Clean up numerous rough edges in Mail configuration

Summary:
  - Support file attachments in Mailgun, after D8831.
  - Fix `bin/mail send-test --attach ...` flag.
  - Make `bin/mail send-test` route mail through the daemons.
  - Remove the `workerTaskID` on MetaMTAMail, which is only used (needlessly) by `bin/mail resend` and creates a huge mess elsewhere.
  - Currently, when mail fails, the daemon exits with a very generic and useless message. Instead, make `sendNow()` throw when it fails, so the real reason is surfaced. This is OK now because mail is always sent via the daemons.
  - Now that Mailgun supports attachments, document it.
  - Update a bunch of mail docs.

Test Plan:
  - Sent mail.
  - Sent mail with attachments.
  - Read documentation.

Reviewers: btrahan

Reviewed By: btrahan

Subscribers: epriestley

Differential Revision: https://secure.phabricator.com/D8832

resources/celerity/map.php

@@ -144,7 +144,7 @@ return array(
     'rsrc/css/phui/phui-status.css' => '2f562399',
     'rsrc/css/phui/phui-tag-view.css' => '295d81c4',
     'rsrc/css/phui/phui-text.css' => '23e9b4b7',
-    'rsrc/css/phui/phui-timeline-view.css' => '17905388',
+    'rsrc/css/phui/phui-timeline-view.css' => '18035042',
     'rsrc/css/phui/phui-workboard-view.css' => '84f2c272',
     'rsrc/css/phui/phui-workpanel-view.css' => '97b69459',
     'rsrc/css/sprite-actions.css' => '969ad0e5',
@@ -767,7 +767,7 @@ return array(
     'phui-status-list-view-css' => '2f562399',
     'phui-tag-view-css' => '295d81c4',
     'phui-text-css' => '23e9b4b7',
-    'phui-timeline-view-css' => '17905388',
+    'phui-timeline-view-css' => '18035042',
     'phui-workboard-view-css' => '84f2c272',
     'phui-workpanel-view-css' => '97b69459',
     'policy-css' => '957ea14c',

src/applications/metamta/PhabricatorMetaMTAWorker.php

@@ -22,14 +22,11 @@ final class PhabricatorMetaMTAWorker
       return;
     }
 
-    $id = $message->getID();
-    $message->sendNow();
-
-    // task failed if the message is still queued
-    // (instead of sent, void, or failed)
-    if ($message->getStatus() == PhabricatorMetaMTAMail::STATUS_QUEUE) {
-      throw new Exception(
-        pht('Failed to send message.'));
+    try {
+      $message->sendNow();
+    } catch (PhabricatorMetaMTAPermanentFailureException $ex) {
+      // If the mailer fails permanently, fail this task permanently.
+      throw new PhabricatorWorkerPermanentFailureException($ex->getMessage());
     }
   }
 

src/applications/metamta/adapter/PhabricatorMailImplementationMailgunAdapter.php

@@ -7,6 +7,7 @@ final class PhabricatorMailImplementationMailgunAdapter
   extends PhabricatorMailImplementationAdapter {
 
   private $params = array();
+  private $attachments = array();
 
   public function setFrom($email, $name = '') {
     $this->params['from'] = $email;
@@ -37,9 +38,13 @@ final class PhabricatorMailImplementationMailgunAdapter
   }
 
   public function addAttachment($data, $filename, $mimetype) {
-    // TODO: implement attachments. Requires changes in HTTPSFuture
-    throw new Exception(
-      "Mailgun adapter does not currently support attachments.");
+    $this->attachments[] = array(
+      'data' => $data,
+      'name' => $filename,
+      'type' => $mimetype,
+    );
+
+    return $this;
   }
 
   public function addHeader($header_name, $header_value) {
@@ -71,7 +76,7 @@ final class PhabricatorMailImplementationMailgunAdapter
     $domain = PhabricatorEnv::getEnvConfig('mailgun.domain');
     $params = array();
 
-    $params['to'] = idx($this->params, 'tos', array());
+    $params['to'] = implode(', ', idx($this->params, 'tos', array()));
     $params['subject'] = idx($this->params, 'subject');
 
     if (idx($this->params, 'is-html')) {
@@ -93,7 +98,7 @@ final class PhabricatorMailImplementationMailgunAdapter
     }
 
     if (idx($this->params, 'ccs')) {
-      $params['cc'] = $this->params['ccs'];
+      $params['cc'] = implode(', ', $this->params['ccs']);
     }
 
     foreach (idx($this->params, 'headers', array()) as $header) {
@@ -106,6 +111,14 @@ final class PhabricatorMailImplementationMailgunAdapter
       $params);
     $future->setMethod('POST');
 
