MDL-55957 workshop: Fix the embedded files serving

There was a bug with serving the files from the areas instructauthors,
instructreviewers and conclusion. These three areas should not use the
itemid in the plugininfo URLs. But they did use 0 as the itemid which
broke the file previews when browsing via server files repository.

The first part of the patch fixes all relevant calls to
file_rewrite_pluginfile_urls() so that null is now properly used instead
of zero.

The second part of the fix is that we no longer delete the first $args
element in the workshop_pluginfile() function - the itemid is not
supposed to appear there now.

The last part of the patch is that instead of repeating the same code
block copy&pasted for each file area in workshop_pluginfile(), we now
have a single block covering them all.

mod/workshop/assessment.php

@@ -265,7 +265,7 @@
 // for evaluating the assessment
 if (trim($workshop->instructreviewers)) {
     $instructions = file_rewrite_pluginfile_urls($workshop->instructreviewers, 'pluginfile.php', $PAGE->context->id,
-        'mod_workshop', 'instructreviewers', 0, workshop::instruction_editors_options($PAGE->context));
+        'mod_workshop', 'instructreviewers', null, workshop::instruction_editors_options($PAGE->context));
     print_collapsible_region_start('', 'workshop-viewlet-instructreviewers', get_string('instructreviewers', 'workshop'));
     echo $output->box(format_text($instructions, $workshop->instructreviewersformat, array('overflowdiv'=>true)), array('generalbox', 'instructions'));
     print_collapsible_region_end();

mod/workshop/exassessment.php

@@ -143,7 +143,7 @@
 // for evaluating the assessment
 if (trim($workshop->instructreviewers)) {
     $instructions = file_rewrite_pluginfile_urls($workshop->instructreviewers, 'pluginfile.php', $PAGE->context->id,
-        'mod_workshop', 'instructreviewers', 0, workshop::instruction_editors_options($PAGE->context));
+        'mod_workshop', 'instructreviewers', null, workshop::instruction_editors_options($PAGE->context));
     print_collapsible_region_start('', 'workshop-viewlet-instructreviewers', get_string('instructreviewers', 'workshop'));
     echo $output->box(format_text($instructions, $workshop->instructreviewersformat, array('overflowdiv'=>true)), array('generalbox', 'instructions'));
     print_collapsible_region_end();

mod/workshop/exsubmission.php

@@ -187,7 +187,7 @@
 // while reading the submitted answer
 if (trim($workshop->instructauthors)) {
     $instructions = file_rewrite_pluginfile_urls($workshop->instructauthors, 'pluginfile.php', $PAGE->context->id,
-        'mod_workshop', 'instructauthors', 0, workshop::instruction_editors_options($PAGE->context));
+        'mod_workshop', 'instructauthors', null, workshop::instruction_editors_options($PAGE->context));
     print_collapsible_region_start('', 'workshop-viewlet-instructauthors', get_string('instructauthors', 'workshop'));
     echo $output->box(format_text($instructions, $workshop->instructauthorsformat, array('overflowdiv'=>true)), array('generalbox', 'instructions'));
     print_collapsible_region_end();

mod/workshop/lib.php

@@ -1302,43 +1302,15 @@ function workshop_pluginfile($course, $cm, $context, $filearea, array $args, $fo
 
     require_login($course, true, $cm);
 
-    if ($filearea === 'instructauthors') {
-        array_shift($args); // itemid is ignored here
+    if ($filearea === 'instructauthors' or $filearea === 'instructreviewers' or $filearea === 'conclusion') {
+        // The $args are supposed to contain just the path, not the item id.
         $relativepath = implode('/', $args);
         $fullpath = "/$context->id/mod_workshop/$filearea/0/$relativepath";
 
