tools/wikisource/run-wiki.php

<?php

use Goutte\Client;
use Symfony\Component\DomCrawler\Crawler;

require 'vendor/autoload.php';
$mainURL = 'https://wikisource.org/wiki/Category:Latvian';
$baseURL = 'https://wikisource.org';

$urls = [];

$httpClient = new Client();
$response = $httpClient->request('GET', $mainURL);

$dirname = 'wiki';
if (!mkdir($dirname) && !is_dir($dirname)) {
    throw new \RuntimeException(sprintf('Directory "%s" was not created', $dirname));
}

$response->filter('#mw-pages ul li a')->each(function ($node) use (&$urls, $baseURL) {
    $urls[] = $baseURL . $node->attr('href');
});

foreach ($urls as $url) {
    echo('Downloading: ' . $url . PHP_EOL);

    // wait a bit, to be nice to the server
    sleep(1);

    // load page
    $response = $httpClient->request('GET', $url);

    // set filename as page title
    $filename = $response->filter('#firstHeading .mw-page-title-main')->text() . '.txt';
    $filename = str_replace('/', '_', $filename);

    // navigate to the main content part
    $contentResponse = $response->filter('.mw-parser-output');

    // remove header with navigation
    $contentResponse->filter('#headertemplate')->each(function (Crawler $crawler) {
        foreach ($crawler as $node) {
            $node->parentNode->removeChild($node);
        }
    });

    // remove unexpected tags from content
    $contentResponse->filter(
        'dl, table, pre, style, #template-documentation, .ts-doc-footer, .mw-editsection, .toc'
    )->each(function (Crawler $crawler) {
        foreach ($crawler as $node) {
            $node->parentNode->removeChild($node);
        }
    });

    // remove external sites header
    $contentResponse->filter('h2')->last()->each(function (Crawler $crawler) {
        foreach ($crawler as $node) {
            $node->parentNode->removeChild($node);
        }
    });

    // remove external sites links
    $contentResponse->filter('ul')->last()->each(function (Crawler $crawler) {
        foreach ($crawler as $node) {
            $node->parentNode->removeChild($node);
        }
    });

    $fp = fopen($dirname . DIRECTORY_SEPARATOR . $filename,"wb");
    fwrite($fp, $contentResponse->text('', false));
    fclose($fp);
}