<?php
/**
* Tweetstorm block and API helper.
*
* @package automattic/jetpack
* @since 8.7.0
*/
use Automattic\Jetpack\Connection\Client;
use Automattic\Jetpack\Status;
use Twitter\Text\Regex as Twitter_Regex;
use Twitter\Text\Validator as Twitter_Validator;
/**
* Class Jetpack_Tweetstorm_Helper
*
* @since 8.7.0
*/
class Jetpack_Tweetstorm_Helper {
/**
* Blocks that can be converted to tweets.
*
* @var array {
* The key for each element must match the registered block name.
*
* @type string $type Required. The type of content this block produces. Can be one of 'break', 'embed', 'image',
* 'multiline', 'text', or 'video'.
* @type string $content_location Optional. Where the block content can be found. Can be 'html', if we need to parse
* it out of the block HTML text, 'html-attributes', if the we need to parse it out of HTML attributes
* in the block HTML, or 'block-attributes', if the content can be found in the block attributes.
* Note that these attributes need to be available when the serialised block is
* parsed using `parse_blocks()`. If it isn't set, it's assumed the block doesn't add
* any content to the Twitter thread.
* @type array $content Optional. Defines what parts of the block content need to be extracted. Behaviour can vary based on
* `$content_location`, and `$type`:
*
* - When `$content_location` is 'html', a value of `array()` or `array( 'content' )` have the same meaning:
* The entire block HTML should be used. In both cases, 'content' will be the corresponding tag in `$template`.
* - When `$content_location` is 'html', it should be formatted as `array( 'container' => 'tag' )`,
* where 'container' is the name of the corresponding RichText container in the block editor, and is also the name
* of the corresponding tag in the $template string. 'tag' is the HTML tag within the block that corresponds to this
* container. When `$type` is 'multiline', there must only be one element in the array, and tag should be set to the HTML
* tag that corresponds to each line, though the 'container' should still be the RichText container name. (Eg, in the core/list block, the tag is 'li'.)
* - When `$content_location` is 'html-attributes', the array should be formatted as `array( 'name' => array( 'tag', 'attribute') )`,
* where 'name' is the name of a particular value that different block types require, 'tag' is the name of the HTML tag where 'attribute'
* can be found, containing the value to use for 'name'. When `$type` is 'image', 'url' and 'alt' must be defined. When `$type` is 'video',
* 'url' must be defined.
* - When `$content_location` is 'block-attributes', it must be an array of block attribute names. When `$type` is 'embed', there
* only be one element, corresponding to the URL for the embed.
* @type string $template Required for 'text' and 'multiline' types, ignored for all other types. Describes how the block content will be formatted when tweeted.
* Tags should match the keys of `$content`, except for the special "{{content}}", which matches the entire HTML content of the block.
* For 'multiline' types, the template will be repeated for every line in the block.
* @type boolean $force_new Required. Whether or not a new tweet should be started when this block is encountered.
* @type boolean $force_finished Required. Whether or not a new tweet should be started after this block is finished.
* }
*/
private static $supported_blocks = array(
'core/embed' => array(
'type' => 'embed',
'content_location' => 'block-attributes',
'content' => array( 'url' ),
'force_new' => false,
'force_finished' => true,
),
'core/gallery' => array(
'type' => 'image',
'content_location' => 'html-attributes',
'content' => array(
'url' => array( 'img', 'src' ),
'alt' => array( 'img', 'alt' ),
),
'force_new' => false,
'force_finished' => true,
),
'core/heading' => array(
'type' => 'text',
'content_location' => 'html',
'content' => array(),
'template' => '{{content}}',
'force_new' => true,
'force_finished' => false,
),
'core/image' => array(
'type' => 'image',
'content_location' => 'html-attributes',
'content' => array(
'url' => array( 'img', 'src' ),
'alt' => array( 'img', 'alt' ),
),
'force_new' => false,
'force_finished' => true,
),
'core/list' => array(
'type' => 'multiline',
'content_location' => 'html',
// It looks a little weird to use the 'values' key for a single line,
// but 'values' is the name of the RichText content area.
'content' => array(
'values' => 'li',
),
'template' => '- {{values}}',
'force_new' => false,
'force_finished' => false,
),
'core/paragraph' => array(
'type' => 'text',
'content_location' => 'html',
'content' => array(),
'template' => '{{content}}',
'force_new' => false,
'force_finished' => false,
),
'core/quote' => array(
'type' => 'text',
'content_location' => 'html',
// The quote content will always be inside <p> tags.
'content' => array(
'value' => 'p',
'citation' => 'cite',
),
'template' => '“{{value}}” – {{citation}}',
'force_new' => false,
'force_finished' => false,
),
'core/separator' => array(
'type' => 'break',
'force_new' => false,
'force_finished' => true,
),
'core/spacer' => array(
'type' => 'break',
'force_new' => false,
'force_finished' => true,
),
'core/verse' => array(
'type' => 'text',
'content_location' => 'html',
'content' => array(),
'template' => '{{content}}',
'force_new' => false,
'force_finished' => false,
),
'core/video' => array(
'type' => 'video',
'content_location' => 'html-attributes',
'content' => array(
'url' => array( 'video', 'src' ),
),
'force_new' => false,
'force_finished' => true,
),
'jetpack/gif' => array(
'type' => 'embed',
'content_location' => 'block-attributes',
'content' => array( 'giphyUrl' ),
'force_new' => false,
'force_finished' => true,
),
);
/**
* A cache of _wp_emoji_list( 'entities' ), after being run through html_entity_decode().
*
* Initialised in ::is_valid_tweet().
*
* @var array
*/
private static $emoji_list = array();
/**
* Special line separator character, for multiline text.
*
* @var string
*/
private static $line_separator = "\xE2\x80\xA8";
/**
* Special inline placeholder character, for inline tags that change content length in the RichText..
*
* @var string
*/
private static $inline_placeholder = "\xE2\x81\xA3";
/**
* URLs always take up a fixed length from the text limit.
*
* @var int
*/
private static $characters_per_url = 24;
/**
* Every media attachment takes up some space from the text limit.
*
* @var int
*/
private static $characters_per_media = 24;
/**
* An array to store all the tweets in.
*
* @var array
*/
private static $tweets = array();
/**
* While we're caching everything, we want to keep track of the URLs we're adding.
*
* @var array
*/
private static $urls = array();
/**
* Checks if a given request is allowed to gather tweets.
*
* @param WP_REST_Request $request Full details about the request.
*
* @return true|WP_Error True if the request has access to gather tweets from a thread, WP_Error object otherwise.
*/
public static function permissions_check( $request ) { // phpcs:ignore Generic.CodeAnalysis.UnusedFunctionParameter, VariableAnalysis.CodeAnalysis.VariableAnalysis.UnusedVariable
$blog_id = get_current_blog_id();
/*
* User hitting the endpoint hosted on their Jetpack site, from their Jetpack site,
* or hitting the endpoint hosted on WPCOM, from their WPCOM site.