         $fs = get_file_storage();
         if (!$file = $fs->get_file_by_hash(sha1($fullpath)) or $file->is_directory()) {
             send_file_not_found();
         }
-
-        // finally send the file
-        send_stored_file($file, null, 0, $forcedownload, $options);
-
-    } else if ($filearea === 'instructreviewers') {
-        array_shift($args); // itemid is ignored here
-        $relativepath = implode('/', $args);
-        $fullpath = "/$context->id/mod_workshop/$filearea/0/$relativepath";
-
-        $fs = get_file_storage();
-        if (!$file = $fs->get_file_by_hash(sha1($fullpath)) or $file->is_directory()) {
-            send_file_not_found();
-        }
-
-        // finally send the file
-        send_stored_file($file, null, 0, $forcedownload, $options);
-
-    } else if ($filearea === 'conclusion') {
-        array_shift($args); // itemid is ignored here
-        $relativepath = implode('/', $args);
-        $fullpath = "/$context->id/mod_workshop/$filearea/0/$relativepath";
-
-        $fs = get_file_storage();
-        if (!$file = $fs->get_file_by_hash(sha1($fullpath)) or $file->is_directory()) {
-            send_file_not_found();
-        }
-
-        // finally send the file
         send_stored_file($file, null, 0, $forcedownload, $options);
 
     } else if ($filearea === 'submission_content' or $filearea === 'submission_attachment') {

mod/workshop/submission.php

@@ -296,7 +296,7 @@
 // while reading the submitted answer
 if (trim($workshop->instructauthors)) {
     $instructions = file_rewrite_pluginfile_urls($workshop->instructauthors, 'pluginfile.php', $PAGE->context->id,
-        'mod_workshop', 'instructauthors', 0, workshop::instruction_editors_options($PAGE->context));
+        'mod_workshop', 'instructauthors', null, workshop::instruction_editors_options($PAGE->context));
     print_collapsible_region_start('', 'workshop-viewlet-instructauthors', get_string('instructauthors', 'workshop'));
     echo $output->box(format_text($instructions, $workshop->instructauthorsformat, array('overflowdiv'=>true)), array('generalbox', 'instructions'));
     print_collapsible_region_end();

mod/workshop/view.php

@@ -148,7 +148,7 @@
 case workshop::PHASE_SUBMISSION:
     if (trim($workshop->instructauthors)) {
         $instructions = file_rewrite_pluginfile_urls($workshop->instructauthors, 'pluginfile.php', $PAGE->context->id,
-            'mod_workshop', 'instructauthors', 0, workshop::instruction_editors_options($PAGE->context));
+            'mod_workshop', 'instructauthors', null, workshop::instruction_editors_options($PAGE->context));
         print_collapsible_region_start('', 'workshop-viewlet-instructauthors', get_string('instructauthors', 'workshop'));
         echo $output->box(format_text($instructions, $workshop->instructauthorsformat, array('overflowdiv'=>true)), array('generalbox', 'instructions'));
         print_collapsible_region_end();
@@ -333,7 +333,7 @@
     }
     if (trim($workshop->instructreviewers)) {
         $instructions = file_rewrite_pluginfile_urls($workshop->instructreviewers, 'pluginfile.php', $PAGE->context->id,
-            'mod_workshop', 'instructreviewers', 0, workshop::instruction_editors_options($PAGE->context));
+            'mod_workshop', 'instructreviewers', null, workshop::instruction_editors_options($PAGE->context));
         print_collapsible_region_start('', 'workshop-viewlet-instructreviewers', get_string('instructreviewers', 'workshop'));
         echo $output->box(format_text($instructions, $workshop->instructreviewersformat, array('overflowdiv'=>true)), array('generalbox', 'instructions'));
         print_collapsible_region_end();
@@ -554,7 +554,7 @@
 case workshop::PHASE_CLOSED:
     if (trim($workshop->conclusion)) {
         $conclusion = file_rewrite_pluginfile_urls($workshop->conclusion, 'pluginfile.php', $workshop->context->id,
-            'mod_workshop', 'conclusion', 0, workshop::instruction_editors_options($workshop->context));
+            'mod_workshop', 'conclusion', null, workshop::instruction_editors_options($workshop->context));
         print_collapsible_region_start('', 'workshop-viewlet-conclusion', get_string('conclusion', 'workshop'));
         echo $output->box(format_text($conclusion, $workshop->conclusionformat, array('overflowdiv'=>true)), array('generalbox', 'conclusion'));
         print_collapsible_region_end();