From dee6e58227627540766b1ea80abba046987e7776 Mon Sep 17 00:00:00 2001
From: Tim Otten <totten@civicrm.org>
Date: Mon, 10 Feb 2020 17:48:50 -0800
Subject: [PATCH] (REF) CRM_Utils_Mail - Split LoggingMailer into
 FilteredPearMailer and Logger

1. Captures more context (i.e. the original driver and params)
2. Changes various property names to avoid potential for conflict with delegated properties
3. Adds `addFilter($id, $func)` so that one can move more filters in here
4. Consolidates the various references ot CIVICRM_MAIL_LOG* into one file.
---
 CRM/Utils/Mail.php                            |  43 ++-----
 CRM/Utils/Mail/FilteredPearMailer.php         | 112 ++++++++++++++++++
 CRM/Utils/Mail/Logger.php                     |  76 ++++++++++++
 CRM/Utils/Mail/LoggingMailer.php              |  67 -----------
 .../CRM/Utils/Mail/FilteredPearMailerTest.php |  54 +++++++++
 5 files changed, 255 insertions(+), 97 deletions(-)
 create mode 100644 CRM/Utils/Mail/FilteredPearMailer.php
 create mode 100644 CRM/Utils/Mail/Logger.php
 delete mode 100644 CRM/Utils/Mail/LoggingMailer.php
 create mode 100644 tests/phpunit/CRM/Utils/Mail/FilteredPearMailerTest.php

diff --git a/CRM/Utils/Mail.php b/CRM/Utils/Mail.php
index c6a982c587..02dc32cd31 100644
--- a/CRM/Utils/Mail.php
+++ b/CRM/Utils/Mail.php
@@ -123,10 +123,17 @@ class CRM_Utils_Mail {
     }
     else {
       $mailer = Mail::factory($driver, $params);
-      // Previously, CiviCRM bundled patches to change the behavior of these three classes. Use a decorator to avoid patching.
-      if ($mailer instanceof Mail_smtp || $mailer instanceof Mail_mail || $mailer instanceof  Mail_sendmail) {
-        $mailer = new CRM_Utils_Mail_LoggingMailer($mailer);
-      }
+    }
+
+    // Previously, CiviCRM bundled patches to change the behavior of 3 specific drivers. Use wrapper/filters to avoid patching.
+    $mailer = new CRM_Utils_Mail_FilteredPearMailer($driver, $params, $mailer);
+    if (in_array($driver, ['smtp', 'mail', 'sendmail'])) {
+      $mailer->addFilter('2000_log', ['CRM_Utils_Mail_Logger', 'filter']);
+      $mailer->addFilter('2100_validate', function ($mailer, &$recipients, &$headers, &$body) {
+        if (!is_array($headers)) {
+          return PEAR::raiseError('$headers must be an array');
+        }
+      });
     }
     CRM_Utils_Hook::alterMailer($mailer, $driver, $params);
     return $mailer;
@@ -330,34 +337,10 @@ class CRM_Utils_Mail {
    * @param $to
    * @param $headers
    * @param $message
+   * @deprecated
    */
   public static function logger(&$to, &$headers, &$message) {
-    if (is_array($to)) {
-      $toString = implode(', ', $to);
-      $fileName = $to[0];
-    }
-    else {
-      $toString = $fileName = $to;
-    }
-    $content = "To: " . $toString . "\n";
-    foreach ($headers as $key => $val) {
-      $content .= "$key: $val\n";
-    }
-    $content .= "\n" . $message . "\n";
-
-    if (is_numeric(CIVICRM_MAIL_LOG)) {
-      $config = CRM_Core_Config::singleton();
-      // create the directory if not there
-      $dirName = $config->configAndLogDir . 'mail' . DIRECTORY_SEPARATOR;
-      CRM_Utils_File::createDir($dirName);
-      $fileName = md5(uniqid(CRM_Utils_String::munge($fileName))) . '.txt';
