[3.0] Limits a print page to one page of posts

Languages/en_US/Help.php

@@ -220,7 +220,7 @@
 	</ul>';
 
 $helptxt['topicSummaryPosts'] = 'This allows you to set the number of previous posts shown in the topic summary on the reply page.';
-$helptxt['enableAllMessages'] = 'Set this to the <em>maximum</em> number of posts a topic can have to show the <em>all</em> link. Setting this lower than &quot;Maximum messages to display in a topic page&quot; will simply mean it never gets shown, and setting it too high could slow down your forum.';
+$helptxt['enableAllMessages'] = 'Set this to the <em>maximum</em> number of posts a topic can have to show the <em>all</em> link. Setting this lower than &quot;Maximum messages to display in a topic page&quot; will simply mean it never gets shown, and setting it too high could slow down your forum. The print view of a topic shows this many posts at a time as well, and falls back to a limit of its own when the <em>all</em> link is turned off here.';
 $helptxt['allow_guestAccess'] = 'Unchecking this box will stop guests from doing anything but very basic actions on your forum - login, register, password reminder, etc. - on your forum. This is not the same as disallowing guest access to boards.';
 $helptxt['userLanguage'] = 'Turning this setting on will allow users to select which language file they use. It will not affect the
 		default selection.';

Sources/Actions/TopicPrint.php

@@ -24,6 +24,7 @@
 use SMF\Db\DatabaseApi as Db;
 use SMF\ErrorHandler;
 use SMF\Lang;
+use SMF\PageIndex;
 use SMF\Parser;
 use SMF\Poll;
 use SMF\Routable;
@@ -43,6 +44,16 @@ class TopicPrint implements ActionInterface, Routable
 	use ActionSuffixRouter;
 	use ActionTrait;
 
+	/*****************
+	 * Class constants
+	 *****************/
+
+	/**
+	 * The number of posts to show on one print page in forums that never show
+	 * the "All" view.
+	 */
+	public const DEFAULT_MAX_POSTS = 250;
+
 	/****************
 	 * Public methods
 	 ****************/
@@ -97,7 +108,56 @@ public function execute(): void
 		$row = Db::$db->fetch_assoc($request);
 		Db::$db->free_result($request);
 