*/
if ( current_user_can_for_blog( $blog_id, 'edit_posts' ) ) {
return true;
}
// Jetpack hitting the endpoint hosted on WPCOM, from a Jetpack site with a blog token.
if ( defined( 'IS_WPCOM' ) && IS_WPCOM ) {
if ( is_jetpack_site( $blog_id ) ) {
if ( ! class_exists( 'WPCOM_REST_API_V2_Endpoint_Jetpack_Auth' ) ) {
require_once dirname( __DIR__ ) . '/rest-api-plugins/endpoints/jetpack-auth.php';
}
$jp_auth_endpoint = new WPCOM_REST_API_V2_Endpoint_Jetpack_Auth();
if ( true === $jp_auth_endpoint->is_jetpack_authorized_for_site() ) {
return true;
}
}
}
return new WP_Error(
'rest_forbidden',
__( 'Sorry, you are not allowed to use tweetstorm endpoints on this site.', 'jetpack' ),
array( 'status' => rest_authorization_required_code() )
);
}
/**
* Gather the Tweetstorm.
*
* @param string $url The tweet URL to gather from.
* @return mixed
*/
public static function gather( $url ) {
if ( ( new Status() )->is_offline_mode() ) {
return new WP_Error(
'dev_mode',
__( 'Tweet unrolling is not available in offline mode.', 'jetpack' )
);
}
$site_id = self::get_site_id();
if ( is_wp_error( $site_id ) ) {
return $site_id;
}
if ( defined( 'IS_WPCOM' ) && IS_WPCOM ) {
if ( ! class_exists( 'WPCOM_Gather_Tweetstorm' ) ) {
\jetpack_require_lib( 'gather-tweetstorm' );
}
return WPCOM_Gather_Tweetstorm::gather( $url );
}
$response = Client::wpcom_json_api_request_as_blog(
sprintf( '/sites/%d/tweetstorm/gather?url=%s', $site_id, rawurlencode( $url ) ),
2,
array( 'headers' => array( 'content-type' => 'application/json' ) ),
null,
'wpcom'
);
if ( is_wp_error( $response ) ) {
return $response;
}
$data = json_decode( wp_remote_retrieve_body( $response ) );
if ( wp_remote_retrieve_response_code( $response ) >= 400 ) {
return new WP_Error( $data->code, $data->message, $data->data );
}
return $data;
}
/**
* Parse blocks into an array of tweets.
*
* @param array $blocks {
* An array of blocks, with optional editor-specific information, that need to be parsed into tweets.
*
* @type array $block A single block, in the form produce by parse_blocks().
* @type array $attributes Optional. A list of block attributes and their values from the block editor.
* @type string $clientId Optional. The clientId of this block in the block editor.
* }
* @return array An array of tweets.
*/
public static function parse( $blocks ) {
// Reset the tweets array.
self::$tweets = array();
$blocks = self::extract_blocks( $blocks );
if ( empty( $blocks ) ) {
return array();
}
// Initialise the tweets array with an empty tweet, so we don't need to check
// if we're creating the first tweet while processing blocks.
self::start_new_tweet();
foreach ( $blocks as $block ) {
$block_def = self::get_block_definition( $block['name'] );
// Grab the most recent tweet.
$current_tweet = self::get_current_tweet();
// Break blocks have no content to add, so we can skip the rest of this loop.
if ( 'break' === $block_def['type'] ) {
self::save_current_tweet( $current_tweet, $block );
continue;
}
// Check if we need to start a new tweet.
if ( $current_tweet['finished'] || $block_def['force_new'] ) {
self::start_new_tweet();
}
// Process the block.
self::add_text_to_tweets( $block );
self::add_media_to_tweets( $block );
self::add_tweet_to_tweets( $block );
self::add_embed_to_tweets( $block );
}
return self::clean_return_tweets();
}
/**
* If the passed block name is supported, return the block definition.
*
* @param string $block_name The registered block name.
* @return array|null The block definition, if it's supported.
*/
private static function get_block_definition( $block_name ) {
if ( isset( self::$supported_blocks[ $block_name ] ) ) {
return self::$supported_blocks[ $block_name ];
}
return null;
}
/**
* If the block has any text, process it, and add it to the tweet list.
*
* @param array $block The block to process.
*/
private static function add_text_to_tweets( $block ) {
// This is a text block, is there any text?
if ( 0 === strlen( $block['text'] ) ) {
return;
}
$block_def = self::get_block_definition( $block['name'] );
// Grab the most recent tweet, so we can append to that if we can.
$current_tweet = self::get_current_tweet();
// If the entire block can't be fit in this tweet, we need to start a new tweet.
if ( $current_tweet['changed'] && ! self::is_valid_tweet( trim( $current_tweet['text'] ) . "\n\n{$block['text']}" ) ) {
self::start_new_tweet();
}
// Multiline blocks prioritise splitting by line, but are otherwise identical to
// normal text blocks. This means we can treat normal text blocks as being
// "multiline", but with a single line.
if ( 'multiline' === $block_def['type'] ) {
$lines = explode( self::$line_separator, $block['text'] );
} else {
$lines = array( $block['text'] );
}
$line_total = count( $lines );
// Keep track of how many characters from this block we've allocated to tweets.
$current_character_count = 0;
for ( $line_count = 0; $line_count < $line_total; $line_count++ ) {
$line_text = $lines[ $line_count ];
// Make sure we have the most recent tweet at the start of every loop.
$current_tweet = self::get_current_tweet();
if ( $current_tweet['changed'] ) {
// When it's the first line, add an extra blank line to seperate
// the tweet text from that of the previous block.
$separator = "\n\n";
if ( $line_count > 0 ) {
$separator = "\n";
}
// Is this line short enough to append to the current tweet?
if ( self::is_valid_tweet( trim( $current_tweet['text'] ) . "$separator$line_text" ) ) {
// Don't trim the text yet, as we may need it for boundary calculations.
$current_tweet['text'] = $current_tweet['text'] . "$separator$line_text";
self::save_current_tweet( $current_tweet, $block );
continue;
}
// This line is too long, and lines *must* be split to a new tweet if they don't fit
// into the current tweet. If this isn't the first line, record where we split the block.
if ( $line_count > 0 ) {
// Increment by 1 to allow for the \n between lines to be counted by ::get_boundary().
$current_character_count += strlen( $current_tweet['text'] ) + 1;
$current_tweet['boundary'] = self::get_boundary( $block, $current_character_count );
self::save_current_tweet( $current_tweet );
}
// Start a new tweet.
$current_tweet = self::start_new_tweet();
}
// Since we're now at the start of a new tweet, is this line short enough to be a tweet by itself?
if ( self::is_valid_tweet( $line_text ) ) {
$current_tweet['text'] = $line_text;
self::save_current_tweet( $current_tweet, $block );
continue;
}
// The line is too long for a single tweet, so split it by sentences, or linebreaks.
