When downloading events from the Events page. If the download file was deleted after downloading, we make the download link for the file inactive

[IgorA100]

In continuation: #4488

[IgorA100]

Please verify.

[Copilot]

Pull request overview

This PR extends the Events-page export/download workflow (from #4488) by polling the server for whether generated temporary download files still exist, and visually disabling download links in the modal once the files have been deleted.

Changes:

• Exposes DIR_EXPORTS_DOWNLOAD to the browser and uses it client-side to build file paths for polling.
• Adds client-side polling in export.js to periodically check file existence and mark download links as disabled.
• Adds a new AJAX action (file_existence_check) to return file_exists() results, plus CSS styling for disabled download links.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 6 comments.

File	Description
web/skins/classic/js/skin.js.php	Exposes DIR_EXPORTS_DOWNLOAD as a JS constant (server filesystem path).
web/skins/classic/js/export.js	Adds polling + UI disabling logic for download links after file deletion.
web/skins/classic/css/base/views/events.css	Styles disabled download links in the download modal.
web/ajax/event.php	Adds file_existence_check AJAX endpoint to check file presence.

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[IgorA100]

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[Copilot]

Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated 5 comments.

[IgorA100]

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[Copilot]

Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

[IgorA100]

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[Copilot]

Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated no new comments.

Comments suppressed due to low confidence (2)

web/skins/classic/js/export.js:46

• fileName is inserted using $j(nodeCopy).html(...), which treats it as HTML. Since the filename can include monitor names/user-controlled characters, this can introduce an XSS vector in the download modal. Use .text(...) (or build DOM nodes) and insert the <br> as a separate element instead of concatenating HTML.

          nodeCopy = downloadLink.cloneNode(true);
          nodeCopy.id = 'downloadLink'+i;
          downloadLink.parentNode.insertBefore(nodeCopy, downloadLink.nextSibling);
          $j(nodeCopy).html('<br>' + (i+1) + '. Download ' + '"' + fileName + '"');
          $j(nodeCopy).attr("href", thisUrl + file);

web/skins/classic/js/export.js:147

• fileExistencePollingInterval is only cleared when a new exportResponse() arrives. If the user clicks "Generate Download" again while the previous polling is still active (e.g., while the new export request is running), the old interval can keep polling and disabling links based on stale filenames. Clear the existing interval at the start of exportEvent() to stop stale polling immediately.

function exportEvent() {
  $j('#exportProgress').html('<span class="spinner-grow" role="status" aria-hidden="true"></span>Exporting...');
  $j('#exportProgress').removeClass( 'text-success text-danger text-warning' );
  $j('#exportProgress').addClass( 'text-warning invisible' );
  $j('#downloadLink').html( '' );

[IgorA100]

If the user clicks "Generate Download" again while the previous polling is still active

This PR doesn't fix the algorithm.
The next PR will implement replay protection.

[IgorA100]

Ready for verification.