mailgun / includes / mg-filter.php

mg-filter.php in Mailgun for WordPress trunk, at includes/mg-filter.php

365 lines 10.7 KB

Raw Download Zip

1	<?php
2	/**
3	* mailgun-wordpress-plugin - Sending mail from Wordpress using Mailgun
4	* Copyright (C) 2016 Mailgun, et al.
5	*
6	* This program is free software; you can redistribute it and/or modify
7	* it under the terms of the GNU General Public License as published by
8	* the Free Software Foundation; either version 2 of the License, or
9	* (at your option) any later version.
10	*
11	* This program is distributed in the hope that it will be useful,
12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14	* GNU General Public License for more details.
15	*
16	* You should have received a copy of the GNU General Public License along
17	* with this program; if not, write to the Free Software Foundation, Inc.,
18	* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
19	*
20	* @package Mailgun
21	*/
22
23	/**
24	* Tries several methods to get the MIME Content-Type of a file.
25	*
26	* @param string $filepath
27	* @param string $default_type If all methods fail, fallback to $default_type
28	*
29	* @return string Content-Type
30	*
31	* @since 1.5.4
32	*/
33	function get_mime_content_type( string $filepath, string $default_type = 'text/plain' ): string {
34	if (function_exists('mime_content_type')) {
35	return mime_content_type($filepath);
36	}
37
38	if (function_exists('finfo_file')) {
39	$fi = finfo_open(FILEINFO_MIME_TYPE);
40	$ret = finfo_file($fi, $filepath);
41	finfo_close($fi);
42
43	return $ret;
44	}
45
46	return $default_type;
47	}
48
49	/**
50	* Find the sending "From Name" with a similar process used in `wp_mail`.
51	* This operates as a filter for the from name. If the override is set,
52	* a given name will clobbered except in ONE case.
53	* If the override is not enabled this is the from name resolution order:
54	* 1. From name given by headers - {@param $from_name_header}
55	* 2. From name set in Mailgun settings
56	* 3. From `MAILGUN_FROM_NAME` constant
57	* 4. From name constructed as `<your_site_title>` or "WordPress"
58	*
59	* If the `wp_mail_from` filter is available, it is applied to the resulting
60	* `$from_addr` before being returned. The filtered result is null-tested
61	* before being returned.
62	*
63	* @param string $from_name_header
64	* @return string
65	*
66	* @since 1.5.8
67	*/
68	function mg_detect_from_name( $from_name_header = null ): string {
69	// Get options to avoid strict mode problems
70	$mg_opts = get_option('mailgun');
71	$mg_override_from = $mg_opts['override-from'] ?? null;
72	$mg_from_name = $mg_opts['from-name'] ?? null;
73
74	$from_name = null;
75
76	if ($mg_override_from && ! is_null($mg_from_name)) {
77	$from_name = $mg_from_name;
78	} elseif ( ! is_null($from_name_header)) {
79	$from_name = $from_name_header;
80	} elseif (defined('MAILGUN_FROM_NAME') && MAILGUN_FROM_NAME) {
81	$from_name = MAILGUN_FROM_NAME;
82	} elseif (empty($mg_from_name)) {
83	if (function_exists('get_current_site')) {
84	$from_name = get_current_site()->site_name;
85	} else {
86	$from_name = 'WordPress';
87	}
88	} else {
89	$from_name = $mg_from_name;
90	}
91
92	$filter_from_name = null;
93
94	if (( ! isset($mg_override_from) \|\| $mg_override_from === '0' ) && has_filter('wp_mail_from_name')) {
95	$filter_from_name = apply_filters(
96	'wp_mail_from_name',
97	$from_name
98	);
99	if ( ! empty($filter_from_name)) {
100	$from_name = $filter_from_name;
101	}
102	}
103
104	return $from_name;
105	}
106
107	/**
108	* Find the sending "From Address" with a similar process used in `wp_mail`.
109	* This operates as a filter for the from address. If the override is set,
110	* a given address will except in ONE case.