$sentences = preg_split( '/(?|(?<!\.\.\.)(?<=[.?!]|\.\)|\.["\'])(\s+)(?=[\p{L}\'"\(])|(\n+))/u', $line_text, -1, PREG_SPLIT_DELIM_CAPTURE );
$sentence_total = count( $sentences );
// preg_split() puts the blank space between sentences into a seperate entry in the result,
// so we need to step through the result array by two, and append the blank space when needed.
for ( $sentence_count = 0; $sentence_count < $sentence_total; $sentence_count += 2 ) {
$current_sentence = $sentences[ $sentence_count ];
if ( isset( $sentences[ $sentence_count + 1 ] ) ) {
$current_sentence .= $sentences[ $sentence_count + 1 ];
}
// Make sure we have the most recent tweet.
$current_tweet = self::get_current_tweet();
// After the first sentence, we can try and append sentences to the previous sentence.
if ( $current_tweet['changed'] && $sentence_count > 0 ) {
// Is this sentence short enough for appending to the current tweet?
if ( self::is_valid_tweet( $current_tweet['text'] . rtrim( $current_sentence ) ) ) {
$current_tweet['text'] .= $current_sentence;
self::save_current_tweet( $current_tweet, $block );
continue;
}
}
// Will this sentence fit in its own tweet?
if ( self::is_valid_tweet( trim( $current_sentence ) ) ) {
if ( $current_tweet['changed'] ) {
// If we're already in the middle of a block, record the boundary
// before creating a new tweet.
if ( $line_count > 0 || $sentence_count > 0 ) {
$current_character_count += strlen( $current_tweet['text'] );
$current_tweet['boundary'] = self::get_boundary( $block, $current_character_count );
self::save_current_tweet( $current_tweet );
}
$current_tweet = self::start_new_tweet();
}
$current_tweet['text'] = $current_sentence;
self::save_current_tweet( $current_tweet, $block );
continue;
}
// This long sentence will start the next tweet that this block is going
// to be turned into, so we need to record the boundary and start a new tweet.
if ( $current_tweet['changed'] ) {
$current_character_count += strlen( $current_tweet['text'] );
$current_tweet['boundary'] = self::get_boundary( $block, $current_character_count );
self::save_current_tweet( $current_tweet );
$current_tweet = self::start_new_tweet();
}
// Split the long sentence into words.
$words = preg_split( '/(\p{Z})/u', $current_sentence, -1, PREG_SPLIT_DELIM_CAPTURE );
$word_total = count( $words );
for ( $word_count = 0; $word_count < $word_total; $word_count += 2 ) {
// Make sure we have the most recent tweet.
$current_tweet = self::get_current_tweet();
// If we're on a new tweet, we don't want to add a space at the start.
if ( ! $current_tweet['changed'] ) {
$current_tweet['text'] = $words[ $word_count ];
self::save_current_tweet( $current_tweet, $block );
continue;
}
// Can we add this word to the current tweet?
if ( self::is_valid_tweet( "{$current_tweet['text']} {$words[ $word_count ]}…" ) ) {
$space = isset( $words[ $word_count - 1 ] ) ? $words[ $word_count - 1 ] : ' ';
$current_tweet['text'] .= $space . $words[ $word_count ];
self::save_current_tweet( $current_tweet, $block );
continue;
}
// Add one for the space character that we won't include in the tweet text.
$current_character_count += strlen( $current_tweet['text'] ) + 1;
// We're starting a new tweet with this word. Append ellipsis to
// the current tweet, then move on.
$current_tweet['text'] .= '…';
$current_tweet['boundary'] = self::get_boundary( $block, $current_character_count );
self::save_current_tweet( $current_tweet );
$current_tweet = self::start_new_tweet();
// If this is the second tweet created by the split sentence, it'll start
// with ellipsis, which we don't want to count, but we do want to count the space
// that was replaced by this ellipsis.
$current_tweet['text'] = "…{$words[ $word_count ]}";
$current_character_count -= strlen( '…' );
self::save_current_tweet( $current_tweet, $block );
}
}
}
}
/**
* Check if the block has any media to add, and add it.
*
* @param array $block The block to process.
*/
private static function add_media_to_tweets( $block ) {
// There's some media to attach!
$media_count = count( $block['media'] );
if ( 0 === $media_count ) {
return;
}
$current_tweet = self::get_current_tweet();
// We can only attach media to the previous tweet if the previous tweet
// doesn't already have media.
if ( count( $current_tweet['media'] ) > 0 ) {
$current_tweet = self::start_new_tweet();
}
// Would adding this media make the text of the previous tweet too long?
if ( ! self::is_valid_tweet( $current_tweet['text'], $media_count * self::$characters_per_media ) ) {
$current_tweet = self::start_new_tweet();
}
$media = array_values(
array_filter(
$block['media'],
function ( $single ) {
// Only images and videos can be uploaded.
if ( 0 === strpos( $single['type'], 'image/' ) || 0 === strpos( $single['type'], 'video/' ) ) {
return true;
}
return false;
}
)
);
if ( count( $media ) > 0 ) {
if ( 0 === strpos( $media[0]['type'], 'video/' ) || 'image/gif' === $media[0]['type'] ) {
// We can only attach a single video or GIF.
$current_tweet['media'] = array_slice( $media, 0, 1 );
} else {
// Since a GIF or video isn't the first element, we can remove all of them from the array.
$filtered_media = array_values(
array_filter(
$media,
function ( $single ) {
if ( 0 === strpos( $single['type'], 'video/' ) || 'image/gif' === $single['type'] ) {
return false;
}
return true;
}
)
);
// We can only add the first four images found to the tweet.
$current_tweet['media'] = array_slice( $filtered_media, 0, 4 );
}
self::save_current_tweet( $current_tweet, $block );
}
}
/**
* Check if the block has a tweet that we can attach to the current tweet as a quote, and add it.
*
* @param array $block The block to process.
*/
private static function add_tweet_to_tweets( $block ) {
if ( 0 === strlen( $block['tweet'] ) ) {
return;
}
$current_tweet = self::get_current_tweet();
// We can only attach a tweet to the previous tweet if the previous tweet
// doesn't already have a tweet quoted.
if ( strlen( $current_tweet['tweet'] ) > 0 ) {
$current_tweet = self::start_new_tweet();
}
$current_tweet['tweet'] = $block['tweet'];
self::save_current_tweet( $current_tweet, $block );
}
/**
* Check if the block has an embed URL that we can append to the current tweet text.
*
* @param array $block The block to process.