+    foreach ($this->attachments as $attachment) {
+      $future->attachFileData(
+        'attachment',
+        $attachment['data'],
+        $attachment['name'],
+        $attachment['type']);
+    }
+
     list($body) = $future->resolvex();
 
     $response = json_decode($body, true);

src/applications/metamta/management/PhabricatorMailManagementResendWorkflow.php

@@ -44,15 +44,6 @@ final class PhabricatorMailManagementResendWorkflow
     }
 
     foreach ($messages as $message) {
-      if ($message->getStatus() == PhabricatorMetaMTAMail::STATUS_QUEUE) {
-        if ($message->getWorkerTaskID()) {
-          $console->writeOut(
-            "Message #%d is already queued with an assigned send task.\n",
-            $message->getID());
-          continue;
-        }
-      }
-
       $message->setStatus(PhabricatorMetaMTAMail::STATUS_QUEUE);
       $message->save();
 
@@ -60,9 +51,6 @@ final class PhabricatorMailManagementResendWorkflow
         'PhabricatorMetaMTAWorker',
         $message->getID());
 
-      $message->setWorkerTaskID($mailer_task->getID());
-      $message->save();
-
       $console->writeOut(
         "Queued message #%d for resend.\n",
         $message->getID());

src/applications/metamta/management/PhabricatorMailManagementSendTestWorkflow.php

@@ -126,8 +126,16 @@ final class PhabricatorMailManagementSendTestWorkflow
       $mail->setFrom($from->getPHID());
     }
 
+    foreach ($attach as $attachment) {
+      $data = Filesystem::readFile($attachment);
+      $name = basename($attachment);
+      $mime = Filesystem::getMimeType($attachment);
+      $file = new PhabricatorMetaMTAAttachment($data, $name, $mime);
+      $mail->addAttachment($file);
+    }
+
+    PhabricatorWorker::setRunAllTasksInProcess(true);
     $mail->save();
-    $mail->sendNow();
 
     $console->writeErr(
       "%s\n\n    phabricator/ $ ./bin/mail show-outbound --id %d\n\n",

src/applications/metamta/storage/PhabricatorMetaMTAMail.php

@@ -231,15 +231,6 @@ final class PhabricatorMetaMTAMail extends PhabricatorMetaMTADAO {
     return $this->getParam('is-error', false);
   }
 
-  public function getWorkerTaskID() {
-    return $this->getParam('worker-task');
-  }
-
-  public function setWorkerTaskID($id) {
-    $this->setParam('worker-task', $id);
-    return $this;
-  }
-
   public function getToPHIDs() {
     return $this->getParam('to', array());
   }
@@ -304,16 +295,13 @@ final class PhabricatorMetaMTAMail extends PhabricatorMetaMTADAO {
 
     $this->openTransaction();
       // Save to generate a task ID.
-      parent::save();
+      $result = parent::save();
 
       // Queue a task to send this mail.
       $mailer_task = PhabricatorWorker::scheduleTask(
         'PhabricatorMetaMTAWorker',
         $this->getID());
 
-      // Save again to update the task ID.
-      $this->setWorkerTaskID($mailer_task->getID());
-      $result = parent::save();
     $this->saveTransaction();
 
     return $result;
@@ -624,30 +612,41 @@ final class PhabricatorMetaMTAMail extends PhabricatorMetaMTADAO {
         $mailer->addCCs($add_cc);
       }
     } catch (Exception $ex) {
-      $this->setStatus(self::STATUS_FAIL);
-      $this->setMessage($ex->getMessage());
-      return $this->save();
+      $this
+        ->setStatus(self::STATUS_FAIL)
+        ->setMessage($ex->getMessage())
+        ->save();
+
+      throw $ex;
     }
 
     try {
       $ok = $mailer->send();
-      $error = null;
-    } catch (PhabricatorMetaMTAPermanentFailureException $ex) {
-      $this->setStatus(self::STATUS_FAIL);
-      $this->setMessage($ex->getMessage());
-      return $this->save();
-    } catch (Exception $ex) {
-      $ok = false;
-      $error = $ex->getMessage()."\n".$ex->getTraceAsString();
-    }
+      if (!$ok) {
+        // TODO: At some point, we should clean this up and make all mailers
+        // throw.
+        throw new Exception(
+          pht('Mail adapter encountered an unexpected, unspecified failure.'));
+      }
 