111	* If the override is not enabled this is the from address resolution order:
112	* 1. From address given by headers - {$from_addr_header}
113	* 2. From address set in Mailgun settings
114	* 3. From `MAILGUN_FROM_ADDRESS` constant
115	* 4. From address constructed as `wordpress@<your_site_domain>`
116	*
117	* If the `wp_mail_from` filter is available, it is applied to the resulting
118	* `$from_addr` before being returned. The filtered result is null-tested
119	* before being returned.
120	*
121	* If we don't have `From` input headers, use wordpress@$sitedomain
122	* Some hosts will block outgoing mail from this address if it doesn't
123	* exist but there's no easy alternative. Defaulting to admin_email
124	* might appear to be another option but some hosts may refuse to
125	* relay mail from an unknown domain.
126	*
127	* @param null $from_addr_header
128	* @return string
129	*
130	* @since 1.5.8
131	*/
132	function mg_detect_from_address( $from_addr_header = null ): string {
133	// Get options to avoid strict mode problems
134	$mg_opts = get_option('mailgun');
135	$mg_override_from = $mg_opts['override-from'] ?? null;
136	$mg_from_addr = $mg_opts['from-address'] ?? null;
137
138	if ($mg_override_from && ! is_null($mg_from_addr)) {
139	$from_addr = $mg_from_addr;
140	} elseif ( ! is_null($from_addr_header)) {
141	$from_addr = $from_addr_header;
142	} elseif (defined('MAILGUN_FROM_ADDRESS') && MAILGUN_FROM_ADDRESS) {
143	$from_addr = MAILGUN_FROM_ADDRESS;
144	} elseif (empty($mg_from_addr)) {
145	if (function_exists('get_current_site')) {
146	$sitedomain = get_current_site()->domain;
147	} else {
148	$sitedomain = isset($_SERVER['SERVER_NAME']) && !empty($_SERVER['SERVER_NAME'])
149	? $_SERVER['SERVER_NAME']
150	: wp_parse_url(site_url(), PHP_URL_HOST);
151
152	$sitedomain = strtolower(sanitize_text_field($sitedomain));
153
154	if (substr($sitedomain, 0, 4) === 'www.') {
155	$sitedomain = substr($sitedomain, 4);
156	}
157	}
158
159	$from_addr = 'wordpress@' . $sitedomain;
160	} else {
161	$from_addr = $mg_from_addr;
162	}
163
164	$filter_from_addr = null;
165	if (( ! isset($mg_override_from) \|\| $mg_override_from === '0' ) && has_filter('wp_mail_from')) {
166	$filter_from_addr = apply_filters(
167	'wp_mail_from',
168	$from_addr
169	);
170	if (!is_null($filter_from_addr)) {
171	$from_addr = $filter_from_addr;
172	}
173	}
174
175	return $from_addr;
176	}
177
178	/**
179	* Parses mail headers into an array of arrays so they can be easily modified.
180	* We have to deal with headers that may have boundaries or parts, so a single
181	* header like:
182	*
183	* From: Excited User <user@samples.mailgun.com>
184	*
185	* Will look like this in array format:
186	*
187	* array(
188	* 'from' => array(
189	* 'value' => 'Excited User <user@samples.mailgun.com>',
190	* 'boundary' => null,
191	* 'parts' => null,
192	* )
193	* )
194	*
195	* @param string\|array $headers
196	*
197	* @return array
198	*
199	* @since 1.5.8
200	*/
201	function mg_parse_headers( $headers = []): array {
202	if (empty($headers)) {
203	return [];
204	}
205
206	if ( ! is_array($headers)) {
207	$tmp = explode("\n", str_replace("\r\n", "\n", $headers));
208	} else {
209	$tmp = $headers;
210	}
211
212	$new_headers = [];
213	if ( ! empty($tmp)) {
214	$name = null;
215	$value = null;
216	$boundary = null;
217	$parts = null;
218
219	foreach ( (array) $tmp as $header) {
220	// If this header does not contain a ':', is it a fold?
221	if (false === strpos($header, ':')) {
222	// Does this header have a boundary?
