [
+            'class' => Bridge\Mattermost\MattermostTransportFactory::class,
+            'package' => 'symfony/mattermost-notifier',
+        ],
         'nexmo' => [
             'class' => Bridge\Nexmo\NexmoTransportFactory::class,
             'package' => 'symfony/nexmo-notifier',
diff --git a/src/Symfony/Component/Notifier/Transport.php b/src/Symfony/Component/Notifier/Transport.php
index c8e6a8ad3949c..1671fca2c964a 100644
--- a/src/Symfony/Component/Notifier/Transport.php
+++ b/src/Symfony/Component/Notifier/Transport.php
@@ -11,6 +11,7 @@
 
 namespace Symfony\Component\Notifier;
 
+use Symfony\Component\Notifier\Bridge\Mattermost\MattermostTransportFactory;
 use Symfony\Component\Notifier\Bridge\Nexmo\NexmoTransportFactory;
 use Symfony\Component\Notifier\Bridge\Slack\SlackTransportFactory;
 use Symfony\Component\Notifier\Bridge\Telegram\TelegramTransportFactory;
@@ -36,6 +37,7 @@ class Transport
     private const FACTORY_CLASSES = [
         SlackTransportFactory::class,
         TelegramTransportFactory::class,
+        MattermostTransportFactory::class,
         NexmoTransportFactory::class,
         TwilioTransportFactory::class,
     ];

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