-    if (!$ok) {
-      $this->setMessage($error);
-    } else {
       $this->setStatus(self::STATUS_SENT);
-    }
+      $this->save();
 
-    return $this->save();
+      return $this;
+    } catch (PhabricatorMetaMTAPermanentFailureException $ex) {
+      $this
+        ->setStatus(self::STATUS_FAIL)
+        ->setMessage($ex->getMessage())
+        ->save();
+
+      throw $ex;
+    } catch (Exception $ex) {
+      $this
+        ->setMessage($ex->getMessage()."\n".$ex->getTraceAsString())
+        ->save();
+
+      throw $ex;
+    }
   }
 
   public static function getReadableStatus($status_code) {

src/applications/metamta/storage/__tests__/PhabricatorMetaMTAMailTestCase.php

@@ -30,7 +30,11 @@ final class PhabricatorMetaMTAMailTestCase extends PhabricatorTestCase {
 
     $mailer = new PhabricatorMailImplementationTestAdapter();
     $mailer->setFailTemporarily(true);
-    $mail->sendNow($force = true, $mailer);
+    try {
+      $mail->sendNow($force = true, $mailer);
+    } catch (Exception $ex) {
+      // Ignore.
+    }
     $this->assertEqual(
       PhabricatorMetaMTAMail::STATUS_QUEUE,
       $mail->getStatus());
@@ -42,7 +46,11 @@ final class PhabricatorMetaMTAMailTestCase extends PhabricatorTestCase {
 
     $mailer = new PhabricatorMailImplementationTestAdapter();
     $mailer->setFailPermanently(true);
-    $mail->sendNow($force = true, $mailer);
+    try {
+      $mail->sendNow($force = true, $mailer);
+    } catch (Exception $ex) {
+      // Ignore.
+    }
     $this->assertEqual(
       PhabricatorMetaMTAMail::STATUS_FAIL,
       $mail->getStatus());

src/docs/user/configuration/configuring_inbound_email.diviner

@@ -8,19 +8,24 @@ Maniphest tasks via email.
 = Preamble =
 
 This can be extremely difficult to configure correctly. This is doubly true if
-you use sendmail.
+you use a local MTA.
 
-There are basically a few approaches available:
+There are a few approaches available:
 
-  - Use SendGrid (<http://sendgrid.com/>), which is very easy but is not free.
-  - Run your own MTA, which can be quite harrowing to configure but is free.
-  - Tell the Phabricator devteam about another service you'd like support for,
-    this stuff is seriously terrible to configure on your own.
+| Receive Mail With | Setup | Cost | Notes |
+|--------|-------|------|-------|
+| Mailgun | Easy | Cheap | Recommended |
+| SendGrid | Easy | Cheap | |
+| Local MTA | Extremely Difficult | Free | Strongly discouraged! |
+
+The remainder of this document walks through configuring Phabricator to
+receive mail, and then configuring your chosen transport to deliver mail
+to Phabricator.
 
 = Configuring Phabricator =
 
-By default, Phabricator uses a "noreply@phabricator.example.com" email address
-as the 'From' (configurable with ##metamta.default-address##) and sets
+By default, Phabricator uses a `noreply@phabricator.example.com` email address
+as the 'From' (configurable with `metamta.default-address`) and sets
 'Reply-To' to the user generating the email (e.g., by making a comment), if the
 mail was generated by a user action. This means that users can reply (or
 reply-all) to email to discuss changes, but the conversation won't be recorded
@@ -36,24 +41,24 @@ over email, set these configuration keys:
     Maniphest.
 
 Set these keys to some domain which you configure according to the instructions
-below, e.g. "##phabricator.example.com##". You can set these both to the same
+below, e.g. `phabricator.example.com`. You can set these both to the same
 domain, and will generally want to. Once you set these keys, emails will use a
-'Reply-To' like "##T123+273+af310f9220ad@example.com##", which -- when
+'Reply-To' like `T123+273+af310f9220ad@example.com`, which -- when
 configured correctly, according to the instructions below -- will parse incoming
 email and allow users to interact with Maniphest tasks and Differential
 revisions over email.
 
