PDF images don't convert in GitHub Actions

[rowanc1]

Need to investigate further on this one!

[jan-david-fischbach]

👍

[jan-david-fischbach]

For reference, this is the error I get:

2023-07-31T13:42:43.9808172Z Could not convert from PDF to PNG: _build/site/public/width_sweep-8bca976875a10bf293f360c1ef6fe9c8.pdf - Error: Command failed: convert -density 600 -colorspace RGB _build/site/public/width_sweep-8bca976875a10bf293f360c1ef6fe9c8.pdf _build/site/public/width_sweep-8bca976875a10bf293f360c1ef6fe9c8.png
2023-07-31T13:42:43.9809205Z convert-im6.q16: attempt to perform an operation not allowed by the security policy `PDF' @ error/constitute.c/IsCoderAuthorized/421.

[jan-david-fischbach]

@rowanc1 Seems to be an issue with imagemagick being very cautious with pdf conversion due to a ghostscript vulnerability: https://stackoverflow.com/questions/52998331/imagemagick-security-policy-pdf-blocking-conversion

[jan-david-fischbach]

- run: sudo apt-get update
- run: sudo apt-get -y install ghostscript
- run: sudo sed -i '/domain="coder" rights="none"/d' /etc/ImageMagick-6/policy.xml

This circumvents the bug. We should probably also make sure to install Ghostscript ≥9.24 to avoid the vulnerability

[rowanc1]

Love this, thank you! I think that if we start to make our own action #453, then we could start to incorporate these there for everyone. Right now the myst init --gh-pages puts you off on your own to add these (which can be good, but doesn't allow centralized updates!). There is an action we could start to copy here:
https://github.com/curvenote/action-myst-publish

Ideally a myst build github action that is configurable with PDF etc. (download latex, install packages, don't do it if you don't need to) would be super helpful, and be part of the pages deployment action as well.