-		if (!empty($row['id_poll'])) {
+		// Only the posts this user is allowed to see are printed or counted.
+		$approval_filter = Config::$modSettings['postmod_active'] && !User::$me->allowedTo('approve_posts') ? '
+				AND (m.approved = {int:is_approved}' . (User::$me->is_guest ? '' : ' OR m.id_member = {int:current_member}') . ')' : '';
+
+		$request = Db::$db->query(
+			'SELECT COUNT(*)
+			FROM {db_prefix}messages AS m
+			WHERE m.id_topic = {int:current_topic}' . $approval_filter,
+			[
+				'current_topic' => Topic::$topic_id,
+				'is_approved' => 1,
+				'current_member' => User::$me->id,
+			],
+		);
+		list($total_posts) = Db::$db->fetch_row($request);
+		Db::$db->free_result($request);
+
+		$per_page = $this->getPostsPerPage();
+
+		Utils::$context['start'] = (int) $_REQUEST['start'];
+
+		$page_index = new PageIndex(
+			Config::$scripturl . '?action=printpage;topic=' . Topic::$topic_id . '.%1$d' . (isset($_REQUEST['images']) ? ';images' : ''),
+			Utils::$context['start'],
+			(int) $total_posts,
+			$per_page,
+			true,
+			true,
+			// The print page carries its own styles and no scripts, so the
+			// icons and the expanding page list have to be plain text here.
+			[
+				'previous_page' => Lang::getTxt('prev', file: 'General'),
+				'next_page' => Lang::getTxt('next', file: 'General'),
+				'expand_pages' => ' ... ',
+			],
+		);
+
+		// If the supplied start value was invalid, redirect to the correct one.
+		if ($_REQUEST['start'] != Utils::$context['start']) {
+			Utils::redirectexit(\sprintf($page_index->base_url, Utils::$context['start']));
+		}
+
+		// There is nothing to navigate when the whole topic fits on one page.
+		if ($total_posts > $per_page) {
+			Utils::$context['page_index'] = $page_index;
+		}
+
+		// The poll belongs to the topic rather than to any of its posts, so it
+		// is printed once, with the first page.
+		if (!empty($row['id_poll']) && Utils::$context['start'] === 0) {
 			$poll = Poll::load(Topic::$topic_id, Poll::LOAD_BY_TOPIC);
 			Utils::$context['poll'] = $poll->format(['no_buttons' => true]);
 		}
@@ -120,13 +180,15 @@ public function execute(): void
 			'SELECT subject, poster_time, body, COALESCE(mem.real_name, poster_name) AS poster_name, id_msg
 			FROM {db_prefix}messages AS m
 				LEFT JOIN {db_prefix}members AS mem ON (mem.id_member = m.id_member)
-			WHERE m.id_topic = {int:current_topic}' . (Config::$modSettings['postmod_active'] && !User::$me->allowedTo('approve_posts') ? '
-				AND (m.approved = {int:is_approved}' . (User::$me->is_guest ? '' : ' OR m.id_member = {int:current_member}') . ')' : '') . '
-			ORDER BY m.id_msg',
+			WHERE m.id_topic = {int:current_topic}' . $approval_filter . '
+			ORDER BY m.id_msg
+			LIMIT {int:per_page} OFFSET {int:start}',
 			[
 				'current_topic' => Topic::$topic_id,
 				'is_approved' => 1,
 				'current_member' => User::$me->id,
+				'per_page' => $per_page,
+				'start' => Utils::$context['start'],
 			],
 		);
 		Utils::$context['posts'] = [];
@@ -215,4 +277,24 @@ public function execute(): void
 		// Set a canonical URL for this page.
 		Utils::$context['canonical_url'] = Config::$scripturl . '?topic=' . Topic::$topic_id . '.0';
 	}
+
+	/******************
+	 * Internal methods
+	 ******************/
+
+	/**
+	 * Works out how many posts belong on a single print page.
+	 *
+	 * A print page holds whole posts, parsed and in memory all at once, so it
+	 * shows no more of them at a time than the admin is willing to show in the
+	 * "All" view of a topic.
+	 *
+	 * @return int The maximum number of posts on one print page.
+	 */
+	protected function getPostsPerPage(): int
+	{
+		$per_page = (int) (Config::$modSettings['enableAllMessages'] ?? 0);
+
+		return $per_page > 0 ? $per_page : self::DEFAULT_MAX_POSTS;
+	}
 }

Themes/default/Printpage.template.php

@@ -224,12 +224,18 @@ function template_print_below()
  */
 function template_print_options()
 {
-	$url_text = Config::$scripturl . '?action=printpage;topic=' . Topic::$topic_id . '.0';
+	$url_text = Config::$scripturl . '?action=printpage;topic=' . Topic::$topic_id . '.' . Utils::$context['start'];
 	$url_images = $url_text . ';images';
 
 	echo '
 		<div class="print_options">';
 
+	// Long topics are printed a page at a time.
+	if (isset(Utils::$context['page_index'])) {
+		echo '
+			<div>', Utils::$context['page_index'], '</div>';
+	}
+
 	// Which option is set, text or text&images
 	if (isset($_REQUEST['images'])) {
 		echo '