*/
private static function add_embed_to_tweets( $block ) {
if ( 0 === strlen( $block['embed'] ) ) {
return;
}
$current_tweet = self::get_current_tweet();
$reserved_characters = count( $current_tweet['media'] ) * self::$characters_per_media;
$reserved_characters += 1 + self::$characters_per_url;
// We can only attach an embed to the previous tweet if it doesn't already
// have any URLs in it. Also, we can't attach it if it'll make the tweet too long.
if ( preg_match( '/url-placeholder-\d+-*/', $current_tweet['text'] ) || ! self::is_valid_tweet( $current_tweet['text'], $reserved_characters ) ) {
$current_tweet = self::start_new_tweet();
$current_tweet['text'] = self::generate_url_placeholder( $block['embed'] );
} else {
$space = empty( $current_tweet['text'] ) ? '' : ' ';
$current_tweet['text'] .= $space . self::generate_url_placeholder( $block['embed'] );
}
self::save_current_tweet( $current_tweet, $block );
}
/**
* Given an array of blocks and optional editor information, this will extract them into
* the internal representation used during parsing.
*
* @param array $blocks An array of blocks and optional editor-related information.
* @return array An array of blocks, in our internal representation.
*/
private static function extract_blocks( $blocks ) {
if ( empty( $blocks ) ) {
return array();
}
$block_count = count( $blocks );
for ( $ii = 0; $ii < $block_count; $ii++ ) {
if ( ! self::get_block_definition( $blocks[ $ii ]['block']['blockName'] ) ) {
unset( $blocks[ $ii ] );
continue;
}
$blocks[ $ii ]['name'] = $blocks[ $ii ]['block']['blockName'];
$blocks[ $ii ]['text'] = self::extract_text_from_block( $blocks[ $ii ]['block'] );
$blocks[ $ii ]['media'] = self::extract_media_from_block( $blocks[ $ii ]['block'] );
$blocks[ $ii ]['tweet'] = self::extract_tweet_from_block( $blocks[ $ii ]['block'] );
$blocks[ $ii ]['embed'] = self::extract_embed_from_block( $blocks[ $ii ]['block'] );
}
return array_values( $blocks );
}
/**
* Creates a blank tweet, appends it to the tweets array, and returns the tweet.
*
* @return array The blank tweet.
*/
private static function start_new_tweet() {
self::$tweets[] = array(
// An array of blocks that make up this tweet.
'blocks' => array(),
// If this tweet only contains part of a block, the boundary contains
// information about where in the block the tweet ends.
'boundary' => false,
// The text content of the tweet.
'text' => '',
// The media content of the tweet.
'media' => array(),
// The quoted tweet in this tweet.
'tweet' => '',
// Some blocks force a hard finish to the tweet, even if subsequent blocks
// could technically be appended. This flag shows when a tweet is finished.
'finished' => false,
// Flag if the current tweet already has content in it.
'changed' => false,
);
return self::get_current_tweet();
}
/**
* Get the last tweet in the array.
*
* @return array The tweet.
*/
private static function get_current_tweet() {
return end( self::$tweets );
}
/**
* Saves the passed tweet array as the last tweet, overwriting the former last tweet.
*
* This method adds some last minute checks: marking the tweet as "changed", as well
* as adding the $block to the tweet (if it was passed, and hasn't already been added).
*
* @param array $tweet The tweet being stored.
* @param array $block Optional. The block that was used to modify this tweet.
* @return array The saved tweet, after the last minute checks have been done.
*/
private static function save_current_tweet( $tweet, $block = null ) {
$tweet['changed'] = true;
if ( isset( $block ) ) {
$block_def = self::get_block_definition( $block['name'] );
// Check if this block type will be forcing a new tweet.
if ( $block_def['force_finished'] ) {
$tweet['finished'] = true;
}
// Check if this block is already recorded against this tweet.
$last_block = end( $tweet['blocks'] );
if ( isset( $block['clientId'] ) && ( false === $last_block || $last_block['clientId'] !== $block['clientId'] ) ) {
$tweet['blocks'][] = $block;
}
}
// Find the index of the last tweet in the array.
end( self::$tweets );
$tweet_index = key( self::$tweets );
self::$tweets[ $tweet_index ] = $tweet;
return $tweet;
}
/**
* Checks if the passed text is valid for a tweet or not.
*
* @param string $text The text to check.
* @param int $reserved_characters Optional. The number of characters to reduce the maximum tweet length by.
* @return bool Whether or not the text is valid.
*/
private static function is_valid_tweet( $text, $reserved_characters = 0 ) {
return self::is_within_twitter_length( $text, 280 - $reserved_characters );
}
/**
* Checks if the passed text is valid for image alt text.
*
* @param string $text The text to check.
* @return bool Whether or not the text is valid.
*/
private static function is_valid_alt_text( $text ) {
return self::is_within_twitter_length( $text, 1000 );
}
/**
* Check if a string is shorter than a given length, according to Twitter's rules for counting string length.
*
* @param string $text The text to check.
* @param int $max_length The number of characters long this string can be.
* @return bool Whether or not the string is no longer than the length limit.
*/
private static function is_within_twitter_length( $text, $max_length ) {
// Replace all multiline separators with a \n, since that's the
// character we actually want to count.
$text = str_replace( self::$line_separator, "\n", $text );
// Keep a running total of characters we've removed.
$stripped_characters = 0;
// Since we use '…' a lot, strip it out, so we can still use the ASCII checks.
$ellipsis_count = 0;
$text = str_replace( '…', '', $text, $ellipsis_count );
// The ellipsis glyph counts for two characters.
$stripped_characters += $ellipsis_count * 2;
// Try filtering out emoji first, since ASCII text + emoji is a relatively common case.
if ( ! self::is_ascii( $text ) ) {
// Initialise the emoji cache.
if ( 0 === count( self::$emoji_list ) ) {
self::$emoji_list = array_map( 'html_entity_decode', _wp_emoji_list( 'entities' ) );
}
$emoji_count = 0;
$text = str_replace( self::$emoji_list, '', $text, $emoji_count );
// Emoji graphemes count as 2 characters each.
$stripped_characters += $emoji_count * 2;
}
if ( self::is_ascii( $text ) ) {
$stripped_characters += strlen( $text );
if ( $stripped_characters <= $max_length ) {
return true;
}
return false;
}
// Remove any glyphs that count as 1 character.
// Source: https://github.com/twitter/twitter-text/blob/master/config/v3.json .
// Note that the source ranges are in decimal, the regex ranges are converted to hex.
$single_character_count = 0;
$text = preg_replace( '/[\x{0000}-\x{10FF}\x{2000}-\x{200D}\x{2010}-\x{201F}\x{2032}-\x{2037}]/uS', '', $text, -1, $single_character_count );
$stripped_characters += $single_character_count;
// Check if there's any text we haven't counted yet.
// Any remaining glyphs count as 2 characters each.
if ( 0 !== strlen( $text ) ) {
// WP provides a compat version of mb_strlen(), no need to check if it exists.
$stripped_characters += mb_strlen( $text, 'UTF-8' ) * 2;
}
if ( $stripped_characters <= $max_length ) {
return true;
}
return false;
}
/**
* Checks if a string only contains ASCII characters.
*
* @param string $text The string to check.
* @return bool Whether or not the string is ASCII-only.