-      file_put_contents($dirName . $fileName,
-        $content
-      );
-    }
-    else {
-      file_put_contents(CIVICRM_MAIL_LOG, $content, FILE_APPEND);
-    }
+    CRM_Utils_Mail_Logger::log($to, $headers, $message);
   }
 
   /**
diff --git a/CRM/Utils/Mail/FilteredPearMailer.php b/CRM/Utils/Mail/FilteredPearMailer.php
new file mode 100644
index 0000000000..1c11e23d16
--- /dev/null
+++ b/CRM/Utils/Mail/FilteredPearMailer.php
@@ -0,0 +1,112 @@
+<?php
+/*
+ +--------------------------------------------------------------------+
+ | Copyright CiviCRM LLC. All rights reserved.                        |
+ |                                                                    |
+ | This work is published under the GNU AGPLv3 license with some      |
+ | permitted exceptions and without any warranty. For full license    |
+ | and copyright information, see https://civicrm.org/licensing       |
+ +--------------------------------------------------------------------+
+ */
+
+/**
+ * The filtered-mailer is a utility to wrap an existing PEAR Mail class
+ * and apply extra filters. It is primarily intended for resolving
+ * quirks in the standard implementations.
+ *
+ * This wrapper acts a bit like a chameleon, passing-through properties
+ * from the underlying object. Consequently, internal properties are
+ * prefixed with `_` to avoid conflict.
+ *
+ * @package CRM
+ * @copyright CiviCRM LLC https://civicrm.org/licensing
+ */
+class CRM_Utils_Mail_FilteredPearMailer extends Mail {
+
+  /**
+   * @var string
+   *   Ex: 'smtp' or 'sendmail'
+   */
+  protected $_driver;
+
+  /**
+   * @var array
+   */
+  protected $_params;
+
+  /**
+   * @var Mail
+   */
+  protected $_delegate;
+
+  /**
+   * @var callable[]
+   */
+  protected $_filters = [];
+
+  /**
+   * CRM_Utils_Mail_FilteredPearMailer constructor.
+   * @param string $driver
+   * @param array $params
+   * @param Mail $mailer
+   */
+  public function __construct($driver, $params, $mailer) {
+    $this->_driver = $driver;
+    $this->_params = $params;
+    $this->_delegate = $mailer;
+  }
+
+  public function send($recipients, $headers, $body) {
+    $filterArgs = [$this, &$recipients, &$headers, &$body];
+    foreach ($this->_filters as $filter) {
+      $result = call_user_func_array($filter, $filterArgs);
+      if ($result !== NULL) {
+        return $result;
+      }
+    }
+
+    return $this->_delegate->send($recipients, $headers, $body);
+  }
+
+  /**
+   * @param string $id
+   *   Unique ID for this filter. Filters are sorted by ID.
+   *   Suggestion: '{nnnn}_{name}', where '{nnnn}' is a number.
+   *   Filters are sorted and executed in order.
+   * @param callable $func
+   *   function(FilteredPearMailer $mailer, mixed $recipients, array $headers, string $body).
+   *   The return value should generally be null/void. However, if you wish to
+   *   short-circuit execution of the filters, then return a concrete value.
+   * @return static
+   */
+  public function addFilter($id, $func) {
+    $this->_filters[$id] = $func;
+    ksort($this->_filters);
+    return $this;
+  }
+
+  /**
+   * @return string
+   *   Ex: 'smtp', 'sendmail', 'mail'.