223	if (false !== stripos($header, 'boundary=')) {
224	$parts = preg_split('/boundary=/i', trim($header));
225	$boundary = trim(str_replace(array( '"', '\'' ), '', $parts[1]));
226	}
227	$value .= $header;
228
229	continue;
230	}
231
232	// Explode the header
233	[$name, $value] = explode(':', trim($header), 2);
234
235	// Clean up the values
236	$name = trim($name);
237	$value = trim($value);
238
239	if ( ! isset($new_headers[ $name ])) {
240	$new_headers[ $name ] = [];
241	}
242
243	$new_headers[ $name ][] = array(
244	'value' => $value,
245	'boundary' => $boundary,
246	'parts' => $parts,
247	);
248	}
249	}
250
251	return $new_headers;
252	}
253
254	/**
255	* Takes a header array in the format produced by mg_parse_headers and
256	* dumps them down in to a submittable header format.
257	*
258	* @param array\|null $headers Headers to dump
259	*
260	* @return string String of \r\n separated headers
261	*
262	* @since 1.5.8
263	*/
264	function mg_dump_headers( ?array $headers = null ): string {
265	if ( ! is_array($headers)) {
266	return '';
267	}
268
269	$header_string = '';
270	foreach ($headers as $name => $values) {
271	$header_string .= sprintf('%s: ', $name);
272	$header_values = [];
273
274	foreach ($values as $content) {
275	// XXX - Is it actually okay to discard `parts` and `boundary`?
276	$header_values[] = $content['value'];
277	}
278
279	$header_string .= sprintf("%s\r\n", implode(', ', $header_values));
280	}
281
282	return $header_string;
283	}
284
285	/**
286	* Set the API endpoint based on the region selected.
287	* Value can be "0" if not selected, "us" or "eu"
288	*
289	* @param string $getRegion Region value set either in config or Mailgun plugin settings.
290	*
291	* @return bool\|string
292	*
293	* @since 1.5.12
294	*/
295	function mg_api_get_region( $getRegion ) {
296	switch ($getRegion) {
297	case 'us':
298	return 'https://api.mailgun.net/v3/';
299	case 'eu':
300	return 'https://api.eu.mailgun.net/v3/';
301	default:
302	return false;
303	}
304	}
305
306	/**
307	* Set the SMTP endpoint based on the region selected.
308	* Value can be "0" if not selected, "us" or "eu"
309	*
310	* @param string $getRegion Region value set either in config or Mailgun plugin settings.
311	*
312	* @return bool\|string
313	*
314	* @since 1.5.12
315	*/
316	function mg_smtp_get_region( $getRegion ) {
317	switch ($getRegion) {
318	case 'us':
319	return 'smtp.mailgun.org';
320	case 'eu':
321	return 'smtp.eu.mailgun.org';
322	default:
323	return false;
324	}
325	}
326
327	/**
328	* Override WP VIP GO filter
329	* It sets default email address to `donotreply@wordpress.com`
330	*/
331	if (( defined('WPCOM_IS_VIP_ENV') && WPCOM_IS_VIP_ENV ) \|\| ( defined('VIP_GO_ENV') && VIP_GO_ENV )) {
332
333	global $mg_from_mail;
334
335	/**
336	* @param string $from_mail
337	* @return string
338	*/
339	function mg_wp_mail_from_standard( string $from_mail ): string {
340	global $mg_from_mail;
341
342	$mg_from_mail = $from_mail;
343
344	return $from_mail;
345	}
346
347	add_filter('wp_mail_from', 'mg_wp_mail_from_standard', 0);
348
349	/**
350	* @param string $from_mail
351	* @return string
352	*/
353	function mg_wp_mail_from_new( string $from_mail ): string {
354	global $mg_from_mail;
355
356	if ( ! empty($mg_from_mail) && is_email($mg_from_mail)) {
357	return $mg_from_mail;
358	}
359
360	return $from_mail;
361	}
362
363	add_filter('wp_mail_from', 'mg_wp_mail_from_new', 2);
364	}
365