-If you don't want phabricator to take up an entire domain (or subdomain) you
+If you don't want Phabricator to take up an entire domain (or subdomain) you
 can configure a general prefix so you can use a single mailbox to receive mail
-on. To make use of this set ##metamta.single-reply-handler-prefix## to the
-prefix of your choice, and phabricator will prepend this to the 'Reply-To'
+on. To make use of this set `metamta.single-reply-handler-prefix` to the
+prefix of your choice, and Phabricator will prepend this to the 'Reply-To'
 mail address. This works because everything up to the first (optional) '+'
 character in an email-address is considered the receiver, and everything
-after is essentially "ignored".
+after is essentially ignored.
 
-You can also set up a task creation email address, like ##bugs@example.com##,
+You can also set up a task creation email address, like `bugs@example.com`,
 which will create a Maniphest task out of any email which is set to it. To do
-this, set ##metamta.maniphest.public-create-email## in your configuration. This
+this, set `metamta.maniphest.public-create-email` in your configuration. This
 has some mild security implications, see below.
 
 = Security =
@@ -77,9 +82,9 @@ project and need to interact with users whose email accounts you have no control
 over).
 
 If you leak a bunch of reply-to addresses by accident, you can change
-##phabricator.mail-key## in your configuration to invalidate all the old hashes.
+`phabricator.mail-key` in your configuration to invalidate all the old hashes.
 
-You can also set ##metamta.public-replies##, which will change how Phabricator
+You can also set `metamta.public-replies`, which will change how Phabricator
 delivers email. Instead of sending each recipient a unique mail with a personal
 reply-to address, it will send a single email to everyone with a public reply-to
 address. This decreases security because anyone who can spoof a "From" address
@@ -88,7 +93,7 @@ practically, is a reasonable setting for many installs. The reply-to address
 will still contain a hash unique to the object it represents, so users who have
 not received an email about an object can not blindly interact with it.
 
-If you enable ##metamta.maniphest.public-create-email##, that address also uses
+If you enable `metamta.maniphest.public-create-email`, that address also uses
 the weaker "From" authentication mechanism.
 
 NOTE: Phabricator does not currently attempt to verify "From" addresses because
@@ -116,7 +121,18 @@ if your inbound email configuration is incorrect or even disabled.
 
 Run `bin/mail help <command>` for detailed help on using these commands.
 
-= SendGrid =
+= Mailgun Setup =
+
+To use Mailgun, you need a Mailgun account. You can sign up at
+<http://www.mailgun.com>. Provided you have such an account, configure it
+like this:
+
+  - Configure a mail domain according to Mailgun's instructions.
+  - Add a Mailgun route with a `catch_all()` rule which takes the action
+    `forward("https://phabricator.example.com/mail/mailgun/")`. Replace the
+    example domain with your actual domain.
+
+= SendGrid Setup =
 
 To use SendGrid, you need a SendGrid account with access to the "Parse API" for
 inbound email. Provided you have such an account, configure it like this:
@@ -142,7 +158,7 @@ That's it! If everything is working properly you should be able to send email
 to ##anything@phabricator.example.com## and it should appear in
 `bin/mail list-inbound` within a few seconds.
 
-= Installing Mailparse =
+= Local MTA: Installing Mailparse =
 
 If you're going to run your own MTA, you need to install the PECL mailparse
 extension. In theory, you can do that with:
@@ -165,7 +181,7 @@ If you get a linker error like this:
 mailparse.so. This is not the default if you have individual files in
 ##php.d/##.
 
-= MTA: Configuring Sendmail =
+= Local MTA: Configuring Sendmail =
 
 Before you can configure Sendmail, you need to install Mailparse. See the
 section "Installing Mailparse" above.
@@ -199,7 +215,7 @@ That will forward all mail to @yourdomain.com to the Phabricator processing
 script. Run ##sudo /etc/mail/make## or similar and then restart sendmail with
 ##sudo /etc/init.d/sendmail restart##.
 