+   */
+  public function getDriver() {
+    return $this->_driver;
+  }
+
+  public function &__get($name) {
+    return $this->_delegate->{$name};
+  }
+
+  public function __set($name, $value) {
+    return $this->_delegate->{$name} = $value;
+  }
+
+  public function __isset($name) {
+    return isset($this->_delegate->{$name});
+  }
+
+  public function __unset($name) {
+    unset($this->_delegate->{$name});
+  }
+
+}
diff --git a/CRM/Utils/Mail/Logger.php b/CRM/Utils/Mail/Logger.php
new file mode 100644
index 0000000000..453554eddd
--- /dev/null
+++ b/CRM/Utils/Mail/Logger.php
@@ -0,0 +1,76 @@
+<?php
+/*
+ +--------------------------------------------------------------------+
+ | Copyright CiviCRM LLC. All rights reserved.                        |
+ |                                                                    |
+ | This work is published under the GNU AGPLv3 license with some      |
+ | permitted exceptions and without any warranty. For full license    |
+ | and copyright information, see https://civicrm.org/licensing       |
+ +--------------------------------------------------------------------+
+ */
+
+/**
+ * An attachment to PEAR Mail which logs emails to files based on
+ * the CIVICRM_MAIL_LOG configuration.
+ *
+ * (Produced by refactoring; specifically, extracting log-related functions
+ * from CRM_Utils_Mail.)
+ *
+ * @package CRM
+ * @copyright CiviCRM LLC https://civicrm.org/licensing
+ */
+class CRM_Utils_Mail_Logger {
+
+  /**
+   * @param CRM_Utils_Mail_FilteredPearMailer $mailer
+   * @param mixed $recipients
+   * @param array $headers
+   * @param string $body
+   * @return mixed
+   *   Normally returns null/void. But if the filter process is to be
+   *   short-circuited, then returns a concrete value.
+   */
+  public static function filter($mailer, &$recipients, &$headers, &$body) {
+    if (defined('CIVICRM_MAIL_LOG')) {
+      static::log($recipients, $headers, $body);
+      if (!defined('CIVICRM_MAIL_LOG_AND_SEND') && !defined('CIVICRM_MAIL_LOG_AND SEND')) {
+        return TRUE;
+      }
+    }
+  }
+
+  /**
+   * @param $to
+   * @param $headers
+   * @param $message
+   */
+  public static function log(&$to, &$headers, &$message) {
+    if (is_array($to)) {
+      $toString = implode(', ', $to);
+      $fileName = $to[0];
+    }
+    else {
+      $toString = $fileName = $to;
+    }
+    $content = "To: " . $toString . "\n";
+    foreach ($headers as $key => $val) {
+      $content .= "$key: $val\n";
+    }
+    $content .= "\n" . $message . "\n";
+
+    if (is_numeric(CIVICRM_MAIL_LOG)) {
+      $config = CRM_Core_Config::singleton();
+      // create the directory if not there
+      $dirName = $config->configAndLogDir . 'mail' . DIRECTORY_SEPARATOR;
+      CRM_Utils_File::createDir($dirName);
+      $fileName = md5(uniqid(CRM_Utils_String::munge($fileName))) . '.txt';
+      file_put_contents($dirName . $fileName,
+        $content
+      );
+    }
+    else {
+      file_put_contents(CIVICRM_MAIL_LOG, $content, FILE_APPEND);
+    }
+  }
+
+}
diff --git a/CRM/Utils/Mail/LoggingMailer.php b/CRM/Utils/Mail/LoggingMailer.php
deleted file mode 100644
index 3f7b59b899..0000000000
--- a/CRM/Utils/Mail/LoggingMailer.php
+++ /dev/null
@@ -1,67 +0,0 @@
-<?php
-/*
- +--------------------------------------------------------------------+
- | Copyright CiviCRM LLC. All rights reserved.                        |
- |                                                                    |
- | This work is published under the GNU AGPLv3 license with some      |
- | permitted exceptions and without any warranty. For full license    |
- | and copyright information, see https://civicrm.org/licensing       |
- +--------------------------------------------------------------------+
- */
-
-/**
- * The logging-mailer is a utility to wrap an existing PEAR Mail class
- * and apply extra logging functionality.
- *
- * It replaces a set of patches which had been previously applied directly
- * to a few specific PEAR Mail classes.