*/
private static function is_ascii( $text ) {
if ( function_exists( 'mb_check_encoding' ) ) {
if ( mb_check_encoding( $text, 'ASCII' ) ) {
return true;
}
} elseif ( ! preg_match( '/[^\x00-\x7F]/', $text ) ) {
return true;
}
return false;
}
/**
* A block will generate a certain amount of text to be inserted into a tweet. If that text is too
* long for a tweet, we already know where the text will be split when it's published as tweet, but
* we need to calculate where that corresponds to in the block edit UI.
*
* The tweet template for that block may add extra characters, extra characters are added for URL
* placeholders, and the block may contain multiple RichText areas (corresponding to attributes),
* so we need to keep track of both until the this function calculates which attribute area (in the
* block editor, the richTextIdentifier) that offset corresponds to, and how far into that attribute
* area it is.
*
* @param array $block The block being checked.
* @param integer $offset The position in the tweet text where it will be split.
* @return array|false `false` if the boundary can't be determined. Otherwise, returns the
* position in the block editor to insert the tweet boundary annotation.
*/
private static function get_boundary( $block, $offset ) {
// If we don't have a clientId, there's no point in generating a boundary, since this
// parse request doesn't have a way to map blocks back to editor UI.
if ( ! isset( $block['clientId'] ) ) {
return false;
}
$block_def = self::get_block_definition( $block['name'] );
if ( isset( $block_def['content'] ) && count( $block_def['content'] ) > 0 ) {
$tags = $block_def['content'];
} else {
$tags = array( 'content' );
}
$tag_content = self::extract_tag_content_from_html( $tags, $block['block']['innerHTML'] );
// $tag_content is split up by tag first, then lines. We want to remap it to split it by lines
// first, then tag.
$lines = array();
foreach ( $tag_content as $tag => $content ) {
if ( 'content' === $tag ) {
$attribute_name = 'content';
} else {
$attribute_name = array_search( $tag, $block_def['content'], true );
}
foreach ( $content as $id => $content_string ) {
// Multiline blocks can have multiple lines, but other blocks will always only have 1.
if ( 'multiline' === $block_def['type'] ) {
$line_number = $id;
} else {
$line_number = 0;
}
if ( ! isset( $lines[ $line_number ] ) ) {
$lines[ $line_number ] = array();
}
if ( ! isset( $lines[ $line_number ][ $attribute_name ] ) ) {
// For multiline blocks, or the first time this attribute has been encountered
// in single line blocks, assign the string to the line/attribute.
$lines[ $line_number ][ $attribute_name ] = $content_string;
} else {
// For subsequent times this line/attribute is encountered (only in single line blocks),
// append the string with a line break.
$lines[ $line_number ][ $attribute_name ] .= "\n$content_string";
}
}
}
$line_count = count( $lines );
$template_parts = preg_split( '/({{\w+}})/', $block_def['template'], -1, PREG_SPLIT_DELIM_CAPTURE );
// Keep track of the total number of bytes we've processed from this block.
$total_bytes_processed = 0;
// Keep track of the number of characters that the processed data translates to in the editor.
$characters_processed = 0;
foreach ( $lines as $line_number => $line ) {
// Add up the length of all the parts of this line.
$line_byte_total = array_sum( array_map( 'strlen', $line ) );
if ( $line_byte_total > 0 ) {
// We have something to use in the template, so loop over each part of the template, and count it.
foreach ( $template_parts as $template_part ) {
$matches = array();
if ( preg_match( '/{{(\w+)}}/', $template_part, $matches ) ) {
$part_name = $matches[1];
$line_part_data = $line[ $part_name ];
$line_part_bytes = strlen( $line_part_data );
$cleaned_line_part_data = preg_replace( '/ \(url-placeholder-\d+-*\)/', '', $line_part_data );
$cleaned_line_part_data = preg_replace_callback(
'/url-placeholder-(\d+)-*/',
function ( $matches ) {
return self::$urls[ $matches[1] ];
},
$cleaned_line_part_data
);
if ( $total_bytes_processed + $line_part_bytes >= $offset ) {
// We know that the offset is somewhere inside this part of the tweet, but we need to remove the length
// of any URL placeholders that appear before the boundary, to be able to calculate the correct attribute offset.
// $total_bytes_processed is the sum of everything we've processed so far, (including previous parts)
// on this line. This makes it relatively easy to calculate the number of bytes into this part
// that the boundary will occur.
$line_part_byte_boundary = $offset - $total_bytes_processed;
// Grab the data from this line part that appears before the boundary.
$line_part_pre_boundary_data = substr( $line_part_data, 0, $line_part_byte_boundary );
// Remove any URL placeholders, since these aren't shown in the editor.
$line_part_pre_boundary_data = preg_replace( '/ \(url-placeholder-\d+-*\)/', '', $line_part_pre_boundary_data );
$line_part_pre_boundary_data = preg_replace_callback(
'/url-placeholder-(\d+)-*/',
function ( $matches ) {
return self::$urls[ $matches[1] ];
},
$line_part_pre_boundary_data
);
$boundary_start = self::utf_16_code_unit_length( $line_part_pre_boundary_data ) - 1;
// Multiline blocks need to offset for the characters that are in the same content area,
// but which were counted on previous lines.
if ( 'multiline' === $block_def['type'] ) {
$boundary_start += $characters_processed;
}
// Check if the boundary is happening on a line break or a space.
if ( "\n" === $line_part_data[ $line_part_byte_boundary - 1 ] ) {
$type = 'line-break';
// A line break boundary can actually be multiple consecutive line breaks,
// count them all up so we know how big the annotation needs to be.
$matches = array();
preg_match( '/\n+$/', substr( $line_part_data, 0, $line_part_byte_boundary ), $matches );
$boundary_end = $boundary_start + 1;
$boundary_start -= strlen( $matches[0] ) - 1;
} else {
$type = 'normal';
$boundary_end = $boundary_start + 1;
}
return array(
'start' => $boundary_start,
'end' => $boundary_end,
'container' => $part_name,
'type' => $type,
);
} else {
$total_bytes_processed += $line_part_bytes;
$characters_processed += self::utf_16_code_unit_length( $cleaned_line_part_data );
continue;
}
} else {
$total_bytes_processed += strlen( $template_part );
}
}
// Are we breaking at the end of this line?
if ( $total_bytes_processed + 1 === $offset && $line_count > 1 ) {
reset( $block_def['content'] );
$container = key( $block_def['content'] );
return array(
'line' => $line_number,
'container' => $container,
'type' => 'end-of-line',
);
}
// The newline at the end of each line is 1 byte, but we don't need to count empty lines.
$total_bytes_processed++;
}
// We do need to count empty lines in the editor, since they'll be displayed.
$characters_processed++;
}
return false;
}
/**
* JavaScript uses UTF-16 for encoding strings, which means we need to provide UTF-16
* based offsets for the block editor to render tweet boundaries in the correct location.