-= MTA: Configuring Lamson =
+= Local MTA: Configuring Lamson =
 
 Before you can configure Lamson, you need to install Mailparse. See the section
 "Installing Mailparse" above.

src/docs/user/configuration/configuring_outbound_email.diviner

@@ -5,53 +5,60 @@ Instructions for configuring Phabricator to send mail.
 
 = Overview =
 
-Phabricator can send outbound email via several different adapters:
+Phabricator can send outbound email via several different providers, called
+"Adapters".
 
-  - by running ##sendmail## on the local host with SMTP; or
-  - by running postfix on the local host with SMTP; or
-  - by using Amazon SES (Simple Email Service); or
-  - by using SendGrid's REST API; or
-  - via a custom adapter you write; or
-  - by dropping email into a hole and not delivering it.
+| Send Mail With | Setup | Cost | Inbound | Notes |
+|---------|-------|------|---------|-------|
+| Mailgun | Easy | Cheap | Yes | Recommended |
+| Amazon SES | Easy | Cheap | No | Recommended |
+| SendGrid | Easy | Cheap | Yes | |
+| External SMTP | Medium | Varies | No | Gmail, etc. |
+| Local SMTP | Hard | Free | No | (Default) sendmail, postfix, etc |
+| Custom | Hard | Free | No | Write an adapter for some other service. |
+| Drop in a Hole | Easy | Free | No | Drops mail in a deep, dark hole. |
 
-Of these, ##sendmail## is the default but requires some configuration. SES and
-SendGrid are easier, but cost money and have some limitations. Writing a custom
-solution requires digging into the code. See below for details on how to set up
-each method.
+Of these options, sending mail via local SMTP is the default, but usually
+requires some configuration to get working. See below for details on how to
+select and configure a delivery method.
 
-Phabricator can also send outbound email in two ways:
+Overall, Mailgun and SES are much easier to set up, and using one of them is
+recommended. In particular, Mailgun will also let you set up inbound email
+easily.
 
-  - immediately, when messages are generated (default); or
-  - in the background, via a daemon.
+If you have some internal mail service you'd like to use you can also
+write a custom adapter, but this requires digging into the code.
 
-Sending mail in the background requires that you be running the Phabricator
-daemons, but can greatly improve the performance of the application if your mail
-handler is slow. For more information on using daemons, see
+Phabricator sends mail in the background, so the daemons need to be running for
+it to be able to deliver mail. You should receive setup warnings if they are
+not. For more information on using daemons, see
 @{article:Managing Daemons with phd}.
 
 = Basics =
 
 Regardless of how outbound email is delivered, you should configure these keys
-in your configuration file:
+in your configuration:
 
   - **metamta.default-address** determines where mail is sent "From" by
-    default. If your domain is ##example.org##, set this to something like
-    "##noreply@example.org##".
-  - **metamta.domain** should be set to your domain, e.g. "##example.org##".
+    default. If your domain is `example.org`, set this to something like
+    `noreply@example.org`.
+  - **metamta.domain** should be set to your domain, e.g. `example.org`.
   - **metamta.can-send-as-user** should be left as ##false## in most cases,
-    but see the documentation in ##default.conf.php## for details.
+    but see the documentation for details.
 
 = Configuring Mail Adapters =
 
-To choose how mail will be sent, change the **metamta.mail-adapter** key in
-your configuration. Possible values are:
+To choose how mail will be sent, change the `metamta.mail-adapter` key in
+your configuration. Possible values are listed in the UI:
 
+  - ##PhabricatorMailImplementationAmazonMailgunAdapter##: use Mailgun, see
+    "Adapter: Mailgun".
+  - ##PhabricatorMailImplementationAmazonSESAdapter##: use Amazon SES, see
+    "Adapter: Amazon SES".
   - ##PhabricatorMailImplementationPHPMailerLiteAdapter##: default, uses
     "sendmail", see "Adapter: Sendmail".
   - ##PhabricatorMailImplementationPHPMailerAdapter##: uses SMTP, see
     "Adapter: SMTP".
-  - ##PhabricatorMailImplementationAmazonSESAdapter##: use Amazon SES, see
-    "Adapter: Amazon SES".
   - ##PhabricatorMailImplementationSendGridAdapter##: use SendGrid, see
     "Adapter: SendGrid".
   - ##Some Custom Class You Write##: use a custom adapter you write, see
@@ -64,8 +71,8 @@ your configuration. Possible values are:
 = Adapter: Sendmail =
 