- *
- * @package CRM
- * @copyright CiviCRM LLC https://civicrm.org/licensing
- */
-class CRM_Utils_Mail_LoggingMailer extends Mail {
-
-  /**
-   * @var Mail
-   */
-  protected $delegate;
-
-  /**
-   * @param Mail $delegate
-   */
-  public function __construct($delegate) {
-    $this->delegate = $delegate;
-  }
-
-  public function send($recipients, $headers, $body) {
-    if (defined('CIVICRM_MAIL_LOG')) {
-      CRM_Utils_Mail::logger($recipients, $headers, $body);
-      if (!defined('CIVICRM_MAIL_LOG_AND_SEND') && !defined('CIVICRM_MAIL_LOG_AND SEND')) {
-        return TRUE;
-      }
-    }
-
-    if (!is_array($headers)) {
-      return PEAR::raiseError('$headers must be an array');
-    }
-
-    return $this->delegate->send($recipients, $headers, $body);
-  }
-
-  public function &__get($name) {
-    return $this->delegate->{$name};
-  }
-
-  public function __set($name, $value) {
-    return $this->delegate->{$name} = $value;
-  }
-
-  public function __isset($name) {
-    return isset($this->delegate->{$name});
-  }
-
-  public function __unset($name) {
-    unset($this->delegate->{$name});
-  }
-
-}
diff --git a/tests/phpunit/CRM/Utils/Mail/FilteredPearMailerTest.php b/tests/phpunit/CRM/Utils/Mail/FilteredPearMailerTest.php
new file mode 100644
index 0000000000..56b257c9d6
--- /dev/null
+++ b/tests/phpunit/CRM/Utils/Mail/FilteredPearMailerTest.php
@@ -0,0 +1,54 @@
+<?php
+
+/**
+ * Class CRM_Utils_Mail_FilteredPearMailerTest
+ * @group headless
+ */
+class CRM_Utils_Mail_FilteredPearMailerTest extends CiviUnitTestCase {
+
+  public function testFilter() {
+    $mock = new class() extends \Mail {
+      public $buf = [];
+
+      public function send($recipients, $headers, $body) {
+        $this->buf['recipients'] = $recipients;
+        $this->buf['headers'] = $headers;
+        $this->buf['body'] = $body;
+        return 'all the fruits in the basket';
+      }
+
+    };
+
+    $fm = new CRM_Utils_Mail_FilteredPearMailer('mock', [], $mock);
+    $fm->addFilter('1000_apple', function ($mailer, &$recipients, &$headers, &$body) {
+      $body .= ' with apples!';
+    });
+    $fm->addFilter('1000_banana', function ($mailer, &$recipients, &$headers, &$body) {
+      $headers['Banana'] = 'Cavendish';
+    });
+    $r = $fm->send(['recip'], ['Subject' => 'Fruit loops'], 'body');
+
+    $this->assertEquals('Fruit loops', $mock->buf['headers']['Subject']);
+    $this->assertEquals('Cavendish', $mock->buf['headers']['Banana']);
+    $this->assertEquals('body with apples!', $mock->buf['body']);
+    $this->assertEquals('all the fruits in the basket', $r);
+  }
+
+  public function testFilter_shortCircuit() {
+    $mock = new class() extends \Mail {
+
+      public function send($recipients, $headers, $body) {
+        return 'all the fruits in the basket';
+      }
+
+    };
+
+    $fm = new CRM_Utils_Mail_FilteredPearMailer('mock', [], $mock);
+    $fm->addFilter('1000_short_circuit', function ($mailer, &$recipients, &$headers, &$body) {
+      return 'the triumph of veggies over fruits';
+    });
+    $r = $fm->send(['recip'], ['Subject' => 'Fruit loops'], 'body');
+    $this->assertEquals('the triumph of veggies over fruits', $r);
+  }
+
+}
-- 
2.25.1