*
* UTF-16 is a variable-width character encoding: every code unit is 2 bytes, a single character
* can be one or two code units long. Fortunately for us, JavaScript's String.charAt() is based
* on the older UCS-2 character encoding, which only counts single code units. PHP's strlen()
* counts a code unit as being 2 characters, so once a string is converted to UTF-16, we have
* a fast way to determine how long it is in UTF-16 code units.
*
* @param string $text The natively encoded string to get the length of.
* @return int The length of the string in UTF-16 code units. Returns -1 if the length could not
* be calculated.
*/
private static function utf_16_code_unit_length( $text ) {
// If mb_convert_encoding() exists, we can use that for conversion.
if ( function_exists( 'mb_convert_encoding' ) ) {
// UTF-16 can add an additional code unit to the start of the string, called the
// Byte Order Mark (BOM), which indicates whether the string is encoding as
// big-endian, or little-endian. Since we don't want to count code unit, and the endianness
// doesn't matter for our purposes, using PHP's UTF-16BE encoding uses big-endian
// encoding, and ensures the BOM *won't* be prepended to the string to the string.
return strlen( mb_convert_encoding( $text, 'UTF-16BE' ) ) / 2;
}
// If we can't convert this string, return a result that will avoid an incorrect annotation being added.
return -1;
}
/**
* Extracts the tweetable text from a block.
*
* @param array $block A single block, as generated by parse_block().
* @return string The tweetable text from the block, in the correct template form.
*/
private static function extract_text_from_block( $block ) {
// If the block doesn't have an innerHTMl, we're not going to get any text.
if ( empty( $block['innerHTML'] ) ) {
return '';
}
$block_def = self::get_block_definition( $block['blockName'] );
// We currently only support extracting text from HTML text nodes.
if ( ! isset( $block_def['content_location'] ) || 'html' !== $block_def['content_location'] ) {
return '';
}
// Find out which tags we need to extract content from.
if ( isset( $block_def['content'] ) && count( $block_def['content'] ) > 0 ) {
$tags = $block_def['content'];
} else {
$tags = array( 'content' );
}
$tag_values = self::extract_tag_content_from_html( $tags, $block['innerHTML'] );
// We can treat single line blocks as "multiline", with only one line in them.
$lines = array();
foreach ( $tag_values as $tag => $values ) {
// For single-line blocks, we need to squash all the values for this tag into a single value.
if ( 'multiline' !== $block_def['type'] ) {
$values = array( implode( "\n", $values ) );
}
// Handle the special "content" tag.
if ( 'content' === $tag ) {
$placeholder = 'content';
} else {
$placeholder = array_search( $tag, $block_def['content'], true );
}
// Loop over each instance of this value, appling that value to the corresponding line template.
foreach ( $values as $line_number => $value ) {
if ( ! isset( $lines[ $line_number ] ) ) {
$lines[ $line_number ] = $block_def['template'];
}
$lines[ $line_number ] = str_replace( '{{' . $placeholder . '}}', $value, $lines[ $line_number ] );
}
}
// Remove any lines that didn't apply any content.
$empty_template = preg_replace( '/{{.*?}}/', '', $block_def['template'] );
$lines = array_filter(
$lines,
function ( $line ) use ( $empty_template ) {
return $line !== $empty_template;
}
);
// Join the lines together into a single string.
$text = implode( self::$line_separator, $lines );
// Trim off any trailing whitespace that we no longer need.
$text = preg_replace( '/(\s|' . self::$line_separator . ')+$/u', '', $text );
return $text;
}
/**
* Extracts the tweetable media from a block.
*
* @param array $block A single block, as generated by parse_block().
* @return array {
* An array of media.
*
* @type string url The URL of the media.
* @type string alt The alt text of the media.
* }
*/
private static function extract_media_from_block( $block ) {
$block_def = self::get_block_definition( $block['blockName'] );
$media = array();
if ( 'image' === $block_def['type'] ) {
$url = self::extract_attr_content_from_html(
$block_def['content']['url'][0],
$block_def['content']['url'][1],
$block['innerHTML']
);
$alt = self::extract_attr_content_from_html(
$block_def['content']['alt'][0],
$block_def['content']['alt'][1],
$block['innerHTML']
);
$img_count = count( $url );
for ( $ii = 0; $ii < $img_count; $ii++ ) {
$filedata = wp_check_filetype( basename( wp_parse_url( $url[ $ii ], PHP_URL_PATH ) ) );
$media[] = array(
'url' => $url[ $ii ],
'alt' => self::is_valid_alt_text( $alt[ $ii ] ) ? $alt[ $ii ] : '',
'type' => $filedata['type'],
);
}
} elseif ( 'video' === $block_def['type'] ) {
// Handle VideoPress videos.
if ( isset( $block['attrs']['src'] ) && 0 === strpos( $block['attrs']['src'], 'https://videos.files.wordpress.com/' ) ) {
$url = array( $block['attrs']['src'] );
} else {
$url = self::extract_attr_content_from_html(
$block_def['content']['url'][0],
$block_def['content']['url'][1],
$block['innerHTML']
);
}
// We can only ever use the first video found, no need to go through all of them.
if ( count( $url ) > 0 ) {
$filedata = wp_check_filetype( basename( wp_parse_url( $url[0], PHP_URL_PATH ) ) );
$media[] = array(
'url' => $url[0],
'type' => $filedata['type'],
);
}
}
return $media;
}
/**
* Extracts the tweet URL from a Twitter embed block.
*
* @param array $block A single block, as generated by parse_block().
* @return string The tweet URL. Empty string if there is none available.
*/
private static function extract_tweet_from_block( $block ) {
if (
'core/embed' === $block['blockName']
&& ( isset( $block['attrs']['providerNameSlug'] ) && 'twitter' === $block['attrs']['providerNameSlug'] )
) {
return $block['attrs']['url'];
}
return '';
}
/**
* Extracts URL from an embed block.
*
* @param array $block A single block, as generated by parse_block().
* @return string The URL. Empty string if there is none available.
*/
private static function extract_embed_from_block( $block ) {
$block_def = self::get_block_definition( $block['blockName'] );
if ( 'embed' !== $block_def['type'] ) {
return '';
}
// Twitter embeds are handled in ::extract_tweet_from_block().
if (
'core/embed' === $block['blockName']
&& ( isset( $block['attrs']['providerNameSlug'] ) && 'twitter' === $block['attrs']['providerNameSlug'] )
) {
return '';
}
$url = '';
if ( 'block-attributes' === $block_def['content_location'] ) {
$url = $block['attrs'][ $block_def['content'][0] ];
}
if ( 'jetpack/gif' === $block['blockName'] ) {
$url = str_replace( '/embed/', '/gifs/', $url );
}
return $url;
}
/**
* There's a bunch of left-over cruft in the tweets array that we don't need to return. Removing
* it helps keep the size of the data down.
*/
private static function clean_return_tweets() {
// Before we return, clean out unnecessary cruft from the return data.