 This is the default, and selected by choosing
-##PhabricatorMailImplementationPHPMailerLiteAdapter## as the value for
-**metamta.mail-adapter**. This requires a 'sendmail' binary to be installed on
+`PhabricatorMailImplementationPHPMailerLiteAdapter` as the value for
+**metamta.mail-adapter**. This requires a `sendmail` binary to be installed on
 the system. Most MTAs (e.g., sendmail, qmail, postfix) should do this, but your
 machine may not have one installed by default. For install instructions, consult
 the documentation for your favorite MTA.
@@ -74,25 +81,35 @@ Since you'll be sending the mail yourself, you are subject to things like SPF
 rules, blackholes, and MTA configuration which are beyond the scope of this
 document. If you can already send outbound email from the command line or know
 how to configure it, this option is straightforward. If you have no idea how to
-do any of this, consider using Amazon SES.
+do any of this, strongly consider using Mailgun or Amazon SES instead.
 
 = Adapter: SMTP =
 
-For most situations of using SMTP to send email, you could actually use
-'sendmail' or 'postfix' to do it. But some SMTP server requires authentication
-and the 'sendmail' mailer doesn't work. If you want to try with postfix, for
-install instructions, consult the documentation for postfix as MTA and you
-could configure to use SMTP then.
-
-To configure Phabricator to use SMTP, set these configuration keys:
+You can use this adapter to send mail via an external SMTP server, like Gmail.
+To do this, set these configuration keys:
 
   - **metamta.mail-adapter**: set to
-    "PhabricatorMailImplementationPHPMailerAdapter".
-  - **phpmailer.mailer**: set to "smtp".
-  - **phpmailer.smtp-host**: set to hostname of your smtp server.
-  - **phpmailer.smtp-port**: set to port of your smtp server.
+    `PhabricatorMailImplementationPHPMailerAdapter`.
+  - **phpmailer.mailer**: set to `smtp`.
+  - **phpmailer.smtp-host**: set to hostname of your SMTP server.
+  - **phpmailer.smtp-port**: set to port of your SMTP server.
   - **phpmailer.smtp-user**: set to your username used for authentication.
   - **phpmailer.smtp-password**: set to your password used for authentication.
+  - **phpmailer.smtp-protocol**: set to `tls` or `ssl` if necessary. Use
+    `ssl` for Gmail.
+
+= Adapter: Mailgun =
+
+Mailgun is an email delivery service. You can learn more at
+<http://www.mailgun.com>. Mailgun isn't free, but is very easy to configure
+and works well.
+
+To use Mailgun, sign up for an account, then set these configuration keys:
+
+  - **metamta.mail-adapter**: set to
+    `PhabricatorMailImplementationMailgunAdapter`.
+  - **mailgun.api-key**: set to your Mailgun API key.
+  - **mailgun.domain**: set to your Mailgun domain.
 
 = Adapter: Amazon SES =
 
@@ -113,10 +130,6 @@ NOTE: Amazon SES **requires you to verify your "From" address**. Configure which
 then follow the Amazon SES verification process to verify it. You won't be able
 to send email until you do this!
 
-NOTE: Amazon SES is slow to accept mail (often 1-2 seconds) and application
-performance will improve greatly if you configure outbound email to send in
-the background.
-
 = Adapter: SendGrid =
 
 SendGrid is an email delivery service like Amazon SES. You can learn more at
@@ -140,9 +153,9 @@ information easily by visiting <http://sendgrid.com/developer>.
 
 You can provide a custom adapter by writing a concrete subclass of
 @{class:PhabricatorMailImplementationAdapter} and setting it as the
-**metamta.mail-adapter**.
+`metamta.mail-adapter`.
 
-TODO: This needs to be better documented once extending Phabricator is better
+TODO: This should be better documented once extending Phabricator is better
 documented.
 
 = Adapter: Disable Outbound Mail =
@@ -150,7 +163,7 @@ documented.
 You can use the @{class:PhabricatorMailImplementationTestAdapter} to completely
 disable outbound mail, if you don't want to send mail or don't want to configure
 it yet. Just set **metamta.mail-adapter** to
-"PhabricatorMailImplementationTestAdapter".
+`PhabricatorMailImplementationTestAdapter`.
 
 = Testing and Debugging Outbound Email =