tests/Integration/Http/TopicPrintTest.php

@@ -0,0 +1,187 @@
+<?php
+
+declare(strict_types=1);
+
+namespace SMF\Tests\Integration\Http;
+
+use PHPUnit\Framework\Attributes\CoversNothing;
+use SMF\Config;
+use SMF\Msg;
+use SMF\Topic;
+
+/**
+ * The print view of a topic, over HTTP.
+ *
+ * What is worth proving here is what a single request is willing to do. The
+ * print view renders whole posts with nothing else on the page, so a request for
+ * a long topic parses every post in it at once, and a visitor needs no account
+ * to ask for one. Only a real request shows how many posts come back, since the
+ * limit is applied in the action and the page is built by the template.
+ */
+#[CoversNothing]
+class TopicPrintTest extends HttpTestCase
+{
+	/*****************
+	 * Class constants
+	 *****************/
+
+	/**
+	 * How many posts to put in the test topic.
+	 */
+	private const POSTS = 5;
+
+	/**
+	 * How many of them a print page is allowed to show.
+	 */
+	private const PER_PAGE = 2;
+
+	/*********************
+	 * Internal properties
+	 *********************/
+
+	/**
+	 * @var array Topics this test created, to be removed afterwards.
+	 */
+	private array $created_topics = [];
+
+	/**
+	 * @var ?string The forum's own maximum topic size for the "All" view.
+	 */
+	private ?string $previous_max = null;
+
+	/****************
+	 * Public methods
+	 ****************/
+
+	public function testAPrintPageStopsAtOnePageOfPosts(): void
+	{
+		$topic_id = $this->seedTopic();
+
+		$first = $this->fetch('?action=printpage;topic=' . $topic_id . '.0');
+
+		$this->assertSame(
+			self::PER_PAGE,
+			$first->xpath('//div[@class="postheader"]')->length,
+			'the print page rendered the whole topic instead of one page of it',
+		);
+
+		$this->assertStringNotContainsString(
+			$this->bodyOfPost(self::POSTS),
+			$first->text(),
+			'the last post of the topic is on the first print page',
+		);
+
+		$this->assertNoErrorsLogged('printing a topic logged something.' . "\n");
+	}
+
+	public function testTheRestOfTheTopicIsOnTheFollowingPages(): void
+	{
+		$topic_id = $this->seedTopic();
+
+		$last = $this->fetch('?action=printpage;topic=' . $topic_id . '.' . (self::POSTS - 1));
+
+		$this->assertStringContainsString(
+			$this->bodyOfPost(self::POSTS),
+			$last->text(),
+			'the last post of the topic cannot be printed at all',
+		);
+
+		$this->assertNoErrorsLogged('printing the last page logged something.' . "\n");
+	}
+
+	/**
+	 * Without these the rest of a long topic is unreachable, since the print
+	 * page is the only thing that links to itself.
+	 */
+	public function testAPrintPageLinksToTheOtherPages(): void
+	{
+		$topic_id = $this->seedTopic();
+
+		$first = $this->fetch('?action=printpage;topic=' . $topic_id . '.0');
+
+		$this->assertGreaterThan(
+			0,
+			$first->xpath(
+				'//a[contains(@href, "action=printpage")][contains(@href, "topic=' . $topic_id . '.' . self::PER_PAGE . '")]',
+			)->length,
+			'the print page does not link to its second page',
+		);
+	}
+
+	/******************
+	 * Internal methods
+	 ******************/
+
+	protected function setUp(): void
+	{
+		parent::setUp();
+
+		// A print page shows no more posts than the "All" view is allowed to,
+		// so this is what decides where it stops.
+		$this->previous_max = $this->rawSetting('enableAllMessages');
+
+		Config::updateModSettings(['enableAllMessages' => self::PER_PAGE]);
+	}
+
+	protected function tearDown(): void
+	{
+		// Before the parent runs, while the connection is still ours.
+		Config::updateModSettings(['enableAllMessages' => (int) $this->previous_max]);
+
+		if ($this->created_topics !== []) {
+			Topic::remove($this->created_topics);
+
+			$this->created_topics = [];
+		}
+
+		parent::tearDown();
+	}
+
+	/**
+	 * Starts a topic holding more posts than one print page may show.
+	 *
+	 * @return int The new topic's id.
+	 */
+	private function seedTopic(): int
+	{
+		$this->actingAs($this->adminId());
+
+		$topic_id = 0;
+
+		for ($i = 1; $i <= self::POSTS; $i++) {
+			$msgOptions = [
+				'subject' => ($i === 1 ? '' : 'Re: ') . 'Print pagination',
+				'body' => $this->bodyOfPost($i),
+				'send_notifications' => false,
+			];
+			$topicOptions = [
+				'id' => $topic_id,
+				'board' => 1,
+			];
+			$posterOptions = [
+				'id' => $this->adminId(),
+			];
+
+			Msg::create($msgOptions, $topicOptions, $posterOptions);
+
+			$topic_id = (int) $topicOptions['id'];
+
+			if ($this->created_topics === []) {
+				$this->created_topics[] = $topic_id;
+			}
+		}
+
+		return $topic_id;
+	}
+
+	/**
+	 * The body of one of the seeded posts.
+	 *
+	 * @param int $number Which post.
+	 * @return string Its body.
+	 */
+	private function bodyOfPost(int $number): string
+	{
+		return 'Print pagination post number ' . $number . '.';
+	}
+}