$tweets = array_map(
function ( $tweet ) {
// Remove tweets that don't have anything saved in them. eg, if the last block is a
// header with no text, it'll force a new tweet, but we won't end up putting anything
// in that tweet.
if ( ! $tweet['changed'] ) {
return false;
}
// Replace any URL placeholders that appear in the text.
$tweet['urls'] = array();
foreach ( self::$urls as $id => $url ) {
$count = 0;
$tweet['text'] = str_replace( str_pad( "url-placeholder-$id", self::$characters_per_url, '-' ), $url, $tweet['text'], $count );
// If we found a URL, keep track of it for the editor.
if ( $count > 0 ) {
$tweet['urls'][] = $url;
}
}
// Remove any inline placeholders.
$tweet['text'] = str_replace( self::$inline_placeholder, '', $tweet['text'] );
// If the tweet text consists only of whitespace, we can remove all of it.
if ( preg_match( '/^\s*$/u', $tweet['text'] ) ) {
$tweet['text'] = '';
}
// Remove trailing whitespace from every line.
$tweet['text'] = preg_replace( '/\p{Z}+$/um', '', $tweet['text'] );
// Remove all trailing whitespace (including line breaks) from the end of the text.
$tweet['text'] = rtrim( $tweet['text'] );
// Remove internal flags.
unset( $tweet['changed'] );
unset( $tweet['finished'] );
// Remove bulky block data.
if ( ! isset( $tweet['blocks'][0]['attributes'] ) && ! isset( $tweet['blocks'][0]['clientId'] ) ) {
$tweet['blocks'] = array();
} else {
// Remove the parts of the block data that the editor doesn't need.
$block_count = count( $tweet['blocks'] );
for ( $ii = 0; $ii < $block_count; $ii++ ) {
$keys = array_keys( $tweet['blocks'][ $ii ] );
foreach ( $keys as $key ) {
// The editor only needs these attributes, everything else will be unset.
if ( in_array( $key, array( 'attributes', 'clientId' ), true ) ) {
continue;
}
unset( $tweet['blocks'][ $ii ][ $key ] );
}
}
}
// Once we've finished cleaning up, check if there's anything left to be tweeted.
if ( empty( $tweet['text'] ) && empty( $tweet['media'] ) && empty( $tweet['tweet'] ) ) {
return false;
}
return $tweet;
},
self::$tweets
);
// Clean any removed tweets out of the result.
return array_values( array_filter( $tweets, 'is_array' ) );
}
/**
* Given a list of tags and a HTML blob, this will extract the text content inside
* each of the given tags.
*
* @param array $tags An array of tag names.
* @param string $html A blob of HTML.
* @return array An array of the extract content. The keys in the array are the $tags,
* each value is an array. The value array is indexed in the same order as the tag
* appears in the HTML blob, including nested tags.
*/
private static function extract_tag_content_from_html( $tags, $html ) {
// Serialised blocks will sometimes wrap the innerHTML in newlines, but those newlines
// are removed when innerHTML is parsed into an attribute. Remove them so we're working
// with the same information.
if ( "\n" === $html[0] && "\n" === $html[ strlen( $html ) - 1 ] ) {
$html = substr( $html, 1, strlen( $html ) - 2 );
}
// Normalise <br>.
$html = preg_replace( '/<br\s*\/?>/', '<br>', $html );
// If there were no tags passed, assume the entire text is required.
if ( empty( $tags ) ) {
$tags = array( 'content' );
}
$values = array();
$tokens = wp_html_split( $html );
$validator = new Twitter_Validator();
foreach ( $tags as $tag ) {
$values[ $tag ] = array();
// Since tags can be nested, keeping track of the nesting level allows
// us to extract nested content into a flat array.
if ( 'content' === $tag ) {
// The special "content" tag means we should store the entire content,
// so assume the tag is open from the beginning.
$opened = 0;
$closed = -1;
$values['content'][0] = '';
} else {
$opened = -1;
$closed = -1;
}
// When we come across a URL, we need to keep track of it, so it can then be inserted
// in the right place.
$current_url = '';
foreach ( $tokens as $token ) {
if ( 0 === strlen( $token ) ) {
// Skip any empty tokens.
continue;
}
// If we're currently storing content, check if it's a text-formatting
// tag that we should apply.
if ( $opened !== $closed ) {
// End of a paragraph, put in some newlines (as long as we're not extracting paragraphs).
if ( '</p>' === $token && 'p' !== $tag ) {
$values[ $tag ][ $opened ] .= "\n\n";
}
// A line break gets one newline.
if ( '<br>' === $token ) {
$values[ $tag ][ $opened ] .= "\n";
}
// A link has opened, grab the URL for inserting later.
if ( 0 === strpos( $token, '<a ' ) ) {
$href_values = self::extract_attr_content_from_html( 'a', 'href', $token );
if ( ! empty( $href_values[0] ) && $validator->isValidURL( $href_values[0] ) ) {
// Remember the URL.
$current_url = $href_values[0];
}
}
// A link has closed, insert the URL from that link if we have one.
if ( '</a>' === $token && '' !== $current_url ) {
// Generate a unique-to-this-block placeholder which takes up the
// same number of characters as a URL does.
$values[ $tag ][ $opened ] .= ' (' . self::generate_url_placeholder( $current_url ) . ')';
$current_url = '';
}
// We don't return inline images, but they technically take up 1 character in the RichText.
if ( 0 === strpos( $token, '<img ' ) ) {
$values[ $tag ][ $opened ] .= self::$inline_placeholder;
}
}
if ( "<$tag>" === $token || 0 === strpos( $token, "<$tag " ) ) {
// A tag has just been opened.
$opened++;
// Set an empty value now, so we're keeping track of empty tags.
if ( ! isset( $values[ $tag ][ $opened ] ) ) {
$values[ $tag ][ $opened ] = '';
}
continue;
}
if ( "</$tag>" === $token ) {
// The tag has been closed.
$closed++;
continue;
}
if ( '<' === $token[0] ) {
// We can skip any other tags.
continue;
}
if ( $opened !== $closed ) {
// We're currently in a tag, with some content. Start by decoding any HTML entities.
$token = html_entity_decode( $token, ENT_QUOTES );
// Find any URLs in this content, and replace them with a placeholder.
preg_match_all( Twitter_Regex::getValidUrlMatcher(), $token, $matches, PREG_SET_ORDER | PREG_OFFSET_CAPTURE );
$offset = 0;
foreach ( $matches as $match ) {
list( $url, $start ) = $match[2];
$token = substr_replace( $token, self::generate_url_placeholder( $url ), $start + $offset, strlen( $url ) );
$offset += self::$characters_per_url - strlen( $url );
// If we're in a link with a URL set, there's no need to keep two copies of the same link.
if ( ! empty( $current_url ) ) {
$lower_url = strtolower( $url );
$lower_current_url = strtolower( $current_url );
if ( $lower_url === $lower_current_url ) {
$current_url = '';
}
// Check that the link text isn't just a shortened version of the href value.
