diff --git a/tests/scripts/find_duplicate_documents_by_md5.php b/tests/scripts/find_duplicate_documents_by_md5.php
new file mode 100644
index 0000000000..0b2187ef80
--- /dev/null
+++ b/tests/scripts/find_duplicate_documents_by_md5.php
@@ -0,0 +1,215 @@
+
+ */
+//exit; //remove this line to execute from the command line
+
+use ChamiloSession as Session;
+
+ini_set('memory_limit', '512M');
+
+require_once __DIR__.'/../../main/inc/global.inc.php';
+
+$html = false;
+$htmlEOL = '';
+if (PHP_SAPI !== 'cli') {
+ $html = true;
+ $htmlEOL = '
';
+ api_protect_admin_script();
+ //die('This script can only be executed from the command line');
+}
+
+// Debug shows more output
+$debug = false;
+// Ignore template files
+$ignoreTemplates = true;
+$webCode = api_get_path(WEB_CODE_PATH).'document/document.php?cidReq=';
+
+if ($html) {
+ echo "".$htmlEOL;
+}
+echo "[".time()."] Querying courses$htmlEOL\n";
+$sql = "SELECT id, code, directory FROM course order by id";
+
+$resCourse = Database::query($sql);
+if ($resCourse === false) {
+ exit('Could not find any course'.PHP_EOL);
+}
+$countCourses = Database::num_rows($resCourse);
+echo "[".time()."] Found $countCourses courses$htmlEOL".PHP_EOL;
+
+$md5Hashes = [];
+$md5Sizes = [];
+$totalDocs = 0;
+$totalDocsSize = 0;
+$uniqueDocs = 0;
+$duplicateDocsCount = 0;
+$totalDuplicateDocs = 0;
+$courseCodeDirMatch = [];
+$sysCoursePath = api_get_path(SYS_COURSE_PATH);
+
+// Search for duplicate tests, by looking for tests that have the exact same
+// title in the same course
+if ($debug) {
+ echo "[".time()."] Iterating on courses...$htmlEOL".PHP_EOL;
+}
+while ($course = Database::fetch_assoc($resCourse)) {
+ if ($debug) {
+ echo "Course ".$course['id'].' ('.$course['code'].')..'.$htmlEOL.PHP_EOL;
+ }
+ $courseCodeDirMatch[$course['code']] = $course['directory'];
+ $courseDir = $course['directory'].'/document';
+ $baseWorkDir = $sysCoursePath.$courseDir;
+ $totalDocs += _scanSubDirs($baseWorkDir, $md5Hashes, $md5Sizes, $course['code'], $ignoreTemplates);
+} // end while on course
+
+// Sort array by sizes
+arsort($md5Sizes, SORT_NUMERIC);
+
+echo "[".time()."] Here is a list of duplicate files, joined together$htmlEOL".PHP_EOL;
+echo " with a clickable link to each document:$htmlEOL".PHP_EOL;
+foreach ($md5Sizes as $hash => $size) {
+ $files = $md5Hashes[$hash];
+ $countFiles = $realFilesForThisHash = count($files);
+ $realFilePath = '';
+ $i = 0;
+ if ($countFiles > 1) {
+ $kSize = floor((int) $files[0]['size']/1024);
+ echo ($html ? '' : '').$hash.", size: ".$kSize."KB ($countFiles copies): ".($html ? '' : 0).$htmlEOL.PHP_EOL;
+ if ($html) {
+ echo "";
+ }
+ } else {
+ continue;
+ }
+ foreach ($files as $file) {
+ if ($file['link']) {
+ // This is a link. Discount from real files
+ // and do not count as potential space savings
+ $realFilesForThisHash--;
+ $totalLinks++;
+ } else {
+ if ($i != 0) {
+ // We don't count the first file as a duplicate
+ // nor as potential space savings
+ $totalDuplicateDocs++;
+ $totalDocsSize += $file['size'];
+ }
+ if ($html) {
+ echo "- ".$file['subpath']."(".$file['course'].")
".PHP_EOL;
+ } else {
+ echo $webCode.$file['course'].", as ".$file['path'].$htmlEOL.PHP_EOL;
+ }
+ $i++;
+ }
+ }
+ if ($html) {
+ echo "
";
+ }
+ if ($realFilesForThisHash > 0) {
+ // if at least one of those was really a file, count it as unique
+ if ($debug) {
+ echo "$hash (".$file['path'].") has $realFilesForThisHash duplicates".PHP_EOL;
+ }
+ $uniqueDocs++;
+ }
+}
+$duplicateDocsCount = $totalDocs - $uniqueDocs;
+
+$sizeInMB = floor((int) $totalDocsSize / (1024*1024));
+echo "[".time()."] Found $totalDocs docs in total (including links).".PHP_EOL;
+echo " Only $uniqueDocs were original files with duplicates.".PHP_EOL;
+echo " $totalDuplicateDocs files remain, as duplicates versions of some of those $uniqueDocs.".PHP_EOL;
+echo " Potential savings: ~$sizeInMB MB.".PHP_EOL;
+
+echo "";
+
+/**
+ * Scans the given directory and its subdirectories and returns a number of
+ * files found
+ * @param string $path
+ * @param array &$md5Hashes
+ * @param string $courseCode
+ * @param bool $ignoreTemplates
+ * @return int
+ */
+function _scanSubDirs(string $path, array &$md5Hashes, array &$md5Sizes, string $courseCode, bool $ignoreTemplates = false): int
+{
+ global $debug;
+ $count = 0;
+ if (!is_dir($path)) {
+ return 0;
+ }
+ if (substr(basename($path), 0, 1) === '.') {
+ // If last path component starts with a '.', ignore
+ return 0;
+ }
+ if ($ignoreTemplates) {
+ if (preg_match('#/document/(audio|flash|images|video)#', $path)) {
+ if ($debug) {
+ echo $path." is part of the template, skipping".PHP_EOL;
+ }
+ return 0;
+ }
+ }
+ $list = scandir($path);
+ foreach ($list as $entry) {
+ if (substr($entry, 0, 1) === '.') {
+ // If the entry starts with a '.', ignore
+ continue;
+ }
+ $subPath = $path.'/'.$entry;
+ if ($ignoreTemplates && preg_match('#/document/index.html$#', $subPath)) {
+ continue;
+ }
+ if (is_dir($subPath)) {
+ $count += _scanSubDirs($subPath, $md5Hashes, $md5Sizes, $courseCode, $ignoreTemplates);
+ } else {
+ $fileMd5 = md5_file($subPath);
+ if ($fileMd5 === false) {
+ if ($debug) {
+ echo 'Skipping: There was an error calculating MD5 of '.$subPath.PHP_EOL;
+ }
+ continue;
+ }
+ $fileSize = filesize($subPath);
+ if ($fileSize > 0) {
+ if (!isset($md5Hashes[$fileMd5])) {
+ $md5Hashes[$fileMd5] = [];
+ }
+ $matches = [];
+ preg_match('#/document/(.*)#', $subPath, $matches);
+ $isLink = is_link($subPath);
+ $md5Hashes[$fileMd5][] = [
+ 'course' => $courseCode,
+ 'link' => $isLink,
+ 'path' => $subPath,
+ 'size' => $fileSize,
+ 'subpath' => $matches[1],
+ ];
+ $md5Sizes[$fileMd5] = $fileSize;
+ } else {
+ if ($debug) {
+ echo 'Skipping: Filesize 0 for '.$subPath.PHP_EOL;
+ }
+ continue;
+ }
+ $count++;
+ }
+ }
+
+ return $count;
+}