EventStream Connection Error when trying to export

[pjohanneson]

Description

Can't export to PDF -- I get EventStream Connection Error when attempting to export a book.

Expected behaviour

I want to be able to export my book to PDF. Other exports are successful.

Actual behaviour

When attempting to export to PDF, I get the error message EventStream Connection Error.

Steps to reproduce the problem

• Installed pressbooks-mPDF.
• Followed the installation instructions here.
• Ensured that the server ID www-data could write to the directories:
  • wp-content/plugins/pressbooks-mpdf/symbionts/mpdf/ttfontdata
  • wp-content/plugins/pressbooks-mpdf/symbionts/mpdf/tmp
  • wp-content/plugins/pressbooks-mpdf/symbionts/mpdf/graph_cache
• Installed or updated the PHP libraries gd, mbstring, bcmath, and xml.
• Restarted Apache.
• Went to [server]/[site]/wp-admin/options.php?page=pb_export and attempted to export to PDF (mPDF).

System Information

• mPDF for Pressbooks: 3.2.4
• Pressbooks: 5.7.0
• WordPress: 5.1.1

[bdolor]

@pjohanneson I suspect the error is being thrown here: https://github.com/pressbooks/pressbooks/blob/c28981f5cf6c35e7fb8b90dda88e633d1efff423/assets/src/scripts/export.js#L80

I've tried recreating this locally but cannot. Export functionality works as expected.

BTW I will be releasing a patch version of mPDF shortly, but I'm not sure it will address the issue you're experiencing.

Has mPDF worked for you before or is this a new install?

[pjohanneson]

This is a new install of mPDF, though I've had PressBooks installed for a while. I may spin up a VM and see if I can make the error happen again.

[bdolor]

If it's a content related problem and your book is openly licensed/shareable you could point to it and we could troubleshoot from there.

[pjohanneson]

Fixed. I was using a Github-sourced version of the plugin, and I hadn't run composer install, so I was missing dependencies. Mea culpa.