$trimmed_current_url = preg_replace( '|^https?://|', '', $lower_current_url );
if ( $lower_url === $trimmed_current_url || trim( $trimmed_current_url, '/' ) === $lower_url ) {
$current_url = '';
}
}
}
// Append it to the right value.
$values[ $tag ][ $opened ] .= $token;
}
}
}
return $values;
}
/**
* Extracts the attribute content from a tag.
*
* This method allows for the HTML to have multiple instances of the tag, and will return
* an array containing the attribute value (or an empty string, if the tag doesn't have the
* requested attribute) for each occurrence of the tag.
*
* @param string $tag The tag we're looking for.
* @param string $attr The name of the attribute we're looking for.
* @param string $html The HTML we're searching through.
* @param array $attr_filters Optional. Filters tags based on whether or not they have attributes with given values.
* @return array The array of attribute values found.
*/
private static function extract_attr_content_from_html( $tag, $attr, $html, $attr_filters = array() ) {
// Given our single tag and attribute, construct a KSES filter for it.
$kses_filter = array(
$tag => array(
$attr => array(),
),
);
foreach ( $attr_filters as $filter_attr => $filter_value ) {
$kses_filter[ $tag ][ $filter_attr ] = array();
}
// Remove all HTML except for the tag we're after. On that tag,
// remove all attributes except for the one we're after.
$stripped_html = wp_kses( $html, $kses_filter );
$values = array();
$tokens = wp_html_split( $stripped_html );
foreach ( $tokens as $token ) {
$found_value = '';
if ( 0 === strlen( $token ) ) {
// Skip any empty tokens.
continue;
}
if ( '<' !== $token[0] ) {
// We can skip any non-tag tokens.
continue;
}
$token_attrs = wp_kses_attr_parse( $token );
// Skip tags that KSES couldn't handle.
if ( false === $token_attrs ) {
continue;
}
// Remove the tag open and close chunks.
$found_tag = array_shift( $token_attrs );
array_pop( $token_attrs );
// We somehow got a tag that isn't the one we're after. Skip it.
if ( 0 !== strpos( $found_tag, "<$tag " ) ) {
continue;
}
// We can only fail an attribute filter if one is set.
$passed_filter = count( $attr_filters ) === 0;
foreach ( $token_attrs as $token_attr_string ) {
// The first "=" in the string will be between the attribute name/value.
list( $token_attr_name, $token_attr_value ) = explode( '=', $token_attr_string, 2 );
$token_attr_name = trim( $token_attr_name );
$token_attr_value = trim( $token_attr_value );
// Remove a single set of quotes from around the value.
if ( '' !== $token_attr_value && in_array( $token_attr_value[0], array( '"', "'" ), true ) ) {
$token_attr_value = trim( $token_attr_value, $token_attr_value[0] );
}
// If this is the attribute we're after, save the value for the end of the loop.
if ( $token_attr_name === $attr ) {
$found_value = $token_attr_value;
}
if ( isset( $attr_filters[ $token_attr_name ] ) && $attr_filters[ $token_attr_name ] === $token_attr_value ) {
$passed_filter = true;
}
}
if ( $passed_filter ) {
// We always want to append the found value, even if we didn't "find" a matching attribute.
// An empty string in the return value means that we found the tag, but the attribute was
// either empty, or not set.
$values[] = html_entity_decode( $found_value, ENT_QUOTES );
}
}
return $values;
}
/**
* Generates a placeholder for URLs, using the appropriate number of characters to imitate how
* Twitter counts the length of URLs in tweets.
*
* @param string $url The URL to generate a placeholder for.
* @return string The placeholder.
*/
public static function generate_url_placeholder( $url ) {
self::$urls[] = $url;
return str_pad( 'url-placeholder-' . ( count( self::$urls ) - 1 ), self::$characters_per_url, '-' );
}
/**
* Retrieves the Twitter card data for a list of URLs.
*
* @param array $urls The list of URLs to grab Twitter card data for.
* @return array The Twitter card data.
*/
public static function generate_cards( $urls ) {
$validator = new Twitter_Validator();
$requests = array_map(
function ( $url ) use ( $validator ) {
if (
false !== wp_http_validate_url( $url )
&& $validator->isValidURL( $url )
) {
return array(
'url' => $url,
);
}
return false;
},
$urls
);
$requests = array_filter( $requests );
$hooks = new Requests_Hooks();
$hooks->register(
'requests.before_redirect',
array( self::class, 'validate_redirect_url' )
);
$results = Requests::request_multiple( $requests, array( 'hooks' => $hooks ) );
foreach ( $results as $result ) {
if ( $result instanceof Requests_Exception ) {
return new WP_Error(
'invalid_url',
__( 'Sorry, something is wrong with the requested URL.', 'jetpack' ),
403
);
}
}
$card_data = array(
'creator' => array(
'name' => 'twitter:creator',
),
'description' => array(
'name' => 'twitter:description',
'property' => 'og:description',
),
'image' => array(
'name' => 'twitter:image',
'property' => 'og:image:secure',
'property' => 'og:image',
),
'title' => array(
'name' => 'twitter:text:title',
'property' => 'og:title',
),
'type' => array(
'name' => 'twitter:card',
),
);
$cards = array();
foreach ( $results as $id => $result ) {
$url = $requests[ $id ]['url'];
if ( ! $result->success ) {
$cards[ $url ] = array(
'error' => 'invalid_url',
);
continue;
}
$url_card_data = array();
foreach ( $card_data as $key => $filters ) {
foreach ( $filters as $attribute => $value ) {
$found_data = self::extract_attr_content_from_html( 'meta', 'content', $result->body, array( $attribute => $value ) );
if ( count( $found_data ) > 0 && strlen( $found_data[0] ) > 0 ) {
$url_card_data[ $key ] = html_entity_decode( $found_data[0], ENT_QUOTES );
break;
}
}
}
if ( count( $url_card_data ) > 0 ) {
$cards[ $url ] = $url_card_data;
} else {
$cards[ $url ] = array(
'error' => 'no_og_data',
);
}
}
return $cards;
}
/**
* Filters the redirect URLs that can appear when requesting passed URLs.
*
* @param String $redirect_url the URL to which a redirect is requested.
* @throws Requests_Exception In case the URL is not validated.
* @return void
* */
public static function validate_redirect_url( $redirect_url ) {
if ( ! wp_http_validate_url( $redirect_url ) ) {
throw new Requests_Exception( __( 'A valid URL was not provided.', 'jetpack' ), 'wp_http.redirect_failed_validation' );
}
}
/**
* Get the WPCOM or self-hosted site ID.
*
* @return mixed
*/
public static function get_site_id() {
$is_wpcom = ( defined( 'IS_WPCOM' ) && IS_WPCOM );
$site_id = $is_wpcom ? get_current_blog_id() : Jetpack_Options::get_option( 'id' );
if ( ! $site_id ) {
return new WP_Error(
'unavailable_site_id',
__( 'Sorry, something is wrong with your Jetpack connection.', 'jetpack' ),
403
);
}
return (int) $site_id;
}
}